HELSINKI — Japan sent a brand new X-ray space telescope into low Earth orbit and a primary, small lunar lander on its option to the moon with a single launch late Wednesday.
A Mitsubishi Heavy Industries H-2A rocket in a figuration with a pair of SRB-A3 solid boosters lifted off from Japan’s Tanegashima Space Center at 7:42 p.m. Eastern, Sept. 6, heading East over the Pacific Ocean. A previous launch attempt was scrubbed Aug. 27.
The rocket carried inside its 4-meter-diameter fairing the Smart Lander for Investigating Moon (SLIM) for the Japan Aerospace Exploration Agency (JAXA), and XRISM, a joint JAXA/NASA X-ray observatory with participation from the European Space Agency.
XRISM separated from the second stage 14 minutes after liftoff, entering a roughly 550 x 500-kilometer orbit inclined by 31 degrees. The second stage performed an apogee-raising burn around 46 minutes after liftoff, with SLIM separating from the stage a minute later.
SLIM won’t be taking a direct path to the moon. After a lunar transfer orbit burn, it should make a lunar flyby, heading right into a wide loop away from the Earth-moon system and returning to enter lunar orbit in around 4 months’ time. This route allows for a smaller burn to enter lunar orbit, saving propellant and mass.
SLIM will then orbit the moon for around a month before making its 20-minute descent and landing attempt, with the aim of demonstrating a light-weight landing capability with high accuracy.
XRISM is a substitute for Japan’s Hitomi space science observatory, which was lost following an attitude control failure a month after its launch in 2016, leading to the spacecraft breaking apart.
The eight meters long, three-meter-diameter and a pair of,300-kilogram spacecraft carries a soft X-ray spectrometer and soft X-ray imager. The telescope will spend three years collecting high spectral resolution data of hot plasma clouds enveloping galaxies and very energetic cosmic phenomena corresponding to supernovae and accreting supermassive black holes.
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Most important goals of XRISM are studying how matter and energy move through galaxies and gaining insights into the evolution of the structure of the universe.
XRISM’s “Resolve” X-ray microcalorimeter spectrometer was developed by a team led by NASA’s Goddard Space Flight Center. It should operate at 273.1 degrees Celsius, cooled by liquid helium. This requirement limits the lifetime of the mission, though it could be prolonged by mechanical cooling.
“We’ve been working to get an X-ray microcalorimeter camera in orbit for the reason that Nineteen Nineties,” Jonathan McDowell of the Harvard-Smithsonian Center for Astrophysics told . “It should give us unprecedented detail on the physical state of the million-degree hot gas in clusters of galaxies and black hole accretion disks, including the composition of the gas and, using the Doppler effect, how briskly it’s moving.
“Although XRISM won’t have the sharp vision (high spatial resolution) of Chandra or XMM, its high spectral resolution—like hyperspectral imagers on Earth observing satellites—shall be a game changer. It’s also a crucial test of the calorimeter prematurely of the subsequent generation of high-spatial-resolution X-ray telescopes.”
Moon sniper
SLIM meanwhile goals to make Japan the fifth country to soft land on the moon. The launch comes just two weeks after India became the fourth nation with the successful Chandrayaan-3 mission landing near the south pole, in addition to Russia’s Luna 25 lander which crashed into the moon following a failed orbital maneuver.
The 200 kg dry mass lander goals to display a small, lightweight landing system and pinpoint landing technology.
SLIM, also known as “Moon Sniper,” goals to set down inside 100 meters of its goal point using vision-based navigation. The lander carries observational data from the SELENE orbiter which shall be in comparison with features detected through the autonomous descent and landing. It will greatly reduce the landing ellipsis, or region inside which a probe is predicted to land based, which is normally on the order of kilometers.
The spacecraft will use a laser range finder, landing radar and navigation camera for the landing attempt, and carries two most important 500N engines and 12 smaller engines.
SLIM can even release two small probes, named Lunar Tour Vehicles (LEV), immediately before landing to record the landing site and display autonomous exploration.
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The lander has five, crushable aluminum lattice legs which can help absorb the impact of landing. The design will help it land on a slope inside Shioli crater at 25.2E, 13.3S on the moon’s near side.
SLIM carries a multi-band camera and a spectroscopic camera to look at surface composition, in addition to a passive laser retroreflector array. It should perform these tasks until the onset of lunar night, bringing an end to the mission.
The performance of SLIM landing technology could have relevance for a future mission. The joint Indian Space Research Organisation (ISRO) and JAXA Lunar Polar Exploration Mission (LUPEX) is predicted to launch later this decade.
Japanese company ispace failed with a moon landing attempt with its HAKUTO-R M1 lunar lander earlier this 12 months.
Wednesday’s launch was considered one of the ultimate missions for the H-2A, which is scheduled to get replaced by the brand new H3 rocket. That launcher’s first flight failed nonetheless earlier this 12 months, bringing a delay of months to the SLIM/XRISM launch.