Because Science was inconsiderate enough to have an announcement about a major astronomy finding while I'm on leave, let's pretend to do some outreach (aka wittering on Twitter). #phosphine on #Venus is a pretty damn cool result. I'm still peeved I couldn't do this on work time

I'm lucky in that I know a couple of people on the Nature Astronomy paper: https://www.nature.com/articles/s41550-020-1174-4
@davecl42 and @pbrandonrimmer One I know from sf conventions, and one because he works in the same building as me (well, back when we worked in buildings...).

This just goes to show the importance of serendipity. I wouldn't know @davecl42 without sf conventions, & I've learnt a lot from him. He was also instrumental in getting the people studying phosphine and the people looking for phospine together. Knowing people is a superpower.

Brief aside: that's one thing that's going to be a real problem for the PhD students and first job post-docs right now - it's way harder to connect to people at the moment. Twitter is a great way to do this - I'm using it to connect to Black and indigenous scientists right now.

Back to fun with #PhosphineOnVenus
Why phosphine? It can be a biomarker, and unlike some sulfur compounds which may also be useful biomarkers, it's pretty easy to distinguish phosphine from all the weird sulfur compounds that might result from Venus' weird sulfur chemistry.

As others have said, obviously it's no guarantee that there's life on Venus. (And if there is, our new alien overlords are Very Small.) But either it's new chemistry or it's new biology. Either way, this is pretty cool.
(Known chemistry just can't make enough phosphine.)

I'm going to talk a bit about the mechanisms behind the scenes. This work was done with two telescopes - the JCMT in Hawai'i and ALMA in Chile, looking at sub-mm wavelengths. The initial detection was done with JCMT, and it was followed up with ALMA.

Without the JCMT detection, they wouldn't have got the ALMA time - it was a reasonable amount of time, and the detection meant they got Director's Time. (Director's Time is time reserved for the telescope Director to assign as they will, usually to do some cool science

that's come up outside of the usual cycles for putting in proposals for observations. Many telescopes have this discretionary time for Cool Stuff like this.)
With ALMA in particular, they did a bunch of work to check it's really phosphine. Like checking a similar spectral line...

(for Deuterated water) already known to be found on Venus, to check they were sensitive to the right sort of things.
ALMA also had some weirdnesses in the data analysis. Like, they had big spectral "ripples". This is most likely a weird artefact because:

Venus is very bright.
Venus almost fills the primary beam of the telescope. (You can kind of think of the primary beam as the area the telescope's optimised to see best in - you can then point your primary beam across the sky by steering the telescope - sort of.)

*watches real astronomers faint at my approximation of the primary beam*
Bright things that fill your primary beam are a bit of a difficult thing to deal with - smaller bright things are possible to subtract. And you don't want to subtract the bright thing you're looking at.

This is going to be a problem for e.g. @SKA_telescope too, especially if we do any solar observations.
So they had to take away some of the shortest baselines between antenna pairs in ALMA, so that the ripple was reduced. Still got brilliant science out of it.

This meant they departed from the standard ALMA data reduction pipelines. Another thing for the SKA to note - we're planning on even more automation than ALMA, so it's good to know the kinds of observations that may need different strategies.

Telescopes like the SKA may be able to look for similar biomarkers (not the phosphine one - it's at the wrong wavelength, unless it's from a very long way away, and it's redshifted into our wavelengths, but then it'd probably be too faint to detect); it'll be very sensitive.

ALMA may also be able to look at some nearby exoplanets, but that would require a lot of telescope time. But there will be much more willingness to put in that time, now we've got an excellent detection from Venus. We may do more Venus observations to get a better understanding.

There was a question about a Russian probe mission to Venus. Unless the probe was already going to look for phosphine or bacteria, it's very unlikely to be changed to look for them unless it's still in the design stages. Space missions take years to plan and build.

Once you've planned it, it's hard to change, because you've got strict limits on size, weight, power: launching stuff into space means you get one shot. It has to be right. Otherwise it's a very expensive failure. If the mission was already looking for this stuff or very closely

related stuff, it may still be possible to change, but if it's very close to launch, we'll just have to settle for Different Cool Stuff.
Anyway, it's a brilliant result, and whatever has been found, it's New Science!
Congrats to all who worked on it!