Apophis to sweep closely past Earth on Jan. 9, 2013.doc
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Transcript of Apophis to sweep closely past Earth on Jan. 9, 2013.doc
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8/14/2019 Apophis to sweep closely past Earth on Jan. 9, 2013.doc
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Asteroid Apophis, which may hit Earth in 2036, will pass close by this week
January 08, 2013 8:34 AM
http://www.news.com.au/technology/sci-tech/asteroid-apophis-which-may-hit-earth-in-2036-will-pass-close-by-this-week/story-fn5fsgyc-12265!305351
A depiction of the orbit of the asteroid Apophis.
PLANET Earth will get a close look at a wandering demon when asteroid Apophis passes within a ew
million kilometres on Th!rsday"
99942 Apophis - named after the Egyptian demonic serpent-spirit of destruction - blasted itself into public
awareness back in 2004 when astronomers calculated a 1 in 4 chance of it hitting the Earth on 1! April
2029.
"ew data and fresh calculations ha#e all but ruled out the risk for 2029 - but e$posed a small chance that the
asteroid could get alarmingly close in 20!%.
&he !90m lump of space rock will be close enough to be seen in the night sky after it has passed its closest
point at 14. million kilometres later this week.
Astronomers are not sure about the e$act risk Apophis poses in 20!%.
&his is why a forest of telescopes will be pointed towards the asteroid as it comes into #iew on &hursday.
"A'A will use deep-space radarsat (oldstone) located in the *o+a#e desert in ,alifornia) and Arecibo in
uerto ico to scan the asteroid.
/sing new measurements of the asteroids distance and line-of-sight #elocity) we hope to reduce the orbitaluncertainties and e$tend the inter#al o#er which we can compute the motion into the future)/ "A'A et
ropulsion 3aboratorys 3ance enner said.
http://en.wikipedia.org/wiki/99942_Apophishttp://neo.jpl.nasa.gov/apophis/http://neo.jpl.nasa.gov/apophis/http://en.wikipedia.org/wiki/99942_Apophis -
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A fireball meteor over Groningen.
5f asteroid Apophis was to enter the Earths atmosphere) it would hit with the force of 100)000 6iroshima
bombs. icture7 obert *ikaelyan 8 "A'A
/5ts possible that the new measurements impro#e the orbit to the point that we can completely rule out an
impact./
&he asteroids mass) shape and spin need to be disco#ered to create the most precise possible calculations ofits orbit to determine +ust how much of a risk it will be in 20!%.
ussia has gone so far as to announce plans to land a homing beacon on Apophis in 2020 to guarantee
pinpoint accuracy.
&hats not to say it wont get close in 20297 5t is calculated to skim past at !0)000km. &he *oon orbits at
!)000km) and communication satellites at !%)000km.
Apophis is now on top of the otentially 6a:ardous Asteroids list maintained by the 5nternational
Astronomical nion.
5f the asteroid were to hit Earth in 20!%) it would e$plode with the power of 100)000 6iroshima nuclear
bombs. &housands of kilometres will be affected directly) and the cloud of smoke and dust will en#elop the
planet.
And we need to calculate Apophis orbit fast7 A meeting of near-Earth ob+ect e$perts in 3ondon last years
said it could take decades to in#ent) design and build the e;uipment necessary to deflect the space rock.
http://www.minorplanetcenter.org/iau/mpc.htmlhttp://www.minorplanetcenter.org/iau/mpc.htmlhttp://www.minorplanetcenter.org/iau/mpc.htmlhttp://www.minorplanetcenter.org/iau/mpc.htmlhttp://www.minorplanetcenter.org/iau/mpc.html -
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&he potentially dangerous asteroid was named after an ancient Egyptian snake-demon) Apophis.
< < < < < < < < < < < < < < < < < < < < < < < < < of Earth on ednesday) anuary 9) 201!) and which will come close again in
subse;uent years with an extremely remotepossibility of striking Earth in 20!%. 5n late 2012 and early 201!)
Apophis has been obser#able using both optical and radar e;uipment. &he data collected around now are
e$pected to make possible a significant impro#ement in our understanding of the orbit of Apophis and remo#e
any possibility for an Earth impact on April 1!) 20!%. 6owe#er) as Ba#id 6elfand of ,olumbia said when
Earth'ky inter#iewed him in 2010 on killer asteroids)the risk from Apophis is already essentially zero.
hat does essentially zeromean e$actlyC 3etDs re#iew some history. hen Apophis was disco#ered in 2004)
astronomers calculated that there was a #ery small probability =up to 2.F> that it would strike the Earth in
2029. &hat was clearly unsettling) but the concern was short-li#ed. &he 2029 impact possibility was ;uickly
ruled out) but) almost as ;uickly) another possibility reared its head7 a possible impact in 20!%. ?or a time)
http://earthsky.org/space/david-helfand-speaks-of-risk-from-killer-asteroidshttp://earthsky.org/space/david-helfand-speaks-of-risk-from-killer-asteroidshttp://en.es-static.us/upl/2011/02/arecibo_telescope_puerto_rico.gifhttp://en.es-static.us/upl/2006/01/aphophis_450.jpghttp://earthsky.org/space/david-helfand-speaks-of-risk-from-killer-asteroids -
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astronomers thought there was a 1-in-4)000 chance that Apophis would strike Earth on April 1!) 20!%. &hen)
in Gctober 2009) the numbers were updated again) and the impact possibility decreased again. ,urrently) the
chance of an impact with Earth by asteroid Apophis in 20!% has dropped to about 1-in-20)000. hile greater
than your chance of winning a lottery =many millions to one>) itDs still #ery #ery unlikely. &hatDs the number
Ba#id 6elfand calls essentially zero. Astronomers belie#e the possibility will drop to absolutely :ero after the
early 201! pass by Apophis.
hat would happen if Apophis did strike EarthC esearchers say it would cause an e$plosion 100)000 times
more powerful than the nuclear weapon detonated o#er 6iroshima.
(ratuitous and wholly imaginary asteroid Apophis collision pic. "ot likelyH
'till) Apophis is more a curiosity than a threat) at this point. As things stand today) ignoring the new orbit
calculations in the coming months =which might change e#erything 5 say ne$t>) astronomers speak of a %00-
meter-wide keyhole through which Apophis would ha#e to pass in 2029) in order to be on a collision course
with Earth in 20!%. hen you work in astronomy) and ha#e some concept of how #ast space is) that keyhole
seems almost ridiculously small. Earth'ky spoke to Bon Ieomans) who is manager of "A'ADs"ear Earth
Gb+ect rogram.'peaking of the Apophis pass in 2029) he said that) yes) it will come close7
5n fact) it will get beneath the geosynchronous satellites Jwhich are 2%)000 miles upK) the same satellites that areprobably used to beam your radio signals to your listeners.'o thatDs kind of e$citing. ut it wonDt hit the Earth.
http://neo.jpl.nasa.gov/index.htmlhttp://neo.jpl.nasa.gov/index.htmlhttp://neo.jpl.nasa.gov/index.htmlhttp://earthsky.org/press/earthsky-wins-award-for-excellence-in-population-reporting-in-the-year-of-7-billionhttp://earthsky.org/press/earthsky-wins-award-for-excellence-in-population-reporting-in-the-year-of-7-billionhttp://en.es-static.us/upl/2006/01/apophis_impact_450.jpghttp://neo.jpl.nasa.gov/index.htmlhttp://neo.jpl.nasa.gov/index.htmlhttp://earthsky.org/press/earthsky-wins-award-for-excellence-in-population-reporting-in-the-year-of-7-billion -
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Artist
Ieomans also said that) in the #ery remote case where the impact probability does not go to :ero as 20!%approaches L if the asteroid does seem that it willcome too close for comfort L there still would be time to send
spacecraft to Apophis and deflect away from Earth.
Astronomers ha#e been meeting periodically since the 1990s on ways to deflect asteroids) should they come too
close. &he ways include sending nuclear weapons to e$plode on them or near them L putting up a satellite that
gra#itationally tugs at the asteroid a little bit) so its orbit changes e#er so slightly +ust enough to miss the Earth L
or outfitting the asteroid with a mass dri#erthat would e+ect material from the asteroid into space) decreasing its
mass and thereby changing its orbit.
&here are more asteroid collision avoidance strategies) which you can read about on ikipedia.'o scientists
are) indeed) contemplating the physics and engineering challenges of keeping us safe from asteroid collisions.
y the way) in ?ebruary 2011) Asteroid Apophis was back in the news) this time due to the release of a report
by ussian scientists) which the 6uffington ost chose topresentin pairing with a scary) factually incorrect and
#ery misleading #ideo. hen 5 looked +ust now) the story was still there) but the #ideo didnDt come up so maybe
they remo#ed it. Bon Ieomans commented7
&he 6uffington ost #ideo was creepy and all wrong.
'till) if you happened to see that #ideo in ?ebruary 2011 on 6uffo or elsewhere) donDt belie#e it. Asteroid
Apophis is noton a sure collision course with Earth in 20!%) but astronomers doha#e their eyes on this ob+ect)
and L if a too-close pass seems imminent L weDll ha#e time for a deflection #ia spacecraft.
ottom line7 At present) there is a 1-in-20)000 chance that asteroid Apophis will strike Earth in 20!%. &hat
#ery remote chance is e$pected to drop to :ero after the early 201! pass of Apophis near Earth) which will occur
on anuary 9.
Ba#id 6elfand on risk from killer asteroids
http://www.daviddarling.info/encyclopedia/M/mass_driver.htmlhttp://en.wikipedia.org/wiki/Asteroid_impact_avoidance#Collision_avoidance_strategieshttp://www.huffingtonpost.com/2011/02/09/apophis-asteroid-2036-video_n_820800.htmlhttp://www.huffingtonpost.com/2011/02/09/apophis-asteroid-2036-video_n_820800.htmlhttp://www.huffingtonpost.com/2011/02/09/apophis-asteroid-2036-video_n_820800.htmlhttp://earthsky.org/space/david-helfand-speaks-of-risk-from-killer-asteroidshttp://en.es-static.us/upl/2011/02/mass_driver.jpghttp://www.daviddarling.info/encyclopedia/M/mass_driver.htmlhttp://en.wikipedia.org/wiki/Asteroid_impact_avoidance#Collision_avoidance_strategieshttp://www.huffingtonpost.com/2011/02/09/apophis-asteroid-2036-video_n_820800.htmlhttp://earthsky.org/space/david-helfand-speaks-of-risk-from-killer-asteroids