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The Mercury Transit PFI Images

Image name: merc_pfi_transit.png (click image to enlarge)
Image size: 176.388 KB (512x768)
Date submitted: 11-Nov-1993

Notes on the graphic showing PFI images during the Mercury transit

1. The insets show the PFI data for the times and positions of the first
and second contacts (left) and third and fourth contacts (right).

2. The full-sun image is an SFD-compressed image taken at 11:16:23 UT
after the contact, AlMg filter. The exact times are:

zeroth contact you guess!
first contact 03:07:23 UT
second contact 03:13:48
central point 03:59:41
third contact 04:40:03
fourth contact 04:45:24
fifth contact you guess!

Here zeroth and fifth contact refer, of course, to when the X-ray coronal
occultation begins and ends.

3. The images of Mercury are cut and pasted onto a single representative
image. Only every fourth PFI was used, because otherwise they overlapped.

4. The first-contact data show that Mercury traversed a deep coronal
hole channel and its sharp eastern wall. A bright point flared up about
30 arc s N of Mercury, and its peak brightness is shown in the left inset.

5. The full-sun image has lots of interesting features, in particular al
large number of bright points. In addition one can see what looks like
a jet at about 4:00 pm position angle, nice overlapping loops in
the SE active region complex, and a huge coronal hole in the north.
Solar activity was extremely low at the time of the transit.

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