WASHINGTON — NASA will develop a gamma-ray telescope intended to study the formation of chemical elements in the galaxy as its next small astrophysics mission.

18 that it will proceed with development of the Compton Spectrometer and Imager (COSI) spacecraft as its next small Explorer, or SMEX, astrophysics mission.

“COSI will answer questions about the origin of the chemical elements in our own Milky Way galaxy, the very ingredients critical to the formation of Earth itself,” Thomas Zurbuchen, NASA associate administrator for science, said in a statement about the selection of the mission.

NASA’s selection of COSI comes as the previous astrophysics SMEX mission nears launch.