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In reply to: Exoplanet transits
Posted by TonyAngel at 10:50 on 2012 Nov 06
Hi Richard, I did ask Roger Pickard at the TA and VSS meeting if he would be including Exoplanets in his section (after all they do cause stars to vary :).I have read through Bruce Gary´s book and am slowly working through a couple of others. As you know the Czech Astronomical Society have a very good Variable Star and Exoplanet Section which runs their TRESCA Project, which includes the ETD – Exoplanet Transit Database. The organisation I am working with – Searchlight Observatory Network – has started submitting observations to them. The data I sent to them was collected from the observatory located on my farm which I operate for them. Upto now I have produced light curves of four exoplanets and only bad weather has caused a short halt. The setting up of the ETD must have involved a huge amount of effort and would take quite a long time to produce something similar, including all the utilities. Maybe it would be worthwhile considering forging a link with this organisation. They are far ahead of the AVVSO in this field.Most of the exoplanets that I have been observing have a change of magnitude in the range of 0.02. The great majority of exoplanets have a change of magnitude far less than this and require specialised software such as Mira or better equipment. The observing runs tend to be in the two to three hours, taking an image every one minute, so a good mount and guiding system is required. Yes a small(ish) telescope can be used. After all the SuperWasp project were just using Cannon lenses. It would be helpful for there to be a talking shop for this. There is a Yahoo Group but there is not much discussion on it. There are some good papers in the MNRAS and in the arXiv database.Perhaps a starting point would be to have a dedicated discussion area on the forum for exoplanets.
In reply to: Exoplanet transits
Posted by Richard Miles at 09:37 on 2012 Nov 06
Morning Tony,Several folk are doing exoplanet transits and a paper by Darryl Sergison entitled "High precision photometry: detection of exoplanet transits using a small telescope" was accepted for publication a few months back so should be appearing in the Journal soon. Hopefully Darryl’s fine work will encourage many others to observe these transit events.I suppose one implied question in what you write is: "Should we coordinate the work on exoplanets that BAA members are doing?" The observing methods used have a lot in common with eclipsing binary observations and also with determining asteroid rotational lightcurves. I don’t believe that exoplanet, work is so different that it requires the setting up a new observing section however. We could from time to time highlight people’s work in the Observers’ Forum part of the Journal as a start.Do members have any views, I wonder?Richard Miles
In reply to: 168P/Hergenrother – recent fragmentation event
Posted by Denis Buczynski at 10:07 on 2012 Nov 03
There has been further evidence of the break up of this comet with news of observations from the Mauna Kea in this press release. "Using the National Optical Astronomy Observatory’s Gemini North Telescope on top of Mauna Kea, Hawaii, we have resolved that the nucleus of the comet has separated into at least four distinct pieces resulting in a large increasein dust material in its coma." http://www.jpl.nasa.gov/news/news.php?release=2012-349Denis Buczynski
In reply to: 168P/Hergenrother – recent fragmentation event
Posted by Nick James at 19:14 on 2012 Nov 02
The WIYN blog image of the 168P fragment has been removed from their site but the Faulkes Telescope team have put it on their latest blog posting here:http://bit.ly/QZlt7hThis post includes some more recent images of the fragment taken with FTN. Richard Miles has processed these to show the features more clearly:http://www.britastro.org/~rmiles/Documents/168P_2012Nov02.pngI obtained an image last night with a much smaller telescope (Celestron 11) so there is no sign of the fragment as it is well below the resolution of that system. Even in that aperture the comet is an interesting object:http://www.nickdjames.com/Comets/168p_20121101_ndj.jpgNick.
Posted by Nick James at 21:09 on 2012 Nov 01
This comet has recently been in outburst but, more excitingly, a fragmentation event has been observed in large telescopes. This was first seen by a team using the Faulkes Telescope (Giovanni Sostero, Nick Howes & Ernesto Guido):http://remanzacco.blogspot.it/2012/10/splitting-event-in-comet.htmlRichard Miles then reprocessed these images to show the fragment clearly:http://www.britastro.org/~rmiles/Documents/168P_20121022-26.pngI obtained an image using the 0.8-m Mt. Lemmon telescope (via Sierra Stars) on the morning of October 30:http://www.nickdjames.com/Comets/168p_20121030_ndj.jpgbut it doesn’t show the fragment. There does appear to be a bifurcation in the near-tail around 4 arcsec and p.a. 150 deg from the brightest pixel position which may be associated with this event but there is no obvious sign of the fragment itself.An image with the 3.5m WIYN telescope does show it clearly:http://podideployment.blogspot.co.uk/2012/10/a-comet.htmlIt is unlikely that this will be visible in small telescopes since a high resolution and very good seeing is needed but it is definitely worth keeping this comet under observation.Nick.
Topic: Three Telescopes For Sale
Posted by David Mottershead at 11:25 on 2012 Oct 27
HelloI have for sale the following telescopes:Meade LX90 UHTC (the classic 8 model), GOTO mounted, Autostar hand controller, 9×50 finder scope and 26mm Meade lens, plus all original manuals. The scope also comes with a Crayford style 10:1 2 focuser, flexi dew shield and Hartman mask. Please note, the scope has a small dint towards the lower underside of the tube body, but which does effect the scope at all this is cosmetic only. Optics are excellent. £700 o.n.oCelestron NexStar 102mm SLT refractor telescope, with GOTO mount, red dot finder scope and complete with all manuals, discs and lenses as originally supplied. £180 o.n.oSkywatcher Startravel 120mm short tube refractor telescope on EQ3-2 equatorial mount, (this is the latest version in the diamond black and white livery), the supplied red dot finder scope and the upgrade 9×50 finder scope, and complete with dual axis motor drives, manuals, slow motion controls and lenses as originally supplied. £280 o.n.oIf interested in any of the above, please contact me for more details/photos at david@dmottershead.co.uk I am selling these as rationalising my telescopes, and buying a large Newtonian reflector!!Many thanks.
In reply to: Selling Stars! – Star name marks observatory openi
Posted by Nick James at 20:35 on 2012 Oct 10
Bizarre isn’t it.Perhaps the BAA should take this up as a money-making opportunity? I have the USNO B1.0 on my hard disk here and that has a billion stars in it. We could sell stars online for a few quid each and we could absolutely confirm that no one else had the same BAA star (apart from the odd catalogue duplicate). Variable stars and other stars of more interest could go for more. No money back would be offered for stars that went supernova but we could offer observing sessions for particularly rich and/or stupid mugs who might like to see their star through a telescope.What could possibly be wrong with that?Nick.
Posted by TonyAngel at 08:31 on 2012 Oct 10
Anyone know who was responsible for "buying" the star?Press Association Fri, Oct 5, 2012A star has been named in honour of Scotland to mark the opening of the first public observatory at the UK’s only designated dark sky park.First Minister Alex Salmond was handed a certificate for the "Alba" star, which means Scotland in Gaelic, as he officially opened the Scottish Dark Sky Observatory.The centre is at the edge of Galloway Forest Dark Sky Park on the Craigengillan estate, near Dalmellington, Ayrshire, and was founded by estate owner Mark Gibson.The observatory’s dome was designed in, and flown over from, Australia and features a rotating, retractable roof to enable viewing through a robotic telescope. It also has a lecture room and an outdoor elevated deck for naked-eye observation.East Ayrshire Council said it hopes the centre will attract visitors from across the world, increasing tourism and helping to regenerate the area.Viewing will not be restricted to night-time, the council said. Daytime visitors can experience real-time links with observatories in Australia and other parts of the world. The observatory will also be used as an educational resource for schoolchildren and students.Mr Gibson said: "This is a day of celebration and the achievement of a dream. What we have here is something incredibly precious and incredibly exciting. This is the only public observatory within a ‘gold tier’ dark sky park in the world. It will inspire people of all ages and backgrounds with a sense of wonder at the vastness and beauty of the heavens."Galloway Forest Dark Sky Park, which spans 300 square metres, was awarded its status by the International Dark Sky Association in November 2009 during the International Year of Astronomy. The observatory will not be open to the public immediately because the telescope is still being calibrated.Mr Salmond described the observatory as "no less than stunning".He said: "Curiosity about science and a passion for learning more about the world around us are the cornerstones of ensuring the next generations of innovators upon whom Scotland’s future depends."
In reply to: Stacking images
Posted by Graham Relf at 15:59 on 2012 Sep 09
There should be no difficulty, provided that there is a significant overlap between the frames, so that most of the brightest stars in one frame are also visible in the others. The scale needs to be similar too – ie, the same focal length lens or optical set-up in the telescope for all frames.My own software works by looking at the patterns of connecting lines between the brightest stars (the 24 brightest, unless the user changes that number). They do not all have to match.Stacking is done into an accumulator image having 32 bits per channel, so that adding up brightnesses does not cause them all to saturate (reach the 16-bit limit, which is the depth of the original images). For deep sky work it is important to keep the 32-bit depth for subsequent processing, otherwise you are throwing away the possibility of pulling out the faintest detail from the background. So if the stacking software can take as input files having 32 bits per channel, you will not lose anything by stacking two or more already stacked results. That necessarily means saving the results as FITS files because 32-bit TIFF files (aimed for importing into Photoshop) use 32-bit floating point rather than integer values and so really have only 23 bits per channel resolution (allowing for wasted sign bit).If you cannot use 32-bit FITS files as input to the stacker you would be better off stacking all of the original 16-bit frames in one sequence, even if from different nights.
Topic: LUNAR IMAGING WITH A DSLR
Posted by M C Butcher at 10:34 on 2012 Sep 04
I conduct my imaging with a stock Canon 40D. Within those limitations I attempt the best imaging results of which I am capable. My telescope is a 8" Meade LX90. Whole disc lunar is not a problem and I use a f/6.3 focal reducer to shorten exposure time and nicely encompass the whole lunar disc in the single exposure. For individual craters I increase the focal ratio and magnification by performing eyepiece projection using a variable tele-extender. However, this set-up is very susceptible to poor seeing, vibration and any one of other problems and consequently my results are very hit and miss – more miss than hit! The 40D does not have a video capability so I take many images employing the camera’s 2 and 10 second self-timer together with mirror lock-up (to reduce vibration from the mirror movement). Is this the best I can do? Should I be attempting to stack the images, certainly when I try I do not get a crisp result and the sole value of taking lots of exposures is simply to enable me to choose the best. My stacking software is Images Plus, should I be using a different software for this purpose?I appreciate that the best solution is to use a web cam, a CCD or a video camera, however, all of those involve a computer near the telescope and my set-up does permit this. It may of course be that I am already doing all I can to get the best detailed images of craters in which case so be it. Can anyone offer any practical advice?Martin Butcher
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Posted by Denis Buczynski at 13:00 on 2012 Aug 25
Congratulations to Tom Boles who has made his 150th SN discovery with confirmation of a SN in NGC 1213. Details and images are to be seen on David Bishop’s Latest Supernovae Website.There has also been a discovery of a SN in IC2166 by Dave Grennan of Dublin (his second) which has been confirmed by spectroscopy taken by a team using the Nordic Optical Telescope. A link to the details can be found on the VSS Website.
In reply to: JBAA papers
Posted by Paul Abel at 18:39 on 2012 Aug 01
Dear Steve,I’ve had a number of papers published in the JBAA and I have to say I have found the process to be both fair and helpful. Two recent papers spring to mind: first the paper I wrote which discusses my experiences of using the Alvan Clark refractor at Flagstaff, Arizona. I think this would fall into your category of personal experience. I think this sort of thing can still be regarded as a paper since, although it involves a subjective experience, that experience depends on objective facts which appear in the paper(like telescope stats, observing details and so on). When I submitted the paper, I got some useful comments back and suggestions which did help tighten it up.More recently I co-authored a paper with Damian Peach about observing Uranus. This was more of a scientific paper. After submission there were some disagreement between the referees and ourselves but these were sorted out in a way which suited everyone and it seemed to me that the referee process was robust produced a result which allowed the paper to be published.Based on these experiences I cannot therefore agree with with your interpretation that the process is not fit for purpose. I also think that the quality of the papers in the JBAA is uniformly good, with a diverse mix appearing the same journal (other journals could do well to see to this!) I think the above suggestion is a good one, and that perhaps is a line of dialogue to explore. Certainly a council discussion of it is a good idea I think.Best wishes,-Paul.
In reply to: Robotic Telescope Project Web Page Updates
Posted by Grant Privett at 22:36 on 2012 Jul 05
You would be amazed how few decent images are available of variable nebula. And even then when I have emailed the owners asking for FITS versions I get no reply.
Topic: Telescope Sale
Posted by Anthony Stone at 12:05 on 2012 Jun 17
For Sale8" Meade LX50 Schmidt Cassegrain TelescopeWith Heavy Duty Field Tripod + Equatorial Wedge6x30 Finder 1 Eyepiece Basic Telescope 14 years old Aprox;£550 Buyer Collects.Tel: Tony 01179676750 ( Bristol).
Posted by David Mottershead at 12:29 on 2012 Jun 11
For Sale here is a Celestron NexStar 102 SLT. In as new condition, a superb 102mm wide field refracting telescope, (focal length 660mm, multi coated optics) mounted on a pre-assembled, fully adjustable steel tripod (motorised alt-azimuth) with GOTO computerised handcontroller (over 4000 objects in the database), featuring Celestrons ‘Sky Align’ star/telescope alignment system, quick release accessory tray, 1.25" star diagonal, (but can take 2" diagonals and lenses – includes 2" to 1.25" adaptor) Star Pointer ‘Red Dot’ finderscope and fully complete with instruction manual, 9mm and 25mm Celestron lenses, ‘The Sky Astronomy Software Suite’, (Level One, v5), ‘NexStar Observers List’ software (v 2.0.2c for Windows) which allows for basic control of the telescope via a computer. This is a great telescope, providing excellent views of the night sky. Easy to setup and use, this is a robust, sturdy and stable unit, while still being fully portable. Bargain at only £260 o.n.o.Please contact David through the forum via PM or on 0796 9216756
In reply to: Transit of Venus
Posted by Callum Potter at 15:23 on 2012 May 15
Hello Alex,thanks for note.It is a very good point that with the low Sun, and perhaps some cloud on the horizon there might be a temptation to view the Sun through the cloud with an unfiltered telescope. But this would be a very risky thing to do – even a fraction of second break in the cloud could let enough IR through to permanently damage your eyesight.I think I will expand on this on the Observing section of the page.Best, Callum
Posted by Paul Jenkins at 12:57 on 2012 Apr 22
HiI have a Celestron Edge HD 9.25 telescope for sale complete with baader steeltrack focuser£1350
In reply to: Guiding
Posted by Paul A Brierley at 06:46 on 2012 Apr 21
The lack of suitable guide stars can be a problem with a small telescope. And this was the reason for using my 9×50 finder. With my QHY5. I don’t have any trouble finding a suitable guide star. And the guiding is very accurate. I was guiding at 2.5 seconds last week-end. And imaging at 1200mm with 300 second subs.
Topic: eric
Posted by Americo Watkins at 22:06 on 2012 Mar 20
Does anybody know of a suitable manufacturer or supplier of a telescope cradle to mount A c14 edge to a paramount ME other than Andy Homeayer in the USA or Orion Optics UK. Also their experiences with either of the cradles mentioned. I’m sure Andy’s is a good one, but there are transport costs involved from the USA + import duties.PS I may also like to mount additional equipment (‘scopes) to the cradleMany thanks,Eric
Posted by Paul A Brierley at 09:39 on 2012 Feb 26
I have a question for every Canon user on here.How good is the above, for astro-imaging?I have been for a while now, considering up-grading my Atik 16ic to a 314l+. However. I can’t really afford the asking price of a new 314l+ CCD camera.Recently. I have been very impressed, with the number of very high quality Canon, DSLR images. And It started me thinking.I already own a very good CCD camera already. And wonder whether. A modified Canon 1100D as sold, Astronomiser, might be a better solution, and cheaper one. For large format colour imaging.Pros.Full colour. With software control, of all camera settings. Including Bulb.And.Excellent colour response.Cons.The camera isn’t cooled. So I will need darks and flats. And the camera can only be used for astro-imaging.I can still use the Atik 16ic for galaxies and other smaller subjects.But-I would like to take, wide field images with a DSLR. Of larger nebulae. NGC 1499-7000 etc.Using H-Alpha and my little APO. I also want to use it, with my Orion O 200-800 F4 "astrograph". For imaging galaxies and star cluster’s.I would welcome any advice from Canon camera user’s, on this forum.I am particularly interested to know, what I need to couple the camera to these telescope’s.And. What comes in the box.
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