By Niall Smith
The search for evidence of life beyond the Earth came a small step closer — perhaps — when NASA’s Curiosity Rover recently discovered organic molecules in a crater on Mars called Gale Crater.
Organic molecules are the building blocks of life as we know it.
They are not rare, being found even in meteorites that survive the burning passage through the Earth’s atmosphere. What makes the Mars discovery intriguing, however, is the location of the organic molecules.
While today Gale Crater is a barren wasteland, some 3.5 billion years ago it appears to have been a lake with rivers flowing in and out.
So we can imagine a lake in which both liquid water and organic molecules once existed side-by-side, for probably a billion years.
At the very least this was likely to have been long enough for some interesting chemistry to take place, and potentially might have spawned life.
Right now, we have no evidence for life on Mars and we may never find such evidence, but the results remind me of an Isaac Azimov quote: “The most exciting phrase in science is not ‘eureka! (I’ve found it)’ but ‘That’s funny…’.”
And this discovery is certainly ‘funny’ and merits further investigation.
You can catch a look at the Red Planet for yourself in July as Mars is well-placed in the morning sky. Due to the short nights you will have to get up early, or stay up late, whichever is your preference or lifestyle.
Mars is due south around 4am, but a handy way to find it is to look for a red object just below the Moon on July 1.
Mars’ characteristic red colour is due to a thin covering of rust which covers the entire planet, often being whipped up by planet-scale dust storms that dwarf anything we find on Earth.
Counterintuitively, the sunset or sunrise on Mars is blue, not red!
Unlike the dust in Earth’s atmosphere, which is just the right size to scatter blue light and allow red light to pass unscattered, the reverse is true on Mars where the dustier nature of the atmosphere scatters the red light.
At sunrise and sunset the effect is for the red light to be scattered away from your eyes and the blue light to be unscattered towards your eyes.
On July 27, around 9.30pm, the rising Moon will appear dimmer than usual and may have an eerie deep red colour to it.
The reason is that the Moon is about half way through a total lunar eclipse, a phenomenon that occurs when the Earth’s shadow blocks much of the Sun’s light from reaching the Moon.
The light that does make it to the Moon has passed through the Earth’s atmosphere and is therefore red in colour for the reasons noted above.
As the Moon gets higher in the sky you will begin to see the left-hand-side brighten and its colour become that of a normal full moon. This heralds the Moon moving out of the Earth’s shadow.
We’ve always referred to Mars as the Red Planet because of its surface color. But what’s below that dusty crust? The @NASAInSight mission is currently cruising through space, set to land on Mars and determined to find out. Watch: https://t.co/eKtxlfCJI1 pic.twitter.com/bxa3THCrFJ— NASA (@NASA) June 22, 2018
The best way to observe a total lunar eclipse is, in my experience, with the unaided eye and a warm drink, or at this time of year a late-night-barbecue.
Before observing it is usually a good idea to let your eyes adapt to the dark, but for lunar eclipses this isn’t necessary.
Instead make it an excuse to bring some friends around and ponder what might have been in your world cup pools if you hadn’t been given Panama.
Or come watch the eclipse from Blackrock Castle Observatory from 9pm and find interesting conversations galore.
Dr Niall Smith is head of research/head of Blackrock Castle Observatory at Cork Institute of Technology.
Further information about the sky is available on the CIT Blackrock Castle Observatory website at https://www.bco.ie/sky-matters/