NASA | MSFC | SAO | Chandra X-Ray Observatory | 2019 Jan 29
A new study using data from NASA's Chandra X-ray Observatory and ESA's XMM-Newton suggests that dark energy may have varied over cosmic time, as reported in our latest press release. This artist's illustration helps explain how astronomers tracked the effects of dark energy to about one billion years after the Big Bang by determining the distances to quasars, rapidly growing black holes that shine extremely brightly.
First discovered about 20 years ago by measuring the distances to exploded stars called supernovas, dark energy is a proposed type of force, or energy, that permeates all space and causes the expansion of the Universe to accelerate. Using this method, scientists tracked the effects of dark energy out to about 9 billion years ago.
The latest result stems from the development of a new method to determine distances to about 1,598 quasars, which allows the researchers to measure dark energy's effects from the early Universe through to the present day. Two of the most distant quasars studied are shown in Chandra images in the insets. ...
Active Galaxies Point to New Physics of Cosmic Expansion
ESA | Space Science | Science & Technology | XMM-Newton | 2019 Jan 28
Cosmological Constraints from the Hubble Diagram of Quasars at High Redshifts ~ Guido Risaliti, Elisabeta Lusso
- Nature Astronomy (online 28 Jan 2019) DOI: 10.1038/s41550-018-0657-z
arXiv.org > astro-ph > arXiv:1811.02590 > 06 Nov 2018