X-ray astronomy is an observational branch of astronomy which deals with the study of X-ray observation and detection from astronomical objects. X-radiation is absorbed by the Earth's atmosphere, so instruments to detect X-rays must be taken to high altitude by balloons, sounding rockets, and satellites. X-ray astronomy uses a type of space telescope that can see x-ray radiation which standard optical telescopes, such as the Mauna Kea Observatories, cannot.
X-rays start at ~0.008 nm and extend across the electromagnetic spectrum to ~8 nm, over which the Earth's atmosphere is opaque.
NRL scientists J. D. Purcell, C. Y. Johnson, and Dr. F. S. Johnson are among those recovering instruments from a V-2 used for upper atmospheric research above the New Mexico desert. This is V-2 number 54, launched January 18, 1951, (photo by Dr. Richard Tousey, NRL).
Navy Deacon rockoon photographed just after a shipboard launch in July 1956.
One of the mirrors of XRISM made of 203 foils
A sounding rocket or rocketsonde, sometimes called a research rocket or a suborbital rocket, is an instrument-carrying rocket designed to take measurements and perform scientific experiments during its sub-orbital flight. The rockets are used to launch instruments from 48 to 145 km above the surface of the Earth, the altitude generally between weather balloons and satellites; the maximum altitude for balloons is about 40 km and the minimum for satellites is approximately 121 km. Certain sounding rockets have an apogee between 1,000 and 1,500 km, such as the Black Brant X and XII, which is the maximum apogee of their class. Sounding rockets often use military surplus rocket motors. NASA routinely flies the Terrier Mk 70 boosted Improved Orion, lifting 270–450-kg (600–1,000-pound) payloads into the exoatmospheric region between 97 and 201 km.
A Black Brant XII being launched from Wallops Flight Facility
Sample payloads for sounding rockets
A Loki-Dart (foreground) on display at the White Sands Missile Range rocket garden