NuSTAR Bringing the High Energy Universe into Focus


For Proposers

NuSTAR has been approved to continue operations through 2020 (subject to review by the 2019 NASA Astrophysics Senior Review of Operating Missions) including a General Observer (GO) Program.




The list of NuSTAR cycle-5 approved programs is available from:

Cycle-5 observations begin on July 1st, 2019 and the cycle ends on May 31st, 2020.

Upcoming opportunities to propose for NuSTAR observing time:


Gehrels-Swift observatory, cycle-16   September, 2019

XMM-Newton, cycle-19    October, 2019

NICER, cycle-2    December, 2019

The total amount of time allocated to GO observations is 11.3 Ms (~70% of the total observing time per year) including up to 8.5 Ms of observing time awarded to selected NuSTAR GO program investigations. It is anticipated that approximately 80 investigations will be selected for implementation in each NuSTAR GO cycle.
Of the remaining time (~ 3 Ms):
  • up to 1.5 Ms of NuSTAR observing time is expected to be awarded to joint NuSTAR/XMM-Newton proposals submitted to the XMM-Newton Cycle 19 Call for Proposals with proposals due in October, 2019. The list of accepted proposals for cycle-18 is available on the XMM-Newton OTAC results website.
  • up to 1.0 Ms of NuSTAR observing time for joint NuSTAR / Chandra observing projects submitted to the Chandra  Call for Proposals. Note that this includes up to 0.5 Ms reserved for V/LP programs. See CXC website for Cycle-20 peer review recommended programs. The proposal due date for Chandra cycle-22 is expected to be in March, 2019.
  • up to 100 ks of NuSTAR observing time for joint NuSTAR / INTEGRAL observing proposals submitted to the INTEGRAL Cycle 17 announcement of opportunity. The deadline for INTEGRAL AO-17 proposals is April 5th, 2019 at 14:00 CEST.
  • up to 300 ks of NuSTAR observing time for joint NuSTAR / Swift proposals is expected to be available in Swift cycle-16, with proposals due in September 2019.
    • Note that as a service to the community, "snapshot" (1 - 2 ks) observations are performed by NASA’s Swift mission for most NuSTAR observations (including GO programs).
  • up to 400 ks of NuSTAR observing time for joint NuSTAR / NICER proposals is expected to be available in NICER cycle-2, with proposals due in December, 2019. The list of accepted proposals for cycle-1 is available on the NICER GO website.
For the most complete list of planned and observed targets, as well as any ToOs that may be triggered before the beginning of Cycle 5 observations on June 1st 2019, please refer to the NuSTAR  Master Catalog at the HEASARC, which may be queried using either Browse or Xamin and the list of approved NuSTAR  ToO programs available on the NuSTAR  SOC website.
The remaining 35% of the observing time will be allocated through the NuSTAR  project as follows:
  • NuSTAR  legacy survey observations (~ 10% of the total observing time)
  • NuSTAR  PI discretionary time, including unanticipated ToO observations open to the scientific community (~ 15%)
  • Calibration observations, engineering tasks, and resolving operational issues (~ 10%).
Please see the NuSTAR  HEASARC Page for the latest information about NuSTAR. We've also provided useful links on the left including links to the NuSTAR observation constraint checker, the NuSTAR simulation toolkits, and details of the approved NuSTAR  legacy survey programs.