Venus Transit: Halo Seen

Heh! Nice transit! I saw a diffuse halo around Venus on the sun side. The
colour was a bit lighter than the sun's surface. It looked like the picture
on page 76 of the June Sky and Telescope magazine.

I noticed the halo around third contact as Venus was exiting the sun's
surface. Did anyone else see this halo? I did not notice the halo when Venus
was far from the edge, it may have been there, I did not focus attention
closely enough to see if there was. What causes this halo, Venus
atmosphere, or earth's blurring atmosphere? It was a hazy kind of day.

A side point: My partner said he saw a brief light ring form when Venus was
half off the sun. He said it went around Venus from the 9 o'clock position
to the 12 o'clock position, then cut down to a smaller segment, then
disappeared. I did not see that. It must have happened fast.

We both saw the black drop effect, it started as a small fan shape, then
grew into a larger fan shape. There was no thin filament that we could see
at the start of the black drop effect activity.

Brien Stratton

Toronto, Canada

The halo was quite obvious on the exit and most pronounce at the half off
point. I could still make it out when Venus was almost totally off the sun.
I lost it when venues was completely off.


"Brien Stratton" wrote in message
news
Heh! Nice transit! I saw a diffuse halo around Venus on the sun side. The
colour was a bit lighter than the sun's surface. It looked like the
picture
on page 76 of the June Sky and Telescope magazine.

I noticed the halo around third contact as Venus was exiting the sun's
surface. Did anyone else see this halo? I did not notice the halo when
Venus
was far from the edge, it may have been there, I did not focus attention
closely enough to see if there was. What causes this halo, Venus
atmosphere, or earth's blurring atmosphere? It was a hazy kind of day.

A side point: My partner said he saw a brief light ring form when Venus
was
half off the sun. He said it went around Venus from the 9 o'clock
position
to the 12 o'clock position, then cut down to a smaller segment, then
disappeared. I did not see that. It must have happened fast.

We both saw the black drop effect, it started as a small fan shape, then
grew into a larger fan shape. There was no thin filament that we could see
at the start of the black drop effect activity.

Brien Stratton

Toronto, Canada

Interesting obervation Enyo. I stopped seeing the halo when it was about 1/4
left to go off. When Venus was last exiting, it started to look flatter,
like a pancake that was being pulled across the sun.

My partner gave me some more detailed info on the light arc if anyone is
interested:

The arc stated just after Venus was leaving the sun's edge, after the black
drop effects were done. He said that the arc of light went from the 8
o'clock position to the 2 o'clock position, but that there was a brighter
segment to the arc from about 10 o'clock to the 2 o'clock position. This may
have been a "polar spot". Then the arc disappeared completely. My partner is
a novice, so was not aware of these phenomenon mentioned in the S and T
magazine. I told him after that this may have been what he saw. Maybe we
have a new astronomer joining the fold. He took some photos through the
eyepiece, so hopefully he got some good shots, but the camera was not
attached to the eyepiece, and he is a complete newbie. I have my doubts they
will turn out that good.

Brien Stratton




"Enyo" wrote in message
...
The halo was quite obvious on the exit and most pronounce at the half off
point. I could still make it out when Venus was almost totally off the
sun.
I lost it when venues was completely off.


"Brien Stratton" wrote in message
news
Heh! Nice transit! I saw a diffuse halo around Venus on the sun side.
The
colour was a bit lighter than the sun's surface. It looked like the
picture
on page 76 of the June Sky and Telescope magazine.

I noticed the halo around third contact as Venus was exiting the sun's
surface. Did anyone else see this halo? I did not notice the halo when
Venus
was far from the edge, it may have been there, I did not focus attention
closely enough to see if there was. What causes this halo, Venus
atmosphere, or earth's blurring atmosphere? It was a hazy kind of day.

A side point: My partner said he saw a brief light ring form when Venus
was
half off the sun. He said it went around Venus from the 9 o'clock
position
to the 12 o'clock position, then cut down to a smaller segment, then
disappeared. I did not see that. It must have happened fast.

We both saw the black drop effect, it started as a small fan shape, then
grew into a larger fan shape. There was no thin filament that we could
see
at the start of the black drop effect activity.

Brien Stratton

Toronto, Canada

On Tue, 8 Jun 2004 11:05:11 -0400, Brien Stratton wrote:
interested:

The arc stated just after Venus was leaving the sun's edge, after the black
drop effects were done. He said that the arc of light went from the 8
o'clock position to the 2 o'clock position, but that there was a brighter

I can confirm this observation, both my wife and I saw it at the time,
but more fom six to nine o'clock without an upper half.

Cheers,

uwe

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Herford, Germany \\\\\\\\\\\\\\\\\\\\\\\\\\ (52.0N/8.5E)
GPG Fingerprint: 2E 13 20 22 9A 3F 63 7F 67 6F E9 B1 A8 36 A4 61

Hi,

None of you state in which instrument (diameter) you seen this "light arc"
that not all users seen (but many used small refractors and low power).
I suspect that you used a short focal eyepiece (ot a high power
barlow/powermate) and a large scope, say at least 180 mm in dia.
Do you confirm ?
Here is a simulation of this arc of light due to the scattering of the
sunlight in the clouds of Venus :
http://www.astrosurf.com/lombry/Docu...rc-lumiere.jpg
It can also be seen on the other side if Venus is more away from the sun.

Thierry
http://www.astrosurf.com/lombry/


"Brien Stratton" wrote in message
news
Heh! Nice transit! I saw a diffuse halo around Venus on the sun side. The
colour was a bit lighter than the sun's surface. It looked like the
picture
on page 76 of the June Sky and Telescope magazine.

I noticed the halo around third contact as Venus was exiting the sun's
surface. Did anyone else see this halo? I did not notice the halo when
Venus
was far from the edge, it may have been there, I did not focus attention
closely enough to see if there was. What causes this halo, Venus
atmosphere, or earth's blurring atmosphere? It was a hazy kind of day.

A side point: My partner said he saw a brief light ring form when Venus
was
half off the sun. He said it went around Venus from the 9 o'clock
position
to the 12 o'clock position, then cut down to a smaller segment, then
disappeared. I did not see that. It must have happened fast.

We both saw the black drop effect, it started as a small fan shape, then
grew into a larger fan shape. There was no thin filament that we could see
at the start of the black drop effect activity.

Brien Stratton

Toronto, Canada

I did not see the light arc (Sal, my observing partner did), but I did
notice myself at third contact a halo around Venus, which was a slightly
lighter colour about 1/5 or 1/6th the width of the planet. It was a subtle
effect, yet was there. The halo was much thicker than the thin "light arcs"
attributed to the Venusian atmosphere. I don't know what causes the halo,
whether it is the same phenomenon or not as the light arc.

My scope is an 8" f/9 dedicated newtonian solar scope with precision
uncoated optics. I was using a 20mm, and a 25mm Televue plossls, no
barlows.

Brien Stratton




"Thierry" Answer direct via http://www.astrosurf.com/lombry/post.htm wrote
in message ...
Hi,

None of you state in which instrument (diameter) you seen this "light arc"
that not all users seen (but many used small refractors and low power).
I suspect that you used a short focal eyepiece (ot a high power
barlow/powermate) and a large scope, say at least 180 mm in dia.
Do you confirm ?
Here is a simulation of this arc of light due to the scattering of the
sunlight in the clouds of Venus :
http://www.astrosurf.com/lombry/Docu...rc-lumiere.jpg
It can also be seen on the other side if Venus is more away from the sun.

Thierry
http://www.astrosurf.com/lombry/


"Brien Stratton" wrote in message
news
Heh! Nice transit! I saw a diffuse halo around Venus on the sun side.
The
colour was a bit lighter than the sun's surface. It looked like the
picture
on page 76 of the June Sky and Telescope magazine.

I noticed the halo around third contact as Venus was exiting the sun's
surface. Did anyone else see this halo? I did not notice the halo when
Venus
was far from the edge, it may have been there, I did not focus attention
closely enough to see if there was. What causes this halo, Venus
atmosphere, or earth's blurring atmosphere? It was a hazy kind of day.

A side point: My partner said he saw a brief light ring form when Venus
was
half off the sun. He said it went around Venus from the 9 o'clock
position
to the 12 o'clock position, then cut down to a smaller segment, then
disappeared. I did not see that. It must have happened fast.

We both saw the black drop effect, it started as a small fan shape, then
grew into a larger fan shape. There was no thin filament that we could
see
at the start of the black drop effect activity.

Brien Stratton

Toronto, Canada

I did not quantify the length of the light arc but at maximum extent (at
half off) it was close to the entire half disk off the sun. I was using an
AP130 + Barcon + Herschel wedge + Binoviewer and 18mm Radians. Seeing was
lousy with the edge really undulating. The web site
(http://www.perseus.gr/Astro-Planet-Ven.htm) does not work for me with
Mozilla, FireFox or IE browsers.



"Thierry" Answer direct via http://www.astrosurf.com/lombry/post.htm wrote
in message ...
Hi,

None of you state in which instrument (diameter) you seen this "light arc"
that not all users seen (but many used small refractors and low power).
I suspect that you used a short focal eyepiece (ot a high power
barlow/powermate) and a large scope, say at least 180 mm in dia.
Do you confirm ?
Here is a simulation of this arc of light due to the scattering of the
sunlight in the clouds of Venus :
http://www.perseus.gr/Astro-Planet-Ven.htm
It can also be seen on the other side if Venus is more away from the sun.

Thierry
http://www.astrosurf.com/lombry/

In article ,
Thierry Answer direct via http://www.astrosurf.com/lombry/post.htm wrote:

None of you state in which instrument (diameter) you seen this "light arc"
that not all users seen (but many used small refractors and low power).
I suspect that you used a short focal eyepiece (ot a high power
barlow/powermate) and a large scope, say at least 180 mm in dia.
Do you confirm ?
Here is a simulation of this arc of light due to the scattering of the
sunlight in the clouds of Venus :
http://www.astrosurf.com/lombry/Docu...rc-lumiere.jpg
It can also be seen on the other side if Venus is more away from the sun.

Thierry
http://www.astrosurf.com/lombry/

One observer claimed to have seen the "light arc" in 20x80
boniculars, but I think that's overly optimistic. If this light arc
would have been visible already in binoculars, it should have meen
much more clearly visible in these images:

http://vt-2004.kva.astro.su.se/

Btw I used these images to try to estimate the stellar magnitude of Venus
when very near but outside the Sun's limb. I got a magnitude of
approximately -10 to -12 i.e. somewhere between the brightness of the
half moon and the full moon. And that's some 200 times brighter than
when Venus usually is said to have acheived "greatest brilliancy" when
it reaches magnitude -4.5 to -4.7


-----------------------------------------------------------------------

Btw regarding an earlier discussion here about why astronomers
usually get so old (at least prominent astronomers from past times):
Jeremiah Horrocls, who was the second person to predict a Venus
transit and the first person to observe such a transit, died at the
age of only 22 years, two years after having observed the 1639 Venus
transit.

http://es.rice.edu/ES/humsoc/Galileo.../horrocks.html

--
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Paul Schlyter, Grev Turegatan 40, SE-114 38 Stockholm, SWEDEN
e-mail: pausch at stockholm dot bostream dot se
WWW: http://www.stjarnhimlen.se/
http://home.tiscali.se/pausch/

Here is an image of the halo taken by Stephan Seip in Germany with an AP 155
EDF refractor and Baader Hershel Wedge:

http://www.photomeeting.de/astromeeting/sun/040608a.htm

RC

(Paul Schlyter) wrote:

http://vt-2004.kva.astro.su.se/

Btw I used these images to try to estimate the stellar magnitude of Venus
when very near but outside the Sun's limb. I got a magnitude of
approximately -10 to -12 i.e. somewhere between the brightness of the
half moon and the full moon. And that's some 200 times brighter than
when Venus usually is said to have acheived "greatest brilliancy" when
it reaches magnitude -4.5 to -4.7


Paul,

That is an interesting result. Why do you think Venus brightens so
much when it is in line with the sun? The SOHO images showed the
planet fading significantly as it approached the sun's limb. If it
really does brighten near transit as you say, a plot of brightness
versus distance from the sun would be worth many thousands of words!

Tom