NASA’s Imaging X-ray, Polarimetry Explorer

Thursday Dec. 9th at 1:00 AM Est atop a Falcon 9 from LC-39A at Kennedy Space Center

Also called IXPE for short the two year NASA mission is to further understand our universe and explore exotic astronomical objects and permit mapping of the magnetic fields of black holes, neutron stars, pulsars, supernova remnants, magnetars, quasars and active galactic nuclei. High energy X-ray radiation from those objects surrounding environments can be polarized, or vibrating in a particular direction. Through studying these polarized X-rays may reveal the physics of these objects and can provide insights into the high temperature environments where they are created.

Picture by: Kyle Montogomery – NHS

This IXPE spacecraft was built by Ball Aerospace & Technologies, with the principle investigator is Martin C. Weisskopf of NASA’s Marshall Space Flight Center. He is also the chief scientist for X-ray astronomy at the Marshall Space Flight Center. First announced in 2017 it wasn’t until this week the mission was able to get off the ground. Years of building and planning was done between NASA and the Italian Space Agency. An estimated total cost of this mission, including the two years of it’s duration cost an estimated 188 million dollars, U.S.

Three identical imaging X-ray polarimetry systems, each mounted on a common optical bench, and co-aligned with the pointing a 4-meter focal length mirror module is the payload. Each of those 4-meter mirror assemblies focus the X-rays onto a polarization sensitive imaging detector that was developed in Italy. The crafts GPD (Gas Pixel Detectors) utilize the anisotropy of the emission direction of photoelectrons which are produced by the polarized photons to gauge with high sensitivity state of X-rays interacting in a gaseous medium. The system is capable to resolve point sources from surrounding nebular emission or from adjacent point sources. In short, the missions has a few main technical and science objectives. These include to improve polarization sensitivity by two orders of magnitude over the X-ray polarimeter aboard the Orbiting Solar Observatory 8. To provide simultaneous spectral, spatial, and temporal measurements. To determine the geometry and the emission mechanism of active galactic nuclei and micro quasars. Find the magnetic field configuration in magnetars and determine the magnitude of the field. Also to find the mechanism for X-ray production in pulsars and geometry and determine how particles are accelerated in pulsar wind nebula.

Picture by: Zac Shaul – NHS

IXPE is the first satellite dedicated to measuring the polarization of X-rays from different cosmic sources, as in black holes and neutron stars. The missions orbit will be hugging the equator to minimize the X-ray instruments exposure to radiation in the South Atlantic Anomaly. That’s the region where the inner Van Allen Radiation Belt comes closest to Earth’s surface. This mission is also the lightest payload, at 730lbs, ever launched from a SpaceX Falcon 9 rocket. It was thirty-three minutes into flight when the spacecraft separated from the second stage of the rocket. One minutes later the craft unfurled it’s solar arrays and entered its orbit around the equator at an altitude of 372 miles. Forty minutes after launching the spacecraft sent the first signal to operators at mission control.

This morning also marks the 97th successful landing of a SpaceX falcon 9 rocket first stage. B1061, the booster used on this mission has flown four times previous and has primarily been used on NASA missions, including Crew-1, Crew-2, and CRS-23. It’s odd mission out was SXM-8 where it launched Sirius Broadcasting’s newest satellite.