NICER observation list: Target ID 252901


NuSTAR J092418-3142.2 (J0924) is the brightest 3-24 keV source found in the NuSTAR serendipitous survey. Although its classification is unclear, it is a strong candidate for being an ultracompact X-ray binary (typically, a neutron star accreting from a white dwarf) based on the lack of hydrogen lines in its optical spectrum and its low optical to X-ray luminosity ratio. UCXBs are of great interest since they are strong gravitational wave sources due to their short orbital periods and also because they provide an opportunity to understand the effects of elemental abundances on accretion. Here, we propose for NICER observations to do a sensitive search for pulsations from J0924, which will also provide a determination of the orbital period for this potentially very compact binary.
Obsid RA DEC l b Start End Exposure Number of
Number of
Status of
Date of
2529010101 141.075 -31.705 259.567 13.225 58767.6154 58767.9530 0.0 50 3 VALIDATED 58778.7 58781
2529010102 141.074 -31.704 259.566 13.224 58768.0032 58768.9856 0.0 50 3 VALIDATED 58778.7 58782
2529010103 141.075 -31.704 259.566 13.224 58769.0316 58769.4370 0.0 50 2 VALIDATED 58778.8 58783