There’s one thing fantastic about sitting below the night time sky, watching a meteor bathe play out overhead. Nevertheless, observers within the southern hemisphere normally get the brief finish of the stick, with a lot of the finest showers strongly favouring these north of the equator.
Each Could, nonetheless, southern observers get a particular deal with – the Eta Aquariid meteor bathe. This yr circumstances promise to be good, making it the perfect alternative for some autumnal meteor statement.
The forecast peak for this yr’s Eta Aquariids falls on the morning of Saturday, Could 7. The Moon is effectively out of the best way, so meteors gained’t be misplaced in its glare.
However what if skies are cloudy? Effectively, for those who miss the morning of the height, don’t panic! The Eta Aquariids are famed for his or her broad peak, and meteor charges sometimes keep excessive for a couple of week across the peak (Could 4–11). So if Saturday morning is cloudy, strive trying once more on Sunday, and even Monday.
To get one of the best view, you’ll wish to rise up within the early hours of the morning and be effectively away from any vivid metropolis lights. Give your eyes time to regulate to the darkness. Take a chair or recliner to get comfy, calm down and gaze skywards.
You gained’t even want a telescope! To finest observe meteor showers, you’ll wish to watch as extensive an space of sky as doable. Utilizing a telescope or binoculars would make the spectacle nearly unimaginable to watch.
Mud and particles from a well-known comet
Because the Earth orbits the Solar, it frequently runs into mud and particles from comets and asteroids. Each April and Could, the Earth spends about six weeks traversing a river of mud left behind by the well-known Comet 1P/Halley.
Comet 1P/Halley was photographed on March 8, 1986, throughout its final move across the Solar.
NASA/W. Liller
Each 76 years or so, Comet Halley swings near the Solar. Its icy floor heats up till the ices boil off into house in a course of known as “sublimation”. This shrouds the comet in a gaseous coma, which is blown away from the Solar to generate the comet’s tail.
The gasoline escaping Halley’s floor carries mud grains, which regularly unfold across the comet’s orbit. Some transfer forward of the comet, whereas others lag behind.
Over hundreds of years, the house round Halley’s orbit has turn into thick with mud grains. The comet is basically shifting via a unclean snowstorm of its personal making! And annually, the Earth runs via that broad river of mud – giving delivery to the Eta Aquariid meteor bathe.
Curiously, the Earth runs into Halley’s particles once more in October, producing the well-known Orionid meteor bathe. However we get a greater present in Could annually with the Eta Aquariids, as that is once we transfer nearer to the centre of the mud stream.
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The place ought to I look?
When mud left behind by a comet smashes into Earth’s ambiance, it turns into a spectacular fiery streak of sunshine excessive within the sky. This normally occurs about 80km above the bottom, though the biggest bits of particles can penetrate fairly deep into the ambiance earlier than burning up solely.
The mud grains in a meteor bathe all transfer across the Solar at basically the identical pace and in the identical route. This implies the grains are additionally travelling in the identical route as they hit the Earth.
However as they transfer in direction of an observer on the bottom, that observer’s perspective will make their paths diverge, and they’ll appear to be radiating out from a single level within the sky. That time is called a bathe’s “radiant”.
The Orionid meteors are a fantastic instance of how meteors in a bathe appear to radiate from a single level within the sky.
Phil Hart
Meteors showers are named for the constellation wherein their radiant lies. So the Eta Aquariids have a radiant close to the star Eta Aquarii – the tenth-brightest star in Aquarius.
To see the Eta Aquariids, you’ll want to attend till the radiant rises – earlier than that, the physique of the Earth will get in the best way. We’re fortunate right here within the southern hemisphere, because the Eta Aquariid radiant rises within the east at round 1:30 to 2am, native time.
The Eta Aquariids radiant will rise between 1.20am and a couple of.20am for cities throughout Australia.
Museums Victoria
Whereas the Eta Aquariid meteors will be seen anyplace within the sky, the perfect place to see one of the best variety of meteors is about 45 levels to the left or proper of the radiant itself.
Thankfully, this yr we have now one other spectacular sight within the morning sky. 4 planets – Saturn, Mars, Jupiter and Venus – will all be in a line. To see one of the best meteor present, look about 45 levels to the left or proper of this line of planets.
The road of planets and the Eta Aquariid radiant as they’ll seem at round 4am on Could 7 from Sydney (rising within the east). The sky will look largely the identical from Brisbane, Canberra and Perth at 4am (native time), Melbourne, Hobart and Adelaide at 4:30am (native time) and Darwin at 5am (native time).
Museums Victoria/Stellarium
To see how the planets and radiant will rise out of your location, go to the Stellarium planetarium web site, set your location and transfer the date and time ahead to the morning of Could 7. In the event you activate the “constellations” and “constellations artwork” (on the backside of the display screen), you may watch Aquarius and the planets rising from the consolation of your laptop.
What number of meteors ought to I count on to see?
The Eta Aquariids are the second finest bathe of the yr for folks in Australia. They’ll placed on a spectacular present – however don’t count on to see meteors falling like snowflakes.
When the radiant first rises above the horizon, at round 1.30am, meteors from the bathe can be few and much between. In the event you see 5 or 6 Eta Aquariids in that first hour, you must most likely depend your self fortunate.
That stated, these early meteors might be actually spectacular. Often known as “Earth grazers”, they typically appear to streak from close to one horizon all the best way throughout the sky. Earth grazers are the results of meteors hitting our ambiance at a really shallow angle, nearly edge on. They’re uncommon, however unbelievable to witness!
Because the night time goes on, and the radiant climbs increased into the sky, the variety of meteors ought to improve. Within the hour earlier than daybreak, you can simply see 20 to 30 meteors per hour.
Oh, and a phrase of warning: meteors are like buses – for those who’re anticipating 30 per hour, you may simply wait ten minutes and see nothing, earlier than three come alongside without delay. Be sure you gown heat so you may keep below the celebs for no less than half an hour, if no more!
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