SEXTANT - Station Explorer for X-ray Timing and Navigation Technology

Mitchell, Jason W.; Hasouneh, Munther Abdel Hamid; Winternitz, Luke M. B.; Valdez, Jennifer E.; Price, Samuel R.; Semper, Sean R.; Yu, Wayne H.; Arzoumanian, Zaven; Ray, Paul S.; Wood, Kent S.; Litchford, Ronald J.; Gendreau, Keith C.

NASA NTRS · 20150001327

SEXTANT - Station Explorer for X-ray Timing and Navigation Technology

Mitchell, Jason W.·Hasouneh, Munther Abdel Hamid·Winternitz, Luke M. B.·Valdez, Jennifer E.·Price, Samuel R.·Semper, Sean R.·Yu, Wayne H.·Arzoumanian, Zaven·Ray, Paul S.·Wood, Kent S.·Litchford, Ronald J.·Gendreau, Keith C.

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Abstract

The Station Explorer for X-ray Timing and Navigation Technology (SEXTANT) is a technology demonstration enhancement to the Neutron-star Interior Composition Explorer (NICER) mission, which is scheduled to launch in late 2016 and will be hosted as an externally attached payload on the International Space Station (ISS) via the ExPRESS Logistics Carrier (ELC). During NICER's 18-month baseline science mission to understand ultra-dense matter though observations of neutron stars in the soft X-ray band, SEXTANT will, for the first-time, demonstrate real-time, on-board X-ray pulsar navigation, which is a significant milestone in the quest to establish a GPS-like navigation capability that will be available throughout our Solar System and beyond. Along with NICER, SEXTANT has proceeded through Phase B, Mission Definition, and received numerous refinements in concept of operation, algorithms, flight software, ground system, and ground test capability. NICER/SEXTANT's Phase B work culminated in NASA's confirmation of NICER to Phase C, Design and Development, in March 2014. Recently, NICER/SEXTANT successfully passed its Critical Design Review and SEXTANT received continuation approval in September 2014. In this paper, we describe the X-ray pulsar navigation concept and provide a brief history of previous work, and then summarize the SEXTANT technology demonstration objective, hardware and software components, and development to date.

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Mitchell, Jason W., Hasouneh, Munther Abdel Hamid, Winternitz, Luke M. B., Valdez, Jennifer E., Price, Samuel R., Semper, Sean R., Yu, Wayne H., Arzoumanian, Zaven, Ray, Paul S., Wood, Kent S., Litchford, Ronald J., Gendreau, Keith C.. 2015-01-05. SEXTANT - Station Explorer for X-ray Timing and Navigation Technology. https://ntrs.nasa.gov/citations/20150001327

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