Awareness in the fields of IT, Space - Station Explorer for X-ray Timing and Navigation Technology January 14, 2018 NASA has invented a new type of autonomous space navigation that could see human-made spacecraft heading into the far reaches of the Solar System, and even farther – by using pulsars as guide stars. It’s called Station Explorer for X-ray Timing and Navigation Technology, or SEXTANT (named after an 18th century nautical navigation instrument). About Station Explorer for X-ray Timing and Navigation Technology: What is it? SEXTANT works like a GPS receiver getting signals from at least three GPS satellites, all of which are equipped with atomic clocks. The receiver measures the time delay from each satellite and converts this into spatial coordinates. How it works? The technology uses X-ray technology to see millisecond pulsars, using them much like a GPS uses satellites. The electromagnetic radiation beaming from pulsars is most visible in the X-ray spectrum, which is why NASA’s engineers chose to employ X-ray detection in SEXTANT. To do so, they used a washing machine-sized observatory attached to the International Space Station. Called Neutron-star Interior Composition Explorer, or NICER, it contains 52 X-ray telescopes and silicon-drift detectors for studying neutron stars, including pulsars. Applications: SEXTANT could be used to calculate the location of planetary satellites far from the range of Earth’s GPS satellites, and assist on human spaceflight missions, such as the space agency’s planned Mars mission. What are pulsars? Pulsars are highly magnetised, rapidly rotating neutron stars – the result of a massive star’s core collapsing and subsequently exploding. As they spin, they emit electromagnetic radiation. If an observer is in the right position, they can appear as sweeping beams, like a cosmic lighthouse. They’re also extraordinarily regular – in the case of some millisecond pulsars, which can spin hundreds of times a second, their regularity can rival that of atomic clocks.