There have been conflicting reports and agitated internet chatter about near-Earth Asteroid TX68 passing by Earth on March 7 (but time uncertainty is still 2 days). Now scientists are saying it could brush by Earth at a distance close enough to threaten orbiting satellites!
Uncertainty Surrounds Asteroid Near-Earth Flyby Next Week
A decent-size asteroid will zoom past Earth next week, but astronomers aren't sure exactly when the flyby will happen, or just how close the space rock is going to get.
The latest observations suggest that the 100-foot-wide (30 meters) near-Earth asteroid 2013 TX68 will come within about 3 million miles (5 million kilometers) of Earth's surface on March 8, NASA researchers said. But it's also possible that the space rock will get much, much closer — 15,000 miles (24,000 km) or so, which is inside the planet's ring of geostationary satellites.
2013 TX68 was discovered in October 2013 by astronomers working with the Catalina Sky Survey in Arizona. The asteroid orbits the sun every 780 days or so; two years ago, 2013 TX68 flew by Earth at a distance of 1.3 million miles (2 million km).
However, observations of the asteroid remain limited, which explains the uncertainty associated with its orbit.
2013 TX68 isn't particularly big as far as space rocks go, and it wouldn't do serious, widespread damage if it did hit Earth. (Most researchers think asteroids must be at least 0.6 miles, or 1 km, wide to cause problems for humanity on a global scale.)
But a collision between 2013 TX68 and Earth would be dramatic: The asteroid would probably explode above Earth's surface in an airburst twice as powerful as the 2013 Chelyabinsk event, which damaged buildings and injured more than 1,200 people in the Russian city of Chelyabinsk, NASA officials said.
Scientists think the Chelyabinsk airburst was caused by a near-Earth object about 65 feet (20 m) wide. - Full story on Space.com
No need to panic: 100ft asteroid predicted for close brush with Earth
Scientists are urging people not to panic after learning a 100ft-wide asteroid could be about to brush by the Earth at a distance close enough to threaten orbiting satellites.
The space rock, named 2013 TX68, is expected to make its nearest approach to Earth early this month.
But the precise timing of its visit and trajectory will not be known until after the event.
The asteroid could shoot past the Earth inside the ring of communications and GPS satellites located in fixed positions 36,000km miles above the equator, say experts.
At the other limit of its predicted path range it could remain as far out as 40 times the distance to the moon.
US scientist Sean Marshall, from Cornell University in New York, who studies near-Earth objects (NEOs) such as comets and asteroids said: "Should this asteroid come closer than the geostationary satellites, it would be a rare occurrence - that only happens about once per decade for large asteroids. What we know for sure is that it will not collide with Earth this month, so do not panic."
He added: "The large uncertainty in TX68's orbit makes it difficult to plan observations in advance, but hopefully it will be seen by some of the automated asteroid survey telescopes.
"However, it is possible that TX68 will be so far from Earth that it will be too faint to be seen. If TX68 is detected this month, that would greatly reduce the uncertainty in its orbit and allow astronomers to calculate its future trajectory much more accurately."
Geostationary satellites are further away than the International Space Station, which orbits at 400km above Earth. - Independent
From EarthSky:
Uncertainties, still, for asteroid 2013 TX68
Asteroid 2013 TX68 passes closest in early March. Astronomers know it will pass safely, but its precise distance at its closest still is unknown.
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| Expected position in the sky of asteroid 2013 TX68 as of March 1, 2016, about 30 minutes after sunset. The space rock will be difficult to observe even with telescopes, especially if the asteroid passes at a great distance. At present, its distance at closest approach is not known. Illustration by Eddie Irizarry using Stellarium. |
Asteroid 2013 TX68 may pass by Earth around the evening of March 7 (according to clocks in the Eastern Time zone), but the time uncertainty is still 2 days. That means the space rock may be passing by our planet sometime between the evenings of March 5 and 9. The asteroid is travelling at a speed of 34,279 miles per hour (55,166 km/h).
Why is there so much uncertainty about this object?
It’s the scenario that astronomers have always cautioned us about … the fact that asteroid 2013 TX68 is approaching Earth from the sun’s direction. In late February, the space rock was still approaching Earth from this direction, although the asteroid was actually at a greater distance from us than our star. In other words, it has been in the daytime sky, and astronomers can’t observe it.
The uncertainty of the exact date of closest approach as well as the precise orbit, is due to the fact that asteroid 2013 TX68 was just observed during 10 days (including the newly found pre-discovery images). That is still a short time to define an orbit precisely. After it was observed and tracked for those few days in 2013, the asteroid passed into Earth’s daytime sky and could no longer be observed.
