Jonathan McDowell is the editor of Jonathan's Space Report, a freeinternet newsletter founded in 1989 covering technical details of space launches, and of the planet4589.org web site which includes the General Catalog of Artificial Space Objects. He has written papers on the boundary of outer space, the impacts of satellite megaconstellations on astronomy, compliancewith the UN Registration Convention, and other space policy topics. He uses open source analysis to report on what governments and companies are actually doing in space, as opposed to what's in their press releases, and as a result has been nicknamed the 'orbital police'.

McDowell is also an astrophysicist on the Chandra X-ray Center team at the Center for Astrophysics, Harvard and Smithsonian (CfA), supporting NASA's Chandra X-ray Observatory space telescope mission. He studies black holes and quasars, and leads the science software
algorithms team (`CXC Science Data Systems') for the Chandra X-ray Observatory. McDowell's astrophysics publications include studies of cosmology, black holes, galaxies, quasars, nearby galaxies, and asteroids.

Jonathan also co-directs the SAO Astronomy REU undergraduate summer program. and serves on the American Astronomical Society's COMPASSE light pollution committee as chair of the Space Debris subcommittee.

Jonathan has a B.A in Mathematics (1981) and a Ph.D in Astrophysics (1987) from Cambridge University. He did postdocs at Jodrell Bank, CfA and NASA-MSFC and has been at the Center for Astrophysics since 1992.

Jonathan is a dual US/UK citizen.

Minor planet (4589) McDowell is named after him.