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Pluto Probe Snaps Jupiter Pictures

Posted by CowboyNeal on from the eye-in-the-sky dept.

sighted writes "The New Horizons probe, on its way to Pluto and beyond, is now speeding toward Jupiter. Today the team released some of the early data and pictures, which are the first close-range shots of the giant planet since the robotic Cassini spacecraft passed that way in 2001."

7 of 133 comments (clear)

  1. Re:How long does this take? by rumith · · Score: 5, Informative

    10 hours from Pluto in average. 45 minutes from Jupiter in average. Don't know whether they'll in their aphelion or perihelion now, so can't say more precisely.

  2. well this is where they are by rucs_hack · · Score: 5, Informative

    their exact position today can be found in the JPL Horizons database
    http://ssd.jpl.nasa.gov/horizons.cgi

    so using Sol as Origin [0,0,0], with distance in km and km/s velocity measures:
    XYZ position and velocity in Km and Km/sec
    V prefix = velocity,

    Jupiter
    A.D. 2007-Jan-19 00:00:00.0000 (CT)
      X =-3.523007925524937E+08 Y =-7.203651223053448E+08 Z = 1.087397270750013E+07
      VX= 1.158611696091788E+01 VY=-5.127849980674650E+00 VZ=-2.378734986696975E-01

    Earth
      A.D. 2007-Jan-19 00:00:00.0000 (CT)
      X =-7.005151113800500E+07 Y = 1.294518808525130E+08 Z =-1.647040773451328E+03
      VX=-2.669513206382950E+01 VY=-1.429493892074527E+01 VZ=-5.052885705412180E-04

    And the Horizons probe itself is here:
    A.D. 2007-Jan-19 00:00:00.0000 (CT)
      X =-3.141011231236297E+08 Y =-6.673772181265557E+08 Z = 9.200702373118341E+06
      VX= 1.154291925552546E-01 VY=-1.978644188955009E+01 VZ= 1.493924692614632E-01

    However it's too early to work out the times taken for signals to travel based on these positions. I need more coffee.

    1. Re:well this is where they are by KiloByte · · Score: 5, Informative

      Pythagoras' theorem says the distance in R3 (ie, euclidean space) is sqrt((x1-x2)^2+(y1-y2)^2+(z1-z2)^2).
      That is, the distance between Earth and Jupiter right now is: 8.95528824E8 km.

      Dividing that by c gives 2987 seconds. So, right now the half-ping is 50 minutes.

      By similar calculation, you can get that EarthNew Horizons is 2779.975 s =~ 46 minutes.

      --
      The creatures outside looked from Alt-Right to Antifa; but already it was impossible to say which was which.
    2. Re:well this is where they are by FallOfDay · · Score: 5, Informative

      The rough & ready, easy-on-the-eye (!), pictorial version is as follows:
      http://pluto.jhuapl.edu/mission/whereis_nh.php

  3. +2 Interesting!? Mod Parent Down by physicsnick · · Score: 5, Informative

    it takes 8 minutes to send a signal as far as mars and 4 years to send one to Alpha Centuri, which Voyager 1 is predicted to reach in later 2009.

    Voyager 1 will take on the order of several hundred thousand years to reach Alpha Centauri.

    The traditional explanation for this is that the graviton can only travel at the speed of light and as such will take 10 minutes to travel from one particle to the other, so far so good.

    The 'traditional' explanation? Gravitons are hypothetical at best, and currently mathematically useless. Quantized force mediators do not need to "intercept" a moving particle at a distance; they are virtual, and there are infinitely many of them in all directions.

    By changing the mass of the ball (simple enough to do with a powerful laser)

    This is all nonsense. Even if this were true, your probe is also receiving gravitons from every other atom in the universe. The effect of varying a "ball of mass" would not even be measurable. Just because a sizable block of text with "sciency words" is posted doesn't mean it's meaningful, and certainly doesn't deserve mod points. Please mod parent down, and please read things before giving points!

  4. Re:How long does this take? by Tom+Womack · · Score: 5, Informative

    http://pluto.jhuapl.edu/science/data_collection.ht ml says that the transmission is at 38kbit/second from Jupiter, and will be at around 450bit/second from Pluto.

    Cassini runs at 82kbit/second from Saturn, but it's a probe with a larger power budget.

    The imager takes one-megapixel, 16bpp images, and compresses them to 100kbyte files for initial transmission, saving the originals in a few gigabytes of onboard flash; it can be instructed to send back uncompressed images if there's something interesting visible.

    So an image takes about 20 seconds to transmit, plus about six minutes if you want the uncompressed version; and it takes 45 minutes to get to Earth from Jupiter. From Pluto, the images will take half an hour for the preview and twelve hours for the uncompressed image.

  5. Re:How long does this take? by gsslay · · Score: 5, Funny

    Unfortunately it then zips the compressed image into a self-extracting exe, so NASA's anti-virus strips it off at the mail server.