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Posted by Paul A Brierley at 07:06 on 2013 Jun 22
I’m very pleased the Association in conjunction with Manchester AS. Have seen fit, to host a meeting in my local area.I’ll be their manning the Macclesfield AS club stand.
Posted by Martin Mobberley at 10:35 on 2013 Jun 21
Nick,>I suppose because these planetarium packages are not downloading data in real time at best all they can do is plot the path rather than give minute by minute positional data.<Downloading data in real time isn’t the issue when it comes to knowing where the NEO is. The first issue is the accuracy of the orbital elements used to calculate the NEO’s position. For brand new NEOs these elements will be very rough, but with more measurements of the NEO’s position, by observers such as Peter Birtwhistle, the orbital elements become far more accurate. Planetarium packages can easily calculate the position for each minute, but when the object is close to the Earth a number of traps lie in wait. If the object is so close that Earth’s gravity starts to play a major role it is better to use the MPC ephemeris position, set for your location on Earth. Planetarium packages work perfectly well until an object is extremely close to the Earth.If geocentric coordinates are used (that is, the observer is assumed to live at the Earth’s core) the object’s position will become increasingly inaccurate as the object closes in….. When CCD fields of view can be aquarter of a degree or smaller this can lead to an object being missed.But downloading data in real time is not the issue, just having accurate orbital elements (these are often updated daily for critical objects), stating your position on Earth accurately and, for the closest NEOs, having software that can cope with an object influenced by Earth’s gravity….for very close NEOs the MPC predictions will be the best.Martin
Posted by Nick Atkinson at 19:59 on 2013 Jun 20
Martin,Thank you this. I have sky X and I have now found out how to enter the orbital elements. I did manage to image 1998 QE2 on 2/06/13 but failed on subsequent nights despite having the co-ordinates published by Richard Miles. I suppose because these planetarium packages are not downloading data in real time at best all they can do is plot the path rather than give minute by minute positional data.Nick
Posted by Jeremy at 19:54 on 2013 Jun 18
Me too, Gary. It’s particularly welcome to have a BAA meeting in the north-west.Go well!Jeremy
Posted by Steve Holmes2 at 01:09 on 2013 Jun 14
This image has a number of interesting aspects:-1) The track of Envisat across the sky as shown by the stars you mention is pretty-well parallel to that of Terra as shown on Heavens-Above. This confirms that the actual orbit of Envisat is polar, as for Terra, which is quite usual for an earth-observation satellite.2) The brighness profile of the flare is totally different from that of an Iridium flare or of the one I saw. This one seems rather more of a "flash" than a flare: Iridium flares tend to build up and die down fairly steadily over a period of about 30sec. The occasional one has a very bright central portion (when you’re close to the "centre line") but still has the steady build up and down. The Envisat "base level" is much less bright than for an Iridium flare.3) The Envisat image shows a number of subsidiary flares to the lower left of the main "flash". These are presumably caused by different parts of the satellite catching the sun before the main solar array, which doesn’t happen with Iridium flares.For comparison, here’s a couple of shots of Iridium flares. The first one has an unusually bright centre section (actually mag -8 or brighter!) and the second is a quite rare double flare – it’s a single exposure of 30secs, capturing two adjacent flares just 6 sec apart.
Bizarrely, while I was composing this reply I popped outside to see whether the sky was clearing and, purely by chance, saw a flare low down in the west! This was not listed as an Iridium flare by Heavens-Above but IGS 1A was passing that exact spot at the right time so I assume that’s what it was. The IGS family is known to flare, which raises the possibility that the "event" I saw on 11th June was caused by IGS 5A rather than Terra: it had almost exactly the same track but was close to Arcturus 1min earlier (which is within the tolerance of my "quick look at my watch in the dark" timings).Further comments invited.Steve HolmesPosted by Peter Meadows at 21:43 on 2013 Jun 13
Steve,Here is an image of another Earth Observation satellite, Envisat, which shows flaring. The image was taken last August (5th at 21:16 UT). The Summer Triangle comprising Deneb (top left of image), Vega (middle) and Altair (bottom left) and some high thin cloud are also shown. Peter
Posted by Martin Mobberley at 20:04 on 2013 Jun 11
Nick,The basic answer to your question is YES. If you go to: http://www.minorplanetcenter.net/iau/Ephemerides/SoftwareEls.htmlyou will see a list of orbital elements which can be downloaded for use in various popular software packages…. My favourite is Guide (now at version 9.0). Every package has its own way of uploading NEO data, which will be covered in the manual. If all else fails orbital elements can be typed inmanually for a specific object by going to:http://www.minorplanetcenter.net/iau/MPEph/MPEph.htmland entering the object name plus selecting a format for elements output.HOWEVER, planetarium packages become inaccurate if the NEO is passing so close that the Earth’s gravity starts to dominate. In this case using that MPEph web page above is more accurate than a planetarium package if the object is, say, closer than the Earth-Moon distance. It is also important to specify your exact location on Earth as clearly the Earth’s radius of ~4,000 miles can cause a significant shift in apparent position if an object is within a few hundred thousand miles of us!If by ‘plot’ you also mean ‘plot a track’, then certainly Guide 9 can do that too, once the orbital elements are installed. But again, the observer’s location on Earth needs to be accurate and for very close NEOs the track may be inaccurate by a significant amount. For NEOs that are more than, say, half a million miles away the track should be accurate enough for all reasonable telescope slewing purposes…….Martin>Please advise if any planetarium software will give a plot of an NEO. Cheers Nick<
Posted by Martin Mobberley at 11:49 on 2013 Jun 09
I agree 100% with all that Nick has said in his post. The ‘Whizz-Bang’ flashy graphics content of modern science programmes annoys me intensely too. In many cases it seems mandatory to install ‘celebrity’ presenters to simply boost the ratings and in others the science content is so dumbed down to be inaccurate. Then there is this constant obsession with nauseating background music. I presume this musical requirement is drummed into all graduates of media studies courses just as hard as grinning insanely is drummed into North Koreans whenever a picture of Kim Jong-un is displayed?!As Nick has said, the Horizon programmes of the 1980s were a model of how to get it right. The voice of Paul Vaughan was perfect but he never appeared ‘on camera’, ensuring that the programme was about the topic and not simply a battle between rival presenters as to who can get more camera time, crack more jokes and look more insanely happy! When Bill Oddie, Kate Humble and Simon King presented Springwatch and Autumnwatch I could enjoy those programmes, but not anymore. There comes a point in modern TV where the presenters grab so much camera time that the subject matter disappears entirely. Personally, I would say that apart from David Attenborough’s programmes (surely the only presenter in Patrick’s league still surviving) the only TV Physics presenter I can comfortably watch is Jim Al-Khalili. I thought his series ‘Atom’ on BBC4 a few years ago was excellent. A lot of the BBC Natural History programmes are also excellent, at least where they have a high quality narrator, whose voice alone features in the programme, so there is no distraction caused by the attention seeking of a token ‘celebrity’ presenter.As far as The Sky at Night is concerned, well, I can never feel the same way about it since Patrick’s demise and everyone I know feels the same way. I still record it and occasionally skim through the recording, but it can never be the same show without Patrick. For more than 40 years I was an avid watcher, but things can never, ever be the same, despite the hard work of the current presenters.I might shamelessly add, that having researched and written a 330,000 word biography about Patrick, occupying much of my time over the past eleven years [out in August!] I am perhaps more familiar than most with the earliest years of The Sky at Night and Patrick’s desire to keep it a simple and low cost affair…… End of blatant book plug!Martin
Posted by Nick James at 19:53 on 2013 Jun 08
At the risk of sounding terribly old, I don’t watch much science on TV any more since the content and presentation annoy me so much. I understand why programme makers target a large proportion of their output at a general audience and we all benefit through encouragement of an interest in science and astronomy, but I would hope for the odd "heavier" programme.I have a recording of a 1985 Horizon, narrated by Paul Vaughan, which covers the Grand Unification of forces. To me it it is model of how to explain a difficult concept, clearly and without hype. Modern Horizons don’t do that for me but I suppose that the 1985 version would probably send 95% of a modern audience to sleep…The Sky at Night certainly used to be a programme I watched every month. Things are very different now and I rarely get to watch. That’s not to say that it is in some way "worse" than before, but it seems that the programme is targetted at a different audience. For me, the Internet has replaced TV, and I find most of what I want there.Nick.
Posted by D A Dunn at 17:48 on 2013 Jun 08
David,Don’t get me wrong. I liked the old format too. Having watched the programme since 1965, I learned lots about Astronomy from watching. I also tried to get my children to watch when they were younger. Now I guess I will have to work on my grandchildren.I also like the "talk by the expert" slot, and I guess this is the big weakness with the new format.As, I guess, the new team are BAA members, then perhaps they might take note of intelligent(?) views on the subject.Oh well after some clear nights, I’m back to processing images.David
Posted by David Basey at 09:13 on 2013 Jun 08
D A Dunn wrote:
If it is below the level of BAA members then I am not surprised but perhaps it has always been so. Maybe it was only Patrick’s magic that made us believe otherwise.David,I think the point I was making was that the old format did have something for everyone, not just the ‘man on the Clapham omnibus’ but BAA members also (well myself anyway).When I started out in astronomy as a teenager my total knowledge was what I had gleaned from the Observer’s book of Astronomy, there were constellations, Saturn had rings, Jupiter a Great Red Spot that sort of thing. Clearly the Sky at Night taught me a lot but even forty years on it remained relevant. I believe it is a question of breadth and depth. Most BAA members will have a broad knowledge of the whole spectrum of astronomy, enough to talk knowledgably to the man from Clapham. Some will also have a very deep understanding of a narrow topic. So a specialist in comets may well only have a superficial knowledge of lunar geology. With this in mind a programme on that subject that goes into some depth potentially will add to a lot of members understanding.Patrick’s ‘magic’ if you like was to present a subject in a way that gave something to both the teenager starting out and the old hand by starting with the basics and building from there a deeper picture.Now clearly the old format of a lengthy interview with a studio guest by a gifted presenter lends it self well to achieving this. Of course that is not to say that the new format can’t do the same but I would contend that, at the moment, it is missing that particular mark. I guess the previous format is no longer considered relevant or entertaining enough for today’s audience.Ultimately however we have to take the bigger picture and if for every old fart like me the programme alienates it brings another new person into the hobby then it is a price worth paying.Mind you, it doesn’t stop me being saddened by what has happened to the Sky at Night!David
Posted by D A Dunn at 22:19 on 2013 Jun 07
Well, I’m not sure I agree. While the music is somewhat aggravating, it wasn’t as bad as some of today’s programmes.As to content: I would not expect a BAA member to learn much from any sky at night programme. We have many other sources for detailed specialist information. However for the man on the Clapham omnibus I feel that this programme still hits the mark. Obviously Sir Patrick was unique and cannot be replaced but the new team, I feel, makes a good fist of putting across the subject matter in a clear and friendly manner.If it is below the level of BAA members then I am not surprised but perhaps it has always been so. Maybe it was only Patrick’s magic that made us believe otherwise.David
Posted by David Basey at 10:45 on 2013 Jun 07
Paul,I agree 100%For the last 40 years I’ve looked forward to the monthly Sky At Night broadcast, but now frankly it would not bother me if it was cancelled. I’m not quite at the point of turning off but there are certainly segments I fast forward through.It seems to me that it has been dumbed down. My wife who was (unusually) watching it last night turned to me and asked "Is this being aimed at children now?"Certainly the production values do not seem to be what they were and it is very sad and somehow disrespectful of what Sir Patrick built up over the years.
Posted by Nick Atkinson at 19:25 on 2013 Jun 05
Please advise if anybody knows if you can import the orbital elements into the SKY X from M.P.C. either by a download or manual import?I have already competed a time series of this Asteroid.
Posted by Steve Holmes2 at 11:20 on 2013 Jun 02
Hmmm – seems like a job for the Director of the Asteroids & Minor Planets Section. Now I wonder who that might be??
Posted by Richard Miles at 09:43 on 2013 Jun 02
Just one of those coincidences like you say Steve – But, I wonder, will anyone bring it to the attention of the Royal Family?
Posted by Steve Holmes2 at 23:17 on 2013 Jun 01
Here’s a couple of images I took around the date of closest approach, plus one a bit later. The first two have Jupiter to the left, Venus to the right and Mercury on top. The first is on 26th May, the second is on 27th May – showing how fast Mercury and Venus move. The third one is on 31st May, with all three in a straight line (Mercury-Venus-Jupiter). In case you can’t find it, Jupiter is hiding in the very lowest patch of pink sky! (you’ll probably have to click on the image to see it)All images are to the same scale and were taken from precisely the same location, by the way.
Posted by Gary Poyner at 13:36 on 2013 May 27
Just had a look at the interactive Comet charts. Excellent – and thank you for including B-V measures. Saves a lot of work this end. Well done the computing team!Gary
Posted by A R Pratt at 17:51 on 2013 May 22
Hi John,’The Astronomer’ (TA) is a popular magazine for observers to publish and share their latest observations and images, but as TA will confirm, formal reports of variable stars, comets and occultations, etc should also be submitted to the Observing Sections of the BAA or other coordinating body.Tim can help you with your occultation work.Clear skies, Alex.
Posted by Tim Haymes at 22:25 on 2013 May 21
Hi John,Pleased your screen display works now. I would like to tempt you further with Asteroid Occultations.UK observers have made a significant number of observations over the years (1997-2013). Ive looking through the Euraster.net results pages where the data is logged. If you made your observation in this time period, it does not appear to have reached its correct destination.If you have the observation for your positive asteroid event, I could arrange to have it submitted? Thanks in advance.Regards, Tim
