HALOMASTER ivo://nasa.heasarc/halomaster NASA/GSFC HEASARC HEASARC 2026-10-09 NASA/GSFC HEASARC help desk heasarc-vo at athena.gsfc.nasa.gov Observation This table records high-level information for the observations obtained with HaloSat and provides access to the HaloSat data archive. HaloSat is the first astrophysics-focused CubeSat funded by NASA's Astrophysics Division (PI P. Kaaret, University of Iowa). HaloSat is designed to map soft X-ray oxygen line emissions across the sky in order to constrain the mass and spatial distribution of hot gas in the Milky Way. HaloSat was launched from the NASA Wallops Flight Facility and delivered to the International Space Station on May 21, 2018. HaloSat was deployed into orbit on July 13, 2018. The spacecraft and science instrument commissioning phase ended on October 16, 2018, and science operations started after that. Initially approved to operate for 12 months, HaloSat successfully collected science data from October 15, 2018, until September 29, 2020, effectively doubling the mission lifetime. HaloSat reentered Earth's atmosphere on January 4, 2021. To trace the Galactic halo, HaloSat is equipped with a non-focusing instrument, comprised of three independent silicon drift detectors (SDD14, SDD38, SDD54) operating in the energy range of 0.4 - 7.0 keV with a field of view of 10 deg in diameter and an energy resolution of 84.8 +/- 2.7 eV at 677 eV and 137.4 +/- 0.9 eV at 5895 eV. The observing strategy was to divide the sky into 333 positions (HaloSat fields) and acquire a minimum of 8000 detector-seconds for each position throughout the initial 12 months of operations. After launch, additional positions were added to the initial 333 positions. HaloSat observations of the chosen fields are divided in intervals of time such that the data files do not exceed 2GB. Each observation is labeled with a sequence number. This database table contains one record for each sequence number and includes parameters related to the observation. The contents of this database table are generated at the HEASARC using information from the data files. The table was last updated in April 2023. This is a service provided by NASA HEASARC . 2019ApJ...884..162K https://heasarc.gsfc.nasa.gov/W3Browse/all/halomaster.html Archive Research served-by HEASARC TAP https://heasarc.gsfc.nasa.gov/xamin/vo/cone?showoffsets&table=halomaster& GET text/xml 180 99999 true 248.894348144531 -88.3999862670898 0.25 https://heasarc.gsfc.nasa.gov/xamin/vo/tap https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/getvotable.pl?name=halomaster GET text/xml https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/w3query.pl?tablehead=name=heasarc_halomaster&Action=More+Options&Action=Parameter+Search&ConeAdd=1 https://heasarc.gsfc.nasa.gov/xamin/vo/ssa?table=halomaster& GET text/xml+votable query pointed archival FK4 360.0 500 10000 180 10000000 POS=248.894348144531,-88.3999862670898&SIZE=0.25&REQUEST=queryData HALOSAT 0.25 X-ray public halomaster HaloSat Master Catalog obsid Unique Observation/Sequence Numerical Identifier meta.id;obs char nullable name Target Designation meta.id;meta.main char nullable ra Right Ascension of the Pointing Position degree pos.eq.ra;meta.main double nullable dec Declination of the Pointing Position degree pos.eq.dec;meta.main double nullable "time" Start Time of the Observation mjd time.start;obs double nullable end_time Stop Time of the Observation mjd time.end;obs double nullable exposure Effective Total Observation Exposure s time.duration;obs.exposure double nullable events_s54 Number of Cleaned Events in S54 Detector meta.number int nullable processing_date Date of Processing mjd time.processing double nullable bii Galactic Latitude of the Pointing Position degree pos.galactic.lat double nullable software_version Software Version Used in the Pipeline meta.version;meta.software char nullable obs_type Object/Observation Type meta.code;obs char nullable lii Galactic Longitude of the Pointing Position degree pos.galactic.lon double nullable events_s38 Number of Cleaned Events in S38 Detector meta.number int nullable processing_version Version of Processing Script meta.version;meta.dataset char nullable events_s14 Number of Cleaned Events in S14 Detector meta.number int nullable caldb_version Version of the Calibration Database (CALDB) Used for Processing meta.version;instr.calib char nullable "__x_ra_dec" System unit vector column double nullable "__y_ra_dec" System unit vector column double nullable "__z_ra_dec" System unit vector column double nullable "__row" System index column char nullable