“To find the universal elements enough; to find the air and the water exhilarating; to be refreshed by a morning walk or an evening saunter. To be thrilled by the stars at night; to be elated over a bird’s nest or a wildflower in spring – these are some of the rewards of the simple life.”
– John Burroughs, Leaf and Tendril
So, it feels like the year has only just started, but we are well into spring now and the weather is getting warmer every day. With the change of the clocks, we have longer evenings, which will encourage sitting outside and enjoying the natural world a bit more than we have over the past few months!
We can use the small and simple comfort of the night sky’s presence to guide us through the new month and make sure to take the opportunity to view plenty of spring constellations as they become visible at this time of year.
The first astronomical event of the month this year is the full moon. The full moon in May is known as the full flower moon, and certain parts of the world will even see a lunar eclipse this month! However, we here in the UK and Ireland are unfortunate enough to miss the eclipse completely if we stay at home. Feel free though to go on an eclipse viewing tour of the world – this one will be visible through most of Asia and Australia, Madagascar and the South Island of New Zealand/Aotearoa. Africa and most of Europe will see some of the eclipse at moonrise, but not the whole thing. We are simply too far west to see any of the eclipse here. It should be a nice event to see, but if you are stuck here in the no eclipse zone you may be luckier in October of this year, when the next lunar eclipse will occur.
Throughout the month of May we have a reasonably active meteor shower, though. The Eta Aquariids peak on the 6th and 7th May this year, but they carry on throughout the rest of the month at a slightly lower frequency. The conditions for viewing the meteor shower at its peak won’t be great – it is only a day or two after the full moon, and so the sky will be illuminated by the moon and the meteors will be harder to see. This means that even though the meteor shower peaks at the start of the month, you might be better off waiting a few days for the moon to wane to get a better view.
The Eta Aquariids shower appears to radiate from the constellation of Aquarius, and its parent body is the famous Comet Halley. As Halley soars through the solar system it leaves behind a trail of debris. Earth passes through this trail every year and the debris rains on the atmosphere, which we see as the Eta Aquariids meteor shower.
On the opposite side of the moon cycle, we have the new moon on the 19th of the month this year. This will be one of the darkest nights of the month so take the chance to do some stargazing while conditions are good.
If you read last month’s sky notes, you might have seen that Mercury was at its greatest Eastern elongation on the 11th of April. This month you will see the other side of the story, as Mercury will be at its greatest Western elongation on the 29th of May – this is the point when Mercury is at its highest above the horizon, and so is the best viewing opportunity. Mercury will be visible in the night sky just before sunrise. Because mercury is the closest planet to the sun, it never strays far from the sun in our sky. This means that elongations are the best time to view the planet, so take the chance to look at it while you can!
Some of the constellations that are visible in the spring night sky are well known, others are less well known. One of the constellations that you hear less about is Leo minor. It is certainly overshadowed by its older sibling, Leo the lion, which is one of the signs of the zodiac and therefore commonly seen in popular culture. Leo Minor though is a faint constellation, found between Ursa Major and Leo itself. Leo minor has a couple of interesting stars, including 46 Leonis Minoris, which is an orange giant star of magnitude 3.8. The lower the magnitude of a star, the brighter it is (a little counterintuitive) and some very bright stars even go into the negatives. Sirius, the brightest star in the sky, has a magnitude of –1.46.
Beta Leonis Minoris is another star in the constellation of Leo Minor, which is actually a binary star system, with two stars orbiting around each other. There is a brighter orange giant star twice the mass of our sun, accompanied by a fainter, yellow main sequence star.
But there are other, more interesting stars within this constellation. There are two stars in this area that have planetary systems around them. These exoplanets (planets outside our solar system) are very interesting to astronomers who want to see what else is out there and see if there could be other earth-like planets somewhere in our galaxy!
Other interesting objects in the constellation of Leo Minor are the deep sky objects. A deep sky object is any astronomical object that is not making up a solar system. Galaxies are common, as well as nebulae and star clusters. In Leo Minor there are a number of galaxies visible with a telescope, that amateur astronomers can look for and admire.
A deep-sky object that is great to look out for in the constellation of Leo Minor is the delightfully named Hanny’s Voorwerp. It is named for its discoverer, a Dutch schoolteacher, Hanny van Arkel, who was volunteering for a citizen science project when she spotted the quasar echo in a picture. You too may have a chance to discover something spectacular if you take part in citizen science projects – head to the Zooniverse web portal to find a project that interests you, just like Hanny van Arkel did.
So do take the opportunity of the (supposedly) better weather to do some stargazing, or even some moongazing this month. It’s a great time of year to be outside, as flowers bloom and birds start to sing. There’s lots to look out for, and not only in the sky this month!