Astronauts to patch up NASA’s NICER telescope

NASA is planning to restore NICER (Neutron star Inside Composition Explorer), an X-ray telescope on the Worldwide Area Station, throughout a spacewalk later this 12 months. Will probably be the fourth science observatory in orbit serviced by astronauts.

In Could 2023, scientists discovered that NICER had developed a “mild leak.” Undesirable daylight was coming into the instrument and reaching the telescope’s delicate detectors. Whereas the workforce took instant steps to mitigate the affect on observations, in addition they started fascinated about a possible restore.

“The daylight interferes with NICER’s capacity to gather viable X-ray measurements throughout the station’s daytime,” stated Zaven Arzoumanian, NICER’s science lead at NASA’s Goddard Area Flight Middle in Greenbelt, Maryland. “Nighttime observations are unaffected, and the telescope continues to supply unbelievable science. Lots of of printed papers have used NICER for the reason that mission started. Blocking among the mild leaking in would permit us to return to extra regular operations across the clock.”

Arzoumanian offered efforts to deal with the problem throughout a chat on Friday, April 12, on the twenty first assembly of the Excessive Power Astrophysics Division of the American Astronomical Society in Horseshoe Bay, Texas.

NICER is positioned close to the station’s interior starboard solar panels. From that perch, it appears out on the X-ray sky, accumulating information on many cosmic phenomena, like common pulses from superdense stellar remnants referred to as neutron stars and “mild echoes” from flaring black holes.

Observing these objects helps reply questions on their nature and habits and will increase our understanding of matter and gravity. In 2017, NICER additionally demonstrated using pulsing neutron stars in our galaxy to function navigational beacons for future deep space exploration by way of a program referred to as SEXTANT (Station Explorer for X-ray Timing and Navigation Expertise).

The telescope has 56 aluminum X-ray concentrators. Every concentrator has a set of nested mirrors, designed to skip X-rays right into a detector. In entrance of the concentrator lies a skinny filter, referred to as a thermal defend, that blocks out daylight. The concentrator is topped by a hole round piece of carbon composite, referred to as a sunshade, with six segments that resemble a sliced pie. The sunshade is designed to maintain the concentrators cool in daylight and defend the fragile thermal shields. After the sunshine leak developed, photographs revealed a number of small areas of injury in among the shields, although what triggered them remains to be unclear.

“We did not design NICER for mission servicing. It was put in robotically, and we function it from the bottom,” stated Keith Gendreau, NICER’s principal investigator at Goddard. “The opportunity of a restore has been an thrilling problem. We thought of each spacewalk and robotic options, puzzling out tips on how to set up patches utilizing what’s already current on the telescope and in space station toolkits.”

After many months of consideration, the spacewalk was chosen as the trail ahead. NASA’s Hubble Area Telescope and Photo voltaic Most Mission, in addition to AMS (Alpha Magnetic Spectrometer, additionally on the station), are the one different science observatories repaired by astronauts in orbit.

NICER’s answer is simple. 5 pie-piece-shaped wedges will slot into the sunshades above the areas with the best injury and lock into place. The patches are designed to make the most of an current piece of astronaut gear referred to as a T-handle device.

“Whereas we labored laborious to make sure the patches are mechanically easy, most restore actions in space are very sophisticated,” stated Steve Kenyon, NICER’s mechanical lead at Goddard. “We have been conducting assessments to substantiate the restore work might be each an efficient repair for NICER’s mild leak and fully secure for the astronauts on the spacewalk and the space station.”

The patches are at present scheduled to launch to the space station aboard Northrop Grumman’s twenty first business resupply providers mission later this 12 months. Astronauts will full their set up throughout a spacewalk, together with different duties.

NICER is an Astrophysics Mission of Alternative inside NASA’s Explorers Program, which gives frequent flight alternatives for world-class scientific investigations from space using revolutionary, streamlined, and environment friendly administration approaches inside the heliophysics and astrophysics science areas. NASA’s Area Expertise Mission Directorate helps the SEXTANT element of the mission, demonstrating pulsar-based spacecraft navigation.

NICER additionally collaborates in automated tandem with JAXA’s (Japan Aerospace Exploration Company’s) experiment MAXI (Monitor of All-sky X-ray Picture) to quickly observe stars and different objects that flare unpredictably, advancing scientific understanding of our dynamic universe.