NASA’s Interior Exploration using Seismic Investigations, Geodesy and Heat Transport (InSight) mission to study the deep interior of Mars is targeting a new launch window that begins May 5, 2018, with a Mars landing scheduled for Nov. 26, 2018. InSight’s primary goal is to help us understand how rocky planets — including Earth — formed and…
Astronauts went spacewalking Friday to provide some necessary focus to the International Space Station’s robot arm.
The main job for commander Randy Bresnik and teacher-turned-astronaut Joe Acaba was to replace a blurry camera on the new robotic hand that was installed during a spacewalk two weeks ago. The two men were supposed to go spacewalking earlier this week, but NASA needed extra time to rustle up the repair plan.
Sharp focus is essential in order for the space station’s robot hand to capture an arriving supply ship. The next delivery is a few weeks away, prompting the quick camera swap-out.
Orbital ATK, one of NASA’s commercial shippers, plans to launch a cargo ship from Virginia on November 11.
Acaba was barely outside an hour when he had to replace one of his safety tethers, which keep him secured to the orbiting outpost and prevent him from floating away.
Mission Control noticed his red tether seemed frayed and worn and ordered Acaba to “remain put” with his good waist tether locked to the structure as Bresnik went to get him a spare.
Spacewalking astronauts always have more than one of these crucial lifelines in case one breaks. They also wear a jetpack in case all tethers fail and they need to fly back to the space station.
This was the third spacewalk in two weeks for the space station’s U.S. residents. Bresnik performed the first two with Mark Vande Hei.
As they ventured out, Bresnik noted they were flying over Puerto Rico.
“Get out of here,” replied Acaba, the first astronaut of Puerto Rican heritage.
Acaba’s parents were born there, and he still has family on the hurricane-ravaged island.
“There’s a whole line of people looking up and smiling today as you get ready to head out the door,” Bresnik said.
Friday’s spacewalk should be the last one for the year. Early next year, astronauts will replace the hand on the opposite side of the 58-foot robot arm, Canada’s main contribution to the space station. The original latching mechanisms are showing wear and tear since the arm’s launch in 2001.
The 250-mile-high complex is currently home to three Americans, two Russians and one Italian.(VOA)
Washington, Oct 20: NASA has approved a second extension of the Dawn mission at Ceres, the largest object in the asteroid belt between Mars and Jupiter.
During this extension, the spacecraft will descend to lower altitudes than ever before at the dwarf planet, which it has been orbiting since March 2015, the US space agency said on Thursday.
The spacecraft, which has already completed 10 years of spaceflight, will continue at Ceres for the remainder of its science investigation and will remain in a stable orbit indefinitely after its fuel runs out.
Dawn completed its prime mission in June 2016, and its first extension was also approved that year.
The Dawn flight team is studying ways to manoeuvre Dawn into a new elliptical orbit, which may take the spacecraft to less than 200 kilometres from the surface of Ceres at closest approach. Previously, Dawn’s lowest altitude was 385 kilometers.
A priority of the second Ceres mission extension is collecting data with Dawn’s gamma ray and neutron spectrometer, which measures the number and energy of gamma rays and neutrons, NASA said.
This information is important for understanding the composition of Ceres’ uppermost layer and how much ice it contains.
The spacecraft also will take visible-light images of Ceres’ surface geology with its camera, as well as measurements of Ceres’ mineralogy with its visible and infrared mapping spectrometer.
The extended mission at Ceres additionally allows Dawn to be in orbit while the dwarf planet goes through perihelion, its closest approach to the Sun, which will occur in April 2018.
Because of its commitment to protect Ceres from Earthly contamination, Dawn will not land or crash into Ceres.
Instead, it will carry out as much science as it can in its final planned orbit, where it will stay even after it can no longer communicate with Earth.
Mission planners estimate the spacecraft can continue operating until the second half of 2018.
Dawn is the only mission ever to orbit two extraterrestrial targets. It orbited giant asteroid Vesta for 14 months from 2011 to 2012, then continued on to Ceres, where it has been in orbit since March 2015.(IANS)
New York, Oct 13: Astronomers have discovered that a Sun-like star lurking around 350 light-years away consumed the rocky equivalent of 15 Earths.
Dubbed Kronos after the child-eating Titan of Greek mythology, the star is the clearest and most dramatic case yet of a Sun-like star consuming its own planets, said Semyeong Oh, astrophysicist at Princeton University in New Jersey and lead author of the study.
“Even if our Sun ate the entire inner solar system, it wouldn’t come close to the anomaly we see in this star,” study co-author David Hogg from the Flatiron Institute in New York added.
The research did not begin as a hunt for a planet-eater.
Oh was analysing a catalog of new star data collected by the European Space Agency’s Gaia spacecraft for pairs of stars with similar speeds and trajectories.
Such duos are typically twin stars that formed close together from the same ingredients.
The analysis ultimately led to the identification of Kronos and its lesser known brother Krios.
Their official designations are HD 240430 and HD 240429, and they are both about 350 light years from Earth.
The keys to the discovery were first confirming that the widely separated pair are in fact a binary pair, and secondly observing Kronos’ strikingly unusual chemical abundance pattern, Oh explained in a statement released by the Princeton University.
Other co-moving star pairs have had different chemistries, Oh explained, but none as dramatic as Kronos and Krios.
Most stars that are as metal-rich as Kronos “have all the other elements enhanced at a similar level,” she said, “whereas Kronos has volatile elements suppressed, which makes it really weird in the general context of stellar abundance patterns.”
In other words, Kronos had an unusually high level of rock-forming minerals, including magnesium, aluminium, silicon, iron, chromium and yttrium, without an equally high level of volatile compounds — those that are most often found in gas form, like oxygen, carbon, nitrogen and potassium, the study said. (IANS)