LtE in CMO #278

From Nicolas BIVER

® . . . . . . . .. .Date: Mon, 25 Aug 2003 16:26:20 +0200 (CEST)

Subject: Mars drawings 23rd and 24th August 2003

Dear All,

Since August 20, I switched to my new 41cm F/4.3 newtonian (J. M. Lecleire optics - homemade dobsonian-like otherwise). Unfortunately, as pointed out by Christophe, the seeing has not been good lately (likely due to northern cooler winds...) in France. Maybe I should have used the 25.6cm telescope several of the last nights...

The August 23rd is the best recent observation so far... On the other hand, with these nice new optics, I can nearly see Phobos and/or Deimos every night (depending on their elongations), without difficulty (sometimes even with Mars still in the field of view. The large magnification 700×, is better for this purpose.

On Aug. 23 observation, Phobos was at 20" to the left above Mars limb, the other lower resolution drawing shows both of them the following night.

Drawings information:

mars2003-08-23-NB.jpg:

Date: 2003 Aug. 23, 00:17:00 UT

CM = 018W Ls= 246° 　Dia.=25.0"

Seeing: 6-7/10 (fair)

Transparency 9/10

Telescope: 407mm F/D 4.3 ×700

Versailles, FRANCE

mars2003-08-24-NB.jpg (with Phobos and Deimos)

Date: 2003 Aug. 24, 00:17:00 UT

CM= 009°W Ls= 247°　 Dia.=25.1"

Seeing: 4-5/10 (poor)

Transparency 9-7/10

Telescope: 407mm F/D 4.3 ×700

Ablis, France

Clear and Steady Skies,

® . . . .Date: Fri, 29 Aug 2003 20:39:49 +0200 (CEST)

Subject: Re: 20030828 Mars opposition ... Drawings

Dear all,

Before bad weather came I got a last look at Mars with somewhat better seeing, but first maybe because I switched back to the 25.6-cm Newtonian... less sensitive. At the end of first drawing I rushed back home with the 10" in the hands to get the 16" out... but images got a bit worse and clouds were coming in. (Aug. 24-27 drawings on my webpage)

Here are the 2 drawings of the Perigee/Opposition night:

(left): 2003-08-27 22:10 UT

CML=302°W 　Dia.=25.1" Ls=249°

Seeing 6/10 (fair-good) Transparency 7-8/10

25.6-cm Newtonian　×507

Versailles (France)

(right): 2003-08-28 00:10 UT

CML=332°W　 Dia.=25.1" 　Ls=249°

Seeing 3-5/10 (fair-poor) Transparency 0-8/10 (between clouds)

40.7-cm Newtonian ×700

Versailles (France)

Clear and Steady skies,