back to article Dawn spacecraft to get up-close and personal with dwarf planet Ceres

The Dawn spacecraft orbiting dwarf planet Ceres will soon make its final course change as NASA boffins set it up for a closest-ever flyby yet to get a warts-and-all look. Ceres is the largest body in the Asteroid Belt and orbits between Mars and Jupiter. Dawn's been there since 2015, mapping the surface from hundreds of miles …

  1. RyokuMas Silver badge

    "Ceres, which was originally classified as a planet after its discovery in 1801 but then relegated 40 years later..."

    "That's no planet..."

    1. MyffyW Silver badge

      "aren't you a little short for a planetoid?"

      1. TechnicalBen Silver badge


        We can promote it to the 9th planet... just to REALLY mess things up. ;)

        1. HelpfulJohn

          Re: Optionally

          " ... We can promote it to the 9th planet... just to REALLY mess things up. ;) "

          Counting Earth's Luna as the fourth, Ceres would be the Fifth World. That would make Pluto "Planet Ten", or "Planet X" for at least two different reasons.

          Yes, I know both Ceres and Pluto have little sisters but we can conveniently ignore those as " and assorted detritus" just to keep the joke going.

          No one ever said Science had to be entirely humourless.

  2. IanTP

    That's no moon....

    Sorry, I'll get me coat.

    Beer later :)

  3. Michael Habel Silver badge

    No Moon?

    So is this Kathleen Kennedy's summer home?

  4. Spiracle

    Point of Order

    Isn't it Mimas that's the Death Star look-alike?

    1. Aladdin Sane Silver badge

      Re: Point of Order

      That's no Death Star.


  5. DougS Silver badge

    Infect it with terrestrial trash?

    Why do they care, given that we know it wouldn't support life? We didn't have any problems with trashing up the Moon, Mars, Venus and Titan, why is Ceres getting the Greenpeace treatment?

    1. Mike Richards

      Re: Infect it with terrestrial trash?

      Probes to Mars and Titan are sterilised before launch (although the Soviets may not have done so with some of their early Mars probes). The type of sterilisation depends on the mission, but are formally known as COSPAR Category III and Category IV. Mars missions are further categorised depending on whether or not they are searching for life.

      Dawn was classified as Category III requiring a ultra-high cleanroom. In part this category was due to the probe making a Mars flyby and there being a non-zero chance of it splashing onto Mars; but also because Ceres had previously been identified as a site where there may be evidence of life or its precursor molecules.

      Probes to the Moon and Venus only need a lower Category II certification since neither is thought to be capable of supporting life as we know it. Category II requires the mission planners to inform the world of where the probe is going and the impact of it - well impacting - such as if it contains toxic materials or radioisotopes that could be hazardous in the future.

      There is also a Category V which is reserved for sample-return missions; again this is subdivided into whether probes are going to potentially life-bearing destinations.

      And finally, Category I is for missions going to places where there is no possibility of finding life or its precursors - such as solar probes.

      1. Anonymous Coward
        Anonymous Coward

        Re: Infect it with terrestrial trash?

        <no possibility of finding life or its precursors - such as solar probes

        I'm sure that there's a White House anal probe joke here, but I'm not going to make it.

  6. onefang Silver badge

    I wonder how far out the Death Star's, er I mean Cere's shield generator operates at?

  7. DropBear Silver badge

    "NASA has since discovered a 13,000 foot-high ice volcano on the surface"

    ...but how much is that in Proper Science Units aka metres?!? Kernel panic: 13000 isn't divisible by three...!

    1. John McCallum


      13000 = 3.9624 Km

      1. onefang Silver badge

        Re: Height

        Yes, but what is it in Proper El Reg Units?

        1. Aladdin Sane Silver badge

          Re: Height

          28303.9408 Linguine, 429.8245 Double-decker bus, 180.2799 Brontosaurus.

        2. Kevoc

          Re: Height

          That would be 26,000 pints high. Give or take. In standard pint glasses.

      2. Zwuramunga

        Re: Height

        "About Four Kilometers."

  8. 89724102371719511892724I9755670349743096734346773478647852349863592355648544996313855148583659264921

    Icy water jets from Uranus are worrying to all but zombies

  9. HelpfulJohn

    "... ten times closer ..."?

    How many smallness units are in the original orbit? Twelve micro-bananas?

    Yes, I also hate "five times colder" and "sixty times darker".

    Ceres is (at a very poor guess) 164 million miles from here (at that range, "here" is approximately the entire Earth, possibly including some of Texas). Dawn is 164 million miles closer to Ceres than Earth is. Or more, depending on where each world is in its orbit.

    To be "ten times closer", Dawn would need to be one thousand, six hundred and forty million miles closer to Ceres than Earth is.

    That makes no damned sense at all.

    And it's a lot on the banana scale of measurement.

    Why not use the perfectly sensible "... one tenth as far from ..." or something similar?

    [The Alien because I never really understood how one could see 2C as five times colder than 10C.]

    1. Richard 12 Silver badge

      Re: "... ten times closer ..."?

      1/10 the distance, 1/5 the temperature (or 1/5 the heat, they're different), 1/60 the brightness.

      Probably. Could also mean reducing the distance by ten times the amount they previously reduced it.

      I hate that kind of phrasing too, as there's many ways to misinterpret it.

  10. Anonymous Coward
    Anonymous Coward

    Accuracy of the models

    Let's hope that the models are accurate so the probe is not lost. But 45,000 simulations is impressive.

  11. Nano nano

    Cliched phrase

    Why is "up close and personal" even a phrase, apart from there having been a film of that name ...?

  12. ravenviz

    potentially infect the asteroid with terrestrial trash

    Sshhh, no one tell Philae it’s terrestrial trash.

    1. onefang Silver badge

      "Sshhh, no one tell Philae it’s terrestrial trash."

      It's OK, I don't think Philae can hear us, coz in space, no one can hear you trash talk.

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