An asteroid the size of the Eiffel Tower will pass through Earth on Friday, March 5 and will be out of our planetary quarter until 2029.
The space rock, called Apophis (an ancient Egyptian demon), was first seen in 2004 and will pose no danger to Earth during this week’s flyby; it will travel beyond the planet more than 40 times the distance from Earth to the moon.
But scientists are using this week as a general test for the asteroid’s next step, April 13, 2029, when Apophis will approach Earth as some of the satellites with the highest orbit.
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“Apophis in 2029 will be a truly amazing observation opportunity for us,” Marina Brozović, a radar scientist at NASA’s Jet Propulsion Laboratory in California, told Live Science’s sister site Space.com. “But before we get to 2029, we’re getting ready.”
A brief overflight
Apophis is 340 meters wide and made of rock, iron and nickel. It is probably about the shape of a peanut, although astronomers will have a better idea of its shape when they pass through Earth this week, according to NASA.
The asteroid makes a complete orbit around the sun about every 11 months. On March 5 it will reach less than 150 million kilometers from Earth at 8:15 pm EST (0115 GMT on March 6).
This is too far away to see with the naked eye, but scientists will use planetary radar to imagine Apophis as it flies using NASA’s Goldstone Deep Space Communications Complex in California and the Green Bank Telescope in West Virginia. They hope to determine the shape of the asteroid and learn more about how it rotates.
“We know that Apophis is in a very complicated state of spin, it’s spinning and falling at the same time,” Richard Binzel, a planetary scientist at the Massachusetts Institute of Technology, told Space.com.
Approaching
This study of planetary radar will provide researchers with a baseline for a flight much closer to 2029, when Apophis will approach 31,900 kilometers from Earth.
This is close enough that the Earth’s gravity can change the shape of the asteroid or scatter rock blocks across its surface. Binzel, as and if he changes the asteroid as it passes, will help reveal details about the asteroid’s inner structure.
At the closest time to 2029, Apophis will be briefly visible to the naked eye in Western Australia and will grow as bright as the stars of the Big Dipper.
It will be closest to Earth at 6:00 pm EDT on April 13, 2029, when it will be over the Atlantic, an ocean that will cross in just one hour. The asteroid will cross the United States at 19:00 EDT.
Apophis is named after an ancient Egyptian demon who personified chaos and evil, mainly because astronomers initially calculated that there was a 3% chance that the asteroid could impact Earth in its 2029 overflight.
They have now shown that the asteroid will not collide with Earth in 2029 nor in its next step in 2036.
There is still a small chance that the asteroid could hit Earth in 2068, but the 2021 and 2029 flybys should provide astronomers with more information to calculate the future of Apophis.
This article was originally published by Live Science. Read the original article here.