Extract from ABC News
Only a handful of meteors will be visible each hour during this year's Eta Aquariids because of the Moon. (Wikimedia Commons: Kulish Kateryna, CC BY 4.0)
The beginning of May heralds the peak of the annual Eta Aquariids meteor shower.
The Eta Aquariids usually put on a good show, but this year they peak a few days after a full moon so they will be much harder to see than usual.
If you are really keen, you still may catch a few fireballs if you're awake before sunrise on May 6 and 7.
Tanya Hill, an astronomer at the Melbourne Planetarium, says the Eta Aquariids do not produce many meteors that are bright enough to beat glare from the Moon.
"Under ideal conditions you'd expect 20–30 meteors an hour, in the hour before dawn, but the Moon drops this right down to only about 5–10," Dr Hill says.
Here's what you need to know if you are determined to spot a meteor or two.
If you don't want to take a chance, the good news is that there are other things to see in the sky this month including a comet, two planets drawing closer together, and a "blue" micromoon.
And you don't need to be up at 4am to see any of these.
Eta Aquariid meteor shower
In early May each year, Earth passes through a dust trail left behind by Halley's Comet, leading to a meteor shower as pieces of dust burn up in our atmosphere.
From the ground, the meteors look like they're coming from near the star Eta Aquarii in the constellation Aquarius above the north-eastern horizon.
Meteors appear to be coming from the same point in the sky during these showers — a "radiant point". (Wikimedia: Hao Yin/CC BY 4.0)
The higher this "radiant point" is in the sky, the more meteors you'll see. But the radiant point doesn't rise until after midnight local time, and reaches its peak when the Sun has risen.
That's why best viewing for this shower is usually an hour or two before dawn, when the radiant point is high but the Sun's light hasn't yet drowned the meteors out.
Some estimates posted online suggest the shower could have up to 50 meteors an hour, but these predictions are far too optimistic even under the darkest conditions in Australia.
Jonti Horner, an astrophysicist at the University of Southern Queensland, says these estimates come from the "zenithal hourly rate", or ZHR, which is used by astronomers to compare meteor shower strength.
"That's an estimate of the number of meteors that you would see if you had perfect conditions, perfectly dark skies, perfect eyesight, and – this is a key point – the radiant was directly overhead," he says.
This year, the meteors have to compete with light from a waning gibbous moon from the time the radiant rises, so the number you can see will be much lower than usual.
Halley's Comet's dust trail intersects the Earth's orbit in early May and late October each year. (Supplied: NASA/SSD/Jacinta Bowler)
Professor Horner says it's still worth keeping an eye out for meteors if you happen to be up before dawn anyway.
"If you've got to be at work before dawn, take your coffee outside, sit down, wrap up warm," he says.
"You may as well watch, because there will be something to see if you watch for long enough."
If you miss them, there's always next year.
And there won't be a pesky moon to get in the way, Dr Hill says.
"It will be much better to wait until next year, when the new Moon occurs on May 6 and the sky will be lovely and dark."
If you can't wait that long, Australia's best meteor shower, the Geminids, will be moon-free in December.
Comet PanSTARRS a boon for binoculars
The comet C/2025 R3 PanSTARRS is glowing in western skies just after sunset at the moment, having completed its slingshot around the Sun in late April.
The blue-green coloured comet is currently magnitude 5.2, which means it is visible under dark sky conditions.
Professor Horner says it's "borderline" whether you will be able to see the comet with the naked eye, but it would be good to look for with binoculars.
Astrophotographers, such as Ron Webb, recently captured long-exposure shots of the comet with a high-end DSLR camera and zoom lens.
Other astrophotographers are capturing the comet in more detail with small telescopes.
Venus and Jupiter coming close
The planets Venus and Jupiter are also in the evening skies at the moment.
"Venus is really bright in the western sky after sunset now," Professor Horner says.
"It looks like an aircraft coming in with its headlights on."
Jupiter, higher in the north-west after sunset, appears to be approaching Venus from our perspective at the moment.
Jupiter and Venus will be the brightest objects in the night sky when they're close together in early June. (Flickr: FolsomNatural)
Professor Horner says it's worth watching the planets over the next six weeks as they approach.
"Venus and Jupiter will swing past each other around 9–10 June … and then you'll get a real feel for how much brighter Venus is than Jupiter."
The Moon will be below the horizon by this point, making the two planets the brightest things in the night sky.
A 'blue' micromoon at the end of May
May opened with a full moon on May 2 (aka the Flower Moon) and closes with a second full moon on May 31.
The second full moon in a calendar month is known as a "blue" moon. (It has nothing to do with the colour of the Moon.)
Since the Moon takes 29.5 days to completely circle the Earth, blue moons are relatively uncommon, happening roughly once every 2.5 years.
Both of May’s full moons will also be "micro full moons" according to some definitions: they’ll be full when the Moon nears its furthest point from Earth, or apogee.
The largest supermoon and the smallest micromoon would look different if sitting together, but on their own the difference is hard to spot. (NASA: JPL/Caltech)
This means they are the opposite of a super full moon, which occurs when a moon is full at its closest approach to Earth that month.
While they will appear smaller and less bright than the closest super full moons, the difference in both is hard to see.
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