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kirkster501

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Everything posted by kirkster501

  1. Yes I am noticing the Geostationaries as well.
  2. Ahh, is it? I thought it was an emission nebula excited by Rigel? That may be the reason then.
  3. I am doing RGBHa on it Stuart, not OSC. I'm not at that machine at the moment so will share later but hardly anything there. Maybe due to its quite low altitude - unlike the Heart that can be overhead - it needs better seeing and conditions (and zero moon).
  4. ...or is it me, perhaps doing something wrong? Certainly the moon does not help. I captured 18 x 10min exposures in Ha the other night through the Astrodon 3nm filter when the Moon was about 70 degrees away. There is almost nothing to show for that time. Last night before the moon came up I grabbed about three hours of RGB 1x1. Again, yes I can discern the Witch Head but there is not a lot to show. How does this object rank in terms of bang for the buck (aka time spent on it) please? Thanks Steve
  5. Many of the HST sensor's iconic images have been taken with small sensors by today's standards. Consider the last servicing mission was in 2009 - a lifetime ago in electronics terms. In many cases all this sensor megapixel stuff is consumer marketing.
  6. Agreed, as evidenced by the fact that the sensors, by today's (2022) standards, are quite small. There would have been a change freeze long ago.
  7. The start of 2022 isn't so bad so far. Two clear nights in the first week and three this week although the moon spoils this week a bit for DSO.
  8. This has to be the most complex project humanity has ever attempted. Not the most important - of course not - but the most complex. It is almost unfathomable the amount of pioneering technology that exists inside the JWST. To say nothing of actually building it, transporting it, launching it and getting it on the correct trajectory. The Apollo program was a piece of cake compared to this!
  9. Thanks Dave, will take a look mate. Cheers, Steve
  10. Hi guys, I want to do this power modification from this old thread and need a /shallow/ socket for the NEQ6. Does anyone have any UK suggestions please? Microsoft Word - EQ6 Power Plug Modification (bendun.net) Thanks, Steve
  11. Yes, assuming they *can* steer it Keith. What if one mirror is a complete (or becomes a complete) duffer over the lifetime of the mission so that its movement is impeded or stops working completely? There must be ways whereby they can subtract that mirror's input to the composite optical image, maybe electronically.
  12. Remember the collimation of even one segment will be orders of magnitude better than what we can do with our 12" Dobs. But furthermore, they have to do that with respect to each other as well. Each mirror must match the others with incredible accuracy. How would they see the airy disk???? It is beyond incredible!
  13. They still need very long exposures though. If you take a 30 minute exposure to image extremely distant objects in the depths of the early universe, even the orbit of the telescope around the sun during that 30 minutes will blur the image. The imaging sensor has to be moved very slightly with either the entire telescope or the fine guiding mirror to compensate for that orbital motion and the amount of movement is dependent on where in the sky it is imaging. The more you think about it the more amazing this telescope and its engineering becomes.
  14. There are still a lot of moving parts to getting this thing deployed yet, despite the success so far. The mirrors themselves have to be "unlocked" (they were locked to prevent the launch vibrations wrecking them). The unlocking moves the mirrors - the entire mirror segment - forward by about one cm. Do that 18 times. But then, amazingly, they can be moved to nanometer precision with respect to each other. How can any motor have the granularity to do that? As an engineer myself I find that fascinating. Even a motor focus that many of us use on our home telescopes can move the focuser to micron accuracy. But to nanometer accuracy, in those extreme cold temperatures after surviving the stresses of launch? It is quite incredible. You can see why this thing cost $10billion.
  15. I think they are going to commence with the mirror positioning today now that the shaded side has dropped low enough in temperature.
  16. NASA's James Webb Space Telescope’s albums | Flickr Great series of albums with pictures of the JWST at various stages of its development. On another note I thought they'd be broadcasting the main mirror wing unfolding but seems that is not happening today. Hopefully NASA are not having a POETS day ( I am sure you know what that stands for 😂)) .
  17. Webb’s Specialized Heat Radiator Deployed Successfully – James Webb Space Telescope (nasa.gov) Radiator opened successfully. "Just" the mirror flaps now.
  18. There is a movable steering mirror inside the black nose thingy that sticks out from the centre of the primary. That can be "steered" (i.e moved) so the telescope does not have to physically move so much. Just image how accurately that must have been ground and polished ! Yes, for subjects on the "wrong" side of the sky the JWST has to wait just like we have to for them to become visible in the night sky again.
  19. We live in a Facetime/Teams/Zoom society where webcam/video is seen as second nature (more so since the pandemic started(). However, the cold side of Webb is as black as night - literally. How would that be lit so that a potential "camera" could see what was going on? How would a camerra operate at -200C? What about the wiring and software for these cameras? How many such cameras? True, the IR instruments themselves operate at that temperature, but they cost hundreds of millions to build. They weighed the camera idea up and in the end decided they could achieve what they needed to without them by instrumentation.
  20. I read it on one of the technical articles on University of Arizona website last year and shared on the thread. Something to do with the wavelength of the IR light and a certain amount of mirror area they need in order to gather enough light for the IR instruments or else they will not work properly. Remember JWST is an IR telescope operating at much longer wavelengths than the HST. The resolution of the images that Webb will produce (even with both mirror wings properly deployed) will not be any higher than the HST because Webb is operating in the IR and so needs a correspondingly larger mirror for the same resolution as the HST does in visible light. This is why LUVOIR, operating in the visible light spectrum, BUT with a huge mirror 15m across will be truly outstanding if it is ever built. That huge mirror and visible light wavelengths!
  21. Amazing , it deployed! That was my biggest worry about the whole deployment.
  22. I was observing from 18.00 to midnight and at the same time captured data from 17.00 yesterday until 06.30 this morning. Over 13 hours worth. That’s the best clear night I have ever had in the UK in 18 years of practical astronomy.
  23. Me too. This is mission critical - nuclear level. Even if the sunshield didn’t work, there was still a mission of sorts. No secondary and, as well all know, JWST is a piece of space junk. It is broadcast on NASA live later.
  24. Layer 4 just been tensioned. They are on the final layer now.
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