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Vocapedia > Space > Asteroids, Comets, Meteorites, Meteors

 

 

 

 

Did Asteroids Bring Water to Earth? | ScienceTake        The New York Times        15 May 2018

YouTube

https://www.youtube.com/
watch?v=UtoGxZt42_0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The Guardian        p. 9        7 March 2007

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

It's called Apophis. It's 390m wide.

And it could hit Earth in 31 years time

Scientists call for plans to change asteroid's path

Developing technology could take decades

G

Wednesday December 7, 2005

https://www.theguardian.com/science/2005/dec/07/
spaceexploration.research 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

An artist's impression of an asteroid passing Earth.

Photograph: Getty Images

G

29.9.2004

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

near-Earth objects    NEOs

 

asteroids and comets

— mineral-rich bodies

bathed in a continuous

flood of sunlight

 

http://www.theguardian.com/science/2014/feb/17/
asteroid-2000-em26-fly-close-earth-potentially-hazardous

 

http://www.nytimes.com/2010/10/26/opinion/26schweickart.html

 

https://www.theguardian.com/science/2005/dec/07/spaceexploration.research 

https://www.theguardian.com/science/2005/apr/14/research.science2 

http://neo.jpl.nasa.gov/news/news_archives0206.html

 

 

 

 

cartoons > Cagle > Asteroid impact        February 2013

http://www.cagle.com/news/asteroid-impact/

 

 

 

 

Near-Earth asteroids

http://www.guardian.co.uk/science/2011/jun/27/
asteroid-poses-no-threat-earth

http://www.nasa.gov/topics/solarsystem/features/neo20110624.html

 

http://www.usatoday.com/tech/science/space/2007-02-12-
asteroid_x.htm

 

 

 

 

asteroid detectors        UK

https://www.theguardian.com/science/2013/feb/16/
scientists-earth-asteroid 

 

 

 

 

close encounter        UK

https://www.theguardian.com/science/2017/aug/11/
close-encounter-asteroid-2012-tc4-size-of-a-house-near-miss-with-earth

 

https://www.theguardian.com/science/2011/jun/27/
asteroid-poses-no-threat-earth 

 

 

 

 

asteroid strikes

https://www.theguardian.com/science/2016/may/25/
dinosaur-extinction-only-half-the-story-of-killer-asteroids-impact-plant-fossil

http://science.sciencemag.org/content/327/5970/1214.full

 

http://www.nytimes.com/2013/11/07/
science/space/more-large-asteroid-strikes-are-likely-scientists-find.html

http://www.nytimes.com/2013/02/16/world/europe/
meteorite-fragments-are-said-to-rain-down-on-siberia.html

 

 

 

 

Chicxulub asteroid

— so named for the crater

it carved out

around the Gulf of Mexico —

sent columns of rock

into Earth’s atmosphere,

incinerated

the planet’s forests

and drove tsunamis

far across the oceans.

 

(...)

New research

now makes the case

that the same incident

that helped bring an end

to the reign of the dinosaurs

also acidified the planet’s oceans,

disrupted the food chain

hat sustained life underwater

and resulted in a mass extinction.

https://www.nytimes.com/2019/10/21/
science/chicxulub-asteroid-ocean-acid.html

 

 

https://www.nytimes.com/2019/10/21/
science/chicxulub-asteroid-ocean-acid.html

 

 

 

 

 

 

 

 

 

 

 

 

 

 

space rock / meteor / asteroid        UK / USA

 

https://www.theguardian.com/science/meteors

 

 

https://www.nytimes.com/2019/12/12/
science/osiris-rex-nasa-asteroid-bennu.html

 

https://www.nytimes.com/2019/10/21/
science/chicxulub-asteroid-ocean-acid.html

 

https://www.npr.org/2019/04/29/
718296681/this-week-nasa-is-pretending-an-asteroid-is-on-its-way-to-smack-the-earth

 

 

 

 

https://www.npr.org/sections/thetwo-way/2018/05/24/
614105843/asteroid-impact-that-wiped-out-the-dinosaurs-also-caused-abrupt-global-warming

 

https://www.youtube.com/
watch?v=UtoGxZt42_0 - NYT - May 15, 2018

 

 

 

 

https://www.npr.org/sections/thetwo-way/2017/12/12/
570206648/an-asteroid-gets-its-close-up-as-gemenids-light-up-the-sky

 

http://www.npr.org/sections/thetwo-way/2017/10/20/
559094041/orionid-meteor-shower-will-peak-overnight-with-best-show-before-dawn

 

https://www.theguardian.com/science/2017/aug/11/
close-encounter-asteroid-2012-tc4-size-of-a-house-near-miss-with-earth

 

http://www.npr.org/sections/thetwo-way/2017/04/19/
524680317/an-asteroid-is-swinging-by-earth-today-for-its-closest-visit-in-400-years

 

 

 

 

http://www.npr.org/sections/thetwo-way/2016/11/22/
503013290/scientists-say-dinosaur-killing-asteroid-made-earths-surface-act-like-liquid

 

http://www.npr.org/sections/thetwo-way/2016/10/30/
499751470/nasas-new-intruder-alert-system-spots-an-incoming-asteroid

 

https://www.theguardian.com/science/2016/may/25/
dinosaur-extinction-only-half-the-story-of-killer-asteroids-impact-plant-fossil

 

http://www.npr.org/sections/thetwo-way/2016/05/06/
476871766/geologists-find-clues-in-crater-left-by-dinosaur-killing-asteroid

 

 

 

 

http://www.theguardian.com/science/2014/jul/28/
dinosaurs-asteroid-bad-timing-killed-off-biodiversity-edinburgh-scientists

http://www.theguardian.com/science/2014/feb/17/
asteroid-2000-em26-fly-close-earth-potentially-hazardous

http://www.theguardian.com/science/2014/jan/22/
giant-asteroid-steam-ceres

 

http://www.nytimes.com/2013/11/07/
science/space/more-large-asteroid-strikes-are-likely-scientists-find.html

http://www.theguardian.com/science/2013/nov/06/chelyabinsk-meteor-russia

http://www.theguardian.com/science/2013/aug/16/
hambleton-chelyabinsk-meteorite-auction-rob-elliott

http://www.theguardian.com/science/video/2013/feb/15/asteroid-2012-da14-nasa-video

 

http://www.guardian.co.uk/science/2012/mar/25/asteroid-headed-for-earth-laser

http://www.guardian.co.uk/science/2012/apr/24/tech-tycoons-asteroid-mining-venture

 

http://www.nytimes.com/2010/10/26/
opinion/26schweickart.html

 

http://www.usatoday.com/tech/science/space/2007-02-12-
asteroid_x.htm

 

https://www.theguardian.com/science/2005/dec/07/
spaceexploration.research

 

 

 

 

 

 

 

dinosaur-killing asteroid        USA

http://www.npr.org/sections/thetwo-way/2016/11/22/
503013290/scientists-say-dinosaur-killing-asteroid-made-earths-surface-act-like-liquid

 

 

 

 

NASA > tool > computer program

for detecting potentially dangerous asteroids        USA

http://www.npr.org/sections/thetwo-way/2016/10/30/
499751470/nasas-new-intruder-alert-system-spots-an-incoming-asteroid

 

 

 

 

asteroid 2014 JO25        USA

http://www.npr.org/sections/thetwo-way/2017/04/19/
524680317/an-asteroid-is-swinging-by-earth-today-for-its-closest-visit-in-400-years

 

 

 

 

Ceres        UK / USA

 

600 miles wide,

the largest of the asteroids

between Mars and Jupiter.

 

(...) a giant world

of rock and ice

 

(...)  “Ceres

has 38 percent

of the area

of the continental

United States.

 

It’s actually the largest body

between the sun and Pluto

that a spacecraft

has not yet visited.”

http://www.nytimes.com/2015/01/20/science/
nasa-spacecraft-get-a-closer-look-at-pluto-and-ceres-whatever-they-may-be.html

 

http://www.npr.org/blogs/thetwo-way/2015/03/06/
391028906/nasa-probe-to-arrive-at-dwarf-planet

http://www.theguardian.com/science/2015/mar/01/
dawn-ceres-nasa-probe-enter-dwarf-planet-orbit

http://www.nytimes.com/2015/01/20/
science/nasa-spacecraft-get-a-closer-look-at-pluto-and-ceres-
whatever-they-may-be.html

 

 

 

 

 

asteroid >  2013 TV135        UK

http://www.theguardian.com/science/across-the-universe/2013/oct/18/
asteroid-2013-tv135-doomsday-again

 

 

 

 

asteroid > 2012 DA14

http://www.guardian.co.uk/science/2013/feb/15/
asteroid-misses-earth-meteor-strike

http://www.nytimes.com/2013/02/10/
opinion/sunday/beware-of-errant-asteroids.html

http://www.guardian.co.uk/science/2013/feb/08/
asteroid-will-miss-earth-says-nasa

http://www.guardian.co.uk/science/video/2013/feb/07/
asteroid-earth-animation

 

 

 

 

asteroid > Apophis        UK

http://www.guardian.co.uk/science/video/2013/jan/10/
apophis-doomsday-asteroid-earth-video

http://www.guardian.co.uk/science/across-the-universe/2013/jan/07/
apophis-potentially-hazardous-asteroid-earth-wednesday

 

 

 

 

asteroid mining        UK

http://www.guardian.co.uk/science/across-the-universe/2013/jan/23/
asteroid-mining-deep-space-industries

 

 

 

 

Asteroid mining:

how it might work – interactive        UK        April 24, 2012

http://www.guardian.co.uk/science/interactive/2012/apr/24/
asteroid-mining-how-work-interactive

 

 

 

 

asteroid's path

 

 

 

 

a 390-metre wide asteroid

 

 

 

 

interstellar object        USA

https://www.npr.org/sections/thetwo-way/2017/12/12/
570167473/astronomers-want-to-know-does-this-interstellar-visitor-have-a-message-for-us

 

 

 

 

 

 

 

 

 

 

 

 

 

 

reach the Earth's atmosphere

 

 

 

 

break up

 

 

 

 

Earth-bound asteroid        UK

https://www.theguardian.com/science/2005/dec/07/
spaceexploration.research  

 

https://www.theguardian.com/science/2004/jul/16/
spaceexploration.research 

 

 

 

 

killer asteroid        UK

https://www.theguardian.com/science/2006/nov/17/
spaceexploration.internationalnews 

 

 

 

 

near-miss / near miss        UK

http://www.theguardian.com/science/2014/oct/19/
comet-siding-spring-rare-near-miss-mars

 

http://www.nytimes.com/2010/10/26/
opinion/26schweickart.html

 

https://www.theguardian.com/science/2006/jul/03/
spaceexploration.uknews 

 

 

 

 

fly-past        UK

http://www.theguardian.com/science/2014/oct/19/
comet-siding-spring-rare-near-miss-mars

 

 

 

 

deflect the asteroid        UK

https://www.theguardian.com/science/2005/dec/07/
spaceexploration.research 

 

 

 

 

smack into Earth        USA

http://usatoday30.usatoday.com/tech/science/space/2007-02-12-
asteroid_x.htm

 

 

 

collision with Earth        UK

https://www.theguardian.com/science/2007/mar/07/
spaceexploration.frontpagenews

 

 

 

 

hit

 

 

 

 

'nuclear winter'        USA

http://www.usatoday.com/tech/science/space/2007-02-12-
asteroid_x.htm

 

 

 

 

close call

 

 

 

 

 

 

 

 

 

 

 

 

 

 

meteorite / meteor

http://www.npr.org/sections/thetwo-way/2016/06/15/
482195719/scientists-say-theyve-unearthed-a-completely-new-kind-of-meteorite

 

http://www.theguardian.com/science/2014/feb/24/
meteorite-moon-largest-lunar-impact-recorded

 

http://www.theguardian.com/science/2013/nov/06/
chelyabinsk-meteor-russia

http://www.theguardian.com/science/2013/aug/16/
hambleton-chelyabinsk-meteorite-auction-rob-elliott

http://www.guardian.co.uk/science/video/2013/may/18/
meteor-crashes-moons-surface-flash-video

http://www.guardian.co.uk/commentisfree/2013/feb/15/
meaning-of-meteors

http://www.nytimes.com/2013/02/16/science/space/
size-of-blast-and-number-of-injuries-are-seen-as-rare-for-a-rock-from-space.html

http://www.nytimes.com/2013/02/16/world/europe/
a-flash-in-russian-skies-as-inspiration-for-fantasy.html

http://www.nytimes.com/2013/02/16/world/europe/
meteorite-fragments-are-said-to-rain-down-on-siberia.html

http://www.theguardian.com/science/2013/aug/16/hambleton-chelyabinsk-meteorite-auction-rob-elliott

http://www.guardian.co.uk/science/datablog/interactive/2013/may/08/meteorites-2500bc-interactive

http://cityroom.blogs.nytimes.com/2013/02/22/flashy-meteors-fall-on-us-too/

http://www.guardian.co.uk/world/gallery/2013/feb/15/meteorite-explosion-russia-in-pictures

http://www.guardian.co.uk/science/video/2013/feb/16/russian-meteorite-scientists-search-video

http://www.guardian.co.uk/science/2013/feb/15/meteorite-russia-key-questions-answered

http://www.guardian.co.uk/world/2013/feb/15/meteorite-footage-russia-dashcams

http://www.guardian.co.uk/science/2013/jan/03/mars-meteor-water-sahara-analysis

 

http://www.guardian.co.uk/science/across-the-universe/2012/aug/10/
perseid-meteor-shower-astronomy

 

http://www.guardian.co.uk/science/audio/2011/jan/10/
science-weekly-podcast-meteors-ted-nield

 

http://www.usatoday.com/tech/science/space/2008-11-23-
meteor-canada_N.htm

 

http://www.usatoday.com/tech/science/space/2007-01-11-
meteorite-bathroom_x.htm

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Eta Aquariids meteor shower        USA

https://www.nytimes.com/2019/05/05/
science/eta-aquariids-meteor-shower.html

 

 

 

 

 annual Perseid meteor shower        USA

http://www.npr.org/blogs/thetwo-way/2014/08/12/
339924823/the-perseid-meteor-shower-due-to-shine-tonight

 

 

 

 

The Perseids        August 2013

 

the year's

most spectacular

meteor shower

for viewers

in the northern hemisphere

 

The Perseids

were once part

of comet Swift-Tuttle.

 

At 27 kilometres across,

this is one of the largest.

 

It orbits the sun

every 133 years

and last passed by

in 1992.

 

Whenever it approaches,

the heat of the sun

disintegrates its ice,

creating a dusty tail

and replenishing

the Perseid stream.

 

The Earth

passes through this stream

every August,

sparking the meteor shower.

 

Each one of the meteors,

sometimes called shooting stars,

that you see

is a tiny speck of dust as old

as the formation of Earth

and the other planets,

4.6bn years ago.

 

It burns with incandescent glory

because it has hit our atmosphere

at a speed

of 160,000 kilometres per hour

(100,000 miles per hour).

 

This creates a shockwave

that compresses

a pocket of air

in front of the dust grain

and raises it to a temperature

of a few thousand degrees.

 

This is enough

to burn up the dust

and create a bright meteor.

 

Swift Tuttle

is the largest object

to regularly pass Earth.

 

Its orbit

is known well enough

for astronomers to believe

it does not pose

a collision hazard

for at least

the next 2,000 years.

http://www.theguardian.com/science/across-the-universe/2013/aug/09/perseid-meteor-shower-2013-best-view

 

 

http://www.theguardian.com/science/across-the-universe/2013/aug/09/
perseid-meteor-shower-2013-best-view

 

http://www.theguardian.com/science/video/2013/aug/13/
perseids-meteor-shower-timelapse-video

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The Tunguska event:

a Siberian meteor mystery from 1908

http://www.nytimes.com/2013/02/15/
science/meteor-not-siberias-first-brush-with-falling-space.html

http://www.guardian.co.uk/theguardian/from-the-archive-blog/2013/feb/08/
tunguska-asteroid-comet-1908-siberia

 

 

 

 

Every meteorite fall on earth mapped        UK        15 February 2013

 

Or at least those we know about.

 

And where are

the known meteorite landing places

on earth?

 

These impact zones show

where scientists have found meteorites,

or the impact craters of meteorites,

some dating back

as far as the year 2,300BC.

 

The data

is from the US Meteorological Society

and doesn't show those places

where meteorites may have fallen

but not been discovered

http://www.guardian.co.uk/news/datablog/interactive/2013/feb/15/
meteorite-fall-map

 

 

 

 

fireball        USA

http://cityroom.blogs.nytimes.com/2013/02/22/
flashy-meteors-fall-on-us-too/

 

 

 

 

Sentinel teslescope        UK

http://www.guardian.co.uk/commentisfree/2013/feb/15/
meteor-strike-asteroid-pass-sentinel-telescope

 

 

 

 

 

 

 

 

 

 

 

 

 

 

comet        UK / USA

 

https://www.theguardian.com/science/comets

 

 

https://www.npr.org/2019/12/05/
784898213/a-comet-from-another-star-hints-that-our-solar-system-isnt-one-of-a-kind

 

https://www.theguardian.com/science/video/2016/sep/29/
rosetta-space-mission-a-european-success-story-video-explainer

 

http://www.nytimes.com/2015/06/15/world/
philae-spacecraft-reawakens-on-a-speeding-comet-with-data-for-scientists.html

http://www.nytimes.com/interactive/2015/03/20/science/space/rosetta-comet-photos.html

 

http://www.nytimes.com/2014/11/15/world/europe/spacecraft-on-comet-drills-for-data-as-its-power-fades.html

http://www.nytimes.com/2014/11/08/science/space/bright-specks-of-comet-dust-light-up-martian-sky.html

http://www.theguardian.com/science/2014/nov/01/rosetta-comet-space-mission-nears-end

http://www.theguardian.com/science/2014/oct/19/comet-siding-spring-rare-near-miss-mars

http://www.nytimes.com/2014/08/07/science/space/spacecraft-pulls-alongside-comet.html

http://www.theguardian.com/science/2014/jul/20/
comet-67p-rosetta-probe-close-encounter-origins-of-life-churyumov-gerasimenko

 

http://www.nytimes.com/2013/11/30/science/space/comet-presumed-dead-shows-new-life.html

http://www.theguardian.com/science/video/2013/nov/29/comet-ison-vanish-space-video

http://www.theguardian.com/science/2013/nov/28/comet-ison-sun

http://www.nytimes.com/2013/11/27/us/comet-nears-sun-offering-planetary-clues.html

http://www.guardian.co.uk/science/across-the-universe/2013/jan/04/ison-comet-century

 

http://www.nytimes.com/2011/02/14/science/space/14comet.html

 

http://www.nytimes.com/2010/11/23/us/23marsden.html

 

http://www.usatoday.com/tech/science/space/2006-01-11-stardust-return_x.htm

 

http://www.nytimes.com/2005/07/05/science/05comet.html

 

http://www.theguardian.com/science/2004/jan/03/spaceexploration.research

 

 

 

 

Comet 45P/Honda-Mrkos-Pajdusáková        USA

http://www.npr.org/sections/thetwo-way/2017/02/11/
514688792/photos-green-comet-snow-moon-and-eclipse-make-for-a-space-trifecta

 

 

 

 

Comet 67P/Churyumov-Gerasimenko        UK / USA

https://www.theguardian.com/science/video/2016/sep/29/
rosetta-space-mission-a-european-success-story-video-explainer

https://www.theguardian.com/science/2016/may/27/
comet-67p-atmospehere-contains-chemicals-of-life-rosetta-mission-glycine

 

http://www.theguardian.com/science/2015/jul/30/
rosetta-probe-studies-released-revealing-fullest-picture-of-comet-yet

http://www.nytimes.com/2015/06/15/world/
philae-spacecraft-reawakens-on-a-speeding-comet-with-data-for-scientists.html

 

 

 

 

comet dust        USA

https://stardustnext.jpl.nasa.gov/index.html

 

http://www.usatoday.com/tech/science/space/2006-02-20-
stardust-particles_x.htm

 

 

 

 

comet chaser / space probe > Rosetta        UK

https://www.theguardian.com/science/rosetta-space-probe

 

 

https://www.theguardian.com/science/video/2016/sep/29/
rosetta-space-mission-a-european-success-story-video-explainer

https://www.theguardian.com/science/2016/may/27/
comet-67p-atmospehere-contains-chemicals-of-life-rosetta-mission-glycine

 

http://www.theguardian.com/science/2015/jul/30/
rosetta-probe-studies-released-revealing-fullest-picture-of-comet-yet

 

http://www.theguardian.com/science/2014/nov/01/
rosetta-comet-space-mission-nears-end

http://www.theguardian.com/science/2014/jan/17/
rosetta-comet-chury-esa-67p-churyumov-erasimenko

 

 

 

 

gather data        UK

https://www.theguardian.com/science/video/2016/sep/29/
rosetta-space-mission-a-european-success-story-video-explainer

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

An artist's rendering

shows NASA's Stardust spacecraft closing in

on Comet Wild 2.

 

After travelling about 2 billion miles

in just under five years,

Stardust is set to come

within 186 miles of the comet

on Friday, January 2, 2004.

 

Using a "cometary catcher's mitt"

filled with a special material called aerogel,

Stardust will collect particles from Wild 2

and bring them back to Earth in January 2006.

 

Photo Credit: NASA/JPL

 

Related

http://www.usatoday.com/tech/science/space/2006-01-11-stardust-return_x.htm

http://stardustnext.jpl.nasa.gov/index.html

 

 

 

 

 

 

 

 

 

 

 

 

 


Beware of Errant Asteroids

 

February 9, 2013

The New York Times

By DONALD K. YEOMANS

 

PASADENA, Calif.

ON Feb. 15, an asteroid designated 2012 DA14 will pass safely within about 17,200 miles of Earth’s surface — closer than the communication satellites that will be broadcasting the news of its arrival. The asteroid is about 150 feet in diameter and has a mass estimated at about 143,000 tons.

Should an object of that size hit Earth, it would cause a blast with the energy equivalent of about 2.4 million tons — or 2.4 megatons — of TNT explosives, more than 180 times the power of the atomic blast that leveled Hiroshima.

It’s almost as if nature is firing a shot across our bow to direct our attention to the vast number of nearby rocky asteroids and a few icy comets that make up what we call the near-Earth object population. We should take the warning seriously.

While no known asteroids or comets represent a worrisome impact threat now, NASA’s Jet Propulsion Laboratory shows more than two dozen asteroids have better than a one in a million chance of smacking into Earth within the next 100 years. That may sound reassuring, but we estimate that less than 10 percent of all near-Earth objects have been discovered. And while we are keeping a vigilant eye out for these objects in the Northern Hemisphere, we are considerably less watchful in the Southern Hemisphere.

It has been only within the last 15 years that astronomers, mostly supported by NASA, have begun discovering the vast number of near-Earth objects. Our findings have led us to the realization that Earth runs its course around the sun in a cosmic shooting gallery — with us as the target. Basketball-size rocky objects enter Earth’s atmosphere daily and Volkswagen-size objects every few months, but they burn up before they hit the ground.

Objects larger than about 100 feet in diameter, the size of a large house, strike Earth with an average interval of a few hundred years. The last one of about this size to hit was on June 30, 1908, in a sparsely populated region of Siberia called Tunguska. The Tunguska blast released about four megatons of energy and leveled millions of trees across 825 square miles.

A much larger asteroid or comet, six miles in diameter, collided with Earth some 65 million years ago, killing most of the large vertebrates, including the dinosaurs. Fortunately, Earth collisions with objects so big happen only at average intervals of 100 million years.

What can be done if a rogue asteroid is judged to be on a trajectory that threatens Earth? Our best option would be to send a spacecraft to collide with the asteroid and modify its trajectory to ensure that the Earth is missed by a wide margin. We have the technology to do this — and, in fact, did it in 2005, when we intentionally slammed a spacecraft into the comet Tempel-1. As the science fiction author Larry Niven once said, the dinosaurs became extinct because they didn’t have a space program.

In April 2010, President Obama called upon NASA to send a human mission to an asteroid by 2025 as a steppingstone for the much more difficult human exploration of Mars. The technologies and life support systems needed for the Mars expedition could be tested first at a nearby asteroid with the round trip taking only a few months instead of a few years.

QUITE apart from their menacing reputations or as steppingstones to Mars, near-Earth objects are important in their own right. They are the leftover bits and pieces from the formation of the solar system 4.6 billion years ago, so they provide insights into the original chemical mix and environment of our nascent solar system.

They may also have played a key role in how life arose on Earth. Asteroids and comets most likely brought to the earth much of the water and carbon-based materials that allowed life to form more than 3.5 billion years ago. Subsequent impacts then punctuated evolution, allowing only the most adaptable species to evolve further. Remember the dinosaurs? We mammals may owe our very existence and our position atop the food chain to near-Earth objects.

There are compelling reasons to use these objects as sources of raw materials for the future construction of space habitats and supply depots. They are rich in minerals, metals and platinum-group elements, and their clays and ices could provide water resources. (Within the last year, two United States companies, Planetary Resources and Deep Space Industries, announced plans to mine asteroids for their resources.) The water could be broken down into hydrogen and oxygen, the most efficient form of rocket fuel. Near-Earth objects may serve as the watering holes and fueling stations for interplanetary exploration.

We’ll also need to continue to aggressively discover and track them, if we are to be assured of having a future as a species.

Three NASA-supported observatories with modest telescopes in the southwestern United States and in Hawaii are making more than 95 percent of near-Earth object discoveries. Because of budget limitations, an observatory at Siding Spring, Australia, the only one looking for these objects in the Southern Hemisphere, has reduced its operations to only occasional observations, leaving a blind spot for unknown objects approaching from the southern skies.

Ground-based observatories will always be important as we follow these intriguing objects. But a space-based, wide field-of-view telescope operating in the more sensitive infrared light wavebands is the best way to find the majority of hazardous asteroids within the next decade.

NASA and its domestic and international partners need to be allowed to redouble the search for near-Earth objects with more powerful search telescopes, both ground-based and space-based, so we are not caught off guard. We need to find them before they find us.

 

Donald K. Yeomans is a senior research scientist

and the manager of the Near-Earth Object Program Office

at the Jet Propulsion Laboratory of NASA,

and the author of “Near-Earth Objects:

Finding Them Before They Find Us.”

Beware of Errant Asteroids,
NYT, 9.2.2013,
http://www.nytimes.com/2013/02/10/
opinion/sunday/beware-of-errant-asteroids.html

 

 

 

 

 

Biggest Asteroid in 35 Years

Swings Close to Earth

 

November 8, 2011

The New York Times

By THE ASSOCIATED PRESS

 

LOS ANGELES (AP) — An asteroid as big as an aircraft carrier zipped by Earth on Tuesday in the closest encounter by such a massive space rock in more than three decades. Scientists ruled out any chance of a collision but turned their telescopes skyward to learn more about the object known as 2005 YU55.

Its closest approach to Earth was pegged at a distance of 202,000 miles at 6:28 p.m. EST. That's just inside the moon's orbit; the average distance between Earth and the moon is 239,000 miles.

The last time a large cosmic interloper came that close to Earth was in 1976, and experts say it won't happen again until 2028.

Scientists at NASA's Deep Space Network in the California desert have tracked the quarter-mile-wide asteroid since last week as it approached from the direction of the sun at 29,000 mph.

Astronomers and amateur skygazers around the world kept watch, too.

The Clay Center Observatory in Brookline, Mass., planned an all-night viewing party so children and parents could peer through research-grade telescopes and listen to lectures. The asteroid can't be detected with the naked eye.

For those without a telescope, the observatory streamed video of the flyby live on Ustream, attracting several thousand viewers. The asteroid appeared as a white dot against a backdrop of stars.

"It's a fantastic opportunity to educate the public that there are things out in space that we need to be aware of," including this latest flyby, said observatory director Ron Dantowitz.

Dantowitz added: "It will miss the Earth. We try to mention that in every breath."

If an asteroid that size would hit the planet, Purdue University professor Jay Melosh calculated the consequences. The impact would carve a crater four miles across and 1,700 feet deep. And if it slammed into the ocean, it would trigger 70-foot-high tsunami waves.

Since its discovery six years ago, scientists have been monitoring the spherical, coal-colored asteroid as it slowly spins through space and were confident it posed no danger.

Asteroids are leftovers from the formation of the solar system some 4.5 billion years ago. Scientists believe their growth was stunted by Jupiter's gravitational pull and never had the chance to become full-fledged planets. Pieces of asteroids periodically break off and make fiery plunges through the atmosphere as meteorites.

Don Yeomans, who heads NASA's Near Earth Object Program, said 2005 YU55 is the type of asteroid that humans may want to visit because it contains carbon-based materials and possibly frozen water.

With the space shuttle program retired, the Obama administration wants astronauts to land on an asteroid as a stepping stone to Mars.

"This would be an ideal object," Yeomans said.

___

Online:

NASA's Near-Earth Object Program: http://neo.jpl.nasa.gov

Ustream: http://www.ustream.tv/channel/clay-center-observatory

___

Follow Alicia Chang's coverage at http://www.twitter.com/SciWriAlicia

Biggest Asteroid in 35 Years Swings Close to Earth,
NYT, 8.11.2011,
http://www.nytimes.com/aponline/2011/11/08/
science/AP-US-SCI-Asteroid-Flyby.html - broken link

 

 

 

 

 

NASA’s Second Close Encounter

With a Comet

 

February 13, 2011

The New York Times

By KENNETH CHANG

 

The last time NASA visited the Tempel 1 comet, it was with fireworks, on July 4, 2005. On that day, the Deep Impact spacecraft slammed an 820-pound projectile into Tempel 1, excavating a plume of ice and dust.

On Monday night — Valentine’s Day — NASA will return to Tempel 1 but will not bombard it. This time, a different spacecraft, Stardust, will zip past at more than 24,000 miles per hour, taking 72 high-resolution pictures of the comet’s surface.

Stardust will make its closest approach, within 125 miles, at 11:37 p.m. Eastern time.

Tim Larson, the mission’s project manager, said NASA was not deliberately scheduling its missions to coincide with holidays. “That’s just how the orbital mechanics worked out on these,” he said, “although it makes for great P.R.”

Tempel 1 will be the first comet to be seen at close range twice, and scientists will make a then-and-now comparison — one that they expect will reveal a change in topography and tell them more about the inner workings of comets.

“Here’s a chance where we can see what has changed, how much has changed,” said Joseph Veverka, a professor of astronomy at Cornell and the mission’s principal investigator, “so we’ll start unraveling the history of a comet’s surface."

For example, photographs taken by Deep Impact in 2005 showed areas that looked old and others that seemed much younger. But the snapshots did not tell the ages of any of them. “We have no idea whether we’re talking about things that have been there for a hundred years, a thousand years, a million years,” Dr. Veverka said.

In the five and a half years since Deep Impact’s visit, Tempel 1 — whose orbit brings it as close to the Sun as Mars and as far away as Jupiter — has completed a full orbit.

Stardust was launched in 1999 and arrived five years later at its primary destination, a comet named Wild 2, where it collected particles of dust. Stardust then looped back to Earth and released a canister containing the comet dust, which parachuted back to the ground.

The spacecraft, still operating well, continued onward, and NASA decided to use it for a return visit to Tempel 1. (Deep Impact, meanwhile, also extended its scientific journey, visiting another comet last November.)

One more puzzle that scientists may be able to solve with the second look at Tempel 1 involves depressions that look like the type of craters caused by impacts. The depressions, though, could have been caused by explosions that were a result of underground ice that converted to gas.

The scientists will now be able to compare the depressions with something they know is definitely a crater — the scar left by Deep Impact. “Simple question,” Dr. Veverka said, “direct answer.”

    NASA’s Second Close Encounter With a Comet, NYT, 13.2.2011,
    http://www.nytimes.com/2011/02/14/science/space/14comet.html

 

 

 

 

 

Comet Draws

Scientific, Amateur Interest

 

November 3, 2007
Filed at 12:59 a.m. ET
By THE ASSOCIATED PRESS
The New York Times

 

KNOXVILLE, Tenn. (AP) -- A comet that has unexpectedly brightened in the past couple of weeks and now is visible to the naked eye is attracting professional and amateur interest.

Paul Lewis, director of astronomy outreach at the University of Tennessee, is drawing students to the roof of Nielsen Physics Building for special viewings of Comet 17P/Holmes.

The comet is exploding and its coma, a cloud of gas and dust illuminated by the sun, has grown to be bigger than the planet Jupiter. The comet lacks the tail usually associated with such celestial bodies but can be seen in the northern sky, in the constellation Perseus, as a fuzzy spot of light about as bright as the stars in the Big Dipper.

''This is truly a celestial surprise,'' Lewis said. ''Absolutely amazing.''

Until Oct. 23, the comet had been visible to modern astronomers only with a telescope, but that night it suddenly erupted and expanded.

A similar burst in 1892 led to the comet's discovery by Edwin Holmes.

''This is a once-in-a-lifetime event to witness, along the lines of when Comet Shoemaker-Levy 9 smashed into Jupiter back in 1994,'' Lewis said.

Scientists speculate the comet has exploded because there are sinkholes in its nucleus, giving it a honeycomb-like structure. The collapse exposed comet ice to the sun, which transformed the ice into gas.

''What comets do when they are near the sun is very unpredictable,'' Lewis said. ''We expect to see a coma cloud and a tail, but this is more like an explosion, and we are seeing the bubble of gas and dust as it expands away from the center of the blast.''

Experts aren't sure how long the comet's show will last, but estimate it could be weeks -- if not months. Using a telescope or binoculars help bring the comet's details into view, they said.

------

Information from: The Knoxville News Sentinel, http://www.knoxnews.com 

    Comet Draws Scientific, Amateur Interest, NYT, 3.11.2007,
    http://www.nytimes.com/aponline/us/AP-Brighter-Comet.html

 

 

 

 

 

June 7, 1923

On This Day

 

From The Times archive

What a labourer thought was gunfire
was a rare meteorite

 

THE Natural History Museum at South Kensington has received a very rare and interesting gift in the shape of a meteorite, which fell just before 1pm on March 9 between Saffron Walden and Ashdon, in Essex.

The man who saw the meteorite fall was a labourer, who states that he heard a “sissing” noise and supposed that an aeroplane was overhead. Looking up a second or two after he saw what he thought was a projectile fall about ten to fifteen yards from him, causing the earth to spout up like water.

He was much alarmed, because he considered that something had been discharged from a gun. Three days later, in company with another man, he took the meteorite up from where it had fallen. He says that there was a small hole where it had entered the ground, and this hole increased in width as he dug deeper. The stone was found at a depth of two feet.

The specimen weighs about 3lb, and is what is known as a white chondrite meteoric stone. It is about 5in long by 4in wide and has a thickness of about 3in in its thickest part.

The surface of the stone shows with remarkable distinctness, the lines of flow of fused materials radiated from the centre of the surface and proves that it was partially fused owing to the high velocity at which it entered the earth’s atmosphere.

The rarity of the occurrence of a meteor seen to be falling is evident by the fact that only about fifteen falls have been recorded in the British Islands.

    From The Times Archives > On This Day - June 7, 1923, The Times, 7.6.2005,
    http://www.newsint-archive.co.uk/pages/main.asp

 

 

 

 

 

May 24, 1910

Halley's comet,

seen from a Whit-week train

 

From the Guardian archive

 

Tuesday May 24, 1910

Guardian

 

Halley's comet, writes a correspondent, was very clearly visible last night as I travelled from Crewe to Manchester.

Looking out at the left-hand side of the carriage all the way from Crewe to within a mile or two of Stockport, when the haze swallowed it up, we could see the pale light of it, almost level with the eye below Leo and to the right of Castor and Pollux.

The tail was scarcely visible. A crowded carriage of returning holiday-makers found it a good butt for the a last round of holiday jests.

"Tail fourteen million miles long, has it; shouldn't like to walk it."

"How do they measure it - with a foot rule?"

"Algebra," snapped a man in the corner, and the rest were silent. It was surprising how many seemed to know where to look for it.

Last night the long-looked-for comet was visible at last to us in the north. In Manchester itself the haze which the smoke-stacks of industry gather over the city hid it from view, but out in the country parts of Lancashire and Cheshire the sky was beautiful and clear, and the brilliance of a moon reaching its full was not enough to blot it from sight.

From the rising of the stars it hung there (so those who saw it tell us), just clear of the mists on the fields, pallid and strangely blurred beside the shining definiteness of Castor and Pollux to the right of it and the great constellation of Leo sprawling over its head.

Its unfamiliarity made it easy for the eye to light upon it, but it was very dim and distant, and there was nothing but a faint luminosity about the edge to suggest to the naked eye the tail through which our planet had gone swimming in the past week.

But because its fires glow pale and faint to us here we are not to think that two thousand years (so far we can trace back its appearances in history) have burnt it out. In America and other parts of the globe it has shone with all its former brilliance, accompanied by the same strange bout of terrestrial ecstasy and panic as it had in days gone by.

When the time comes no doubt each country will fit its appearance to their special catastrophes, and in history books centuries after this Frenchmen will read that its coming was heralded by the flooding of their capital, and Englishmen will say that it killed a king.

And last night returning Whit-week travellers peered at it from railway carriage windows and joked about the length of its tail.

From the Guardian archive > May 24, 1910 > Halley's comet,
seen from a Whit-week train, G, Republished 24.5.2006,
http://www.theguardian.com/news/1910/may/24/mainsection.fromthearchive

 

 

 

 

 

 

 

 

 

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