NASA | GSFC | NICER | 2018 May 10
Scientists analyzing the first data from the Neutron star Interior Composition Explorer (NICER) mission have found two stars that revolve around each other every 38 minutes — about the time it takes to stream a TV drama. One of the stars in the system, called IGR J17062–6143 (J17062 for short), is a rapidly spinning, superdense star called a pulsar. The discovery bestows the stellar pair with the record for the shortest-known orbital period for a certain class of pulsar binary system.Click to play embedded YouTube video.
The data from NICER also show J17062’s stars are only about 186,000 miles (300,000 kilometers) apart, less than the distance between Earth and the Moon. Based on the pair’s breakneck orbital period and separation, scientists involved in a new study of the system think the second star is a hydrogen-poor white dwarf. ...
A previous 20-minute observation by the Rossi X-ray Timing Explorer (RXTE) in 2008 was only able to set a lower limit for J17062’s orbital period. NICER, which was installed aboard the International Space Station last June, has been able to observe the system for much longer periods of time. In August, the instrument focused on J17062 for more than seven hours over 5.3 days. Combining additional observations in October and November, the science team was able to confirm the record-setting orbital period for a binary system containing what astronomers call an accreting millisecond X-ray pulsar (AMXP). ...
NICER Discovers the Ultracompact Orbit of the Accreting Millisecond Pulsar IGR J17062–6143 - T. E. Strohmayer et al
- Astrophysical Journal Letters 858(2):L13 (10 May 2018) DOI: 10.3847/2041-8213/aabf44
arXiv.org > astro-ph > arXiv:1808.04392 > 13 Aug 2018