• Question: What was the best thing you have ever discovered about the stars or Sapce

    Asked by Fintan boyle to Mark on 4 Nov 2016. This question was also asked by 872xygg26.
    • Photo: Mark Kennedy

      Mark Kennedy answered on 4 Nov 2016:

      The best thing I have discovered happened this June. Some people I work with and I were looking at a binary star system (where 2 stars are orbiting each other) called FO Aquarii (there’s a picture of the system on the right of this page http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=fo+aqr&submit=SIMBAD+search and it’s called this because it’s in the constellation Aquarius https://en.wikipedia.org/wiki/Aquarius_(constellation)). Normally, this system is bright (we say that it had a magnitude of 13.7 to describe how bright it is). However, this time, the system was much fainter (it had a magnitude of 15.5!).

      Now, I know what you’re saying – 15.5 is bigger than 13.4, so why was the system fainter? Didn’t I mean it was brighter?

      Our way of describing something as bright in the night sky is weird, but all you have to remember is the smaller the number, the brighter the object! So a star that is magnitude 2 is much, MUCH brighter than a star that is magnitude 8!

      So, back to FO Aquraii. We found that it was fainter than usual. And this is important because people have been looking at this system since 1923, and it had never become fainter before! So we’re currently working on explaining why it’s so faint, and why it’s so important to study objects like this.