Shooting stars, Supermoon Total Eclipse & Mercury in May '21
May 2021 will be an interesting one for fans of astronomy in Australia, including the Eta Aquariids Meteor Shower, a total lunar eclipse producing a blood moon during the supermoon and mercury at its highest point in the western sky. So watch the skies at night for some great events this month.
Eta Aquariids Meteor Shower can produce up to 60 shooting stars an hour at its peak, especially here in Australia as the southern hemisphere gets a much better view than the northern part of the world. The meteor shower runs from April 19 to May 28, but the peak will be on the evening of May 6 and the morning of May 7, with the best viewing times between midnight and the dawn's first light on the 7th. Though with the quarter moon rising a couple of hours after midnight, you will want to focus on the time from midnight to moonrise for your sky watching.
A picture of an Eta Aquarids shooting star courtesy of Jeff Sullivan @ flickr
A few notes on the Eta Aquariids meteor shower. It is created by the dust from Halley's Comet. To view the shooting stars, you want to go to a dark location, so far away from the city, such as a remote beach or bushland area with little to no urban light pollution. The name of the meteor shower comes from the radiant point, which is the constellation Aquarius, but the shooting stars will spread out over the night sky. But remember, if you are watching at close to midnight, look mostly towards the eastern sky.
Image of Halley's Comet, the source of the Eta Aquariids meteor shower courtesy of NASA
For people with telescopes, Wednesday May 12 is when no moon will be visible in the night sky. With no moonlight blocking out fainter objects, it is a great time to point your telescope at the harder to see dim objects in the sky.
Between May 17 and May 24, you will have a good opportunity to view Mercury. This planet, from which we get the term Mercurial, lies between the Earth and the sun, often it is not visible at night. On May 17, Mercury will be at its Greatest Eastern Elongation. This is when it is furthest to the side of the sun from the Earth's perspective. But it will actually be at its highest above the horizon on May 24. To view Mercury, look to the western sky just after sunset. It should be the first "star" visible as the sky darkens.
Mercury can be seen just after sunset on in the Western sky in May
For keen observers of astronomical phenomenons, on May 23, Saturn will begin its retrograde motion. This apparent reversal of its path in the night sky is due to the relative motions of Earth and Saturn. The result will be 2 conjunctions between the moon and Saturn in May, the first on May 4, and the second on May 31, when these 2 celestial objects will appear in the sky together.
The second supermoon of the year will occur on May 26. While Supermoons are meant to brighter than normal moons, this time, here in Australia, the corresponding total eclipse of the moon will result in 5 hours of the supermoon being not only dimmer than normal but actually going blood red during the eclipse.
There is a lot of confusion in the media about supermoons. First of all, much of the media like to report names like Pink Supermoon (for April) or I am sure they will call this one a Flower Supermoon or maybe even the Corn Planting Supermoon. These are the traditional names for one part of North America. Given that it is Autumn in Australia, not spring, using a name associated with the North American spring is incorrect. Luckily though they are likely to get the date correct. Often in Australia, we get the Supermoon on the day after North America, but this time it will be on the same day. This is a combination of things like international datelines and the time that moon passes the meridian that makes the difference to the specific date, and the date of the supermoon can differ between countries.
The moon will rise before sunset and set after sunrise. There are lots of great supermoon activities, including romantic walks on the beach under the moonlight, hiking by moonlight and of course, there is moon photography. But factor in the lunar eclipse into this though.
But this supermoon will be more than just a supermoon. Here in Australia, we will get a blood supermoon as a total lunar eclipse will occur. Because this eclipse will occur when the moon is closest to the Earth, the Earth's shadow won't completely block out all light, but instead, turn the moon a dark red as the light going through the Earth's atmosphere will still fall on the moon, which is reddish.
A blood moon is aptly name, as it transitions to a dark red colour during the eclipse
Australia will get a great view, with the full lunar eclipse process, being visible across most of the country, while Perth and much of the West Coast of Australia seeing the moon already slightly darkened, but not red yet when it rises. The Exmouth region, because they are so far west, will see the moon rise already eclipsed.
In terms of the timing, the first part of the eclipse starts at 8:47 Coordinated Universal Time, with the full eclipse starting at 11:11 Coordinated Universal Time. This translates to 9:11 pm on the East Coast of Australia for the start of the full eclipse. In Perth that is 7:18 pm and in Adelaide it is 8:48 pm. Overall the time for the total eclipse phase is only 15 minutes, but the moon starts dimming and remains dim for about 5 hours in total.
You should be able to view the eclipse from anywhere that you can see the moon, which includes the city as well. Certainly, people in the suburbs will have a good view without needing to go out to the countryside. The moon will also be up far enough by that time that it should be able to be seen from people's backyards. Though of course, a park will give you a clearer view.