The primary reference for the NuSTAR mission is the article by Harrison, F.A. et al. (2013) ApJ, 770, 103 (2.9 MB PDF file) which contains information about the observatory and science instrument, the baseline science program, and the in-flight performance.

See also the NuSTAR Observatory Guide (7 MB pdf file) which provides information for potential proposers to the NuSTAR Guest Observer Program.

Artist's concept of NuSTAR in orbit

NuSTAR Mission Parameters

  • Mass: 350 kg
  • Power: 600 W
  • Orbit: LEO, 650 x 610 km
  • Orbital Inclination: 6 degrees
  • Orbital Lifetime: ~ 10 years

Key NuSTAR Performance Parameters

  • Energy Range: 3 - 78.4 keV
  • Angular resolution: 58" (HPD), 18" (FWHM)
  • FoV (50% resp.): 10' at 10 keV, 6' at 68 keV
  • Sensitivity (3σ, 1 Ms, ΔE/E = 0.5): 2 x 10-15 erg cm-2 s -1 in the 6-10 keV range
  • Sensitivity (3σ, 1 Ms, ΔE/E = 0.5): 1 x 10-14 erg cm-2 s -1 in the 10-30 keV range
  • Background in HPD: 1.1 x 10-3 ct s-1 (10-30 keV)
  • Background in HPD: 8.4 x 10-4 ct s-1 (30-60 keV)
  • Spectral Resolution (FWHM): 400 eV at 10 keV, 900 eV at 68 keV
  • Strong Source (>10σ) Positioning: 1.5" (1 σ)
  • Temporal resolution: 2 μs
  • ToO Response: < 24 hours
  • Slew Rate: 0.06 degrees s-1 ~ 3.6 degrees m-1
  • Settling Time: 200 s (typical)

NuSTAR's effective area compared
to Chandra and XMM-Newton

NuSTAR's effective area (in red) compared to the previous X-ray imaging missions Chandra and XMM-Newton


NuSTAR employs grazing incidence mirrors to focus the high-energy (3-79 keV) radiation. Two Wolter-I design telescopes point at the same portion of the sky, their images being added together on the ground.

Dimensions (Mirrors)

  • Length: 450 mm (1.5 ft.)
  • Radius: 191 mm (7.5 in.)
  • Focal Length: 10.14 m (33 ft.)

More details on the optics.

Deployable Mast

NuSTAR is a Small Explorer mission and had to fit inside the Pegasus launch vehicle: at launch, NuSTAR was no more than two meters long and one meter in diameter. Therefore, to attain the required 10m focal length needed for its telescopes, NuSTAR used a unique deployable mast, or boom, that extended the optics after the payload was in orbit.

More details on the deployable mast.

CdZnTe Detectors

NuSTAR has two detector units, each at the focus of one of the two co-aligned NuSTAR optics units. The focal planes are each comprised of four 32 x 32 pixel Cadmium-Zinc-Tellurium (CdZnTe, or CZT) detectors. These are "state-of-the-art" room-temperature semiconductors which are very efficient at turning high energy photons into electrons.

More details on the detectors.