Slashdot Mirror

← Back to Stories (view on slashdot.org)

Asteroid Apophis Just Got Bigger

Posted by samzenpus on from the a-little-chin-music dept.

astroengine writes "As the potentially hazardous asteroid makes closest approach to Earth today, astronomers using the European Herschel Space Observatory have announced something a little unsettling: asteroid 99942 Apophis is actually bigger than we thought. Herschel astronomers have deduced that Apophis is 1,066 feet (325 meters) wide. That's 20 percent larger than the previous estimate of 885 feet (270 meters). 'The 20 percent increase in diameter, from 270 to 325 m, translates into a 75 percent increase in our estimates of the asteroid's volume or mass,' said Thomas Müller of the Max Planck Institute for Extraterrestrial Physics in Garching, Germany, and lead scientist of the study. In addition, the space telescope has re-analyzed the albedo of the space rock, providing a valuable heat map of the object's surface — data that will improve orbital trajectory models."

25 of 182 comments (clear)

  1. So... by Anonymous Coward · · Score: 5, Interesting

    ...does this mean we're more likely to die or less likely to die?

    1. Re:So... by Anonymous Coward · · Score: 5, Insightful

      No, the chances we are all going to die are still 100%. The only question is when.

    2. Re:So... by TempestRose · · Score: 4, Funny

      Speak for yourself. I plan to live forever.

    3. Re:So... by Anonymous Coward · · Score: 5, Interesting

      Only about 95% of all humans who have ever existed have died. There's still a 5% fighting chance immortality exists. Not only that, but my odds are better than most humans, past and present.

  2. And Leon's getting LARGERRRR! by Anonymous Coward · · Score: 5, Funny

    Someone had to say it.

  3. Size Queen Weekly claims Aphophis 20% bigger by kawabago · · Score: 4, Funny

    Astronomers. My asteroid is bigger than your asteriod. Is not! Is too! Is not! Is too!.....I guess we'll both need grants for a few years to study the question.

  4. Apophis larger than we thought by egcagrac0 · · Score: 4, Funny

    Does this mean we need to prepare for a Goa'uld invasion?

    1. Re:Apophis larger than we thought by girlintraining · · Score: 4, Funny

      Does this mean we need to prepare for a Goa'uld invasion?

      No. Antarctica is melting at an unprecidented rate. It's only a matter of time before they discover the research station the Ancients left behind.

      --
      #fuckbeta #iamslashdot #dicemustdie
    2. Re:Apophis larger than we thought by cervesaebraciator · · Score: 5, Funny

      Shouldn't be too hard. So long as we can fund about three people, only two of whom actually need to be soldiers. If they can convince one of Apophis' guys to join our side, that should be enough to defeat the lot.

    3. Re:Apophis larger than we thought by a_hanso · · Score: 4, Funny

      No. It means it's made of Naquadah: http://stargate.wikia.com/wiki/Naquadah_asteroid

  5. SG-1 by madsci1016 · · Score: 4, Insightful

    SG-1 Will take care of it no doubt.

  6. 2029 approach by olsmeister · · Score: 5, Informative

    They're also saying that Apophis will pass within 36,000 km of Earth in 2029. Now that's not missing us by much.

    1. Re:2029 approach by SternisheFan · · Score: 5, Informative

      They're also saying that Apophis will pass within 36,000 km of Earth in 2029. Now that's not missing us by much.

      And that'll be about the right time for our space-tech to have caught up enough for us to be able to 'lasso' it. If we miss it then, by it's expected return in 2036 we'd better be able to control it. It seems to keep getting a little closer with each return orbit.

      From the above link:

      " The asteroid will return to Earth's neighbourhood again in 2036, but quite how close it will come then is uncertain, as the 2029 approach is predicted to alter its orbit substantially. Obtaining improved physical parameters for Apophis and its orbit is thus of great importance in being able to make better predictions of its future trajectory." Read more at:

    2. Re:2029 approach by Sowelu · · Score: 4, Informative

      For those who are hoping to see it, that distance puts it at two arcseconds wide (if my calculations are decent). This is roughly the same width in the sky as Neptune, or 900 times smaller diameter than our moon on an average day.

    3. Re:2029 approach by InterestingX · · Score: 4, Funny

      "Carter, I can see my house from here."

    4. Re:2029 approach by Daniel+Dvorkin · · Score: 5, Interesting

      It's a lot easier to calculate orbit than mass, and the latter is pretty much irrelevant to the former--Earth is so much more massive than Apophis can possibly be that the asteroid's mass can be ignored in any orbital calculation. So we'll know if it's going to hit us or not, even if we don't know how big a boom it will make if it does hit.

      --
      The correlation between ignorance of statistics and using "correlation is not causation" as an argument is close to 1.
    5. Re:2029 approach by Anonymous Coward · · Score: 4, Interesting

      "The real probability"? I suppose then the "real probability" of you buying a winning lottery ticket, or rolling 6 twenty consecutive times, etc, etc, are all 0 or 100% too.

      Yes, actually. That's what probability really is.
      It is not the event itself which is uncertain, but rather our knowledge of the event. In this type of situation, if we make a GUESS, the probability tells us how likely we are to have guessed correctly.

      Think about it like this. Take out a deck of cards, shuffle it, and set it face down. There is a card on the top. If you say the name of a card out loud, you have a 1/52 chance of saying the card which is actually on top. We can consider the actual value of that card to be uncertain from a mathematical point of view, but in reality its value is already fixed- you just don't know the value.

      In regards to the lottery ticket, we actually know a little bit more. If you do not purchase a ticket at all, we CAN say with 100% certainty that you do not hold the winning ticket. If you DO purchase a ticket, we cannot say for certain if you have the winning ticket or not, but the reality is that either you have a winning ticket, or you do not.

      The problem with your line of thinking is that you are confusing a prediction with an actuality. We use probability to determine future events when we have incomplete knowledge, once our knowledge of ALL factors which influence the event is complete, then it is no longer an unknown and we can say the event either will, or will not, occur. Or put another way, if you have access to all the data you're not predicting, you're simply calculating a result.

  7. Obligatory... by bmo · · Score: 4, Funny

    asteroid 99942 Apophis is actually bigger than we thought

    http://www.youtube.com/watch?v=PzZ4i8aWs_s

    --
    BMO

  8. Re:Homeowners insurance by Ackmo · · Score: 5, Funny

    Hmm. My insurance policy actually says, "act of Goa'uld". I always thought that was a typo.

  9. 1 Earth Diameter Close Pass by BoRegardless · · Score: 4, Insightful

    "In April 2029 the space rock will still make a very close pass with our planet, coming within 22,364 miles"

    Being the skeptical engineer, I would say there is also a chance that on its multihundred million mile trip over the next decade and a half all it would take to nudge the orbit a slight amount to make the close pass a hit would be an encounter with another large object that affected its orbit ever so slightly...the wrong way.

    That orbital perturbation is random & would simply not be predictable.

    1. Re:1 Earth Diameter Close Pass by girlintraining · · Score: 4, Insightful

      That orbital perturbation is random & would simply not be predictable.

      Not exactly. It's passing by earth again in another 15 years or so -- and its orbit has to pass through a very small space in order for Earth's gravity to alter it just that tiny smidge so that over the following 15 years, that few thousands of a degree change due to gravitational pull will close that 22,364 mile gap. It has to be spot on -- if the vector is even slightly off, it'll either get slingshot out of the solar system (or into one of the outer planets), or into the Sun.

      While you're right that the energy required to move the asteroid into a collision path is low, it has to be the precise amount, and at the precise vector. A random preturbation has a very low chance of being at both the correct energy level, and at the correct vector. And even many such random preturbations still wouldn't alter the orbit enough that if we looked for it on its next approach in a very narrow region of the sky, we couldn't find it. Which means we'll know its coming, and we'll have several years' warning to take action. I just hope they can clone Bruce Willis before then.

      --
      #fuckbeta #iamslashdot #dicemustdie
  10. Well, obviously... by mschaffer · · Score: 4, Funny

    Well, obviously the asteroid had passed through the trans-fat and high-fructose corn syrup nebulae between photos.

  11. different mirror by mschaffer · · Score: 4, Funny

    No, it just means that the astronomers are using the telescope that doesn't have the mirror with the words "objects are closer than they appear" on it.

  12. Re:Wait a minute by arth1 · · Score: 4, Interesting

    The issue is that mass is irrelevant when you're measuring how something is affected by gravity. This was the point of the (possibly apocryphal) experiments of Galileo. The force of the gravity on the object is proportional to the mass of the object, but the force needed to move the object is also proportional to its mass, so it all cancels out. Apophis will continue to follow the same path, no matter what its mass is.

    True, but a higher mass relative to the diameter means that solar winds have a lesser effect. Granted, that effect is small compared to the pull of Earth, Sol, Jupiter and (when close) Luna, but it might still be significant in calculating whether we're going to get hit or not.

  13. Pfft by kiddygrinder · · Score: 4, Funny

    You asteroid alarmists are getting ridiculous, there isn't a scientific consensus that asteroids even exist, let alone that they are caused by humans

    --
    This is a joke. I am joking. Joke joke joke.