Early this morning the old crescent Moon, Jupiter, and Venus formed a striking celestial dogleg. As the morning progressed, the Moon closed the gap with Jupiter on the way to crossing paths with the King of Planets.

Two fellow ASH members and I were fortunate enough to witness the occultation of Jupiter from the ASH Naylor Observatory. To do so we had to dodge the fair weather clouds that littered the sky and nearly occluded the occultation.

Instruments used were a 5" f/5 achromatic refractor, an 8" f/6 Hardin Dob, a 12.5" f/6.5 Cave Newtonian, and a 17" f/15 classical Cassegrain.

I saw the Moon grow close to the planet through the 17" and 5" and watched the actual event through the 12.5" and the 8", using primarily a 26mm Tele Vue Ploessl (79x) and a 20mm Meade Wide Angle (66x) respectively. Seeing Jupiter being consumed gradually by the lunar surface beginning at 11:05 a.m. EST (16:05 UT) was a blast. The Galilean satellites were not visible, of course.

While we waited for Jupiter to reappear, we observed the Sun through an 8" Celestron Orange Tube SCT, a 2" generic 32mm Erfle, and a full aperture Orion glass solar filter. The large active region AR 10696 was quite impressive and was large enough to be seen without optical aid but otherwise the sun seemed to be devoid of sunspots.

The clouds were not so kind for the reemergence of Jupiter at 12:09 p.m. EST (17:09 UT) but I did catch it about 6 minutes later through the 5" achromat and a 16mm Brandon.

When it comes to daytime planetary occultations I suppose seeing half of one isn't too bad.

Before I left the observatory I viewed the Moon, which was by then far to the southwest, and Venus through the 5" and the 17" and a 55mm University Optics Ploessl (118x) but I couldn't locate Jupiter.

Dave Mitsky

__________________
Chance favors the prepared mind.
De gustibus non est disputandum.
Never attribute to malice that which can be adequately explained by stupidity.

Fellow Astronomers...

I would like to share with you all my experience of the Occultation in Chicago:

I had planned my time at the Adler Planetarium for this event, and at first upon my arrival, wasn't too sure if I should go ahead with the session. The skies by the lakefront were hazy, and I had a damned time trying to locate the crescent moon. Parked by the Adler, I scanned the skies searching and searching, both with my naked eyes and with binoculars.

Then in an instant, the moon popped into view, quite clear. I then committed myself to observe the Occultation event. With 10 minutes to spare. I rushed into the Adler, signed in and rushed into the telescope storage area. With moments to spare, I didn't want to use a dob, didn't want a refractor...so I grabbed me a 8" s/c, a solar filter and the eyepiece case, and carried it all to my spot.

I set up on the Adler's observation terrace and again searched for the moon, which became elusive once again. Spotting it with one minute to spare, I focused in on it with a 20mm wide angle eyepiece...and there it was...Jupiter just outside of the lit side of the crescent Moon! I thought I was too late as I hesitated setting up. But my decision was greatly rewarded.

It was brighter than I expected, and although the contrast was quite low, the field awash in blue, I could still discern banding on the planet. I watched in amazement as the bright disk slowly got engulfed...bit by bit...and then all of a sudden...it was gone!

I paused for a bit to digest what I just saw. I never observed a daytime Occultation before and thought it quite cool that it actually happened when it did. With Chicago Astronomer Curt's great graphic of the event, I knew exactly where it would hit.

While waiting for the emergence, I put on the solar filter on the aperture of the scope and did me some solar disk watching. A very large group of sunspots were predominate on the surface with two much smaller groupings on each limb. I observed very good outer sunspot shading and some granulation of the surface, as I cycled thru various eyepieces ranging from 25mm down to a 3.6mm. It was a bit windy and chilly where I was set up, and the winds trembled the scope. I returned to a 20mm and left it there for the remainder of the session. I also chatted with Adler visitors, shared views and talked astronomy.

I was so engrossed in a conversation with a visitor than I missed the point of emergence, but caught it as it was entirely leaving the dark side of the Moon. Still a bright disk and showing banding. Some could not see the disk nor the crescent, but I guess they expected high contrasted images in the eyepiece.

I remained for some time after wards showing the public sunspots and chatting about the recent auroras.

It was indeed another moment not to be forgotten for me, as yet another astronomical phenomenon noticed and enjoyed by the Chicago Astronomer.

__________________
Joseph Guzmán
Administrator
The Chicago Astronomer
www.chicagoastronomer.com
http://astronomer.proboards23.com

Telescope/Observatory Operator
Adler Planetarium & Museum

"We are all in the gutter,
But some of us are looking at the stars..."
Oscar Wilde - 1854-1900