How low can you go? Our challenge: find the most southerly object you can see
This month’s Deep-Sky Tour requires you to go low – down to southerly declinations that you probably wouldn’t think about wandering into under normal circumstances. And perfectly understandable that is too, since lowaltitude objects are compromised by the layer of thicker atmospheric murk which lurks near the horizon. But it is sometimes interesting to push your limits just to see how far south you can actually see from your own back garden or surrounding area. Your challenge this month is to see just how low you can actually go.
Yes, you can cheat for this and look at a planetarium program, but there’s something quite amazing about putting in the effort and navigating to southern declinations yourself. If you’re not overly familiar with the night sky, or perhaps not that familiar with the more southerly constellations, the challenge also adds a bit of celestial navigation into the mix and this is both useful and entertaining. If you don’t fancy standing out in the cold to do this, then consider taking a photograph of your southern horizon which you can study in comfort, inside in the warm.
What you can see will depend on what time you try, but we’d suggest starting out in the earlier part of the evening, say around 21:40 BST (20:40 UT) on 1 October, which equates to 20:40 BST (19:40 UT) on 15 October and 18:40 UT on 31 October. Looking south at this time will show you Saturn above the eastern section of the triangle of Capricornus. To the southeast of Saturn and very close to the south-southeast horizon, is bright, mag. +1.2 Fomalhaut (Alpha (α) Piscis Austrinus). If you can’t see this star, consider trying again from somewhere with a flatter southern horizon.
This challenge adds a bit of celestial navigation into the mix that’s both useful and entertaining
From Saturn and using our chart, try to make out the form of Capricornus, right down to mag. +4.1 Omega (ω) Capricorni. Now comes the interesting part. Using sections of Capricornus as a sky ruler, try navigating south from Omega Capricorni towards the small group of faint stars that forms the constellation of Microscopium: mag. +4.9 Alpha (α) Microscopii, mag. +4.7 Gamma (γ) Microscopii and mag. +4.7 Epsilon (ε) Microscopii.
If you live anywhere south of 53˚ north latitude, look out for a brief appearance of mag. +3.0 Gamma (γ) Gruis which is at its highest around 25 minutes after the stated times above. We’re stretching the meaning of ‘highest’ here though: when it’s due south from a location at 53N latitude, Gamma Gruis just scrapes the horizon! If you live anywhere in the UK and have seen this star, drop us a line saying where you were and what the conditions were like.
