Category Astronomy/Space

For the first time, astronomers have linked a mysterious Fast Radio Burst with Gravitational Waves

For the first time, astronomers have linked a mysterious fast radio burst with gravitational waves
Credit: ASKAP, CSIRO

We have just published evidence in Nature Astronomy for what might be producing mysterious bursts of radio waves coming from distant galaxies, known as fast radio bursts or FRBs.

Two colliding neutron stars—each the super-dense core of an exploded star—produced a burst of gravitational waves when they merged into a “supramassive” neutron star. We found that two and a half hours later they produced an FRB when the neutron star collapsed into a black hole.

Or so we think. The key piece of evidence that would confirm or refute our theory—an optical or gamma-ray flash coming from the direction of the fast radio burst—vanished almost four years ago. In a few months, we might get another chance to find out if we are correct.

Brief and powerful
FRBs are in...

Read More

AI finds the First Stars were Not Alone

A schematic illustration of the first star’s supernovae and observed spectra of extremely metal-poor stars. Ejecta from the supernovae enrich pristine hydrogen and helium gas with heavy elements in the universe (cyan, green, and purple objects surrounded by clouds of ejected material). If the first stars are born as a multiple stellar system rather than as an isolated single stars, elements ejected by the supernovae are mixed together and incorporated into the next generation of stars. The characteristic chemical abundances in such a mechanism are preserved in the atmosphere of the long-lived low-mass stars observed in our Milky Way Galaxy...
Read More

Artificial Intelligence discovers Secret Equation for ‘Weighing’ Galaxy Clusters

Astrophysicists at the Institute for Advanced Study, the Flatiron Institute and their colleagues have leveraged artificial intelligence to uncover a better way to estimate the mass of colossal clusters of galaxies. The AI discovered that by just adding a simple term to an existing equation, scientists can produce far better mass estimates than they previously had.

The improved estimates will enable scientists to calculate the fundamental properties of the universe more accurately, the astrophysicists reported March 17, 2023, in the Proceedings of the National Academy of Sciences.

“It’s such a simple thing; that’s the beauty of this,” says study co-author Francisco Villaescusa-Navarro, a research scientist at the Flatiron Institute’s Center for Computational Astrophysics (CCA) in...

Read More

Small Stars may Host Bigger Planets than previously thought

Artist’s impression of sunrise on planet NGTS-1b, a gas giant previously discovered orbiting a low-mass star. Credit: University of Warwick/Mark Garlick

Stars with less than half the mass of our sun are able to host giant Jupiter-style planets, in conflict with the most widely accepted theory of how such planets form, according to a new study led by UCL (University College London) and University of Warwick researchers.

Gas giants, like other planets, form from disks of material surrounding young stars. According to core accretion theory, they first form a core of rock, ice and other heavy solids, attracting an outer layer of gas once this core is sufficiently massive (about 15 to 20 times that of Earth).

However, low-mass stars have low-mass disks that, models predict, would not provide enough material to form a gas giant in this way, or at least not quickly enough before the disk breaks up.

In the study, accepted for publica...

Read More