Daniel Stern is a research scientist at NASA's Jet Propulsion Laboratory (JPL). He is a project scientist for the Nuclear Spectroscopic Telescope Array (NuSTAR) mission and the Deputy Principal Investigator of the NASA-Funded Euclid Science Team. His main research interests are identifying and studying galaxies and galaxy clusters at high redshift, as well as understanding the cosmic history of black hole formation and activity.
Quadruply Imaged Quasars - Daniel Stern of NASA’s Jet Propulsion Laboratory discovers the so-called quadruply imaged quasars, or quads, that can help solve many cosmological puzzles. Quads occur when the gravity of a massive galaxy that happens to sit in front of a quasar splits its single image into four.