Seiichi Yoshida from Kanagawa, Japan, offers this visualization of the amazing developments of 17p/Holmes with its sudden and dramatic increase in magnitude - quite unlike any other comet! And especially odd when considering this comet was well on a course away from the sun rather than nearing the sun. The graph also shows that the comet is still rather bright.
I observed the comet at 250, November 28, UTC.
Skies were clear, but light polluted. The nearly full moon was rising.
The comet is no longer a naked eye object. I could not find it in the binoculars. It was not visible in the view finder. I've talked with an observer in Belgium and one in Germany and they say in their dark sites the comet is still visible with the naked eye.
Through the 3 1/2 Questar, the comet is very large, but very, very faint.
I lugged out the 10 inch reflector because it gathers more light than the Questar. It was easier to find.
Had I not known there was a comet in that area of the sky, I would easily overlook it.
The comet is elongated. There is no nucleus. Averted vision is needed for the comet.
I took the photograph over a 5 minute exposure.
Comet Holmes has been so different from any other comet I've ever observed. It was a nothing little comet that would swing around every 6 point something years and go largely unnoticed. On the way out from the sun, it brightened!
It has stayed bright and remains a naked-eye object.
Each night brings a wonderful moment of "wonder what it will look like tonight?"
Compare this image taken on October 31st ...
With this image taken on November 15th.
It was my first visit. Bradley is the observatory on the campus of Agnes Scott College in Decatur, GA -- one of the fomerly separate towns now enveloped by Atlanta. The telescope is a 30 inch Cassegrain.
The night began with a lecture by the Chris De Pree, Director, Bradley Observatory Associate Professor of Physics & Astronomy -- "Sixty Years of Amateur Astronomy". I expected a 75 year old man sharing his own experiences, but instead De Pree is much younger than 60. The "60 years" in the lecture was the life span of the Atlanta Astronomy Club. He did a great job, and made a lot of interesting points.
He ended his lecture with a definition of amateur astronomy, pointing out that "amateur" comes from the Latin word, "amator" - meaning lover.
"Lover of stars."
I like that.
Well, it is interesting, but not amazing.
We went into the small planetarium and Amy Lovell, Assistant Professor of Physics & Astronomy, conducted a program for us. She did an awesome job, and she had a great group of young people asking lots of questions.
As good as Amy did in the planetarium, that was not the amazing thing I saw tonight.
When the planetarium program was over, we climbed the dark stairway to the observatory. It was completely cloudy when I arrived Agnes Scott, but now it was a very clear sky.
We looked first at Alberio, a double star that has a dramatic difference in color. You can see this difference in this photo from my files, which I snapped in August 2004:
As interesting as this double star is, it is not what I found to be so amazing tonight.
We then looked at Comet Holmes. For this we did not look through the main telescope, but through the smaller 6 inch refractor mounted on the side of the larger 30 inch telescope. After observing this for several nights, I was stunned at how dim the comet was. I could barely see the nucleus, and only with great effort with averted vision. The smaller, inner coma, and the larger halo that I've seen previous were not present - it was just one squashed halo.
When I got home, I looked through my Questar so I could compare "apples to apples" in terms of using the same telescope I've used for the past several nights. The view was the same. Comet Holmes is disappearing.
The remote observatory in the Canary Islands was shut down for clouds by the time I got home, but earlier this evening it was up and running. Olaf from Belgium shot these images using both the higher powered 14 inch SCT and the wide field of the Televue 85 APO refractor:
But the fading of the comet is not amazing - it is expected.
The most amazing thing I saw tonight came while I waited in line in the observatory.
The dome was open and you could see the light-polluted skies of Atlanta through the slot. There were red lights throughout the small, circular room. In the center of this room is an old telescope that once belonged to an amatuer astronomer (lover of stars), which was then sold to Agnes Scott.
The first person to look through the telescope was a child. He climbed this ladder, which from his perspective must have been hugh. Each step was an effort for his tiny legs. When he looked through the telescope he was silent.
"Can you see anything," someone asked.
The child said nothing.
"Can you see the stars," someone asked.
The child said nothing.
An adult climbed next to the child and said, "Let me see if I need to reset the telescope so you can see it."
"That's OK," he said, without moving his eye from the eyepiece.
"What do you see?"
"I see a blue star and a white star," the child said, still not stirring from the telescope.
I had the feeling that what the child really wanted to say was, "Leave me alone. It's taken 385 years for this light to arrive to Earth, and I need to savor this moment."
That was what I found amazing.
Or perhaps the word is "moving."
I was witnessing a child becoming an amateur astronomer - amator - lover of astronomy.
The second image used the 14 inch SCT, with a power of about 450. The image captures what the eye cannot see at that power. Notice the hint of trails coming from the nucleus? I've been able to see just a hint of one such trail, with averted vision, and with well dark-adapted eyes.
UTC: 2007 November 2 0200 UTC.
10 inch reflector. 2" E-lux eyepiece: Most prominent feature tonight is a star in the background that Holmes occulted earlier tonight. It is still in the outer halo.
The comet is still large and bright. Still appears to have a star on the edge of the inner coma. The inner coma is uniform. No mottling. Averted vision adds nothing. Surrounding halo continues to have a distinct edge on the NE side. On the opposite side, the SW side, it fades away - but I don't believe it fades as much as it did last night.
With 32 mm eyepiece, everything looks sharper. I can see the stellar nucleus and the bright star it is passing through, which was visible with the 2". Now I can see a third star on the SW side. I can see that third star only with averted vision.
There is some mottling on the halo.
With averted vision, the inner coma takes on a hint of a oval shape rather than round.
32mm with 2x barlow: Fills about 1/4 of FOV. More stars become visible. Next to bright star in the halo, there is a second star, not nearly as bright. It is at this point that star is on the SE side. Distinct edge is still distinct. Again, averted vision reveals a hint of oval shape rather than round shape in the inner coma.
Definite mottling on outer halo. There seems to be rays or streaks radiating from the stellar nuclus.
12.5 mm with 2x: certainly takes the entire FOV. The inner halo is definitely oval.
Transparency excellent, seeing fair.
Third magnitude stars easily seen.
Comet clearly seen with naked eye. Does appear slightly fuzzy.
Through 10 inch telescope, with 2" E-lux eyepiece. There is a single star-like object on the NE edge of the central, bright coma. Central coma evenly distributed. The halo - on the NE side, the edges of the outer halo are well defined and sharp. On the SW side, the edges of the outer halo fade away. The halo is slightly smaller on the SW side. Outer halo has no gaps, etc - it is evenly distributed.
With 32 mm eyepiece, no barlow. The fading on SW side is more pronounced, the NE side - the sharp side is still sharp, and more so with averted vision.
With 32 mm and a 2x barlow. Comet covers 1/4th FOV. Hint of mottling in outer halo on NE side. Central coma is still evenly distributed.
With 12.5 and no barlow. Comet covers 1/2 FOV.
With 12.5 with 2x barlow. Comet completely fills the FOV. Averted vision - the nucleus appears elongated, possibly a double that is not quite splitting.