The backyard astronomer mapping Jupiter’s atmosphere
‘It’s been a little bit weird with me out in the middle of the night, you know, in the winter hours, and waking people up when I trudge in with snow on my boots,’ shares Steven Hill, an ‘amateur’ astronomer from Colorado, US. He has collaborated researchers from the University of Oxford, UK, to show that the make-up of Jupiter’s clouds does not match the conventional view.
Observations made from Hill’s backyard and later confirmed by working with an academic research team suggest that Jupiter’s clouds are situated too deeply within its warm atmosphere to be composed of ammonia ice. Instead, they are more likely to be ammonium hydrosulfide in a smoggy mixture.
Hill loved astronomy as a child and was fascinated with space in general, leading him to study for a degree in aerospace engineering before working in the ‘space business’ for a while. Growing a little tired of ‘building engineering systems for other people to do science,’ Hill was drawn to do some research of his own and enrolled in a doctorate of astrophysics, where he studied the earth’s upper atmosphere.
After his PhD, for several years Hill’s career largely focused on solar observation, as part of teams investigating space weather. He later moved into a managerial role leading a group of software developers.
When Hill felt that his day job as a software manager wasn’t fulfilling his ‘need for an outlet to do science or research’ he leant into astronomy as a hobby, and ‘maybe got a little bit carried away during the Covid era’.
Setup for success
Hill started out with what he describes as a ‘nice amateur telescope setup’ and became interested in the use of filters to look at the methane composition of the high atmosphere of Jupiter.
‘Amateurs have been doing that for years, if not decades,’ he says. After a little while, he became interested in observing weaker methane bands too, and started to spot other bands that he suspected might be ammonia.
‘I’ll generalise, but I’m really speaking about myself: as scientists, I think we tend to be neurotic and self-doubting,’ he says. ‘So, when I saw things that looked like they could be ammonia, I thought, uuhh, what’s wrong with my telescope? … I’m doing something funny here with the math, and I’ve gotten noise here, and it looks weird.’
When Hill repeated his observations enough times that they began to look self-consistent he realised he might really be onto something, and started to look for a way to confirm his results independently. He reached out to John Rogers at the British Astronomical Association who put him in touch with Patrick Irwin, a professor from the department of physics at the University of Oxford.
‘Initially, I was a little bit dubious,’ says Irwin. ‘But I started looking at his data and looking at the technique and I realised, oh, it does work. And actually, the ammonia maps that you’re getting out of it look awfully like the ammonia maps you get from the Juno microwave radiometer, and from the very large array radio telescopes, and they’re probing down deep.’
The ammonia maps generated using Hill’s equipment can be obtained far more quickly and at a tiny fraction of the cost of those accessed from more sophisticated equipment, opening further opportunities for amateur astronomers and citizen scientists to contribute to our understanding of Jupiter’s atmosphere.
Amateur or not?
Hill acknowledges that his doctoral degree and career pathway makes it tricky to figure out whether he is truly an amateur astronomer.
‘I don’t get paid for this, this is not what my career is, I was using amateur equipment on my own time, yet I have this background of training,’ he says. ‘There’s definitely a spectrum, and I think that folks who do have more training and are working in the citizen science domain can help bridge that gap between citizen scientists and professional scientists because they can share language.’
You need to find ways to support the amateur superstars
Hill believes we’re on the right trajectory to continue to make better connections between professional and citizen scientists, but that more could be done to address ‘unevenness’ in the extent to which citizen scientists are engaged in different disciplines. It is also important to find ways to better fund citizen science initiatives.
‘I think you need to find ways to support the amateur superstars … the people who really help coordinate and link citizen scientists to professional scientists,’ he says. ’In astronomy, there are people who write programs and applications that make what I’m doing possible.’
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