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Department of Space, Indian Space Research Organisation


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2.1 AO cycle

AstroSat is operated in a pre-planned manner i.e proposers are not present at Mission Operations Complex during the execution of their observations. Thus, all observations must be specified in full details in advance.

  • The percentage of observing time for executing AO proposals during April to September 2017 is ~35% and is termed as second AO cycle.
  • This 35% time is exclusive for Indian proposers as Principal Investigators (PIs) to utilise AstroSat observatory time. They could be interested  researchers, scientists and astronomy community at large, involved in scientific research in the field of astronomy and are equipped to submit proposals as Principal Investigators (PIs) for specific target observations with necessary scientific and technical justification and can analyse the data, if the target is observed based on approvals.
  • In order to expand the AstroSat user community, it  is  recommended  that those  who  are  submitting proposals  as PIs in Guaranteed Time (GT)  cycle, encourage  other astronomers  to be  PI  in AO  proposals. If a proposer from a university, college or any institution submitting a proposal under AO cycle wishes to have a   Co-I from any payload teams to get help in data analysis or needs support on science related issues, he/she may do so in consultation with the payload team leads as provided in the handbook.
  • All the selected AO proposals will be inserted into the observing schedule. However, few observations approved in this AO cycle may be scheduled outside of the above period, in case there is operations requirement, which will be provided by AstroSat Mission.
  • Proposers are requested not to duplicate any of the planned observations and should carefully justify duplications if any, with performed observations. Proposers have to check the list of objects and instrument parameters for observations already/ being carried out using AstroSat. A Red book containing these targets will be made available in the ISSDC website. Proposers wishing to observe any of these targets should justify why it is important to do so and what additional information will come from the proposed observations. See also section 4.
  • Checks for duplications will be performed by ATAC while processing the proposals during the scientific review.