Archive for July 22, 2014

07/22/2014 – Ephemeris – Rosetta spies a cosmic rubber ducky

July 22, 2014 Comments off

Ephemeris for Tuesday, July 22nd.  Today the sun will be up for 15 hours even, setting at 9:18.   The moon, half way from last quarter to new, will rise at 3:38 tomorrow morning.  Tomorrow the sun will rise at 6:19.

The European Space Agency (ESA) Rosetta spacecraft is closing in on Comet 67P/Churyumov-Gerasimenko, also known as Comet Cherry-Gerry, or Comet C-G.  After photos of the comet’s nucleus were published last week it has acquired a new nickname: Rubber Ducky.  The nucleus may be a contact binary with two comet nuclei that stuck together after a slow speed collision.  Further study may reveal the nature of the two pieces.  Rosetta has more than a year to study the comet.  It has a lander craft called Philae that can land on one of the pieces of the nucleus.  No one expected the possibility of two possibly dissimilar comet nuclei to study.  Rosetta will enter orbit of the comet August 6th.

Times are for the Traverse City/Interlochen area of Michigan.  They may be different for your location.


July 4, images

A hint of strangeness appears on July 4, 2014. What’s that lump on the side in that third image? Credits: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA

July 14th animation

An animation of Comet C-G rotation on July 14, 2014. The 30 pixel wide image has been smoothed. The actual rotation rate is 1 rotation every 12.4 hours. Credits: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA

For more information go to, or search: esa rosetta.

The post that explains this image more fully is here.

ESA has a policy of weekly releases, so expect a new one this Wednesday, Thursday or Friday.