20140110 - Exoplanet Observing Preparation plus some Comet Observations and Images

I had hoped to have been writing up a successful observing run today, but it was not to be. :( However I did manage to put the time to good use and none of the research I carried out for it is wasted. :)

Once the internet was back on I checked the weather for the coming week. It was not looking good at all. It looked as though there was going to be some clear patches last night, then a couple of days of cloud and rain, then a clear night starting at midnight on Saturday and then four days of either cloud, rain or snow!

I checked against my lists of exoplanets to observe to see what transits and secondary eclipses were due to take place last night and created a potential observing list.

Find The Stars

Now the great majority of exoplanet host stars are known by the name of the survey that discovered them, then a number to indicate the order that they were discovered and finally a letter to indicate the planet. The first planet to be discovered orbiting a star is "b", the second "c" and so on. There are exceptions to the rule and when appropriate I will mention them. :)

So the starting point is to identify the star so that I have something to do a "find" or "locate" when using the planetarium programme I use to control the telescope.

The best way to do this is by using an online astronomical database called SIMBAD . It is a fantastic toolset and one that I will mention quite a lot in the future. Today though I will just cover some of the tools.

One of the query options is by identifier and this is the one I start with. It does not have all in them so I will cover a few other options as well. Let us say that the exoplanet I want to know about is CoRoT-1 b. I key in CoRoT-1 - after all it is the star I am interested in. This brings up the correct page. I then scroll down to the Identifier Section where it lists all the other names it is know by. One of the identifiers listed is GSC 04804-02268. This is ideal for my purpose as GSC (Guide Star Catalogue created for the Hubble Space Telescope) is one of the catalogues supported by the SKY programme I use to control the telscope.

If this does not work then I do a simple Google/Yahoo/Bing search on the exoplanet name and GSC and normally that will pull up a paper or a Wiki that will give me the answer.

The last option is again using SIMBAD, but instead of using the Indentifier Query I use the by Coordinates Query and enter the RA and DEC  and this should bring up the star.

This chore is reducing as I have a file that I keep updating each time I observe a different exoplanet.

Location of Star

I know time range that I need to observe (this is in the original observing list) so the next thing I need to do is check which parts of sky these potential options will traverse, (of course it is the Earth that is revolving on its axis and not the sky). I use the SKY programme to help me see where in the sky they will be at different kinds. I eliminate from the list all those that cross the Meridian (imagine a line starting directly to the South, going up overhead, through the Pole and to directly North). This is because the type of telescope mount here is a German Equatorial Mount  which is not capable of tracking across the Meridian.

Prioritise

I then look at what is left in the list. Unless there is any with a special priority I then decide which are the best ones to observe. I take into account altitude, where the Moon is, the brightness of the star, the range in potential magnitude variation during the transit and few other odds and ends LOL `(the odds and ends are actually a blog in their own right as it includes comparison stars and guidestars)

Finder Charts etc

The final thing I can do before the evening is to download any finder-charts I need. Many of the steps taken only have to be done once, so once a you have observed a specific exoplanet, the next time most of the preparation work has been done.

Back to Last Night

On my list I had four options, two rising in the East and two setting in the West. The weather forecast had mentioned a strong wind from the East, so I had a walk up to the observatory to see how strong it was. It was quite strong so I scrubbed the two in the East off the list. I waited a couple of hours for the first in the West, during that time it was clear to the South West, but guess what the cloud came in. The same thing happened at four in the mornings so I packed up and went to bed :(

Hangout about Exoplanets

Talking about exoplanets LOL. On Wednesday evening I attended a google hangout on exoplanets involving Astronomy and Discovery   magazines and chaired by +David Eicher Editor of Astronomy. It was great. No dumbing down, interesting and suitable for all. I look forward to more of them. You can even
ask questions :) so I did :) . I am quite new to this hangout idea, so not sure how long they are kept on line. Here though is the Link to a recording, but how long it will remain live I do not know.Well worth an hour of your time.

While I was waiting around last night

I processed a number of images I had taken a few days ago of some comets. Below is a selection of a few of them. The one good thing about comets is that in a normal exoplanet observing night there is normally time to slot in before, between and after, a few images of comets.  

290P Jager 2014-01-06 20:33 N Mag 13.7
4" Pentax at F4 ST8 clear
SON@OSC
The small boxes - viewing left to right show the progress of the comet over 30 minutes covering about 20 arc seconds.

C/2012 X1 Linear 2014-01-07 04:58 N Mag 10.7
4" Pentax at F4 ST8 clear
SON@OSC

C/2013 R1 Lovejoy UT 2014-01-07 05:46 N Mag 8.3
4" Pentax at F4 ST8 clear
SON@OSC

20131220 - All change in the Observatory

As I mentioned in the previous Blog it is time for exoplanets again.

What is an exoplanet (or extrasolar planet)? It is a planet that is in an orbit around a star other than our own Sun :)

I received a few days ago, along with the other Searchlight Observatory Network Observatories, the agreed list of targets and time table from Professor +Svetlana Berdyugina at Kiepenheuer-Institut für Sonnenphysik .

Svetlana has been observing exoplanets for a number of years. It was Svetlana and her team that discovered, a number of years ago, that a planet (HD 189733b) in orbit around HD 189733 is blue. This was later confirmed this year by Hubble observations.

There are a number of different ways to discover and monitor exoplanets. The current project involves known exoplanets using a technique called Exoplanet Transits. This only works with systems that are near to edge on to us. The observation process involves measuring the change in brightness of the host star when an explanet passes in front of it. The techniques involved are similar to those used for variable star observing. I will write, in the near future, a number of Blogs covering the various methods of discovering and monitoring exoplanets :).

Ideally I should have changed the telescope configuration and started some test runs a few days ago, but after a few months of overall good observing nights the weather changed. We have had clouds, we have icy rain and lots of interuptions with the power.

Yesterday's driving rain stopped me from opening the observatory so with the alarm set early I went up to the observatory to check it out. Apart from a few small wet spots and the need to reset the power everything was OK. It was still fairly cloudy but with holes so I managed to see some stars for the first time in days. It was not suitable for imaging properly but decided to take some images of Comet Lovejoy before changing the configuration.

After these were taken it was time to start to change the configuration.

For the past couple of months the ST8 CCD Camera along with its filter wheel has been on the 4" F4 Pentax refractor and the ST7 CCD Camera was on the C14 F11 SCT.

I now needed to swap the cameras over and also reduce the focal length of the C14 by putting in a focal reducer and once done rebalance the telescope and check that the cable will not get tangled up, (four power cables and four data cables!).

That is the easy bit done! The sky or should I say the clouds stopped most other things being done until this evening and daybreak - providing that it is clear.  So hopefully I will be able to refocus the two telescopes and take new sets of dark, flat and bias frames.

N.B. For none astronomers I promise to do a Blog posting in the next few days explaining the reasons why I needed to change the configuration and what are the effects.

There are a number of jobs I can do during the day, some of which are already under way, including producing an observing timetable.

It is now starting to get dark. There are thick clouds on the horizon and thin cloud overhead. Providing the cloud overhead does not get much thicker I will be able to finalise the configuration, otherwise it will be the case of getting up at four in the morning to check if the cloud has gone and if it has to do the finalisation then.

As there will not be much to show image wise with exoplanets, I will be showing images of various objects that I have yet to process, or will be able to take when exoplanet observing is not taking place.

Other work in progress

I am in the middle of getting another observatory up and running. I have building a roll off structure for it and late afternoon we got it up to the observing area ready for cladding. Pictures tomorrow.

The other day

I mentioned in the previous Blog that a drop in power stopped the telescope mount from working for an hour or so. What I did not mention was that the computer and cameras did not stop.

The following image was taken at ten o'clock at night with just moonlight. It will give you an idea of the power of the telescope (4" refractor) and a time controlled CCD camera :) The distance to the buildings is about three miles.

20131211 - A catch up on comet images

As I mentioned in the last post, the reaon for lack of entries it is not that nothing has been happening, but the reverse!

A comment to the previous post exclaimed surprise at the time that processing the images take.

Let us go through a simple outline processing the comet images that I now follow. I will cover an observing run another time.

OK then, I have finished and observing run and closed down the observatory. What next?

On the computer there may be as many as 500+ images from the observing run all held in a directory named after the evening before's date in reverse order. Today is the 11th December 2013, so the observing run that could have started yesterday evening and finished at daybreak today so the directory would be named 20131210.

I then create a number of subdirectories named after the objects I have imaged. Where I have imaged the same object in two different ways then I create two subdirectories. Into these subdirectories I copy the various groups of files. There could be up to a hundred or more image files in each subdirectory.

The images in each of the subdirectories need to be reduced (or calibrated). Data reduction This is to take out inconsistencies. If you want to read more about it here is a link that explains the basics. The reduced files are put into a subdirectory - we do not overwrite the original files as we need to keep these.

After this has been done what happens next depends on what type of observations have taken place on different classifications of objects.

I will now describe what I do for single framed images of comets. My starting point is a folder of reduced images of a comet. There maybe 100 images and at a quick glance you would think that they are all the same, but there are not. A comet is moving against the background of stars. If we looked at each of the images carefully you would note the comet, especially as it gets nearer to the Sun will be in a slightly different position against the stars.

We are interested in the comet - not the stars. Let us say that each of the images is a 10 seconds exposure. We have a hundred and we need to overlay each of the images so that the comet overlays itself and not the stars. A number of programmes can do this, but I have not found one better than Astrometrica . Not only can it stack the comets - called Stack and Track the programme can many other things including astrometery and photometry (where is it and how bright is it).

This exercise leaves me with a single combined image that I can save and its brightness (magnitude).

I can now load this image into another programme and prepare it for submission.

At the moment some of the images are shown here, sent to the British Astronomical Association, shown in a few Facebook groups including Comet Watch and CIOC_ISON and also shortly to the University College London.

We do not delete any of the observations because you do not know when they may be of use. A good example is the UCL where I will be going back in time to find images that meet their needs.  


Here then is a gallery of some of the images taken since the last images until the 7th December:


SON@OSC (Searchlight Observatory Network at the Observatorio Sierra Contraviesa, Granada, Spain)
Observers Tony Angel and Caisey Harlingten
4" F4 Refractor ST8 Clear bin 1x1
FOV 115.5 x 77.7 arcmin
North at top

C/2013 R1 - Lovejoy - 2nd December

C/2013 R1 - Lovejoy - 2nd December

5th December

C/2013 R1 Lovejoy - 5th December

C/2012 R1 Lovejoy - 5th December

6th December

C/2012 R1 Lovejoy - 6th December

C/2012 R1 Lovejoy - 6th December

7th December

C/2012 R1 Lovejoy - 7th December

C/2012 R1 Lovejoy - 7th December

C/2012 X1 Linear - 7th December

C/2012 X1 Linear - 7th December

C/2013 V3 Nevski - 7th December

C/2013 V3 Nevski - 7th December

2nd December morning - Comet C/2013 R1 Lovejoy and C/2013 V3 Nevski and a little on ISON

After nearly a week of cloudy skies I had a good observing run yesterday morning :)

I first went to Comet Lovejoy. I was using the wide field 4" F4 Refractor along with an ST8 CCD Camera. This comet is getting better, brighter and clearer each time I observe it. It was discovered by Terry Lovejoy in Australia, this is his 2nd Christmas Comet and I will say more about him in another post. He is most certainly an astronomer's astronomer. It is visible to the naked eye and well worth looking for.

I had decided that I wanted to image the whole of the comet, which because of its length meant that I would have to take a series of images, starting with its head and working along the tail.

I took them between UT 2013-12-02 5:00:34.063   and  2013-12-02T05:14:50.329 . Each image has an FOV of FOV 116.5 x 77.7 arcmins - north is on the left! You really need to click on the image to see it better!

I took seven images.each 1 minute exposure - no binning - and overlaid them.

Using simple trig the comet as displayed is a touch over 5 degrees in length. It was not until I processed the images that I realised that I had not captured the full length of the tale. I was not able to do a retake this morning, so fingers crossed for tomorrow, but it will need this evening's winds to drop. :( If it is clear then I will do x2 binning but keep the exposure time to 1 minute. That will bring out the furthest parts of the tail. As this will produce smaller images it will make it easier to create the overall image. The comet is moving against the back drop of stars, so I have to move onto taking the next image directly after the previous one, (partially guessing I am moving the right way :) ). so that there is no perceptible change.

As well as the above image I took a series of shorter exposures of the comet head. These exposures are between half a second and ten seconds. I also took a colour image as well. These are still to be processed. I used a series of the shorter images with Astrometrica by Herbert Raab to get a N Magnitude of 8.8

The next comet I images was C/2013 V3 Nevski. It is quite recently discovered - 6th November - by Vitali Nevsky using an 8" F1,5 reflecting telescope. Vitali is no stranger to discovering comets. He, along with Artyom Novichonok, discovered Comet C/2012 S1 ISON.  When discovered it was magnitude 15.1. Fellow CIOC_ISON member +Charles Bell  imaged it on the 14th November and its N Magnitude was 15.6. There had been reports that it had brightened to about magnitude 10 however when I imaged it yesterday morning the N  magnitude was 14.7.

Here is my image taken UT 2013-12-02 5:58:27.454 - FOV 116.5 x 77.7 arcmins - north is at the top. The comet is to the right of centre. It is still quite small, though a short tail has been observed.

I then took a few of Comet Linear and I will put these on next time. After Linear I did try for a couple of others, but my processing has not yet brought them out. They were a bit fainter.

To complete the observing run I finally I went to the the Eastern Horizon to see if I could capture the poor remains of C/2012 S1 ISON, but it was too bright - the sky that is, not ISON. If the weather is OK I will trying tomorrow morning.  Is there anything to see? We just do not know yet.

Before I finish for the night I must mention a particular hang out that you may wish to look at. It is the Comet Festival South Bend Today I watched yesterdays and today's editions. They have good astronomers on there and today's edition - hosted by +Chuck Bueter had +Pamela Gay , +Karl Battams and CIOC_ISON's +Padma Yanamandra-Fisher  (heck I hope I have the links right - if I have not - sorry!). Yesterday's edition was great as well, especially as it had my favourite astronomer, +Alex Filippenko, on.

C/2013 R1 Lovejoy and its tail Today

I had meant to be publishing a few of yesterday's images of Lovejoy - those will have to wait :) When I saw how the imaging of today's Lovejoy was going I thought yes - another Tail :)

Composite taken 25/11/2013 at 05:51:22.625 and 05:58.53.968 GMT (UT)
Purposely over exposed to show tail.
Each image FOV 116.5 x 77.7 arcmins - north is up.
SON@OSC (Searchlight Observatory Network at the Observatorio Sierra Contraviesa, Granada, Spain)
4" Pentax Refractor at F4, SBIG ST8 with clear filter. 1 minute exposure binx2 Observers Tony Angel & Caisey Harlingten

Little text today - so just enjoy :)

Observations of Tuesday morning 11/11/2013

Written 12/11/2013 started whilst observing.

Not sure which is more stressful; chasing the comets to image before dawn, processing the most interesting images or thinking of what to write on here :)

Certainly chasing the comets is getting more hectic as drop lower in the sky and it becomes a race to beat dawn.C/2013 R1 Lovejoy is bright and high in the sky, in fact I realised after the fact that I need to look at bringing down the exposure time for Lovejoy.  C/2012 S1 ISON is still high enough to get reasonable images, but 2P/Encke and C/2012 X1 Linear are getting quite difficult.  Today will be the last time I will try - if I have time - for a colour image of Encke and Linear.

All images were captured using the SON@OSC Observatory (Searchlight Observatory Network) 4" Pentax F4 Refractor and an ST8 CCD camera

Here are some of yesterday's images.

The t(r)ail on Encke is still very distinct and some 150 arc minutes of it are visible

2P/Encke

2P/Encke

Linear is getting quite faint, especially now dawn approaches. It is still possible to see the what is left from the recent outburst. 

C/2012 X1 Linear

C/2012 X1 Linear

I expect that this will be the final colour image.

he

C/2012 X1 Linear

The second tail of ISON was first observed a couple of days ago. This was the first chance I have had to image ISON and capture the two tails.

C/2012 S1 ISON

C/2012 S1 ISON

The two tails of Lovejoy are quite clear. There seems to be, below the other two tails, either a third tail starting or a minor outburst. 

  

C/2013 R1 Lovejoy

C/2013 R1 Lovejoy

I will start the observing report of this morning's observations soon. The tails of ISON have changed so I will want to get an image on here soon. :)

Another tail - this time C/2013 R1 Lovejoy

Just a shot blog today (11/11/2013). As Lovejoy is now the brightest comet in the sky by far I thought I would see if how much of the tail I could image. It was soon obvious that the tail extended beyond the width of the image - some 115 arc seconds, so I took a second and third overlapping images and found that two overlapping images could pick up all the tail capable of being captured by the current SON@OSC set up for wide field imaging - 4" F4 Pentax refractor and an SBig ST8 ccd camera.

The following images are not pretty pictures - the aim is not for beauty but for detail. That is not to say you cannot have both beauty and detail - the images of @Damien Peach belay that idea, however in this instance I needed to really stretch the image to bring out the ion tail.

First Image - showing coma and tail

Second Image - showing tail

Third Image - no tail found

Joined images one and two together.

I have seen one other image that shows the unusual detail in the second image.

Comments are welcome :)

More on Friday Morning's Comets plus Saturday Morning's Comets - that quartet again!

On Friday 08/11/2013 I wrote a little about 2P/Encke and that day's imaging of it. Here are some other images I took that morning.

C/2012 S1 ISON

C/2013 R1 Lovejoy

C/2013 R1 Lovejoy Negative

C/2012 X1 Linear

C/2012 X1 Linear Crop

Saturday morning - 09/11/2013 - covered the Quartet - Again!.

First 2P/Encke. As there was a fair amount on interest in its trail I spent as much time as possible on imaging this before dawn came.

What follows are four versions of the same image. The first is the regular image. The second is the negative. The third is a stretched regular and the fourth a stretched negatve. In the final image you can really see the meandering trail.

2P/Encke

2P/Encke

2P/Encke

2P/Encke

Below is C/2012 S1 ISON.  This is still not developing very much, though I did see an image that was taken 24 hrs after this one and a second tail has now clearly appeared. I will be trying for this tomorrow morning.

C/2012 S1 ISON

C/2012 X1 Linear continues to be fairly bright after its outburst.

C/2012 X1 Linear

C.2013 R1 Lovejoy is really becoming the star of the show. It continues to brighten and is well ahead of ISON. Where as ISON is difficult to see in 10x50 binos, Lovejoy is now being seen with the naked eye.

I used four different method of processing Lovejoy to see if I could bring out more detail. I then stretched each one.

Process 1.

Process 2

 Process 3 

Process 4

All the images were taken using the Searchlight Observatory Network Observatory here in the Sierra Contraviesa, Granada, Spain at an altitude of 4,500 feet. The telescope used is a 4" Pentax F4 refractor and the camera is a SBig ST8 . All the images, with the exception of the cropped Linear are FOV 116.5 x 77.7 arcmins

There was no observing on the morning of Sunday 10th November due to my wife going to England for a week or two. I thought it would not go down too well to open the observatory while she was getting ready to leave :)

In the next blog I will include some objects that are not comets :)