Blogs about stars

Messier 78 (ESA/Euclid/Euclid Consortium/NASA, image processing by J.-C. Cuillandre (CEA Paris-Saclay), G. Anselmi)

ESA and the Euclid Consortium have presented the first scientific results obtained thanks to the Euclid Space Telescope within the ERO (Early Release Observations) program. That’s a series of scientific articles partly written directly by the Consortium’s researchers and partly by different teams of researchers who worked within the ERO program. Some images illustrate the possibilities of this instrument but research into some of the major cosmological mysteries goes far beyond the aesthetics of photos.

Artistic representation of the exoplanet WASP-193 b

An article published in the journal “Nature Astronomy” reports the identification of the exoplanet WASP-193 b, a gas giant whose diameter is approximately 1.5 times Jupiter’s but with a mass that is only one-seventh of Jupiter’s. A team of researchers led by Khalid Barkaoui of the University of Li├Ęge, Belgium, used the WASP-South telescope of the Wide Angle Search for Planets (WASP) collaboration to locate WASP-193 b and then study its characteristics with other instruments. The combination of this exoplanet’s mass and density is really difficult to explain since no theory of planetary formation leads to a planet like this.

The quasar J0148+0600

An article published in “The Astrophysical Journal” reports the results of observations of primordial quasars that indicate that supermassive black holes form from “seeds” that are very massive and grow quickly. A team of researchers used observations conducted with the James Webb Space Telescope as part of the EIGER project to detect the faint light of the stars surrounding three of those quasars. This feat offers the possibility of obtaining much more information that allows to estimate the mass of galaxies and central supermassive black holes.

The estimates obtained for the three galaxies at the center of this study indicate that the primordial supermassive black holes were much more massive than today’s supermassive black holes compared to their host galaxies. According to the researchers’ reconstruction, primordial quasars powered by black holes engulfed materials at enormous speeds as they went from initial seeds to supermassive black holes.

A spectroscopic observation conducted with the James Webb Space Telescope's Near Infrared Spectrograph (NIRSpec) instrument of the galaxy Cosmos-11142 centered on the oxygen emission line doubly ionized

An article published in the journal “Nature” reports the observation of very strong winds coming from the supermassive black hole at the center of the galaxy Cosmos-11142 which inhibited star formation within it. A team of researchers led by Professor Sirio Belli of the University of Bologna, Italy, used the James Webb Space Telescope to detect the movement of cold neutral gas pushed at such a speed that it swept away the gas in the galaxy and thus prevented the formation of new stars. This is the first evidence of how a supermassive black hole can have that effect on a galaxy.

The position of the three stellar black holes discovered so far in the Milky Way, represented in projection, thanks to the Gaia mission.

An article published in the journal “Astronomy and Astrophysics Letters” reports the identification of a stellar black hole with a mass estimated to be approximately 33 times the Sun’s that was cataloged as Gaia BH3. A team of researchers used data collected by ESA’s Gaia space probe to find this black hole in the Milky Way’s halo, less than two thousand light-years from Earth. Its mass is remarkable for a stellar black hole and it has a companion, a very ancient star, as its age is estimated to be around 11 billion years.