An Exo- Jupiter Unveiled

The Extreme Solar System conference at Santorini is off with a bang!

Number of announcements already in the first session, I'll catch up on the highlights later, and just give the, in my opinion, most interesting.

The California-Carnegie-AAT group has a genuine extrasolar Jupiter analog!

Jason Wright announced it in the first session.

It is one of several systems that have been monitored for ~ decade and been known to show a long term trend in velocity.
The velocity variation peaked a few years ago, but had not shown a full cycle, so the orbit was poorly constrained. The second turn just came recently and the orbital solution has collapsed to a quite robust fit, this one is real I think.

System is HD154345 - a G8V main sequence dwarf.
About 0.9 solar masses, slightly sub-solar metallicity ( [Fe/H] = -0.1), at a distance of 18 pc

The planet has projected (m sin(i)) mass of 1 Jupiter mass, in a 10 year orbital period, at about 4.4 AU from the star, with an eccentricity of only 0.07 +- little bit.

This is a Jupiter - a cold gaseous giant planet in the right place, which does not look to have migrated or done anything messy.
It is of course a fabulous target for low mass rocky planets interior to the current known giant, including in the habitable zone.
It is also a very promising indicator that the large number of known "trending" systems being monitored will resolve out to be solar system analogs - maybe 20-30% of stars being monitored may be solar system like if this all pans out - but that is speculative at this stage.

Really wonderful discovery and announcement. Paper is on its way soon I gather.

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"All truths are easy to understand once they are discovered; the point is to discover them." -Galileo Galilei
Yesterday, we started our goodbyes to Hubble's outgoing camera, WFPC2. It was literally 16 years ago that they first installed this workhorse onto the space telescope:
"A few centuries ago, the pioneer navigators learnt the size and shape of our Earth, and the layout of the continents. We are now just learning the dimensions and ingredients of our entire cosmos, and can at last make some sense of our cosmic habitat." -Martin Rees