Hello Bernd,


Guide gives for Mercury an elongation about 24 degrees and 24% illuminated,
at 0.71 AU from the Earth. As SOHO is at a distance of about 0.01 AU from
the Earth, the maximum parallactic effect is arcsin (0.01/0.71), that is 0.8
degree. So I don't believe that the parallactic effect coud explain the
position of Mercury so close to the sun.

Perhaps a nearby asteroid ?

I looked at the animation (EIT 195). That disk suddenly appears on
2005/07/17 between 22:00 and 23:12, visible on 1 frame, then disappears and
appears again between 22:36 and 23:12, and remains visible for the rest of
the animation. It has no perceptible motion.

So I suppose it is no more than an artefact.


Laurent

----- Original Message -----
From: "Bernd Brinkmann" <bernd.brinkmann@...>
To: <guide-user@yahoogroups.com>
Sent: Monday, July 18, 2005 10:09 AM
Subject: [guide-user] SOHO as home planet?


> Hello Bill,
>
> I ask this because in actual EIT 171, EIT 195, EIT 284 and EIT 304-
> images (2005/07/18 05:00 UT) there is a small disk visible at the right
> side of the sun. Is the parallax this large that it could be Mercury? This
> is my only explenation.
>
> So if I could set SOHO as homeplanet in Guide I could proof this.
>
> Clear skies
> Bernd
>
> Bernd Brinkmann
>
> Sternwarte Herne, MPC code A18
> Herne, Germany