back to article Asteroid zips past Earth

An asteroid spotted by Australian astronomers early in the week missed Earth by just 5.3 million kilometres. “2012 LZ1” was observed from Australia’s Siding Springs Observatory last Sunday, June 10th. At around 500m in diameter, the rock is considered hazardous. Happily, 2012 LZ1 slipped by well outside the orbit of the moon …

COMMENTS

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  1. Esskay
    Mushroom

    Can't wait...

    To see how many 2012 Apocalypse nutters try to use this as a get out of gaol card... "the mayans would have been right, but their calculations were slightly out, etc etc"

    1. Anonymous Coward
      Anonymous Coward

      Statistically I have better odds being hit by a meteor than winning the national lottery.

      Maybe my numbers are about to come up!

      1. Martin Budden Silver badge
        Boffin

        Re. Statistically...

        Wouldn't that depend on how many lottery tickets you buy?

        1. Annihilator
          Joke

          Re: Re. Statistically...

          Warning... bad maths to follow...

          Statistically there's more chance of me winning the lottery than being struck by an asteroid. But it's a pretty likely event that *someone* will win the lottery.

          But consider the odds from the asteroids perspective. There's similar odds of that asteroid being hit by the earth - unlikely, but if lots of asteroids buy lottery tickets to hit the earth, there's a fairly good chance that one of them will "win"... The Mayans were right, head for the bunkers/hills!

      2. TeeCee Gold badge
        Facepalm

        You'll be winning a tenner which, in lottery terms, is the equivalent of a 500m rock missing the prize by 5.3 million miles.

  2. Steve Carr 1
    Holmes

    4 days warning, and it's 500m across....

    ....good thing people are watching for them, but heck - that's not a lot of warning if it was spotted on a collision course. Hope they have some plans in place for that.

    1. Voland's right hand Silver badge
      Devil

      Re: 4 days warning, and it's 500m across....

      I had the same thought.

      So much for all the effort into monitoring near earth object and so much for all the noise and panic around various 10-30m objects.

    2. Bad Beaver
      Devil

      Re: 4 days warning, and it's 500m across....

      Right. Depensing on your location, at 500m it might still be worth it to get "elsewhere" one on this little ball. Could get a little crowded at the airports.

    3. S4qFBxkFFg

      Re: 4 days warning, and it's 500m across....

      Hmm, it's *possibly* enough time; I recall reading that a particular nuclear explosive device could vapourise a sphere of 100m diameter of rock so maybe 100 of these would be enough to reduce that kind of asteroid to bits small enough to burn up in the atmosphere.

      So the question is, how many rockets can be launched in 4 days, and how many nukes can you stuff in each one?

      1. Jonathan Richards 1
        Go

        Re: 4 days warning, and it's 500m across....

        @S4qFBxkFFg, who asked :

        ...how many rockets can be launched in 4 days, and how many nukes can you stuff in each one?

        I was about to suggest that you need to set aside several years of international diplomacy to renegotiate the terms of the Treaty on Principles Governing the Activities of States in the Exploration and Use of Outer Space, including the Moon and Other Celestial Bodies, because I believed that Nukes in Spa-a-a-a-ce were forbidden by it. However, Article IV declares that "States Parties to the Treaty undertake not to place in orbit around the earth any objects carrying nuclear weapons or any other kinds of weapons of mass destruction, install such weapons on celestial bodies, or station such weapons in outer space in any other manner."

        OK! Nukes on an intercept course for an inbound mountain are not in orbit, nor are they "stationed", so we can stand the lawyers down, and maybe even send them to observe at about the site(s) of impact for thousands of tons of irradiated gravel! Result!

    4. David Pollard

      Re: 4 days warning, and it's 500m across....

      "...plans in place for that."

      Nukes in space. It's the only way we can survive.

    5. Tank boy
      Black Helicopters

      Re: 4 days warning, and it's 500m across....

      NASA sent Bruce Willis and a crew of roughnecks into space to divert the course of the asteroid months ago.

  3. Anonymous Coward
    Anonymous Coward

    "at about 20:00AM this morning"

    That must be in Aardvark Standard Time.

    1. Anonymous Coward
      Anonymous Coward

      Re: "at about 20:00AM this morning"

      Australian time, understandable confusion for them, they are on the other side of the world.

      1. Code Monkey
        Coat

        Re: "at about 20:00AM this morning"

        "Australian time, understandable confusion for them, they are on the other side of the world."

        ... and upside down

        1. VinceH
          Joke

          Re: "at about 20:00AM this morning"

          ' "Australian time, understandable confusion for them, they are on the other side of the world."

          ... and upside down'

          Aha! So it was two minutes past midnight!

          1. TeeCee Gold badge
            Coat

            Re: "at about 20:00AM this morning"

            Er, that's five minutes past midnight. They must be using a Nixie clock with Russian tubes.

    2. Interceptor

      Re: "at about 20:00AM this morning"

      "At the tone, the time will be 26 Railroad."

  4. BWJ

    When too much is too little

    Missing Earth by "just 5.3 million kilometers." That's more than 10 times the distance the Moon is from Earth. Talk about just journalistic licence!

    1. Nick Ryan Silver badge

      Re: When too much is too little

      In astronomical terms that's still considered rather too damn close.

      Others have made it rather closer, such as those that have skimmed off the atmosphere like a pebble over water (you can't really get much close without an impact), but most are suitably far away but close enough to be a concern. The concerns are generally due to the huge number of variables in calculating orbital trajectories of less massive objects and the vagaries of the measurements available.

  5. wibble001
    Joke

    Haha, stupid aliens, ya missed!

  6. Crisp
    Coat

    5.3 million kilometers away

    I guess that's too far away to hit it with a mining laser and scoop up free metals?

  7. macole111
    Mushroom

    Blowing up

    We would never try to blow one up, just nudge it off course by knocking into it. Think about it, we would then have hundreds of still dangerous bits of rock.

  8. Graham Marsden
    Mushroom

    /me

    ducks. Phew! That was a close one...

  9. JeffyPooh
    Pint

    How big a hole would it have made if it had hit the Earth?

    I'll go look it up.

    Ever notice that most of these things arrived in-between Tuesday and Friday? I recommend lunch out on Tuesdays, as well as Fridays. One never knows...

    1. JeffyPooh
      Pint

      Re: How big a hole would it have made if it had hit the Earth?

      Wow. It'd take out a medium size US state. Or make a tsunami when it hit the ocean (75% odds),

      It'll certainly make the evening news...

      1. Nunyabiznes

        Re: How big a hole would it have made if it had hit the Earth?

        With a land strike the resulting atmospheric debris would probably be a bigger concern globally. Whoever was standing on the X might disagree.

        Think of it as nature's way of putting soot in the upper atmosphere to reflect the sun's radiation and cool this rock off.

        1. Dixie Nourmous

          Re: How big a hole would it have made if it had hit the Earth?

          Calculator here:-

          http://impact.ese.ic.ac.uk/ImpactEffects/

          1. Dixie Nourmous

            Re: How big a hole would it have made if it had hit the Earth?

            A few random figures later:-

            our Inputs:

            Distance from Impact: 10.00 km ( = 6.21 miles )

            Projectile diameter: 500.00 meters ( = 1640.00 feet )

            Projectile Density: 8000 kg/m3

            Impact Velocity: 72.00 km per second ( = 44.70 miles per second ) (Your chosen velocity is higher than the maximum for an object orbiting the sun)

            Impact Angle: 10 degrees

            Target Density: 2500 kg/m3

            Target Type: Sedimentary Rock

            Energy:

            Energy before atmospheric entry: 1.36 x 1021 Joules = 3.24 x 105 MegaTons TNT

            The average interval between impacts of this size somewhere on Earth during the last 4 billion years is 1.9 x 106years

            Major Global Changes:

            The Earth is not strongly disturbed by the impact and loses negligible mass.

            The impact does not make a noticeable change in the tilt of Earth's axis (< 5 hundreths of a degree).

            The impact does not shift the Earth's orbit noticeably.

            So this = BIG HOLE....

            1. Dixie Nourmous

              Re: How big a hole would it have made if it had hit the Earth?

              Crater shape is normal in spite of atmospheric crushing; fragments are not significantly dispersed.

              Transient Crater Diameter: 9.78 km ( = 6.07 miles )

              Transient Crater Depth: 3.46 km ( = 2.15 miles )

              Final Crater Diameter: 13.2 km ( = 8.22 miles )

              Final Crater Depth: 644 meters ( = 2110 feet )

              The crater formed is a complex crater.

              The volume of the target melted or vaporized is 1.81 km3 = 0.435 miles3

              Roughly half the melt remains in the crater, where its average thickness is 24.1 meters ( = 79.2 feet ).

  10. Stevie

    Bah!

    5.3 million kilometres. Would that be 5.3 trilometres?

  11. MajorTom

    Big Hole

    My very sketchy research gives me the idea that a 500 m PHO such as this, if it were to strike earth, may yield an energy release equivalent to 3 Gigatons, or 60 Tsar Bombas. Or a "9" on the Torino Scale. Not a civilization-ender, but certainly a city-killer.

  12. Mark Eccleston

    Hardware Problem?

    I saw the video attached to the article. Are you sure all this fuss is not just from a stuck pixel on the monitor?

  13. elderlybloke
    Pirate

    We had a close call in 1974

    There were videos and still shots on Astronomy magazine of an object that went over USA in daylight and was apparently only about 20 miles up.

    The glow of the object and the trail were very bright even though it was in broad daylight.

    Estimates of the mass varied but it was probably between 500,000 and 1,000,000 Tons (or Tonnes).

    The bang would have been very impressive the path had been 20miles (or 21 miles) closer to Earth.

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