Nuclear Spectroscopic Telescope Array

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NuSTAR
NuSTAR
Type: X-ray telescope
Country: United StatesUnited States United States
Operator: National Aeronautics and Space AdministrationNASA NASA
COSPAR-ID : 2012-031A
Mission dates
Dimensions: 360 kg
Begin: June 13, 2012, 16:00 UTC
Starting place: Kwajalein
Launcher: Pegasus-XL
Status: in operation
Orbit data
Rotation time : 96.8 min
Orbit inclination : 6 °
Apogee height :  619 km
Perigee height :  604 km

Nuclear Spectroscopic Telescope Array ( NuSTAR ) is an orbital X-ray telescope for observing X-ray sources such as black holes . NuSTAR is a satellite in the Explorer program of NASA . After reaching the orbit, NuSTAR was given the additional designation Explorer 93 .

mission

NuSTAR is an X-ray astronomy mission which for the first time allows imaging with a spatial resolution of less than one arc minute in the high-energy X-ray range. Earlier missions with Wolter telescopes such as Chandra or XMM-Newton worked up to energies of 10  keV . NuSTAR will expand the examination range up to 80 keV. With these energies, only poor spatial resolution was previously possible using collimators .

The questions to be answered by NuSTAR include the distribution of black holes, the formation of heavy elements and the mechanisms of energy generation in active galaxies .

NuSTAR was selected as a SMEX ( Small Explorer ) mission in 2005 , but development was stopped in February 2006 for cost reasons. In September 2007, NASA put the NuSTAR mission back into the budget.

NuSTAR was originally supposed to be launched in February 2012 with a Pegasus XL rocket, but the launch was postponed several times. It finally took place on June 13, 2012. The Lockheed L-1011 carrier aircraft took off from the Kwajalein Atoll and disengaged the Pegasus XL about 193 km south of the take-off location. Then the rocket flew into the planned earth orbit. The altitude of NuSTAR's orbit is about 600 km, the inclination 6 °. On June 21, 2012, the 56-segment mast, around 10 meters long, was extended within 26 minutes. The two Wolter telescopes at the end of the mast can now focus the X-rays on the detectors.

The lead scientist is Fiona Harrison .

construction

Original NuSTAR planning

The 360 ​​kg satellite is based on the commercial LEOSTAR-2 satellite structure from Orbital Sciences Corporation , which was already used in a similar form in the GALEX satellite . The satellite body has the shape of a hexagonal prism and offers three-axis stabilization . An adjustable solar cell boom provides the power supply. The planned duration of the mission is two years.

The NuSTAR instrument consists of two X - ray telescopes aligned in the same orientation (three were originally planned). The X-rays are focused using Wolter telescopes that are mounted on an extendable, ten-meter-long boom. The boom allows a long focal length of the telescope and thus a very flat angle of incidence of the X-ray radiation on the mirrors. This means that X-rays above 10 keV can also be reflected. The telescopes focus the radiation on three cadmium zinc telluride (CdZnTe) detectors located on the satellite body. The detectors do not require cryogenic cooling and have a high spectral resolution.

Originally (before the program interruption in 2006) NuStar was to be built on the basis of the Spectrum Astro SA-200S satellite bus.

Results

In 2017, this telescope, like the XMM Newtonian, was involved in the detection of ultrafast winds from a superheavy black hole. These reached a quarter of the speed of light and showed an interaction with the X-rays that caused the material falling into the black hole.

Web links

Commons : Nuclear Spectroscopic Telescope Array  - collection of images, videos and audio files

Individual evidence

  1. ↑ Railway data according to NUSTAR. N2YO, July 10, 2018, accessed July 11, 2018 .
  2. ^ Statement by Mary L. Cleave - House Science Committee Hearing on NASA FY 2007 Science Budget
  3. ↑ Caltech Media Relations: Small Explorer Mission to Detect Black Holes Scheduled for 2011 Launch ( Memento of February 29, 2008 in the Internet Archive ) (September 21, 2007)
  4. ↑ Air-launched Pegasus boosts NASA telescope to space. Spaceflight now, June 13, 2012, accessed June 14, 2012 .
  5. ↑ NuSTAR Mission Status Report: Observatory Unfurls its Unique Mast. Jet Propulsion Laboratory, June 21, 2012, accessed June 22, 2012 .
  6. ^ Gunter Krebs: Explorer: NuSTAR (SMEX 11). In: Gunter's Space Page. March 8, 2012, accessed April 4, 2012 .
  7. ↑ Michael L. Parker et al .: The response of relativistic outflowing gas to the inner accretion disk of a black hole, in: Nature 543, 2017, pp. 83-86