A dense cluster of hot stars with whisps of gas around it.
NASA, ESA, R. O'Connell (University of Virginia), F. Paresce (National Institute for Astrophysics, Bologna, Italy), E. Young (Universities Space Research Association/Ames Research Center), the WFC3 Science Oversight Committee, and the Hubble Heritage Team (STScI/AURA)


The Hubble Space Telescope is the astronomical community's best instrument for ultraviolet observations of our Universe. OKC researchers use this telescope to study supernovae and their surroundings, clusters of forming stars, and gas inside and between galaxies. In the most recent call for proposals, Cycle 26, two OKC:ers had their "medium" proposals accepted.

Stockholm University researcher Angela Adamo received the most orbits (60) of any researcher proposing from outside the US. Angela says, "we will take advantage of the unmatched ultraviolet capability of the Hubble Space Telescope to investigate a sample of very young star clusters. These systems contains between 100 thousands and a million stars, thus they are among the densest stellar structures forming in galaxies. When very young, star clusters contain the most massive stars forming in galaxies and this property makes them extremely bright in the ultraviolet. We will determine the number of very massive stars that they contain and the effect of their feedback on their host galaxies."

Stockholm University associate professor Matthew Hayes says he will use his 55 orbits for a new project that is "concerned with the so-called 'circumgalactic' gas -- that which surrounds galaxies and is detected out to radial distances about 10 times beyond the scales where we detect light from stars.  We believe it to be particularly important because this constitutes a very massive reservoir of material that one day may find itself inside the galaxy, where it may become the fuel for future star formation.  One of the best ways to image this gas in an individual galaxy is to look for extended emission of Lyman-alpha radiation, which acts as a flashlight to illuminate circumgalactic hydrogen."