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The one to watch here is the X ray telescope. JAXA previously lost Hitomi, which was a very promising mission, so hopefully this time they get to use the actual

The one to watch here is the X ray telescope. JAXA previously lost Hitomi, which was a very promising mission, so hopefully this time they get to use the actual payload.

Aachen 3y ago
Hadn't heard of x-ray space telescopes before so this sounded like a cool new thing to avoid atmospheric interference and do better measurements, perhaps even in the moon's shadow to avoid earth-originating noise, but then I looked up whether there have been others and there's a whole host of them: https://en.m.wikipedia.org/wiki/List_of_X-ray_space_telescopes https://en.m.wikipedia.org/wiki/List_of_X-ray_space_telescop... What would we do with yet another one? Clicking through to the article about this telescope: > As the only international X-ray observatory project of its period, XRISM will function as a next generation space telescope in the X-ray astronomy field, similar to how the James Webb Space Telescope, Fermi Space Telescope, and the Atacama Large Millimeter Array (ALMA) Observatory are placed in their respective fields. The mission is a stopgap for avoiding a potential observation period gap between X-ray telescopes of the present (Chandra, XMM-Newton) and those of the future (Advanced Telescope for High Energy Astrophysics (ATHENA)). Without XRISM, a blank period in X-ray astronomy may arise in the early 2020s due to the loss of Hitomi. –https://en.m.wikipedia.org/wiki/X-Ray_Imaging_and_Spectroscopy_Mission https://en.m.wikipedia.org/wiki/X-Ray_Imaging_and_Spectrosco... You also made me curious why Hitomi got "lost" (launch failure? Micrometeorite? Hard-/software failure?) From its article at https://en.m.wikipedia.org/wiki/Hitomi_(satellite) https://en.m.wikipedia.org/wiki/Hitomi_(satellite) > [Problems] began with its inertial reference unit (IRU) reporting a rotation of 21.7° per hour at 19:10 UTC on 25 March 2016, though the vehicle was actually stable. The attitude control system attempted to [correct that nonexistent spin, spun it faster and faster, and that broke it up] What caused this glitch or what was known on the ground at the time (did they know it wasn't spinning but couldn't tell it to stop?) is not mentioned Edit: oh but it did science in the 36 days that it operated! > Measurements by Hitomi have allowed scientists to track the motion of X-ray-emitting gas at the heart of the Perseus cluster of galaxies for the first time. Using the Soft X-ray Spectrometer, astronomers have mapped the motion of X-ray-emitting gas in a cluster of galaxies and shown it moves at cosmically modest speeds. [...] [So now we know] turbulence is responsible for only about 4 percent of the total gas pressure.

The one to watch here is the X ray telescope. JAXA previously lost Hitomi, which was a very promising mission, so hopefully this time they get to use the actual payload.

Aachen 3y ago

Hadn't heard of x-ray space telescopes before so this sounded like a cool new thing to avoid atmospheric interference and do better measurements, perhaps even in the moon's shadow to avoid earth-originating noise, but then I looked up whether there have been others and there's a whole host of them: https://en.m.wikipedia.org/wiki/List_of_X-ray_space_telescopes https://en.m.wikipedia.org/wiki/List_of_X-ray_space_telescop... What would we do with yet another one? Clicking through to the article about this telescope: > As the only international X-ray observatory project of its period, XRISM will function as a next generation space telescope in the X-ray astronomy field, similar to how the James Webb Space Telescope, Fermi Space Telescope, and the Atacama Large Millimeter Array (ALMA) Observatory are placed in their respective fields. The mission is a stopgap for avoiding a potential observation period gap between X-ray telescopes of the present (Chandra, XMM-Newton) and those of the future (Advanced Telescope for High Energy Astrophysics (ATHENA)). Without XRISM, a blank period in X-ray astronomy may arise in the early 2020s due to the loss of Hitomi. –https://en.m.wikipedia.org/wiki/X-Ray_Imaging_and_Spectroscopy_Mission https://en.m.wikipedia.org/wiki/X-Ray_Imaging_and_Spectrosco... You also made me curious why Hitomi got "lost" (launch failure? Micrometeorite? Hard-/software failure?) From its article at https://en.m.wikipedia.org/wiki/Hitomi_(satellite) https://en.m.wikipedia.org/wiki/Hitomi_(satellite) > [Problems] began with its inertial reference unit (IRU) reporting a rotation of 21.7° per hour at 19:10 UTC on 25 March 2016, though the vehicle was actually stable. The attitude control system attempted to [correct that nonexistent spin, spun it faster and faster, and that broke it up] What caused this glitch or what was known on the ground at the time (did they know it wasn't spinning but couldn't tell it to stop?) is not mentioned Edit: oh but it did science in the 36 days that it operated! > Measurements by Hitomi have allowed scientists to track the motion of X-ray-emitting gas at the heart of the Perseus cluster of galaxies for the first time. Using the Soft X-ray Spectrometer, astronomers have mapped the motion of X-ray-emitting gas in a cluster of galaxies and shown it moves at cosmically modest speeds. [...] [So now we know] turbulence is responsible for only about 4 percent of the total gas pressure.