NASA says taking sample from asteroid harder than expected

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This February 27, 2018 photo from NASA’s OSIRIS-REx spacecraft, obtained March 18, 2019 courtesy of NASA/Goddard/University of Arizona, shows a close up of the asteroid Bennu from a distance of 0.8 miles (1.3 km). (AFP)
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This December 2, 2018 photo from NASA’s OSIRIS-REx spacecraft, obtained March 18, 2019 courtesy of NASA/Goddard/University of Arizona, shows a mosaic image of asteroid Bennu, composed of 12 PolyCam images, from a distance of 12 miles (124 km). (AFP)
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This artist's rendering made available by NASA in July 2016 shows the mapping of the near-Earth asteroid Bennu by the OSIRIS-REx spacecraft. (AP)
Updated 20 March 2019
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NASA says taking sample from asteroid harder than expected

  • The asteroid, which orbits the sun, is 85 million kilometers (52 million miles) from the Earth
  • The samples will be stowed in the probe, which will return to Earth in 2023

WASHINGTON: After two years crossing the solar system, the NASA space probe Osiris-Rex arrived last December near the asteroid Bennu to complete its mission of collecting a sample — but touching the rock will prove much harder than scientists had expected.
The Osiris-Rex team said Tuesday that the surface of the asteroid, which measures 490 meters (1,600 feet) in diameter, was covered in stones and boulders. They had expected it to be smoother and easier for the probe to touch.
“We go back to the drawing board and start thinking again,” Dante Lauretta, the head of the mission, told a press conference. The team’s observations also appeared in the Nature journal on Tuesday.
The probe was designed to head for a flat area with a radius of 25 meters, but the images beamed back since December showed that there is no area that big which is free of boulders.
As a result, the team will have to aim more tightly.
“Now we’re going to try to hit the center of the bullseye,” said project manager Richard Burns.
Since December, the probe has been using its instruments to map Bennu from a close distance, currently three miles.
The asteroid, which orbits the sun, is 85 million kilometers (52 million miles) from the Earth.
The goal is touch the surface with a robotic arm for just five seconds in July 2020, retrieving a sample of between 60 grams and two kilograms (two ounces to 4.4 pounds) of regolith, which means relatively small particles such as gravel or sand, since the machine can only suck up particles measuring less than two centimeters.
The samples will be stowed in the probe, which will return to Earth in 2023.
Bennu is technically known as “rubble-pile asteroid,” that is, it is made up of pieces of debris that had broken off larger celestial bodies and come together under the effect of gravity.
It has more than 200 boulders larger than 10 meters in diameter, and some stretching up to 30 meters, according to researchers writing in Nature Astronomy. It has a number of craters between 10 and over 150 meters in length.
“It is not trivial to deliver a spacecraft with meter scale resolution to the surface of an asteroid in the microgravity environment,” said Lauretta, who nevertheless said he was “confident” that the team would rise to the challenge.
Another surprise Bennu had been withholding was that it emits particles which fall back to the surface like rain. That should not however endanger the probe, the team said.


‘Stronger than ever’: India set for fresh Moon launch attempt

Updated 21 July 2019
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‘Stronger than ever’: India set for fresh Moon launch attempt

  • The South Asian nation is bidding to become just the fourth nation to land a spacecraft on the Moon
  • The first launch attempt was scrubbed just under an hour before the scheduled lift-off because of what authorities described as a “technical snag”

SRIHARIKOTA, India: India will make a second attempt Monday to send a landmark spacecraft to the Moon after an apparent fuel leak forced last week’s launch to be aborted.
The South Asian nation is bidding to become just the fourth nation — after Russia, the United States and China — to land a spacecraft on the Moon.
The mission comes 50 years after Neil Armstrong became the first person to step foot on the moon, an occasion celebrated by space enthusiasts globally on Saturday
The fresh launch attempt for Chandrayaan-2 — Moon Chariot 2 in some Indian languages including Sanskrit and Hindi — has been scheduled for 2:43 p.m. (0913 GMT) on Monday, the Indian Space Research Organization (ISRO) said.
“Chandrayaan 2 is ready to take a billion dreams to the Moon — now stronger than ever before!” it said on Thursday.
The first launch attempt was scrubbed just under an hour before the scheduled lift-off because of what authorities described as a “technical snag.” Local media, citing ISRO officials, said that issue was a fuel leak.
The agency tweeted Saturday that a rehearsal for the launch was completed successfully.
Chandrayaan-2 will be launched atop a Geosynchronous Satellite Launch Vehicle (GSLV) MkIII, India’s most powerful rocket.
Experts said setbacks were to be expected in such missions given their complexity, and that it was more prudent to delay the launch instead of taking risks that may jeopardize the project.
“In such an ambitious and prestigious mission like Chandrayaan, one cannot take a chance even if a small flaw is detected,” Rajeswari Pillai Rajagopalan, head of space policy at the New Delhi think tank the Observer Research Foundation, told AFP.
Former NASA scientist Kumar Krishen said India’s space agency should be praised for taking on ambitious projects like Chandrayaan-2.
“We should keep in mind that space exploration is risky as many systems have failed in the past and many lives lost,” he told AFP.
Aside from propelling India into rarefied company among spacefaring nations, Chandrayaan-2 also stands out because of its low cost.
About $140 million has been spent on preparations for the mission, a much smaller price tag compared with similar missions by other countries — whose costs often run into billions of dollars.
Chandrayaan-2, and India’s space program as a whole, are a source of national pride in India.
Prime Minister Narendra Modi has outlined an ambitious plan to launch a crewed space mission by 2022, and India hopes to seek out commercial satellite and orbiting deals.
The new mission comes almost 11 years after the launch of India’s first lunar mission — Chandrayaan-1 — which orbited the Moon and searched for water.
The rocket carrying Chandrayaan-2 will launch from the Satish Dhawan Space Center at Sriharikota, an island off the coast of the southern state of Andhra Pradesh.
The spacecraft will carry an orbiter, lander and a rover, which has been almost entirely designed and made in India.
The orbiter is planned to circle the Moon for about one year, imaging the surface and studying the atmosphere.
The lander, named Vikram, will head to the surface near the lunar South Pole carrying the rover. Once it touches down, the rover will carry out experiments while being controlled remotely by ISRO scientists.
It is expected to work for one lunar day, the equivalent of 14 Earth days, and will look for signs of water and “a fossil record of the early solar system.”