Archive for planet formation

R.I.P. Willy Kley (1958-2021)

Posted in Biographical, The Universe and Stuff with tags , , , on December 29, 2021 by telescoper

Once again it is my sad task to pass on news of the death of a colleague from the field of astrophysics. Prof. Dr. Wilhelm (“Willy”) Kley of the Institut für Astronomie & Astrophysik at the Universität Tübingen
in Germany passed away suddenly on 21st December 2021, at the age of 63.

Here is the official announcement (in German) from his institution:

Willy Kley was a computational astrophysicist who worked on accretion processes, especially in the context of the formation of planets and planetary systems. I knew him a little personally, as he was for a time in the Astronomy Unit at Queen Mary & Westfield College (as it was then called) at the same time I was there. He worked with the group led by John Papaloizou, alongside Richard Nelson and others, and I was working on cosmology, so we didn’t work together, but I did get to know him a bit and had a number of interesting discussions. He was a very nice man as well as a first-rate scientist. Looking at his (extensive) publication list it seems that he continued to collaborate with former QMW colleagues after his return to Germany in 2000.

His death was unexpected – I believe he suffered a heart attack – and I’m sure the news will come as a shock to many of his friends and collaborators. To them, and to his family, I send heartfelt condolences.

Baby Planet Pictures…

Posted in Astrohype, The Universe and Stuff with tags , , on October 20, 2011 by telescoper

My eye was caught this morning by this dramatic picture on the front page of the Guardian website, linked to a story about the discovery of a very young planet:

I wonder how many people looking at it thought that it was an actual picture of a planet actually forming? In fact the above graphic is just an “artist’s conception” of the view near the planet, which is called LkCa 15b. The real picture is considerably less dramatic:

What you see is (left) a disk of dust and gas surrounding a star cleverly made visible by masking out the light from the star, which is much brighter than the disk.  On the right you can see a blow up of the inner region of the system, which appears to show a Jupiter-like planet associated with an irregular blob of material, out of which it probably condensed and from which it may still be accreting.

The size of the picture on the right is worth noting. The angle indicated is 76 milli-arcseconds. This is the angle subtended by  the  width of a  human hair at distance of about 130 metres…