What do you see when you look up at the sky at night?

Unfortunately clouds a lot of the time, but if you time it right then you get to see a sky full of stars, galaxies and planets (and a Moon occasionally).

So the next question is why do you look up at the night sky?

Well the answer for me is very easy, because the sky is full of such amazing sights, how could you not look up at the night sky? When I look up at the night sky I don’t just see points of light I see thousands and thousands of thermonuclear factories, all churning out the stuff that we, and our planet, are made of. Sometimes they blow up as happened to one star in the Tarantula Nebula in 1987. The 1987 Supernova, aptly named SN1987A, was quite amazing because it was the first one visible by the naked eye from Earth since 1604. The 1604 supernova was from a star that blew up inside the Milky Way unlike SN1987A, which was 160,000 light years away in the Tarantula Nebula within the nearby large Large Magellanic Cloud (LMC). The other great thing about the 1987 Supernova was that it could be observed by telescopes and eventually the Hubble Space Telescope when is was launched 1990 (once it got fixed). I took the photo below of Tarantula Nebula a few years ago and have marked up where SN 1987 is:

What is really cool about SN1987A is that the co-discoverer was the New Zealander, Albert Jones, who sadly passed away in 2013. The other co-discoverers were staff at the Las Campanas Observatory in Chile. The HST could get a little closer than my setup and took this one in 1996:

The two rings are material that was basically excited by the explosion of the star. The central ring is the expanding shockwave which is compressing gas around what’s left of the star and causing it to heat up and emit. The other amazing thing that occurred back in 1987 was that this supernova offered an opportunity to compare how neutrinos behave in one of these events. It’s great to come up with a bunch of theories about how stars form and die but it’s even better when we get the chance to validate the theories through observations. On 23 Feb 1987 the new neutrino detector in Kamiokande, Japan, picked up 11 neutrinos. This was the first time that neutrinos had been associated with a supernova event and it was such a remarkable observation that it led to Dr Masatoshi Koshiba being awarded the Nobel Prize for Physics in 2002. Another interesting aspect of emitted neutrinos during a supernova is that they precede visible light observations because the neutrinos get out of the collapsing star before the visible light photons. The photo below is of the detector at Kamiokande that detected the 11 neutrinos from SN1987A (Kamioka Observatory website).

When I look up at the night sky these are the objects and discoveries I am thinking of. I am wondering which star will go supernova next, will it be Betelgeuse and wouldn’t it be amazing to witness that?