Some Frequently Asked Questions about Solar Eclipses
If you want specific details and maps, see our pages for each of these eclipses:
20 April 2023 22 July 2028 25 November 2030 13 July 2037 26 December 2038
the other 21st century Australian solar eclipses
20 April 2023 22 July 2028 25 November 2030 13 July 2037 26 December 2038
the other 21st century Australian solar eclipses
In astronomy an eclipse is simply Something moving in front of Something Else, and blocking the view of the Something Else.
During a solar eclipse the Moon moves in front of the Sun, as seen from Earth. During a lunar eclipse the Earth moves in front of the Sun, as seen from the Moon.
If the Something looks much smaller than the Something Else, then astronomers describe the event as a transit of the Something across the Something Else. For example the planets Mercury and Venus occasionally transit the Sun, as seen from Earth.
During a solar eclipse the Moon moves in front of the Sun, as seen from Earth. During a lunar eclipse the Earth moves in front of the Sun, as seen from the Moon.
If the Something looks much smaller than the Something Else, then astronomers describe the event as a transit of the Something across the Something Else. For example the planets Mercury and Venus occasionally transit the Sun, as seen from Earth.
It all depend on where the Moon's shadow is, in relation to where you are on Earth.
Total and annular eclipses are preceded and followed by 50 to 90 minutes of partial eclipse; unless they're happening near local sunrise or sunset. An early morning event may begin with a partial eclipse underway at sunrise. Similarly a late afternoon event may end with a partial eclipse still happening at sunset -- which will be the case for all of Queensland during the 25 Nov 2030 eclipse.
- During a total eclipse the Moon's shadow is on the Earth's surface, and you're inside the shadow. The bright Sun is completely hidden from view by the Moon for a short time.
- During an annular eclipse the Moon is too far away for its shadow to reach the Earth's surface. Most but not all of the Sun's disc is hidden by the Moon, leaving a bright ring of sunlight still visible around the Moon.
- During a partial eclipse the Sun's disc is only partly hidden by the Moon. The Moon's shadow (and any total / annular eclipse) is far away from wherever you are...and might not even be anywhere on the Earth's surface at that moment. If less than 3/4 of the Sun is covered you may not even notice a partial eclipse is happening.
- You get a beaded eclipse if you're less than two kilometres outside the path of a total solar eclipse. During this not-quite-total eclipse there will always be bright bits of the Sun continuously visible around the Moon's black disc; due to sunlight shining through low terrain on the Moon's edge. The effect is often compared to an arc or partial ring of sparkling beads -- hence the name -- and it lasts for several seconds. Yes these beads look amazing but unfortunately they're also bright enough to blot out most of the other visual phenomena unique to total eclipses.
Total and annular eclipses are preceded and followed by 50 to 90 minutes of partial eclipse; unless they're happening near local sunrise or sunset. An early morning event may begin with a partial eclipse underway at sunrise. Similarly a late afternoon event may end with a partial eclipse still happening at sunset -- which will be the case for all of Queensland during the 25 Nov 2030 eclipse.
For the entire Earth during the 21st century there will be 224 solar eclipses: 77 partial, 72 annular, 68 total, and 7 which are combined annular+total (such as 20 April 2023). That's 75 total eclipses somewhere on Earth in 100 years, or an average of 3 total eclipses per 4 years. But many of those eclipses will only be visible from hard-to-reach places like the middle of an ocean.
Total solar eclipses aren't evenly spaced in time either. For example there's only 176 days between the eclipses on 6 December 2067 and 31 May 2068, but there's 856 days between the total eclipses on 22 July 2028 and 25 November 2030.
At any specific point you might be waiting for a very long time between its total solar eclipses. For example the most recent and the next Total Solar Eclipses in Australian capital city centres are:
All of these cities already extend tens of km from their centres, so any eclipse that's 98+ percent at the city centre is likely to be a total eclipse for some outer suburbs.
Lunar eclipses are much more frequent for any specific point. For example during the 21st century Adelaide city will witness 46 total lunar eclipses plus another 30 partial lunar eclipses.
Total solar eclipses aren't evenly spaced in time either. For example there's only 176 days between the eclipses on 6 December 2067 and 31 May 2068, but there's 856 days between the total eclipses on 22 July 2028 and 25 November 2030.
At any specific point you might be waiting for a very long time between its total solar eclipses. For example the most recent and the next Total Solar Eclipses in Australian capital city centres are:
- Adelaide: 4 March 1802 --- 8 January 4039 (yes, over 2200 years!).
(but Adelaide does see the 6 February 2418 annular eclipse, and its northernmost suburbs today should be just inside the 11 May 2795 total solar eclipse) - Brisbane: 8 August 1831 --- 13 July 2037 (206 years).
(Brisbane also sees the 27 January 2093 total solar eclipse, making it the first Australian state/territory capital city centre to see three total solar eclipses) - Canberra: 4 July 1247 --- 31 May 2337 (1090 years)
(but Canberra does see the 14 October 2042 annular solar eclipse) - Darwin: 24 June 1256 --- 13 October 2349 (1093 years)
(but the 14 November 2012 total solar eclipse began near Darwin) - Hobart: 9 May 1910 --- 29 November 2551 (641 years)
- Melbourne: 23 October 1976 --- 4 April 2220 (244 years)
- Perth: 27 July 1310 --- 16 October 2851 (1541 years)
(Perth city centre is less than two kilometres outside the northern limit of the 31 May 2068 total solar eclipse; so technically some of suburban Perth sees this eclipse) - Sydney: 26 March 1857 --- 22 July 2028 (171 years)
(Sydney is the first Australian state/territory capital city centre to see two total solar eclipses. It also sees the 11 April 2089 annular solar eclipse, and its southernmost suburbs today will also see the 14 October 2042 annular solar eclipse)
All of these cities already extend tens of km from their centres, so any eclipse that's 98+ percent at the city centre is likely to be a total eclipse for some outer suburbs.
Lunar eclipses are much more frequent for any specific point. For example during the 21st century Adelaide city will witness 46 total lunar eclipses plus another 30 partial lunar eclipses.
For solar eclipses:
If you're unaware that a solar eclipse is predicted for your location, then you probably won't notice anything unusual until the Obscuration exceeds about 0.75 (75%) and the Sun has shrunk down to a fat crescent.
For lunar eclipses, the magnitude is the fraction or percentage of the Moon's diameter that is covered by the Earth's shadow. A lunar eclipse magnitude can be much larger than 1 because the Earth's shadow (at lunar distance) is much larger than the Moon.
- Magnitude = the fraction (0.0 to 1.0) of the Sun's diameter that is covered by the Moon. For a total solar eclipse, the Magnitude is slightly greater than 1.
- Obscuration = the fraction of the Sun's disc area that is covered by the Moon.
If you're unaware that a solar eclipse is predicted for your location, then you probably won't notice anything unusual until the Obscuration exceeds about 0.75 (75%) and the Sun has shrunk down to a fat crescent.
For lunar eclipses, the magnitude is the fraction or percentage of the Moon's diameter that is covered by the Earth's shadow. A lunar eclipse magnitude can be much larger than 1 because the Earth's shadow (at lunar distance) is much larger than the Moon.
NO! And here's an analogy...
- A Total Solar Eclipse is like being in the best seats of the greatest concert or show you've ever been to.
- A beaded eclipse is like being in the outer seats of the concert, behind a large pillar, and wearing noise-cancelling headphones.
- A 99.9% partial eclipse is like standing in the car park outside of the concert. You might be able to hear some of the music, some of the time, but not very well. You may even get hints of the visual effects if it's an outdoor concert. But try telling your friend, who was actually in the best seats, about your Fabulous Concert Experience and they'll just laugh at you.
- A 99% partial eclipse is like being in the same suburb as the concert. You see a lot of extra traffic and visitors, and you get a definite impression that Something Is Happening Nearby -- but that's about it.
- A 90% partial eclipse is like being in the same major city as the concert. You may not even notice it unless you knew about it in advance.
A total eclipse is preceded (and followed) by 55-90 minutes of partial eclipse. So your first indication of the event is when a tiny "dent" appears on the edge of the Sun's disc.
That "dent" is the edge of the approaching Moon, and during the next 30-40 minutes that tiny dent becomes a big circular bite out of the Sun's disc.
Yet the landscape around you seems as bright as ever because the decrease in sunlight, so far, is no different to the Sun going behind a small cloud. And your eyes have had plenty of time to adapt to the reduction in sunlight.
If you didn't know there was a solar eclipse today you may not even notice anything unusual. But if you look at the shadows cast by foliage, you notice all of the usual round sun-dapples have become crescents. Natural pinhole projections...and those crescents are slowly shrinking.
About 10 minutes before total eclipse, you suddenly notice the sunlight doesn't feel warm anymore. And the air is getting colder. The sky is developing a curious twilight-blue colour. Shadows are looking peculiar, as though they're being cast by continuous lightning or an Arc Welder. You look through your eclipse filter at the Sun, which is now a brilliant but rapidly shrinking crescent.
And then you look at the western sky, shortly before total eclipse, and you see a vast and silent Darkness has appeared there. And then you realise it's rushing towards you, flooding the landscape and any clouds beneath it. The landscape around you is rapidly falling into the darkness of deep twilight. Colours are reducing to shades of grey. Birds and other wildlife are behaving as though it's a sunset. The Sun has shrunk to an ever-thinning crescent, which breaks into an arc of brilliant pinpoints on one side of an increasingly obvious black disc outlined by a glowing rim. And as the final pinpoint of sunlight vanishes, you see it...
You are in the Shadow Of The Moon. The Sun you knew has transformed into a black disc surrounded by a soft white halo. This halo -- the Sun's corona -- is about as bright as full moonlight next to the black disc, fading into the background sky away from the disc. At the very edge of the black disc, you might see tiny red glows within the corona. These red glows are solar prominences, ever-changing and never repeating clouds of hot gases poised above the Sun's edge. As your eyes adapt to the deep twilight darkness, you see the corona is textured with delicate lines and rays and streamers, sculpted by the complex and restless magnetic fields above the Sun. You imagine tangled hair, tentacles, spines, flames reaching outwards into the sky. No single-exposure photo, no video, has ever shown it like this.
You tear your gaze away from the Thing that has replaced the Sun. The sky is twilight, not the black of deep night, but you can see some of the brighter stars and planets. The vast Darkness overhead is surrounded by sunset sky colours on every horizon. You hear other people shouting, cheering, screaming with excitement. Or struck utterly silent in reverent awe.
You think briefly, and with pity, about the guy who said he was going to stay home and watch a 99% eclipse. He's not seeing the Thing, its vast Darkness, the un-earthly sky, the ecstatic witnesses...but YOU are.
And then you notice the western horizon's sunset seems to be rising and getting brighter. So you return your gaze to the Thing. You sense that the black disc has moved across the corona since the beginning of total eclipse. The normal daytime sky is about to return. It begins with a searingly-bright pinpoint of sunlight on the edge of the black disc, quickly joined by other pinpoints that merge into a dazzling curved line of sunlight. The corona vanishes; blotted from view by the returning sunlight and your sudden loss of night vision. If you want to keep watching you'll need your eclipse filter again.
A crescent Sun returns, but now it's facing the other way, and during the next 10 to 15 minutes the warmth of the sunlight and the normal colours and shadows of the landscape return. It's still another hour or so before the Moon moves completely off the Sun, but already it looks like a normal day again. Except for the excited witnesses, and the question uppermost in all of their minds:
About 10 minutes before total eclipse, you suddenly notice the sunlight doesn't feel warm anymore. And the air is getting colder. The sky is developing a curious twilight-blue colour. Shadows are looking peculiar, as though they're being cast by continuous lightning or an Arc Welder. You look through your eclipse filter at the Sun, which is now a brilliant but rapidly shrinking crescent.
And then you look at the western sky, shortly before total eclipse, and you see a vast and silent Darkness has appeared there. And then you realise it's rushing towards you, flooding the landscape and any clouds beneath it. The landscape around you is rapidly falling into the darkness of deep twilight. Colours are reducing to shades of grey. Birds and other wildlife are behaving as though it's a sunset. The Sun has shrunk to an ever-thinning crescent, which breaks into an arc of brilliant pinpoints on one side of an increasingly obvious black disc outlined by a glowing rim. And as the final pinpoint of sunlight vanishes, you see it...
Total. Solar. Eclipse.
You are in the Shadow Of The Moon. The Sun you knew has transformed into a black disc surrounded by a soft white halo. This halo -- the Sun's corona -- is about as bright as full moonlight next to the black disc, fading into the background sky away from the disc. At the very edge of the black disc, you might see tiny red glows within the corona. These red glows are solar prominences, ever-changing and never repeating clouds of hot gases poised above the Sun's edge. As your eyes adapt to the deep twilight darkness, you see the corona is textured with delicate lines and rays and streamers, sculpted by the complex and restless magnetic fields above the Sun. You imagine tangled hair, tentacles, spines, flames reaching outwards into the sky. No single-exposure photo, no video, has ever shown it like this.
You tear your gaze away from the Thing that has replaced the Sun. The sky is twilight, not the black of deep night, but you can see some of the brighter stars and planets. The vast Darkness overhead is surrounded by sunset sky colours on every horizon. You hear other people shouting, cheering, screaming with excitement. Or struck utterly silent in reverent awe.
You think briefly, and with pity, about the guy who said he was going to stay home and watch a 99% eclipse. He's not seeing the Thing, its vast Darkness, the un-earthly sky, the ecstatic witnesses...but YOU are.
And then you notice the western horizon's sunset seems to be rising and getting brighter. So you return your gaze to the Thing. You sense that the black disc has moved across the corona since the beginning of total eclipse. The normal daytime sky is about to return. It begins with a searingly-bright pinpoint of sunlight on the edge of the black disc, quickly joined by other pinpoints that merge into a dazzling curved line of sunlight. The corona vanishes; blotted from view by the returning sunlight and your sudden loss of night vision. If you want to keep watching you'll need your eclipse filter again.
A crescent Sun returns, but now it's facing the other way, and during the next 10 to 15 minutes the warmth of the sunlight and the normal colours and shadows of the landscape return. It's still another hour or so before the Moon moves completely off the Sun, but already it looks like a normal day again. Except for the excited witnesses, and the question uppermost in all of their minds:
WHEN AND WHERE CAN I SEE MY NEXT TOTAL SOLAR ECLIPSE?
This is an overlooked aspect of eclipse safety, so we've included a lot of more specific comments on each of the eclipse pages for
2023, 2028, 2030, 2037 and 2038. Some general comments follow.
Most of Australia is sparsely populated and has long driving distances between towns and the various state/territory capitals. Which is why Australia has a well-developed domestic airline and air charter industry, as well as several international airlines offering direct flights into various Australian cities.
Nearly all of Australia's highways outside of the major cities provide only a single traffic lane in each direction, and there are many long intervals where there are no safe (or legal) overtaking opportunities if you're behind a slower vehicle. This issue is (slowly) being fixed with the construction of overtaking lanes along major roads.
If it's a warm day then heat mirages on the road can make it impossible to estimate the distance or speed of any oncoming traffic. And if you're travelling on an unsealed road then your safest option is Never Overtake, because you can't see past their dust cloud unless they are travelling very slowly.
Heavy vehicles are maximum speed limited to 100 kilometres per hour by their engine power controls. But they may be going slower if they're carrying dangerous or oversize freight, on a bad road surface, a winding road, or driving uphill. They could also be going faster than 100 if they're travelling downhill, because gravity provides the acceleration that their engine won't.
If you're not an experienced traveller then we highly recommend watching Visit Corner Country's excellent series of videos about driving safely in the Australian Outback.
If you intend to drive many hundreds of kilometres to an eclipse then don't do it all on eclipse day. Traffic on eclipse day will be intense, all of it will be travelling at the speed of the slowest vehicle, there will be queues for fuel and recharging, and there will be some breakdowns or accidents causing more delays. Also for similar reasons don't plan on driving many hundreds of kilometres immediately after the eclipse. Plan on staying in (or near) the total eclipse path for a few days instead, before and after the eclipse. Catch up with friends out there, compare and share your experiences, and check out some non-eclipse things to do nearby. Make the eclipse an important, but not the exclusive, reason for your visit.
If you're hoping to see the eclipse from a roadside in the middle of nowhere:
Most of Australia is sparsely populated and has long driving distances between towns and the various state/territory capitals. Which is why Australia has a well-developed domestic airline and air charter industry, as well as several international airlines offering direct flights into various Australian cities.
Nearly all of Australia's highways outside of the major cities provide only a single traffic lane in each direction, and there are many long intervals where there are no safe (or legal) overtaking opportunities if you're behind a slower vehicle. This issue is (slowly) being fixed with the construction of overtaking lanes along major roads.
If it's a warm day then heat mirages on the road can make it impossible to estimate the distance or speed of any oncoming traffic. And if you're travelling on an unsealed road then your safest option is Never Overtake, because you can't see past their dust cloud unless they are travelling very slowly.
Heavy vehicles are maximum speed limited to 100 kilometres per hour by their engine power controls. But they may be going slower if they're carrying dangerous or oversize freight, on a bad road surface, a winding road, or driving uphill. They could also be going faster than 100 if they're travelling downhill, because gravity provides the acceleration that their engine won't.
If you're not an experienced traveller then we highly recommend watching Visit Corner Country's excellent series of videos about driving safely in the Australian Outback.
If you intend to drive many hundreds of kilometres to an eclipse then don't do it all on eclipse day. Traffic on eclipse day will be intense, all of it will be travelling at the speed of the slowest vehicle, there will be queues for fuel and recharging, and there will be some breakdowns or accidents causing more delays. Also for similar reasons don't plan on driving many hundreds of kilometres immediately after the eclipse. Plan on staying in (or near) the total eclipse path for a few days instead, before and after the eclipse. Catch up with friends out there, compare and share your experiences, and check out some non-eclipse things to do nearby. Make the eclipse an important, but not the exclusive, reason for your visit.
If you're hoping to see the eclipse from a roadside in the middle of nowhere:
- Check your car before you leave home (or leave the car rental place). Is there any maintenance due? Is the spare wheel aboard, and correctly inflated? Does your car even have a spare wheel -- many newer cars don't! Do you have the other tools (and knowledge) to change a flat tyre on your car? Don't rely on Roadside Assist getting to you quickly...or at all.
Do all your car's lights and turn indicators work? If you're carrying things on a roof rack or in a trailer or in a ute tray, are they securely tied down?
- If you're towing a caravan or trailer; also check its lights, turn indicators, brakes, tyres, spare wheel(s) and wheel bearings before you leave home.
- Do you know how far apart your car's refuelling or recharging stops will be? Where and what do you plan to eat? Where are you staying, and do you need to pre-book this accommodation?
- Check the latest weather and road conditions reports; especially if you plan to be driving on unsealed rural or Outback roads. You do not want to be the idiot who gets trapped in the middle of nowhere for days, because you drove out there just before the predicted flooding began. Nor do you want to be paying the large fines for driving on a road that's officially Closed due to earlier floods or flood damage.
Click here for an example of a road conditions report, showing all of the unsealed roads in the Gawler Ranges in SA as passable to four wheel drive only. - Find somewhere to park where you won't obstruct passing traffic. Regular traffic in the rural and Outback parts of Australia includes lots of double semi-trailers, plus triple and quadruple road trains. These heavy vehicles weigh much more than your car (or motorhome), they need a lot of stopping distance, and they need a lot of turning room to change direction.
Some roadside parking areas are specifically for heavy vehicles to use for their mandatory rest breaks, and they must not be used by cars / caravans / motorhomes unless it's an emergency. - Did you bring a chair or a picnic blanket to sit on, while you wait for the eclipse? Did you also bring water? Snacks? Other drinks? Sunscreen and a hat, or something to provide shade?
- Do you need any essential medications out there with you? Do they need to be kept cold?
- If you're camping out there, did you check and pack all of your camping equipment? And food? And water?
- What are you using for a toilet? Leaving used toilet paper and excreta on the landscape is disgusting and unhygienic -- use a shovel and bury it out of sight! Better still, bring a self-contained chemical toilet, or a "thunder bucket". And dispose the contents into an RV Dump Point or into your toilet at home.
Urinating behind a bush in the middle of nowhere is rarely a problem. Most Australian soils are severely deficient in nitrogen so you'll be doing the bush a favour. - Do you have a first aid kit? And someone who knows first aid?
- Mobile phone coverage is limited or non-existent in many parts of Australia. Consider travelling in a group of vehicles, or bring a satellite phone, or a satellite distress beacon (PLB / EPIRB). At the very least let someone else know of your travel plans and when you expect to return -- so they can raise the alarm if you're "missing".
- If you get bogged or have a mechanical breakdown in a remote region then STAY WITH YOUR VEHICLE until help arrives. And try to stay out of the sun if it's a hot day. A car is much easier for rescuers to find, and many people stranded in rural and Outback Australia have died of thirst while attempting to walk for help.
a.k.a. "I don't want to burn my eyeballs...."
Looking directly at a TOTAL solar eclipse requires no eye protection at all and is quite safe. The Sun's light is being totally blocked by a ball of rock about the same size as Australia -- but only for the duration of the total eclipse. At all other times when you look directly at the Sun, you will need to protect your eyes with a solar filter product (a.k.a. eclipse glasses / eclipse shades / eclipse viewers / eclipse filters). We discuss these products below. And whenever you're looking directly at a partial solar eclipse or an annular solar eclipse (or a beaded eclipse), your eyes will need to be protected at all times.There are other ways to safely view the Sun if it's not totally eclipsed. For example:
- The classic Pinhole Projection method. All you need is a piece of cardboard (or thick paper) with a small hole in it, plus a white or light-coloured surface to project the Sun's image onto. This may be another piece of card. The hole should be 3 to 5 millimetres in diameter, without ragged edges. Download our instructions for a pinhole projector. Try making the hole with various size nails or hole punches. Try making holes in various patterns for artistic effects. But don't look directly at the Sun through the holes.
You may have items at home that include suitable holes. For example graters, colanders, sieves, loosely-woven straw hats or straw matting.
The foliage of many Australian native trees and shrubs provides a multitude of natural "pinholes" and Sun images within their shadows. During partial eclipses these images will appear as crescents.
(above) A pinhole projection of an un-eclipsed Sun, using scrap cardboard and a garage door.
(below) The 20 April 2023 solar eclipse, viewed safely with a $2 strainer spoon.
- Projection from a monocular, a binocular or a very small telescope. This will produce a larger and brighter image than Pinhole Projection and is good for safely showing a partial eclipse to groups. Visibility of the image will be improved if it's in a shadow (see our photos below).
But:
- Never leave this equipment unattended.
- Never let anyone look through the monocular / binocular / telescope at any time.
- Ensure that all lenses, mirrors, eyepieces (and their mountings) contain no plastic parts at all. Unfortunately a lot of the cheaper telescopes and binoculars do use plastic parts; and intense, concentrated sunlight will melt or burn them. Metal parts can get hot enough to cause burns. Glass in eyepieces may crack from the thermal stress. Which is why we don't use expensive eyepieces for this job...and we would never use a larger telescope.
(above) Safely observing the 20 April 2023 eclipse aboard Pacific Explorer anchored near Exmouth. The tripod is supporting a camera fitted with a removable solar filter film, plus half of an old 8x40 binocular projecting the Sun's image onto a tilted plywood sheet placed on the ship's deck. Another plywood sheet fitted around the (mon)ocular produces a shadow.
(below) A closeup of the nearly eclipsed Sun's projected image from the (mon)ocular, plus another view of the straining spoon image. Plus an accidental pinhole projection from an old nail hole in the plywood. Also note the abnormal edges on shadows at this time.
- A specialised solar telescope. Designed specifically to look at the Sun but useless for looking at anything else. And not cheap either. But the views through them are fascinating.
Of course watching a lunar eclipse requires no eye protection at all.
These are all products specifically designed to let you look safely at the Sun:
Before each use, check that your product has no scratches / abrasions / pinholes or other damage, and that it hasn't separated from its frame or mounting.
Use a bright light, not the Sun, for this safety check.
Total solar eclipses nowadays attract huge audiences, especially if they happen to pass over large cities such as Sydney or Brisbane. Or if they occur soon after a huge audience has seen another total eclipse recently. And everyone will want a solar filter to use on eclipse day. And many of the first-time eclipse watchers won’t think of getting a filter until a week or so beforehand, believing solar filter products are as readily available as beer or bread. Which is when they discover most of the reputable sources have already sold out and won't have new stocks available until after eclipse day.
Which then leads to:
The best way to avoid scalpers and counterfeiters is DO NOT BUY YOUR SOLAR FILTER PRODUCTS from online marketplaces like Amazon or Ebay or Facebook Marketplace or Gumtree or Temu. Also don't buy from whatever pops up #1 in a web search for these products. Why not? Because the scalpers and counterfeiters infest these marketplaces during the weeks before every solar eclipse.
Some Australian retailers of various safe solar filter products include (in alphabetical order):
Some manufacturers of ISO 12312-2 compliant solar filter product(s) include (in alphabetical order):
Large orders directly from the manufacturers can be customised with your own design or logo, and the per-item cost is considerably lower. We discovered that smaller orders directly from some international suppliers to our Australian rural address defaulted to eye-wateringly high shipping costs. It's well worth asking them directly if they can send your order as an ordinary international parcel that's delivered to you by Australia Post. We found it reduced the shipping costs to us to about 1/10 of the default price, and we still got the parcels in a couple of weeks.
The American Astronomical Society also maintains a huge list of reputable manufacturers and retailers.
Notes on specific products / suppliers:
The two simple rules to remember about positioning your safe solar filter product:
Filters that are stored inside a sealed container or envelope will last for many years in cool, dry conditions. Before using an old solar filter again, check that it has no scratches, abrasions, pinholes or other damage, and that it hasn't separated from its frame or mounting. Use a bright light, not the Sun, for this safety check (see the photos above). If in doubt, discard it and replace with a new filter.
Filters WILL be damaged by sand / coins / keys / zippers / mobile phones / other random items in pockets or handbags. They're also damaged by moisture and Lens Cleaning products.
And finally, here's a list of some so-called "sun filters" that are UNSAFE !
The damage to your eyesight from unsafe viewing of the Sun is painless, because your eyeball contains no pain nerves. But the damage is PERMANENT and IRREVERSIBLE.
- Eclipse glasses a.k.a. eclipse shades -- Intended to be worn like regular sunglasses. The frame is made from a double layer of heavy paper or light cardboard, with the special polymer solar filter material sandwiched between the layers where the lenses would be on regular sunglasses. Most are intended for adults, but kid-sized versions are available from some manufacturers. Generally not convenient if you need to wear prescription glasses, because you will have to hold the the eclipse glasses in place over your usual glasses.
- Eclipse viewers -- Similar construction to the eclipse glasses, but in the form of a small postcard with a window of solar filter material in it. Intended to be held in front of your eyes and suitable for most ages. And they can be attached to a neck lanyard. This is the better option if you already wear prescription glasses. The card can also be combined with a cut-out paper plate or cardboard box to make a little kid's "eclipse facemask".
- Eclipse / solar (filter) film -- Usually means the un-mounted polymer filter material, sold as a sheet or a roll. Intended for people who are making a custom filter to put on the front of their own telescopes / binoculars / cameras. Can also be used to make your own "eclipse facemask" or customised viewer.
- Solar filters -- Intended for installation on the front end of telescopes or cameras, and usually manufacturer-specific. May be made from specially coated optical glass instead of polymer filter material, supported in a metal ring or sleeve. Some manufacturers also sell sun-viewing-only versions of their telescopes or binoculars, with these solar filters permanently installed.
Before each use, check that your product has no scratches / abrasions / pinholes or other damage, and that it hasn't separated from its frame or mounting.
Use a bright light, not the Sun, for this safety check.
The current International Standard for all these solar filter products is ISO 12312-2 (2015),
which has been adopted in Australia -- unchanged -- as the Australian Standard AS ISO 12312.2 :2020.
Products that comply with ISO 12312-2 / AS ISO 12312.2 are safe for looking at the Sun, when used as directed.
And the Standards require the directions for safe use to be printed on the products (as shown above).
Use a bright light -- NOT the Sun -- to check your solar filter for any pinholes / scratches / cracks.
You should buy your solar filter products (glasses, viewers, etc) long before eclipse day.
which has been adopted in Australia -- unchanged -- as the Australian Standard AS ISO 12312.2 :2020.
Products that comply with ISO 12312-2 / AS ISO 12312.2 are safe for looking at the Sun, when used as directed.
And the Standards require the directions for safe use to be printed on the products (as shown above).
Use a bright light -- NOT the Sun -- to check your solar filter for any pinholes / scratches / cracks.
Total solar eclipses nowadays attract huge audiences, especially if they happen to pass over large cities such as Sydney or Brisbane. Or if they occur soon after a huge audience has seen another total eclipse recently. And everyone will want a solar filter to use on eclipse day. And many of the first-time eclipse watchers won’t think of getting a filter until a week or so beforehand, believing solar filter products are as readily available as beer or bread. Which is when they discover most of the reputable sources have already sold out and won't have new stocks available until after eclipse day.
Which then leads to:
- SCALPERS selling genuine solar filter products at highly inflated prices, and...
- COUNTERFEITERS promoting fake (and unsafe) "filters", made cheaply from things like builder's black plastic film or foil blankets, and sometimes sold at inflated prices too.
The counterfeiters often copy reputable manufacturers' logos and trademarks, claim approval from NASA or other space agencies, and frequently will include fake "certification" too.
The best way to avoid scalpers and counterfeiters is DO NOT BUY YOUR SOLAR FILTER PRODUCTS from online marketplaces like Amazon or Ebay or Facebook Marketplace or Gumtree or Temu. Also don't buy from whatever pops up #1 in a web search for these products. Why not? Because the scalpers and counterfeiters infest these marketplaces during the weeks before every solar eclipse.
Some Australian retailers of various safe solar filter products include (in alphabetical order):
- Astro Shop -- www.astroshop.com.au
- Binocular & Telescope Shop (Bintel) -- www.bintel.com.au
- Celestron Australia -- www.celestron.com.au
- Optics Central -- www.opticscentral.com.au
- Oz Scopes -- www.ozscopes.com.au
- Siderial Trading -- www.siderialtrading.com.au
- Sirius Optics -- www.sirius-optics.com.au
- Skywatcher Australia -- skywatcheraustralia.com.au
- Testar -- www.testar.com.au
- Also many other Australian retailers who sell solar filter product(s) from one of the manufacturers listed below.
Some manufacturers of ISO 12312-2 compliant solar filter product(s) include (in alphabetical order):
- American Paper Optics -- www.eclipseglasses.com
- American Paperwear --- ampaperwear.com
- APM Telescopes -- www.apm-telescopes.net/en/sonnenbeobachtung
- Baader Planetarium -- astrosolar.com/en
- Daystar Solar Filters -- shop.icstars.com
- Hangzhou Retsing -- www.retsing.com (wholesale quantities only)
- Lunt Solar -- luntsolarsystems.com
- Rainbow Symphony -- www.rainbowsymphonystore.com
- Thousand Oaks Optical -- thousandoaksoptical.com
Large orders directly from the manufacturers can be customised with your own design or logo, and the per-item cost is considerably lower. We discovered that smaller orders directly from some international suppliers to our Australian rural address defaulted to eye-wateringly high shipping costs. It's well worth asking them directly if they can send your order as an ordinary international parcel that's delivered to you by Australia Post. We found it reduced the shipping costs to us to about 1/10 of the default price, and we still got the parcels in a couple of weeks.
The American Astronomical Society also maintains a huge list of reputable manufacturers and retailers.
Notes on specific products / suppliers:
- Baader Planetarium's newer AstroSolar Gold Film and AstroSolar Silver Film are both fully compliant with ISO 12312.2. Their older product AstroSolar Safety Film complied with the older European Union safety standards but lets through slightly too much ultraviolet light to comply with the more stringent ISO 12312.2. So by itself it won't fully protect your eyeballs.
However the combination of AstroSolar Safety Film + a thin layer of glass (which blocks ultraviolet) is compliant with ISO 12312.2; so AstroSolar Safety Film is safe to use on a telescope / binocular / camera / mobile phone. It's also safe when used in front of your prescription glasses. - Celestron also sells sun-viewing-only versions of some of their telescopes and binoculars; with solar filters permanently installed.
- Daystar and Lunt Solar both also sell hydrogen-alpha Solar Telescopes; another safe (but expensive) way to view the Sun.
- Skywatcher also sells the Solarquest Heliofind mount; which uses a GPS-equipped sun sensor to automatically find and track the Sun. Use it with their Solar Telescope or yours. Or with cameras (you will also need a dove-tail adaptor bracket).
- Incidentally a Shade 12 or darker Arc Welding eyeshield also happens to comply with ISO 12312.2. Although many people will think the sun is still too bright through Shade 12 and would prefer the even darker Shade 13 or 14.
Don't use an auto-darkening electronic welder's helmet; most of them only go to Shade 11 at most, which isn't safe enough for directly viewing the sun.
The two simple rules to remember about positioning your safe solar filter product:
- THE SUN
--then--
YOUR SOLAR FILTER PRODUCT
--then--
your eyeballs / camera / binoculars / telescope / mobile phone. - THE FILTER MUST BE USED AT ALL TIMES WHEN LOOKING AT THE SUN , except during the brief moment of Total Solar Eclipse.
And if you're not expecting a total solar eclipse where you are, then don't stop using the filter at all. - And a third rule, if your kids are using a solar filter: SUPERVISE THEM....
Filters that are stored inside a sealed container or envelope will last for many years in cool, dry conditions. Before using an old solar filter again, check that it has no scratches, abrasions, pinholes or other damage, and that it hasn't separated from its frame or mounting. Use a bright light, not the Sun, for this safety check (see the photos above). If in doubt, discard it and replace with a new filter.
Filters WILL be damaged by sand / coins / keys / zippers / mobile phones / other random items in pockets or handbags. They're also damaged by moisture and Lens Cleaning products.
And finally, here's a list of some so-called "sun filters" that are UNSAFE !
- Regular sunglasses. It doesn't matter if they cost $2 or $20,000. NONE of them are designed for directly viewing the Sun safely (the $20,000 sunglasses may even include a warning about not staring at the sun...).
- Any type of tinted or coloured glass, including beer bottles and wine bottles.
- Tinted windows in cars and other vehicles
- Tinted windows in buildings.
- Polarisers, Neutral Density Filters and other coloured or tinted filters for cameras or eyepieces.
- This includes the "sun filters", like the one shown here, supplied with old telescopes to attach to their eyepieces. These dangerous antiques are known to shatter suddenly during use -- causing instant permanent blindness to any eye looking through it. If you still have one then DISCARD IT!
- Any type of photographic film, exposed or not.
- All CD-ROMs, DVD-ROMs, Blu-Rays and floppy discs.
- Wine cooler bags, space blankets, foil emergency blankets, food wrappers, snack bags, all types of plastic sheets (including aluminised Mylar), and plastic containers or plastic lids.
- Cloud in front of the Sun.
- A flat surface of water or glass reflecting the Sun's image.
- Any welder's eyeshield that's lighter than Grade 12. Most auto-darkening eyeshields and oxyacetylene welding eyeshields only go to Grade 11, at most.
- ...and Great-Granddad's favourite, a piece of Smoked or Sooty Glass.
The damage to your eyesight from unsafe viewing of the Sun is painless, because your eyeball contains no pain nerves. But the damage is PERMANENT and IRREVERSIBLE.
Your camera will need to be protected by a solar filter at all times -- except during the brief moments of total eclipse. The solar filter should be removed during total eclipse otherwise your camera won't be able to see it. Then as soon as the total eclipse ends, the solar filter needs to go back on your camera. Or you can use two cameras: one without a filter to be used only during total eclipse, and one with a filter to be used at all other times. The un-filtered camera needs to be fitted with a lens cap, or pointed away from the Sun, when it's not total eclipse.
There will be lots of beautiful photos posted online by experienced eclipse photographers afterwards. Who are using thousands of $$$ of equipment and taking multitudes of fully automated and pre-rehearsed exposures. Afterwards these photographers spend hours on their computers, processing & compositing these multiple images into "a total eclipse photo". Some of these composite images will get close to what your eyeballs can see directly.
Some of these experienced photographers have posted detailed eclipse photography advice here and here and here and here. You can also download a copy of Sky and Telescope magazine's 2023 eclipse photography article (PDF).
You will need to have full manual control of every aspect of your photos / videos to get good images. Auto-focus, auto-exposure time, auto-zoom, auto-ISO, etc are generally useless for eclipse photography; because the "auto-..." was designed for photos of scenery or people, not for astronomy. Another challenge for total solar eclipse photographers is the enormous brightness range of the solar corona; from "as bright as a full moon" nearest the (eclipsed) Sun, fading to the same brightness as the deep twilight of the total eclipse sky. You won't capture all of it in a single image; you will need multiple exposures at varying settings to be composited later. If your camera can do Exposure Bracketing then use it for each photo too.
Also, don't use Digital Zoom unless you want your eclipse close-up to look like a 1980s arcade game. You need genuine optical zoom or optical magnification. Many mobile phone cameras do Digital Zoom only.
Good digital cameras will allow you to selectively turn off their auto-features and manually control everything. Even cheap pocket digital cameras (and most mobile phone camera apps) will let you manually specify some settings, such as exposure times and ISO sensitivity. For recent model mobile phones, you can manually focus their standard camera app by pressing a fingertip to the exact part of the image you want to focus (such as the Moon's edge). Then tap the part of the image you're interested in to adjust the exposure time. If you're attempting a video of total eclipse, you will definitely need to manually control all settings, and be prepared to vary them.
If you're doing a time lapse of the eclipse remember that the Sun moves approximately its own diameter every two minutes. So from the beginning of partial eclipse through total eclipse to the end of partial eclipse it's going to move through about 30 degrees. Is your camera's view of this 30 degrees of sky going to be obstructed by trees, buildings, terrain, or late-arriving dimwits who park themselves between you and the eclipse? If it's an early morning or late afternoon eclipse then the horizon may interrupt the event anyway -- but also provide opportunities for wide-angle "eclipse over landscape" or "eclipse next to landmark" photos and time lapses.
To get an estimate of how big 30 degrees is, spread out your fingers and thumb at arm's length. For most people the angle between their outstretched little finger's tip and their outstretched thumb tip is about 15 degrees.
If you're using a zoom lens and/or a manual focus lens, be aware that zoom/focus settings may "creep" if the camera is pointed high in the sky, due to the weight of the lens. Use sticky tape to hold the zoom/focus controls in place, if they can't be locked.
If you’re still wanting to photograph the eclipse, practice practice, and practice, before eclipse day:
If this is your first solar eclipse then take a few photos of it if you want,
but don’t waste your time trying to get that perfect photo of total eclipse.
LOOK at it with your eyes instead.
but don’t waste your time trying to get that perfect photo of total eclipse.
LOOK at it with your eyes instead.
There will be lots of beautiful photos posted online by experienced eclipse photographers afterwards. Who are using thousands of $$$ of equipment and taking multitudes of fully automated and pre-rehearsed exposures. Afterwards these photographers spend hours on their computers, processing & compositing these multiple images into "a total eclipse photo". Some of these composite images will get close to what your eyeballs can see directly.
Some of these experienced photographers have posted detailed eclipse photography advice here and here and here and here. You can also download a copy of Sky and Telescope magazine's 2023 eclipse photography article (PDF).
You will need to have full manual control of every aspect of your photos / videos to get good images. Auto-focus, auto-exposure time, auto-zoom, auto-ISO, etc are generally useless for eclipse photography; because the "auto-..." was designed for photos of scenery or people, not for astronomy. Another challenge for total solar eclipse photographers is the enormous brightness range of the solar corona; from "as bright as a full moon" nearest the (eclipsed) Sun, fading to the same brightness as the deep twilight of the total eclipse sky. You won't capture all of it in a single image; you will need multiple exposures at varying settings to be composited later. If your camera can do Exposure Bracketing then use it for each photo too.
Also, don't use Digital Zoom unless you want your eclipse close-up to look like a 1980s arcade game. You need genuine optical zoom or optical magnification. Many mobile phone cameras do Digital Zoom only.
Good digital cameras will allow you to selectively turn off their auto-features and manually control everything. Even cheap pocket digital cameras (and most mobile phone camera apps) will let you manually specify some settings, such as exposure times and ISO sensitivity. For recent model mobile phones, you can manually focus their standard camera app by pressing a fingertip to the exact part of the image you want to focus (such as the Moon's edge). Then tap the part of the image you're interested in to adjust the exposure time. If you're attempting a video of total eclipse, you will definitely need to manually control all settings, and be prepared to vary them.
If you're doing a time lapse of the eclipse remember that the Sun moves approximately its own diameter every two minutes. So from the beginning of partial eclipse through total eclipse to the end of partial eclipse it's going to move through about 30 degrees. Is your camera's view of this 30 degrees of sky going to be obstructed by trees, buildings, terrain, or late-arriving dimwits who park themselves between you and the eclipse? If it's an early morning or late afternoon eclipse then the horizon may interrupt the event anyway -- but also provide opportunities for wide-angle "eclipse over landscape" or "eclipse next to landmark" photos and time lapses.
To get an estimate of how big 30 degrees is, spread out your fingers and thumb at arm's length. For most people the angle between their outstretched little finger's tip and their outstretched thumb tip is about 15 degrees.
If you're using a zoom lens and/or a manual focus lens, be aware that zoom/focus settings may "creep" if the camera is pointed high in the sky, due to the weight of the lens. Use sticky tape to hold the zoom/focus controls in place, if they can't be locked.
If you’re still wanting to photograph the eclipse, practice practice, and practice, before eclipse day:
- Use the Moon as a practice target during the weeks before eclipse day. Experiment with different lenses & exposure settings to get an idea of image size and exposure settings and exact manual focusing on your camera. If you have a safe solar filter for your camera you can also use the Sun as a practice target, and experiment with the correct exposure settings for the partial moments of the eclipse.
- If you're planning to do time lapse or a complex image sequence, it's well worth doing a practice run of the same duration using the Moon as target. You do not want to discover readily avoidable technical problems on eclipse day; such as insufficient battery life or too-small memory card or The Tripod Falls Over....
- Unless you're a Living Statue you will need to put your camera on a tripod; and use either a Cable Release or your camera's Shutter Delay feature (to avoid vibration caused by you pressing the shutter button). And will you still be a Living Statue during the excitement of total eclipse?
- If you don't have a tripod try using very short exposures combined with a high ISO to "freeze" any camera vibration. Or activate your camera's Shake Reduction / Image Stability feature if it has one. Either of these techniques is also useful for reducing any vibration due to wind.
- The ambient lighting during total eclipse is similar to a clear evening twilight 20-30 minutes after sunset. Try practicing with your equipment during twilights prior to eclipse day. In particular, learn how to operate your equipment without shining a bright light onto it to read buttons / switches / dials etc. Bright lights during a total eclipse are unwelcome.
- Practice quickly removing the solar filter from your camera (to photograph total eclipse) and quickly replacing it again (after the total eclipse). Or use two cameras, one without a filter (exclusively for total eclipse) and one with a filter.
- Bring spares of crucial items, such as fully charged batteries, memory cards or remote Cable Releases. Before eclipse day, practice quickly swapping "dead" crucial items for fresh ones.
- If you're using a mobile phone camera, do you have a fully charged battery and enough unused internal memory space to store your photos/videos? Don't expect to be able to upload to any kind of online storage in real-time. The mobile phone networks (if they even exist where you're viewing from) will be overloaded on eclipse day.
- If your photo equipment breaks during the eclipse don't waste time trying to fix it. It's better to abandon your photo efforts and simply enjoy the eyeball view.
- And don't spend the entire total eclipse duration looking at your camera. Look up and use your eyeballs too.
An example of pre-eclipse practice photography:
And before you start any photography on eclipse day...
TURN YOUR CAMERA’S FLASH OFF!
IF YOU CAN'T TURN THE FLASH OFF, THEN COVER IT UP!!
A mobile phone camera flash or a pocket camera flash is easily covered by a blob of Blu Tack -- which is available from practically every supermarket, hardware and office supply shop in Australia.
Or you can use electrical tape, if you don't mind cleaning tape glue off your phone afterwards.
During the dim light of a total eclipse, firing a camera flash towards people's eyes (even by accident)
is guaranteed to make you the target of verbal abuse from angry witnesses.
(and using a bright torch for any reason during a total eclipse is also unwelcome)
And WHAT do you think your camera flash is going to illuminate anyway?
The Moon is about 380 thousand kilometres away.
The Sun is about 150 million kilometres away.
The effective range of a camera flash is about 10 metres....which is useless for scenery or landscape photos.
And if the camera thinks the flash is "on", then it will default to an exposure time that's too short to actually photograph the total eclipse.
DON'T USE A CAMERA FLASH OR OTHER BRIGHT LIGHTS DURING A TOTAL ECLIPSE!
And before you start any photography on eclipse day...
TURN YOUR CAMERA’S FLASH OFF!
IF YOU CAN'T TURN THE FLASH OFF, THEN COVER IT UP!!
A mobile phone camera flash or a pocket camera flash is easily covered by a blob of Blu Tack -- which is available from practically every supermarket, hardware and office supply shop in Australia.
Or you can use electrical tape, if you don't mind cleaning tape glue off your phone afterwards.
During the dim light of a total eclipse, firing a camera flash towards people's eyes (even by accident)
is guaranteed to make you the target of verbal abuse from angry witnesses.
(and using a bright torch for any reason during a total eclipse is also unwelcome)
And WHAT do you think your camera flash is going to illuminate anyway?
The Moon is about 380 thousand kilometres away.
The Sun is about 150 million kilometres away.
The effective range of a camera flash is about 10 metres....which is useless for scenery or landscape photos.
And if the camera thinks the flash is "on", then it will default to an exposure time that's too short to actually photograph the total eclipse.
DON'T USE A CAMERA FLASH OR OTHER BRIGHT LIGHTS DURING A TOTAL ECLIPSE!
All of the solar and lunar eclipses listed on this website have the correct Australian local dates and times.
Also we live in Australia, so we know all about Australia's three major time zones, and the several smaller official (and unofficial) local time zones such as "Eucla Time". Plus which Australian states and territories use Summer (or Daylight Saving) time, and when.
Astronomers identify a solar eclipse by the date and time when the axis of the Moon's shadow passes closest to the Earth's centre. Similarly, a lunar eclipse's date and time is when the centre of the Moon passes closest to the axis of the Earth's shadow. Astronomers normally describe these moments using Universal Time, which is many hours different from all Australian time zones. For example the November 2012 total solar eclipse was officially defined to occur at about 22:13 on 13 November 2012, in Universal Time. But in northern Queensland it was the morning of 14 November.
Lunar eclipses, of course, can begin before local midnight and end after local midnight...and thereby even begin and end in different months like the Jan-Feb 2037 total lunar eclipse.
As for the exact times of when eclipses begin and end:
Meanwhile there's an old saying among experienced eclipse observers:
"All total solar eclipses, regardless of their predicted duration, always seem to be over in 10 seconds..."
Also we live in Australia, so we know all about Australia's three major time zones, and the several smaller official (and unofficial) local time zones such as "Eucla Time". Plus which Australian states and territories use Summer (or Daylight Saving) time, and when.
Astronomers identify a solar eclipse by the date and time when the axis of the Moon's shadow passes closest to the Earth's centre. Similarly, a lunar eclipse's date and time is when the centre of the Moon passes closest to the axis of the Earth's shadow. Astronomers normally describe these moments using Universal Time, which is many hours different from all Australian time zones. For example the November 2012 total solar eclipse was officially defined to occur at about 22:13 on 13 November 2012, in Universal Time. But in northern Queensland it was the morning of 14 November.
Lunar eclipses, of course, can begin before local midnight and end after local midnight...and thereby even begin and end in different months like the Jan-Feb 2037 total lunar eclipse.
As for the exact times of when eclipses begin and end:
- For lunar eclipses we only calculate starting and ending times to the nearest minute. The Earth's shadow edge upon the Moon is blurry because the Earth's atmosphere absorbs and scatters sunlight into and around the shadow. So any point on the Moon's surface will take many seconds to pass through the shadow's blurry edge from sunlight to eclipsed. Therefore in our opinion the "shadow edge" for lunar eclipses is a semantics problem as well as a mathematical problem.
Anyone predicting lunar eclipse times to the nearest second should also be mentioning which of the different mathematical approximations of the Earth's shadow they're using in their calculation. - It is essential to consider the Earth's gradually slowing rotation rate in eclipse calculations. This slowdown in rotation is mostly due to tidal forces from the Moon and Sun, plus some long-term geological phenomena. This leads to a difference between the time measured by modern atomic clocks (assumed to be unvarying) and the time measured by the Earth's rotation (Universal Time + your time zone offset, used for everyday life). But the slowdown rate is not constant. And it can change rate unexpectedly -- as it did during 2020-2023.
Astronomers describe the difference as the Delta-T parameter (ΔT); expressed in seconds of time. In everyday life the difference is managed using leap seconds. Delta-T can be calculated for past years from historical observations, but forecasting Delta-T for future years requires various assumptions. And the forecasting becomes increasingly unreliable as you go further into the future.
An error in the (predicted) Delta-T will displace a solar eclipse in longitude; and can change eclipse event times by many seconds especially for locations near the edges of a total eclipse path. For example if Delta-T for the 25 Nov 2030 eclipse is one second less than predicted, then the eclipse path through South Australia shifts almost 400 metres eastwards.
Anyone predicting solar eclipse events to the nearest second (or better) should be mentioning their chosen Delta-T value. - Since the 1990s there have been several improvements in mathematically describing the precise motions of the Earth, Sun. Moon and planets with a series of electronic ephemerides. So anyone predicting solar eclipse events to the nearest second (or better) should also be mentioning their chosen ephemeris. Differences between ephemerides can shift the eclipse path for many kilometres in any direction.
- Eclipse calculations are much easier -- but less accurate -- if the Earth and Moon are both assumed to be smooth spheres devoid of any topography. This greatly reduced the arithmetical tedium before the advent of electronic computers; and many eclipse apps and websites still do it for the sake of speed and programming simplicity. The reputable calculators that do this will also include disclaimers like "observer is assumed to be at sea level" and "no corrections for lunar limb outline" or similar wording. But their results (as intended) are good enough for planning your eclipse trip.
We've done the more difficult -- but more accurate -- additional calculations to get our total solar eclipse times to 0.1 second accuracy, after correcting for:- The Moon's actual topographic outline at the time of eclipse (the lunar limb profile), and
- Australia's own topography (local terrain), and
- Atmospheric refraction for all eclipse events happening less than 15 degrees above the horizon.
Topography corrections also shift the maximum eclipse duration away from the geometric centre of a total eclipse path.
Just to make the problem even more difficult, the Moon "wobbles" (librates) as it orbits the Earth, so its exact outline is always changing. Fortunately the wobbling can be accurately predicted in advance.
Serious attempts to correct eclipses times for the Moon's topography began in 1963, based on photographs (from Earth) of the edges of the Moon. These Watts Charts were used for the next 45 years, until laser altimeter data and high-definition TV images of the entire Moon from Japan's SELENE ("Kaguya") lunar orbiter were published. Also in 2009, the USA's Lunar Reconnaissance Orbiter began its own high-resolution mapping and laser altimetry of the entire Moon. Thanks to these two missions we now have very detailed topographic maps of the Moon and can calculate its actual outline during a solar eclipse. In fact we have better maps of the Moon nowadays than we do of the Earth's deep ocean floors.
Dedicated Radar Topography satellite missions orbiting Earth since the 1990s have also yielded detailed topographic maps of Australia, allowing corrections for your altitude. Generally these terrain corrections are small because 99 percent of Australia is less than 1000 metres above sea level. But (again) if you're near the edge of the path, being on top of a mountain may lift you into the Moon's shadow. Or it might lift you out of the shadow.
One of the largest remaining causes of solar eclipse inaccuracy is that we don't know the precise diameter of the Sun, nor if it's constant. And some astronomers still disagree about what we're defining to be "the surface" of the Sun. We adopted a mean solar radius of 960.0 arcseconds for our calculations. - Solar eclipse timings for cities will depend on the definition of their geographic location, and that location's height above sea level. Is there a distinct city centre? If the city centre is clearly offset from the centre of population (for example Sydney) should you be using the latter instead? Does a total eclipse that includes suburbs, but misses the city centre, still count as "total" for that city?
- For partial solar eclipse events we only calculate the times to the nearest second. There's no point being any more precise because "the Sun's disc 1 second after the eclipse starts (or ends)" looks practically the same as it did 2 seconds earlier. The beginning of a partial eclipse normally isn't noticeable for a few seconds anyway, unless you're observing the exact point on the Sun's edge at high magnification. It's easier to spot the moment when a partial eclipse ends.
- If an eclipse is in progress at sunrise its "starting time" is set equal to sunrise time. Similarly if an eclipse is in progress at sunset then it "finishes" at sunset time. Sunrise and sunset times are only calculated to the nearest minute. Calculating the exact time to the second would require measuring the atmosphere's complete temperature and pressure profile, between the Sun and the observer, to then calculate the true atmospheric refraction for that instant for that observer. It's much easier to assume a Standard Atmosphere Profile whose refraction is already known -- and which we've included in our calculations.
Meanwhile there's an old saying among experienced eclipse observers:
"All total solar eclipses, regardless of their predicted duration, always seem to be over in 10 seconds..."
There are three views of each map area. All three views show:
The differences between each view are:
The road graphs plot driving distance in kilometres along a road -vs- the duration in seconds of total solar eclipse.
The durations were calculated for hundreds of points along each road, fully corrected to 0.1 second accuracy as described above. Driving distances between points were also corrected for any changes in height. An identifiable location (usually a road intersection) is chosen as zero km. Reset your vehicle's trip meter at this location and start driving to your chosen spot. No need for a GPS or navigation app. The graphs include road intersections and other identifiable features as a distance check. Graphs for straight roads that cross the eclipse path will resemble the expected near-semicircle. Graphs of roads that parallel the eclipse path will be almost "flat". Meandering roads will have more complex graphs.
The graphs also show how many kilometres of the road gets a similar duration as the centre line. If centre line is unreachable or too crowded on the day, find another spot along the road that's just as good.
We don't offer interactive maps or calculators because they're vulnerable to abuse by web bots that try to harvest predictions for thousands or millions of locations per eclipse. These attacks slow down the website for everyone else and add huge $$ to our internet costs.
- The total eclipse path as a dark band across the map, with a purple Centre Line and two purple boundaries (North limit and South limit). You will need to be inside this dark band to see a Total Solar Eclipse.
If you're less than two kilometres outside the purple boundaries you will see a "Beaded" eclipse.
Everywhere else on the maps sees a Partial eclipse. - Some of the towns within and near the total eclipse are labelled, for easier comparison of these maps with your other maps.
- The roads which feature in the duration graphs are highlighted and labelled. Dark pink for sealed roads, dark orange for unsealed roads.
- Times and durations and contours are fully corrected to 0.1 second accuracy as described above. Interpolate for your location, if it's not already included in the lists of eclipse times.
The differences between each view are:
- First view shows total eclipse duration contours (in seconds) as dashed purple lines, and partial eclipse obscuration percentages as dashed blue lines.
- Second view show the (local) starting time of the total eclipse, using contours at 10 second intervals.
- Third view show the (local) ending time of the total eclipse, using contours at 10 second intervals.
The road graphs plot driving distance in kilometres along a road -vs- the duration in seconds of total solar eclipse.
The durations were calculated for hundreds of points along each road, fully corrected to 0.1 second accuracy as described above. Driving distances between points were also corrected for any changes in height. An identifiable location (usually a road intersection) is chosen as zero km. Reset your vehicle's trip meter at this location and start driving to your chosen spot. No need for a GPS or navigation app. The graphs include road intersections and other identifiable features as a distance check. Graphs for straight roads that cross the eclipse path will resemble the expected near-semicircle. Graphs of roads that parallel the eclipse path will be almost "flat". Meandering roads will have more complex graphs.
The graphs also show how many kilometres of the road gets a similar duration as the centre line. If centre line is unreachable or too crowded on the day, find another spot along the road that's just as good.
We don't offer interactive maps or calculators because they're vulnerable to abuse by web bots that try to harvest predictions for thousands or millions of locations per eclipse. These attacks slow down the website for everyone else and add huge $$ to our internet costs.
Every eclipse website gets huge increases in traffic on the actual days of eclipses:
The reputable websites include:
- Astronomical Society of Australia's Solar Eclipse site.
- American Astronomical Society's eclipse site. Not just for USA eclipses; there's a lot of excellent general eclipse information and advice too.
- Besselian Elements, a deep dive into the technical details of eclipses.
- Eclipse Atlas, a huge online gallery of historic and modern eclipse maps.
- Eclipse Chasers, but use their site search box.
- Eclipse Maps -- past present and future.
- Eclipsewise eclipse maps, animations, predictions, data and advice; by the late great Fred Espenak.
- Eclipsophile eclipse weather and climate forecasting.
- International Astronomical Union's Working Group on Solar Eclipses. Links to a vast collection of eclipse resources for professional astronomers and for the general public.
- NASA's eclipse website (if the US Government shuts this down or stupid-ifies it, try one of its pre-2025 versions at Internet Archive.)
- Oz Eclipse, another Australian solar eclipse website. We love his portable quick-remove solar filter design.
- timeanddate.com don't just do time conversions and calendars. They also do eclipse maps, animations and predictions.
- Xavier Jubier's interactive Google Maps of eclipses. You will need an internet connection for the real-time interactive features to work.
- Yuk Tung Liu's eight millennia of eclipses includes maps and detailed eclipse circumstances for all solar and lunar eclipses between 4000 BCE and 4000 CE.
