Guest Posted December 11, 2017 Share Posted December 11, 2017 Got one at last!!! Link to comment Share on other sites More sharing options...
Orion Posted December 13, 2017 Share Posted December 13, 2017 Got one, in a different way, by radio. Big event at 03:58am, 13 Dec 2017. I didn't see it visually (cloudy, and may not have been in my location even if it was clear) Link to comment Share on other sites More sharing options...
Doc Posted December 13, 2017 Share Posted December 13, 2017 Derek looking at the time this lasted about 30 seconds is this correct. If so it must have been a pretty big one. Link to comment Share on other sites More sharing options...
Orion Posted December 13, 2017 Share Posted December 13, 2017 Hi Mick. Yes, the time scale is correct and the length of duration is about 30 seconds. I'm not sure whether that would equate with the visible duration (expected to be over in a second or two). It's more likely to represent the duration of the ionised plasma generated. Sometimes the ion trail is left after the fast streak has gone, but some can be seen as "smoke trails" that appear to drift like clouds. A long exposure on a camera can pick them up but can't be seen by eye; perhaps a bit like how the long exposures of faint aurorae not visible to the naked eye, can be picked up on long exposure. I think the radio detects the ionised plasma because it can reflect radio waves (or so I'm told). I don't know the physics of how ionised air can reflect radio waves and non ionised air can't. Hmm, I need to know now. I'm guessing; charged particles possibly have a dipole or some charge separation where electromagnetic radiation can interact. Link to comment Share on other sites More sharing options...
Doc Posted December 13, 2017 Share Posted December 13, 2017 I was thinking the same Derek. As you say the visible part of a meteor is over in seconds normally, does the radio detect the meteor as soon as it enters the atmosphere and starts burning up? Link to comment Share on other sites More sharing options...
Orion Posted December 13, 2017 Share Posted December 13, 2017 I don't really know how and when the radio detects the meteor Mick. I'm thinking along the same way as your thoughts. But I know that planes and the ISS can be detected and show up on real time plots as bending slotted/dashed lines. Those aren't ionised, so solid bodies must also reflect radio waves like in the way it is used to detect things with RADAR. I would think that the meteor may be detected before ionisation, then as it ionises, a plume of plasma develops, which also reflects the radio waves. It is a good point you raised because the shapes of the radio meteor plots are varied in shape and intensity. Sometimes the trails split into two and continue, which might indicate break up into fragments. The trace seen, expands from a sharp peak to a one that extends in time axis (for the duration) and also in the Y axis which is frequency in Hz, which gives some idea of the doppler shift of the signal. I don't know what that means with respect to the meteor, but I understand about red and blue shifted frequencies due to the body also moving away or towards the detector. I think I'm going to have to add to my list of astro learning, how meteor radio detection works. I have a pile of imaging books to read as well. Link to comment Share on other sites More sharing options...
Doc Posted December 13, 2017 Share Posted December 13, 2017 Well what ever the reason you are doing a grand job and I always enjoy reading about it, even though I don't fully understand it Orion 1 Link to comment Share on other sites More sharing options...
Orion Posted December 13, 2017 Share Posted December 13, 2017 Thanks Mick, it's a great complement when I hear things like that. Link to comment Share on other sites More sharing options...
Guest Posted December 13, 2017 Share Posted December 13, 2017 Hi Orion, it is hissing down here, just at the peak of the shower. I think your radio detection is a better idea. Link to comment Share on other sites More sharing options...
Orion Posted December 13, 2017 Share Posted December 13, 2017 Clear here, but windy. I'm going to set up my camera and run it from inside the house. Link to comment Share on other sites More sharing options...
Guest Posted December 19, 2017 Share Posted December 19, 2017 For now I'm imaging at 70mm, as my 18-55mm lens is kaput! Maybe lucky but, by the law of averages I will catch a few simply by the sheer number of frames I take. TBH, it looks better sized smaller. Link to comment Share on other sites More sharing options...
Orion Posted December 19, 2017 Share Posted December 19, 2017 9 minutes ago, Sunny Phil said: For now I'm imaging at 70mm, as my 18-55mm lens is kaput! Maybe lucky but, by the law of averages I will catch a few simply by the sheer number of frames I take. TBH, it looks better sized smaller. I think if you're taking lots of images, you will increase the chance of catching meteors. I read someone used higher focal lengths because he got more detail than those obtained from the wider field lenses, even though his chances might be less. The image above suggests the focus is out a bit, but it's better than missing that meteor. But it's easy to happen because the chances of focus altering also increase with the longer period of time. I've had to refocus during the night. Link to comment Share on other sites More sharing options...
Guest Posted December 20, 2017 Share Posted December 20, 2017 8 hours ago, Orion said: I think if you're taking lots of images, you will increase the chance of catching meteors. I read someone used higher focal lengths because he got more detail than those obtained from the wider field lenses, even though his chances might be less. The image above suggests the focus is out a bit, but it's better than missing that meteor. But it's easy to happen because the chances of focus altering also increase with the longer period of time. I've had to refocus during the night. If focus is slightly out, it is emphasised when an image is "blown up". I've started cropping images so that the meteor trail is easier to see. I think my colour balance isn't great here but it doesn't look so bad when the image is viewed at normal size. Link to comment Share on other sites More sharing options...
Guest Posted December 20, 2017 Share Posted December 20, 2017 Another one. Link to comment Share on other sites More sharing options...
Orion Posted December 20, 2017 Share Posted December 20, 2017 5 hours ago, Sunny Phil said: Another one. I like this one with all that colour. I forgot it was cropped, which obviously magnifies things in the enlargement. I sometimes find inverting an image and playing around with gamma and contrast can help bring out faint things. I've started to explore use of inverting, optimising on gamma and contrast, then for each one of the three colours (trying separately), I increase or decrease R, G, B currently in Irfanview, sometimes that can bring out faint comets. Link to comment Share on other sites More sharing options...
newtyng5 Posted December 25, 2017 Share Posted December 25, 2017 (edited) https://www.facebook.com/photo.php?fbid=10215944007019391&set=pcb.10215944052180520&type=3&theater Geminid from Lanzarotee, some clubbers were interested looked over and knocked my phone, and that was the image that captured one. (we saw about 60 in 2hrs). At least they watched with us for a few mins > suprising really. https://www.facebook.com/photo.php?fbid=10215944009059442&set=pcb.10215944052180520&type=3&theater Orion on it's side and almost overhead (not sure if these links work) Edited December 25, 2017 by newtyng5 Link to comment Share on other sites More sharing options...
Guest Posted December 25, 2017 Share Posted December 25, 2017 3 minutes ago, newtyng5 said: https://www.facebook.com/photo.php?fbid=10215944007019391&set=pcb.10215944052180520&type=3&theater Sorry, Rob, I cannot access it. Please send me a friend request. Link to comment Share on other sites More sharing options...
Tweedledee Posted December 25, 2017 Share Posted December 25, 2017 I don't do facebook Rob. Could you put it up again in the usual way please? newtyng5 1 Link to comment Share on other sites More sharing options...
newtyng5 Posted December 29, 2017 Share Posted December 29, 2017 Hi. Sorry, had probs getting the pics off my phone. Will edit and repost. Link to comment Share on other sites More sharing options...
newtyng5 Posted December 29, 2017 Share Posted December 29, 2017 Cannot seem to edit the old post, anyway here we go. Orion 1 Link to comment Share on other sites More sharing options...
Orion Posted January 5, 2018 Share Posted January 5, 2018 On 12/29/2017 at 18:36, newtyng5 said: Cannot seem to edit the old post, anyway here we go. The post date was 29 Dec but what was the observation time and date? Link to comment Share on other sites More sharing options...
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