[vox_mundi]

Will asteroid 2012 TC4 hit Earth in October 2017?

On Oct. 12, 2017, the asteroid 2012 TC4 is slated to whizz by Earth dangerously close. The exact distance of its closest approach is uncertain, as well as its size. Based on observations in October 2012 when the space rock missed our planet, astronomers estimate that its size could vary from 12 to 40 meters. The meteor that exploded over the Russian city of Chelyabinsk in February 2013, injuring 1,500 people and damaging over 7,000 buildings, was about 20 meters wide. Thus, the impact of 2012 TC4 could be even more devastating. "It is something to keep an eye on," Judit Györgyey-Ries, astronomer at the University of Texas' McDonald Observatory, told astrowatch.net. "We could see an airburst maybe broken windows, depending on where it hits."

The fact that the MOID [minimum orbit intersection distance] is only 0.079 LD (Lunar Distance) flags it as a possible impactor (18,800 miles - within GeoSync orbit). Error bars intersect the planet. "The size was estimated from the brightness, but we don't know the reflectivity. So it could be smaller or larger, assume from 10 m to 40 m. A 40 m iron object would go through the atmosphere and make a crater; a 10 m rocky object would be hardly noticed."

[Tanada]

Updated info,

On Oct. 12, 2017, the asteroid 2012 TC4 is scheduled to whizz by Earth seriously close. The precise distance of its closest approach is still unclear, as well as its size. Based on observations in October 2012 when the asteroid 2012 TC4 missed our planet, astronomers guess that its size could differ from 12 to 40 meters. The meteor that blowup over the Russian city of Chelyabinsk in February 2013, injuring 1,500 people and seriously damaging over 7,000 buildings, was nearly 20 meters wide. Thus, the impact of 2012 TC4 could be even more overwhelming. Judit Györgyey-Ries, astronomer at the University of Texas' McDonald Observatory, spoke to astrowatch.net. "It is something to keep an eye on. We could see an airburst maybe broken windows, depending on where it hits." The house-sized asteroid was discovered on Oct. 4, 2012 by the Pan-STARRS observatory located in Hawaii. Week later, it gave Earth a close cut when it passed the planet at the distance of 0.247 LD (lunar distance), or 94,800 km. Asteroid 2012 TC4 is a stretched and rapidly spinning object and has been known to make many close approaches to Planet Earth in the past. Now, the researchers try to conclude the precise path of 2017 fly-by and the possibility of a potential impact.

Györgyey-Ries said "It has a 0.00055% cumulative chance that it will hit. The fact that the MOID [minimum orbit intersection distance] is only 0.079 LD flags it as a possible impactor. However it is just the smallest possible distance between the orbits." Detlef Koschny, director of the Near-Earth Object (NEO) Segment in the Space Situational Awareness (SSA) program office at ESA, told astrowatch.net. "There is one in a million chance that it could hit us," He also tried to evaluate the precise size of the celestial body. He said "The size was estimated from the brightness, but we don't know the reflectivity. So it could be smaller or larger, assume from 10 m to 40 m. A 40 m iron object would go through the atmosphere and make a crater; a 10 m rocky object would be hardly noticed."

Makoto Yoshikawa of the Japanese Aerospace Exploration Agency (JAXA), affiliate of NEOs Division at the International Astronomical Union (IAU) believe that the asteroid poses no threat to Earth. He said "The distance is very small. But this distance does not mean the collision," NASA's Asteroid Watch has guaranteed there is no chance this asteroid will touch our planet, but Györgyey-Ries confesses that more observations are required to ease the doubts.

As of Apr. 12, 2015, there are 1572 possibly hazardous asteroids (PHA) spotted. None of the known PHAs is on a collision path with our planet, although astronomers are discovering new ones all the time.

http://www.physics-astronomy.com/2015/0 ... th-in.html

[vox_mundi]

2012 TC4 - Earth Impact Risk Summary and http://neo.jpl.nasa.gov/risk/

Vimpact = 12.91 km/s
Mass = 4.9e+06 kg
Energy = 9.7e-02 MT

9.7e-02 = 0.097 MT = 97 kilotons (6-7 x Hiroshima)

ImpactEarth - Asteroid Impact Calculator

[Cog]

No

[dolanbaker]

This one whizzed by today, less than 0.3 the distance of the moon away and it was about the size of a house.
http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2015%20TC25&orb=1

[Subjectivist]

2012 TC4 - Earth Impact Risk Summary and http://neo.jpl.nasa.gov/risk/

Vimpact = 12.91 km/s
Mass = 4.9e+06 kg
Energy = 9.7e-02 MT

9.7e-02 = 0.097 MT = 97 kilotons (6-7 x Hiroshima)

ImpactEarth - Asteroid Impact Calculator

Let's see 75 percent chance it will hit water or deep ice like Antarctica. If it hits the land area, another 20 percent is farm, forest or desert with very few people. Even if it hit NYC or London the blast would kill a few thousand extremely unlucky folks who happened to be in the wrong place at the wrong time.

[vox_mundi]

NASA just announced an unexpected asteroid flyby this Halloween

It’s time to get to know a new friend: asteroid 2015 TB145, a sizeable chunk of rock that’s hurtling through space at speeds of over 126,000 km/h (78,293 mph) right now. Discovered just 10 days ago, the asteroid has caught the attention of scientists at NASA because on October 31, it’s expected to draw closer to Earth than anything this size has since July 2006.

Asteroid 2015 TB145 is estimated to be between 280 to 620 metres (918 to 2,034 ft) in diameter.

NASA says asteroid 2015 TB145 has an extremely eccentric and high-inclination orbit, which Colin Jeffrey at Gizmag suggests could be the reason it was only just recently discovered (which is admittedly a bit disconcerting).

Scientists find link between comet and asteroid showers and mass extinctions

Mass extinctions occurring over the past 260 million years were likely caused by comet and asteroid showers, scientists conclude in a new study published in Monthly Notices of the Royal Astronomical Society.

For more than 30 years, scientists have argued about a controversial hypothesis relating to periodic mass extinctions and impact craters—caused by comet and asteroid showers—on Earth.

In their MNRAS paper, Michael Rampino, a New York University geologist, and Ken Caldeira, a scientist in the Carnegie Institution's Department of Global Ecology, offer new support linking the age of these craters with recurring mass extinctions of life, including the demise of dinosaurs. Specifically, they show a cyclical pattern over the studied period, with both impact craters and extinction events taking place every 26 million years.

This cycle has been linked to periodic motion of the sun and planets through the dense mid-plane of our galaxy. Scientists have theorized that gravitational perturbations of the distant Oort comet cloud that surrounds the sun lead to periodic comet showers in the inner solar system, where some comets strike the Earth.

To test their hypothesis, Rampino and Caldeira performed time-series analyses of impacts and extinctions using newly available data offering more accurate age estimates.

"The correlation between the formation of these impacts and extinction events over the past 260 million years is striking and suggests a cause-and-effect relationship," says Rampino.

Specifically, he and Caldeira found that six mass extinctions of life during the studied period correlate with times of enhanced impact cratering on Earth. One of the craters considered in the study is the large (180 km diameter) Chicxulub impact structure in the Yucatan, which dates at about 65 million years ago—the time of a great mass extinction that included the dinosaurs.

Moreover, they add, five out of the six largest impact craters of the last 260 million years on earth correlate with mass extinction events.

"This cosmic cycle of death and destruction has without a doubt affected the history of life on our planet," Rampino observes.

[Outcast_Searcher]

NASA just announced an unexpected asteroid flyby this Halloween

It’s time to get to know a new friend: asteroid 2015 TB145, a sizeable chunk of rock that’s hurtling through space at speeds of over 126,000 km/h (78,293 mph) right now. Discovered just 10 days ago, the asteroid has caught the attention of scientists at NASA because on October 31, it’s expected to draw closer to Earth than anything this size has since July 2006.

Asteroid 2015 TB145 is estimated to be between 280 to 620 metres (918 to 2,034 ft) in diameter.

NASA says asteroid 2015 TB145 has an extremely eccentric and high-inclination orbit, which Colin Jeffrey at Gizmag suggests could be the reason it was only just recently discovered (which is admittedly a bit disconcerting).

Scientists find link between comet and asteroid showers and mass extinctions

Mass extinctions occurring over the past 260 million years were likely caused by comet and asteroid showers, scientists conclude in a new study published in Monthly Notices of the Royal Astronomical Society.

Ah, more random panic mongering from Vox.

I see what you did there. Failing to mention the huge margin of miss in the projection. Let me fix that for you.

Since Ebola didn't kill us, why not try random posts about an asteroid or comet projected to miss earth by about 1.3 times the distance from the earth to the moon? (gasp) And also point out that this kind of fairly common event hasn't happened in almost a decade? (gasp gasp)

http://www.space.com/30902-spooky-hallo ... comet.html

The big asteroid that will zoom past Earth on Halloween may actually be a comet, NASA researchers say.

The roughly 1,300-foot-wide (400 meters) asteroid 2015 TB145, which some astronomers have dubbed "Spooky," will cruise within 300,000 miles (480,000 kilometers) of Earth on Halloween (Oct. 31) — just 1.3 times the average distance between our planet and the moon.

Must be a slow new day in doom land.

Too much recent positive economic news, I guess, which of course the doomers hate to mention.

[vox_mundi]

Very good Outcast_Searcher, it's only taken you 4 days to read 500 words. You're making progress.

Carry-on with what you were doing.