The researchers also identified large masses of previously undetected material surrounding galaxies, and described the large-scale flows of this gas. The results were published in three papers in the Nov. 18 edition of the journal Science.
The leaders of the three studies are Lehner of Notre Dame, Todd Tripp of the University of Massachusetts at Amherst, and Jason Tumlinson of the Space Telescope Science Institute in Baltimore. The researchers used the Cosmic Origins Spectrograph on the Hubble Space Telescope to detect the mass in the halos of the Milky Way and more than 40 other galaxies. The process uses absorption lines in the high-resolution spectra of background quasars or stars to detect the gases in the clouds, which are invisible to other kinds of imaging. Data from the Large Binocular Telescope in Arizona, Keck in Hawaii and the Magellan Telescope in Chile were also key to the studies by measuring the properties of the galaxies.
"We show that not only there is enough mass in the gas flows in halos of galaxies to sustain star formation over billions of years, but also the mass in the hot halos of star-forming galaxies is phenomenal–as large as the mass of gas in the disk of a galaxy," says Lehner.Clouds of ionized hydrogen within 20,000 light years of the Milky Way disk contain enough material to make 100 million suns. About one solar mass of that gas falls into the Milky Way every year, comparable to the rate at which our galaxy makes stars. The cycle could continue for several billion years.
In more distant galaxies, the team found element-rich halos around star-forming galaxies, including surprising levels of heavy elements up to 450,000 light years beyond the visible portion of the galactic disks. The Cosmic Origins Spectrograph measured 10 million solar masses of oxygen in a galaxy's halo, which corresponds to about 1 billion solar masses of gas.
The light of a distant quasar shines through the invisible gaseous halo of a foreground galaxy. Elements in the halo absorb certain frequencies of light. They become detectable, and can be used to measure the halo's mass.
Some of the galaxies that form stars at a very rapid rate, perhaps a hundred solar masses per year, can drive million-degree Fahrenheit gas very far out into intergalactic space at speeds of up to 2 million miles per hour. This is fast enough for the gas to escape forever and never refuel the parent galaxy. "We have observed hot gas in the process of moving out of a galaxy and into intergalactic space," Tripp says.
"Our results confirm a theoretical suspicion that galaxies expel and can recycle their gas, but they also present a fresh challenge to theoretical models to understand these gas flows and integrate them with the overall picture of galaxy formation," Tumlinson says.
Nicolas Lehner | EurekAlert!
Black phosphorus-based van der Waals heterostructures for mid-infrared light-emission applications
13.07.2020 | Light Publishing Center, Changchun Institute of Optics, Fine Mechanics And Physics, Chinese Academy
Robust high-performance data storage through magnetic anisotropy
13.07.2020 | Helmholtz-Zentrum Berlin für Materialien und Energie
Biochemists at Martin Luther University Halle-Wittenberg (MLU) have used a standard electron cryo-microscope to achieve surprisingly good images that are on par with those taken by far more sophisticated equipment. They have succeeded in determining the structure of ferritin almost at the atomic level. Their results were published in the journal "PLOS ONE".
Electron cryo-microscopy has become increasingly important in recent years, especially in shedding light on protein structures. The developers of the new...
New insight into the spin behavior in an exotic state of matter puts us closer to next-generation spintronic devices
Aside from the deep understanding of the natural world that quantum physics theory offers, scientists worldwide are working tirelessly to bring forth a...
Kiel physics team observed extremely fast electronic changes in real time in a special material class
In physics, they are currently the subject of intensive research; in electronics, they could enable completely new functions. So-called topological materials...
Solar cells based on perovskite compounds could soon make electricity generation from sunlight even more efficient and cheaper. The laboratory efficiency of these perovskite solar cells already exceeds that of the well-known silicon solar cells. An international team led by Stefan Weber from the Max Planck Institute for Polymer Research (MPI-P) in Mainz has found microscopic structures in perovskite crystals that can guide the charge transport in the solar cell. Clever alignment of these "electron highways" could make perovskite solar cells even more powerful.
Solar cells convert sunlight into electricity. During this process, the electrons of the material inside the cell absorb the energy of the light....
Empa researchers have succeeded in applying aerogels to microelectronics: Aerogels based on cellulose nanofibers can effectively shield electromagnetic radiation over a wide frequency range – and they are unrivalled in terms of weight.
Electric motors and electronic devices generate electromagnetic fields that sometimes have to be shielded in order not to affect neighboring electronic...
07.07.2020 | Event News
02.07.2020 | Event News
19.05.2020 | Event News
14.07.2020 | Information Technology
14.07.2020 | Life Sciences
14.07.2020 | Life Sciences