To continue where we left off on Friday, for stargazers who'd like to glimpse Rosetta from ground as she closes in...

No. 1 factor? Visibility conditions, obviously, which will depend on the location of the observer. During approach Rosetta will be in the sky's Southern hemisphere. If we consider observers in Europe, it helps to be in the South (which is why Kristin gets to go to Tenerife!).

For observers on the Canary Islands:

12/13 November:
18:30 UTC: Rosetta rises, range is 460 000 km.
23:30 UTC: Max. elevation of 42º reached, range is 280 000 km.
04:20 UTC: Rosetta sets, range is 120 000 km.

For observers in Berlin:

12/13 November:
17:40 UTC = 18:40 CET: Rosetta rises.
21:30 UTC = 22:30 CET: Maximum elevation of 18º reached.
01:30 UTC = 02:30 CET: Rosetta sets.

Berlin is considerably worse than Tenerife, especially the low elevation. For an observer in Central Europe, Rosetta will be visible in the first part of the night, low in the South.

Rosetta’s movement on the sky will be slow before 13 November 05:00 UTC, so the visibility times and elevations are similar for the night before. But for the night of 11/12 November, the range is roughly 1 million km, i.e. considerably larger than during the following night.

The weak magnitude (17 - 12 mag expected) and low elevation imply that at least a medium size telescope is needed (sorry guys!). Kristin suggests an 80 mm aperture, but 300 mm or more would be preferable.

You can obtain coordinates for your own location via the Horizons website.

 --Amruta