Paul M. Sutter, Author at Universe Today

March 8, 2021March 8, 2021 by Paul M. Sutter

Dust in the Chixalub Crater Makes the Compelling Case That an Asteroid Wiped out the Dinosaurs 65 Million Years ago

Impactors strike during the reign of the dinosaurs (image credit: MasPix/devianart)

For decades scientists have believed that an asteroid impact event ended the era of the dinosaurs 66 million years ago. Now, analysis from the crater site itself seals the deal: the same elements that were deposited around the world from the impact have been found inside the crater itself.

February 4, 2021February 1, 2021 by Paul M. Sutter

Astronomers are now Finding Planetary Disks Around the Smallest, Least Massive Stars

Astronomers have been watching planetary systems form around sun-like stars for decades. And now, new observations with the ALMA telescope reveal the same process playing out around the smallest, but most common, stars in galaxy.

February 4, 2021February 6, 2021 by Paul M. Sutter

Narrowing Down the Mass of Dark Matter

A section of the virtual universe, a billion light years across, showing how dark matter is distributed in space, with dark matter halos the yellow clumps, interconnected by dark filaments. Cosmic void, shown as the white areas, are the lowest density regions in the Universe. Credit: Joachim Stadel, UZH

Most of the matter of the universe is of a form unknown to physics. While we don’t know what the identity of the dark matter is, a new insight provided by quantum gravity is helping to drastically narrow down its mass.

February 3, 2021February 6, 2021 by Paul M. Sutter

By Measuring Light From Individual Stars Between Galaxy Clusters, Astronomers Find Clues About Dark Matter

dark matter shown in blue — This image from the NASA/ESA Hubble Space Telescope shows the galaxy cluster MACS J0416. This is one of six clusters that was studied by the Hubble Frontier Fields programme, which yielded the deepest images of gravitational lensing ever made. Scientists used intracluster light (visible in blue) to study the distribution of dark matter within the cluster.

Astronomers have been able to measure an extremely faint glow of light within galaxy clusters, and that measurement came with a surprise: it traced the amount of invisible dark matter, something that scientists have been trying to pin down for decades.

February 3, 2021February 1, 2021 by Paul M. Sutter

A new Class of Exoplanets can Shrink, From Subneptunes Into Superearths

Illustration of the inferred size of the super-Earth CoRoT-7b (center) in comparison with Earth and Neptune. Image Credit: By Aldaron, a.k.a. Aldaron - Own work, incorporating public domain images for reference planets (see below), inspired by Thingg's size comparison, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=8854176

Mighty planets can be whittled down, leaving behind only their rocky cores, becoming nothing bigger than superearths. While astronomers had long suspected that this could happen, a new study reveals that it can occur in as little as a billion years.

February 2, 2021February 1, 2021 by Paul M. Sutter

Physicists Figure out how to Make Gravitational Wave Detectors “Hear” 6x More Universe

This illustration shows the merger of two black holes and the gravitational waves that ripple outward as the black holes spiral toward each other. Could black holes like these (which represent those detected by LIGO on Dec. 26, 2015) collide in the dusty disk around a quasar's supermassive black hole explain gravitational waves, too? Credit: LIGO/T. Pyle — This illustration shows the merger of two supermassive black holes and the gravitational waves that ripple outward as the black holes spiral toward each other. Credit: LIGO/T. Pyle

Gravitational wave detectors are limited by fundamental quantum noise – an incessant “hum” that they cannot ever remove. But now physicists have recently improved a technique, called “squeezing”, that can allow the next generation of detectors to double their sensitivity.

February 2, 2021February 1, 2021 by Paul M. Sutter

Astronomers are Starting to Understand the Quasar Lifecycle

Illustration of an active quasar. New research shows that SMBHs eat rapidly enough to trigger them. Credit: ESO/M. Kornmesser

Supermassive black holes have a complicated lifecycle. Sometimes they’re “on”, blasting out tremendous amounts of energy, and sometimes they’re “off’, where they sleep like dragons in their caves. By comparing the proportion of high-energy to low-energy waves emitted by quasars, astronomers are beginning to pin down how many black holes are sleeping, and when they’re likely to wake back up.

February 1, 2021February 1, 2021 by Paul M. Sutter

Galaxy Mergers can Boost Star Formation, and it can Also Shut it Down

It is known today that merging galaxies play a large role in the evolution of galaxies and the formation of elliptical galaxies in particular. However there are only a few merging systems close enough to be observed in depth. The pair of interacting galaxies picture seen here — known as NGC 3921 — is one of these systems. NGC 3921 — found in the constellation of Ursa Major (The Great Bear) — is an interacting pair of disc galaxies in the late stages of its merger. Observations show that both of the galaxies involved were about the same mass and collided about 700 million years ago. You can see clearly in this image the disturbed morphology, tails and loops characteristic of a post-merger. The clash of galaxies caused a rush of star formation and previous Hubble observations showed over 1000 bright, young star clusters bursting to life at the heart of the galaxy pair.

Galaxy mergers are beautiful sights, but ultimately deadly. In the midst of the collision, the combined galaxy will shine brighter than it ever has before. But that glory comes with a price: all those new stars use up all the available fuel, and star formation grinds to a halt.

February 1, 2021February 1, 2021 by Paul M. Sutter

White Dwarf Atmospheres Might Contain the Pulverized Crusts of Their Dead Planets

Illustration of the internal layers of a white dwarf star. Credit: University of Warwick/Mark Garlick

Astronomers have developed a new technique to search for exoplanets – by looking for their crushed up bones in the atmospheres of white dwarfs. And it’s working.

January 27, 2021January 25, 2021 by Paul M. Sutter

Galileo’s Probe Discovered a Mystery at Jupiter, Juno Finally Helped Solve it

A multitude of magnificent, swirling clouds in Jupiter's dynamic North North Temperate Belt is captured in this image from NASA's Juno spacecraft. Appearing in the scene are several bright-white "pop-up" clouds as well as an anticyclonic storm, known as a white oval. Image Credit: Enhanced Image by Gerald Eichstädt and Sean Doran (CC BY-NC-SA)/NASA/JPL-Caltech/SwRI/MSSS

In 1995, NASA’s Galileo mission dropped a probe into the atmosphere of Jupiter and found it to be far drier than expected. In 2020, NASA’s follow-up mission Juno explained the mystery: it involves mushballs.