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Showing posts with label Searchlight. Show all posts
Showing posts with label Searchlight. Show all posts

Sunday, 22 December 2013

20131221 - ISON Not Found + the start of a theory

Over the past few days two famous telescopes have been looking for C/2012 S1 ISON.

The Arecibo (the world's largest Radio Telescope in Puerto Rico) reported yesterday that they had found nothing. 

The Hubble Telescope reported late yesterday that they had found no trace of it. Here is a link to their results.

There may be a few bits around, but they would be less than 150 meters in size.

So there is no need to throw any life rafts, Just wreaths :( 

Why and when ISON started to break up is now the question that is being asked and various theories, which need to be tested, are being put forward. My personal theory - unproven - is that sometime in the lead up to the 13th November (perhaps a day or two before) the nucleus of the comet started to become unstable, whether a chunk broke away or it started to crack I do not know. The visible effect is shown in this image that SON@OSC took on the morning of the 13th November. If you look a third of the way along the lower tail you can see a discontinuation. +Padma Yanamandra-Fisher  picked up on this event as soon as she saw the image.



Over the next few days the comet physically changes as can be seen in the following image from the morning of the 15th .

The following day, the 16th, it seems calm down a bit (through cloud).



Morning of the 19th through thin cloud again!



The next event was noticed on the morning of the 22nd. +Charles Bell  pointed this out to me. towards the end of the displayed lower tail there is a branch off - looks like half a feather on an arrow. I think that a day or two before there was another major fracture to the nucleus.




This was the last time I saw ISON . I think by this time the nucleus was fatally flawed and came apart during its near encounter with our Sun.


It is important to recognise that the images of ISON represent only part of the history of the comet. They are, of course, an important resource, especially if and when other images can be added to the time line. I still have a number of images to process and perhaps some of those will add to the story.

Other data now needs to be brought together and analysed. A lot, but not all, of this data has either been captured by amateurs or is in the public domain. A number of amateurs have already started modelling this data, some of which at first glance supports my idea. Until I fully understand this data (and other data), myself I will not present it and only then with permission.

I will be looking to see what the professionals come up with. One thing about of astronomy is that there is always something new to learn.

Finally

After a cloudy night, this morning I managed to finds some holes in the clouds and brought the cameras into focus and at dawn take some flats.

Late afternoon we struggled up the observatory hill with the framework for the new roll off observatory to house the new telescope.

This evening is cloudy again :( which was disappointing as Search Light Observatory Network had received a request to record a stellar occultation which would been taking place now. Alas the observatory hill is covered with a damp cloud.

Friday, 29 November 2013

Is ISON Saying "“Reports of my death have been greatly exaggerated”?

Even while the Wake is taking place new images are showing something in an area where we expected to see, if not nothing, very little.

SOHO LASCO C3 2218 

If you look at 11 o'clock next to the solar cut off disk you will see ISON - or what remains of her. We will not know for a while what we are seeing, though the professionals are putting forward educated ideas. It could be that there are a number of pieces have escaped complete destruction.

SOHO LASCO C3

Thank you +Tavi Greiner of the CIOC_ISON Group for finding these and causing a few of us to the East of you to not go to bed when we had planned to. You have certainly brought a smile to a few people as well as causing people to scratch their heads.

In the morning I will be looking to see what has happened during the night - if I can sleep!



Sunday, 17 November 2013

Nothing today but most certainly More of Yesterday the 15th November 2013

After a few hours sleep last night I went up to the observatory to open up. The ground was covered in ice and frost and the clamshell was covered in a coating of ice. I pressed the open button and nothing happened - the clams were frozen. Pushed up on one side to break the seal and it opened. That was in fact the highlight of the observing session. By the time I walked back down to the house and sat down at my desk had sat down the sky clouded over and for the next couple of hours only caught a few glimpses of C/2012 S1 ISON.

So back to yesterday.

After Wednesday I thought it would be a long time before such excitement would come around again. I was wrong!

I had opened up the observatory a little late so only spent a short time on C/2013 R1 Love joy, (note to self must get round to processing those images). Then onto C/2012 S1 ISON. After moving the telescope slightly I took a one minute exposure to check I had as much as possible on the frame.





I looked at it and thought where is the second tail. Looked again and saw that there were multiple tails. Quickly changed the setting to a 3 minute exposure and binned 3- (basically that means that a 3 x 3 square of pixels is treated as a single pixel - bigger pixels mean more light captured quickly). Started to take the image - 3 minutes gave me the chance to make a quick cup of coffee :) - the image downloaded and I thought Wow! What has happened to it?



























I felt as though I was looking at an old woodcut or engraving. Just look at it and imagine if  it filled the sky as some great comets have in the past.

I sent this image along with a negative to CIOC_ISON for Padma to look at and also to Comet Watch for Neil.



























Negatives are very useful as they are easier on the eye for seeing the detail. To say that when people saw this caused some interest, would be an understatement.

From downloading the image from the camera to it being up for people to view was achieved in about ten minutes.  This enabled people to react to the change, either discuss what was happening or assisting in preparing to follow up.

To achieve this speed I do have to keep the processing simple. Flat and Dark frames have been applied, the background normalised, the image slightly stretched to bring out detail, in this case rotated 180 degrees so that north is up and then first saved as a positive then a negative and finally uploaded to the sites.

If you are a serious comet observer then you may wish to join CIOC_ISON and you are a Facebook user then click on the link.

While doing this more images were needed and I set of a cycle of LRGB image taking. This involves the camera taking multiple images, rotating through clear, red, green and blue filters. Twenty seconds per image. That was when the cloud came in and only nineteen more images were taken.

It was time for a quick cup of coffee and then shutting the observatory.

Between answering and asking questions I processed four of the last set of images to produce a colour image. Because these were short exposures the coma (head) of the comet looks smaller and there is less detain in the tail.



























You can though still see the multiple tails an yes the comet is green. During the rest of the day I continued to keep uptodate with the comet, taking part in a number of discussions and a number of other activities.

These activities including sending images to the Comet Section of the British Astronomical Association . Later in the day there was a report and ebulletin issued.

I also produced a montage based on the last seven days activity up to yesterday.



























Although simple to put together it went down very well with all the people who saw it.

I was asked during the day for permission to display a number of the images on various websites. I may cover this in a later blog.

Finally I did a prerecroded interview with Paul Harper of  Under British Skies
and this will be broadcasted on Sunday.  Although I will be talking about the comet the interview I was first asked about what is Searchlight Observatory Network. I only hope that I get it right. :) For more on the comet there is at least one other person covering it and that is +Padma Yanamandra-Fisher and I expect that she will be the highlight of the show. Padma is responsible for the CIOC_ISON Group on Facebook.

The CIOC_ISON Group is an a forum to provide support for professional and amateur comet observers to: share, discuss and collaborate on observations of comet ISON, as part of NASA's Comet ISON Observing Campaign (CIOC).

Well that is the description!  but it is a lot more than that.

Detailed information about the CIOC is located at: http://www.isoncampaign.org/


I finally got to bed twenty four hours after last in it.




Friday, 15 November 2013

ISON changes into a Broom Star - a quick uptdate

The weather was bad yesterday morning so no observing. It was very frustrating, people were reporting activity in the coma and all I could do was read other peoples reports :(

The comet is now naked eye - not by me :( I was racing to image what I could before the Sun came up.

Again I have been lucky and pointed the telescope at the right time at the right place and captured a change.

Let us look at the difference in how C/ISON has changed over the past seven days.

The change is quite dramatic. The first image shows it with a single tail, the next it has gained a second tail, the third it has changed a great deal as covered by a previous post and now it has taken on the form that one associates with 17th and 18th Century engravings of comets - the Broom Star. ...... and this has all happened in a week!

There will be more images later today. Click on the images below to see them larger.
.

Morning of 9th November
Morning of 12th November
Morning of 13th November
Morning of 15th November



















Wednesday, 13 November 2013

ISON and feeling happy :)

Just woke up from my siesta (well I did make do with just four hours last night) and saw on the CIOC_ISON Facebook Page :

ALERT: images from earlier today: from Tony Angel:
 maybe outburst - please image, take spectra ??
 Thanks Tony for the quick alert.... Thanks, Padma Fisher

CIOC_ISON: is the Pro-Am Collaboration for Support of NASA Comet ISON Observing Campaign (CIOC) via Social Media.

Click here to read Padma's article or visit the NASA Comet ISON Observing Campaign

I do know that I was not the only person to pick this up, but it still feels good :)