Welcome to September, Stargazers! To be honest, August is a hard celestial act to follow but the September night sky allows to to focus in on events that might have otherwise been overshadowed if they had occurred in another month. September stargazing gets back to the basics of stargazing, moon-watching and planet-peeping (few and far between). September is a return to grassroots stargazing, if you will. For this reason, September is a great month to get into stargazing; plus the nights are getting longer meaning more time to observe the wonders of our universe. So please read ahead at your leisure to find out more about the grassroots, locally sourced, farm-to-table celestial patterns and objects to gaze at this September. (Extended metaphor anyone?)
Love is in the air? More like love is in the dark vacuum of space! Astronomers use the term “kissing” to refer to the appearance that two planetary bodies touch. They don’t of course; if planets touched it would be less of a kiss and more of a world-ending, high-speed collision. But from our vantage point on earth we can witness planets and moons appearing so close they touch, or “kiss”. There are a couple examples of this throughout September, with most lying in the southern hemisphere. However if you have a telescope you can see one from Ireland:
Neptune Kisses Phi Aquarii
Tonight, Friday 6th September, you should face between south and southeast of the night sky with a telescope and witness our furthest neighbour Neptune coming within one arc-minute of the star Phi Aquarii. If you do have a telescope you should also see if you can see Neptune’s large moon Triton!
Coming into the autumn months there are some great star patterns to look out for. The first to note is Pegasus! To find Pegasus in the night sky, face roughly south.
According to myth and legend, Pegasus was the winged horse belonging to the demi-God Hercules. On a gory note; the myth goes that Pegasus and his brother Chrysaor were born from the streaming blood around Medusa’s neck when Perseus beheaded her. Yikes. Thankfully, this is not what you can see in the sky. Pegasus is a helpful pattern to get used to finding as the central square region (aptly named, The Great Square) helps you find out just how much light pollution you have by the number of stars visible. If you can’t see any then your area suffers from quite a bit of light pollution.
If you move along the back leg of Pegasus toward the East you will come to an interesting object that you’ll be able to see in an area with very little light pollution. It may resemble a smudge in the sky, a little puff of cloud or as if Pegasus was vaping in the sky above your head. It’s actually a galaxy called Andromeda!
Andromeda is our neighbouring galaxy; it’s the closest major galaxy to us besides the large and small Magellanic clouds. It has twice the stars that our own Milky Way galaxy has at about one trillion! Andromeda is beautiful, wouldn’t you agree?
Well I’m glad you think so because someday it will be a lot closer. Andromeda is currently hurtling towards us at a speed of 68 miles per second. In fact, in about 4.5 billion years Andromeda will collide with the Milky Way to form one larger galaxy: Milkomeda! NASA have created a video of how this collision will look from an outside perspective:
No need to be alarmed however: the stars in both galaxies are so far apart that it’s improbable any will collide. That piece of information underscores just how empty space is. However, this shouldn’t be a concern, it’s quite a while away and it’s not very likely that humans will still be on earth at the point. So, since no one can see it for real, here’s an artist’s impression of what the two galaxies combined may look like.
I would advise you to gaze skywards the night of September 8th (this Sunday) to see two of the moon’s largest craters; Tycho and Copernicus. Not just AOP function room namesakes, these two craters are poised to be ogled at as the terminator is nearby, providing them with ideal lighting. If the moon could take selfies, this would be the night.
Tycho is a huge 4,800 metres deep, whilst Copernicus is 3,800 metres deep.
So stargazers, that’s it for this month. These are a few of the highlights but there are many constellations to observe this time of year, and with the longer nights there couldn’t be a better time to give star gazing a go. Fingers crossed for clear skies!