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Featured B Space Stuff and Launch Info

  1. Sep 14, 2017 #361
    Wow! a great collection, thanks for posting that. The entertainment value certainly wasn't lacking. (Love that line "Entropy... is such a lonely word")
     
  2. Sep 15, 2017 #362

    Borg

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    I'm not sure if it's been posted before but I saw this while listening to the final Cassini mission this morning. Looks interesting if I ever find the time.

    NASA’s Eyes
     
  3. Sep 15, 2017 #363

    mfb

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    Cassini's mission ends in 10 minutes

    Actually, that is the end of received transmission, so it is probably getting destroyed right now.
     
  4. Sep 15, 2017 #364
    on that topic, how hard is it to park it on a small moon(asteroid), im not familiar with its orbit.?
     
  5. Sep 16, 2017 #365

    mfb

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    There are no small moons nearby that could have been reached with the fuel, and "parking" would still mean impacting it.
     
  6. Sep 16, 2017 #366

    OmCheeto

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    I've been using it since at least March of this year.

    I've used it to monitor the flight path of the Dawn mission, the Cassini mission, and preparing for the eclipse last month.

    My younger brother emailed me two days ago, and asked if I was going to set up my telescope to watch Cassini vaporize.
    I was able to determine that Saturn was going to be below the horizon during the "vaporization" phase, so I didn't bother.

    One of the best pieces of software around, IMHO, and I highly recommend it.
     
  7. Sep 16, 2017 #367

    mfb

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    Oh, that was the problem, not the multi-kilometer-sized telescope you would need to watch it?

    Yet another company is working on reusable rockets. Apparently they did hover tests already, similar to the Grasshopper SpaceX used. 15 to 30 million CNY are 2.3 to 4.6 million USD, comparable to the Electron rocket (not reusable) with the same payload range (about 150-200 kg) for $5 million.
     
  8. Sep 16, 2017 #368

    OmCheeto

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    Well, given that I could barely make out Saturn with my new/old telescope, I hadn't really given it a thought until he mentioned it.
    Had I had more time, I'd have tried and figured out if Hubble could have witnessed the "blink".
    And I couldn't remember if Hubble was the one to capture Shoemaker-Levy 9 making a splash into Jupiter, (looks like it did: ref) so, I didn't bother calling NASA.
     
  9. Sep 16, 2017 #369

    davenn

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    ohhhh I remember that .... I saw the big black impact points soon after they occurred through my then 8" Newtonian scope back on New Zealand
    seems a lifetime ago LOL


    Dave
     
  10. Sep 17, 2017 #370

    Borg

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    I was able to see the same with mine also. Pretty exciting to see something like that from my backyard.
     
  11. Sep 17, 2017 #371
  12. Sep 17, 2017 #372

    mfb

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    The Cassini impact had an energy of ~150 tonnes TNT equivalent;
    The largest Shoemaker-Levy 9 fragment had an impact energy of 6000000000000 tonnes TNT equivalent (6*1012), the total energy was even higher.
     
  13. Sep 17, 2017 #373

    davenn

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    kinda puts things into perspective, aye


    D
     
  14. Sep 18, 2017 #374
    Interesting alignments and occultations these days (Sept. 18-20):
    [I quote directly from spaceweather.com, for better accuracy of the complete story]

    "PLANETS FOR BREAKFAST:
    Are you awake before sunrise? Look east! Three planets have lined up in the pre-dawn sky--and the crescent Moon is gliding among them. This morning in Malaysia, Shahrin Ahmad photographed Venus just a fraction of a degree from the lunar disk:

    moonvenus_strip.jpg

    About 20 minutes later, the Moon completely covered Venus. "I almost saw it," says Ahmad, "but the clouds came in just as the occultation began." Later today, the Moon will pass Mars and Mercury as well, producing three lunar occultations in a single day.

    Tomorrow offers something new: Venus approaches Regulus, a bright blue star in the constellation Leo. The two will pass less than 1 degree apart on Sept. 19th and 20th forming a bright "double star" in the morning sky. Set your alarm for dawn and enjoy the show! Sky maps: Sept.18, 19, 20."
     
  15. Sep 18, 2017 #375
    Neat!

    By coincidence, I have just this morning been searching for calculators to generate an ephemeris for night sky visibility of the planets from my location; so far this site looks the most immediately useful: https://www.calsky.com

    However there is a fair bit of learning involved just to understand the charts, let alone how they are produced; so I have to buckle down.
     
  16. Sep 18, 2017 #376

    OmCheeto

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    I spent most of yesterday, and much of this morning trying to analyze this.
    My conclusion was that Hubble might have spotted the "blink". (≈10% chance)

    ps. Talk about a maths problem from hell.........
    pps. This assumes of course, that I interpreted everything* correctly, which I have a confidence level of about zero, so my conclusion may be off by a factor of "A LOT!".
    ppps. I think my "always suspicious maths" was spot on, but there are so many unknown variables, that I would advise everyone to just ignore this post.


    *:
    1. Light gathering power: Hubble is apparently 120,000 times better than we are (7mm vs 2.4 m) [ref: googled it]
    2. Hubble faint object camera: Can amplify light by 100,000. [ref]
    Multiplied together, gives 12 billion, which was at least 1 order of magnitude too small to see "the blink". (this was best case.)​
    3. Another bazzilion assumptions.
     
  17. Sep 18, 2017 #377
    Last edited: Sep 18, 2017
  18. Sep 18, 2017 #378
  19. Sep 19, 2017 #379

    mfb

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    Saturn is not a faint object. Even if the camera would still be flying (it was removed in 2002): If you point that thing on Saturn at best you overexpose everything, at worst you damage the equipment. Even a 21st magnitude object saturates the system.

    Saturn receives 36,000,000 tonnes TNT equivalent in sunlight every second, and the disintegration of the probe took minutes.
     
  20. Sep 20, 2017 #380
    Hubble has imaged an Asteroid with a personality disorder. http://hubblesite.org/news_release/news/2017-32
    "NASA’s Hubble Space Telescope helped an international team of astronomers find that an unusual object in the asteroid belt is, in fact, two asteroids orbiting each other that have comet-like features. These include a bright halo of material, called a coma, and a long tail of dust."
     
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