Asteroid makes ‘flyby’ Thursday

AFP, katasztrofak.abbcenter.com and National Historical Commission of the Philippines

A heavenly body packing more energy than 25,000 Hiroshima bombs and which can obliterate Luzon on impact will streak across the skies near Earth on Thursday under the watchful gaze of astronomers the world over.

Scientists will be tracking the path of the asteroid called 99942 Apophis as it comes within 14.5 million kilometers of the Earth’s surface, a distance not visible to the naked eye, but can be seen through a powerful telescope, the country’s chief astronomer said.

“It will appear like a tiny star flying quickly by,” said Dario de la Cruz, head of the space sciences and astronomy section of the Philippine Atmospheric, Geophysical and Astronomical Services Administration (Pagasa).

The flyby of Apophis, named after the Egyptian god of darkness, affords astronomers an opportunity to monitor the asteroid’s path and recalculate its odds of ramming the planet when it whizzes by again, at a much closer distance, in 16 years’ time, scientists said.

Closer to earth in ’29

On April 13, 2029, it will fly much closer to Earth at 29,470 km, closer even than the orbit of man-made satellites, according to scientists from Jet Propulsion Laboratory (JPL) of the US National Aeronautics and Space Administration (Nasa).

There’s also a tiny chance that when the asteroid passes in 2029, the Earth’s gravity may nudge it from its orbit if it passes through what scientists call a “gravitational keyhole,” such that it may collide with Earth when it comes by again in 2036.

While Nasa and other space agencies are busy observing Apophis’ movement, Pagasa won’t be. “We don’t have the capability to track the asteroids. We will have to rely on other space agencies,” De la Cruz said.

At 270 meters in diameter and based on its projected velocity, the heavenly body will deliver more energy than 25,000 Hiroshima bombs if it smashes into Earth, enough to “turn the entire Luzon into dust,” said Jose Mendoza IV, chief of Pagasa’s astronomical publication unit.

The asteroid “will be moving faster than ordinary satellites,” so stargazers will have to keep their telescope ready when it whizzes by, guided by coordinates provided by international space agencies, he said.

Mendoza said Pagasa did not have the state-of-the-art tracking technology needed to observe cosmic rocks like Apophis, but he encouraged astronomy enthusiasts to do their own research.

When it was first discovered in 2004, Apophis’ chance of hitting the Earth was estimated at a startling 2.7 percent but later calculations based on newer information helped lower this to practically nil.

 

Second asteroid

Pagasa is also monitoring—through available data—a small asteroid named 2012 DA14.

Citing Nasa information, Mendoza said the asteroid would pass by Earth at a distance of 24,000 km on Feb. 13.

“Satellites go higher than that. We also continue to monitor DA14 and we are also getting information from Nasa offices,” he  said in an earlier Inquirer interview.

Nasa earlier said DA14 would pass inside the geosynchronous satellite ring, located about 35,800 km above the equator, and “travel rapidly from the southern evening sky into the northern morning sky with its closest Earth approach occurring about 19:26 UTC [coordinated universal time].”

But even if it does hit Earth, DA14 “will cause nominal damage.”

Unlike Apophis, DA14—discovered by La Sagra Observatory in Southern Spain—is considered tiny at just 40 m to 45 m in diameter.

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