Date: Tue, 7 Nov 2000 15:15:18 -0700 (MST)
From: xxxxxxxxx (Cliff Toner)
Subject: MDI Roll angle 

Jesper,

I just completed another estimate of MDI's roll angle "error".

In May '00 we recorded two full-day drift scans (at TD & ML) and noon drifts
at all of the other sites.  I used these to cross-correlate between GONG
and MDI.

The results:   0.19 +/- 0.04 degrees

and the results from the Mercury transit last November: 0.22 +/- 0.03 deg.

i.e., the same, within errors.

Here's a crude picture:              "N"
                                       ~0.2 deg.
                                      |   / N_solar
                                      |  /
                                      | /
                                 E----|----W
                                      |
                                      |
                                      |
                                     "S"

i.e., ~0.2 degrees clockwise from the vertical.

How do you think this will affect the meridional flows?

Cliff