Space and astronomy news
In 2019, astronomers observed an unusual gravitational chirp. Known as GW190521, it was the last scream of gravitational waves as a black hole of 66 solar masses merged with a black hole of 85 solar masses to become a 142 solar mass black hole. The data were consistent with all the other black hole mergers we’ve observed. There was just one problem: an 85 solar mass black hole shouldn’t exist.
Continue reading “Building the Black Hole Family Tree”
Some of the most cataclysmic and mysterious events in the cosmos only reveal themselves by their gravitational waves. We’ve detected some of them with our ground-based detectors, but the size of these detectors is limited. The next step forward in gravitational wave (GW) astronomy is a space-based detector: LISA, the Laser Interferometer Space Antenna.
Continue reading “NASA is Building Telescopes for the LISA Mission”
Large galaxies like ours are hosts to Supermassive Black Holes (SMBHs.) They can be so massive that they resist comprehension, with some of them having billions of times more mass than the Sun. Ours, named Sagittarius A* (Sgr A*), is a little more modest at about four million solar masses.
Astrophysicists have studied Sgr A* to learn more about it, including its age. They say it formed about nine billion years ago.
Continue reading “The Milky Way’s Supermassive Black Hole Might Have Formed 9 Billion Years Ago”
In 1974, astronomers Bruce Balick and Robert L. Brown discovered a powerful radio source at the center of the Milky Way galaxy. The source, Sagittarius A*, was subsequently revealed to be a supermassive black hole (SMBH) with a mass of over 4 million Suns. Since then, astronomers have determined that SMBHs reside at the center of all galaxies with highly active central regions known as active galactic nuclei (AGNs) or “quasars.” Despite all we’ve learned, the origin of these massive black holes remains one of the biggest mysteries in astronomy.
The most popular theories are that they may have formed when the Universe was still very young or have grown over time by consuming the matter around them (accretion) and through mergers with other black holes. In recent years, research has shown that when mergers between such massive objects occur, Gravitational Waves (GWs) are released. In a recent study, an international team of astrophysicists proposed a novel method for detecting pairs of SMBHs: analyzing gravitational waves generated by binaries of nearby small stellar black holes.
Continue reading “Scientists Develop a Novel Method for Detecting Supermassive Black Holes: Use Smaller Black Holes!”
Supermassive Black Holes are Nature’s confounding behemoths. It’s difficult for Earth-bound minds to comprehend their magnitude and power. Astrophysicists have spent decades studying them, and they’ve made progress. But one problem still baffles even them: the Final Parsec Problem.
New research might have solved the problem, and dark matter plays a role in the solution.
Continue reading “A Solution to the “Final Parsec Problem?””
What is Dark Matter? That question is prominent in discussions about the nature of the Universe. There are many proposed explanations for dark matter, both within the Standard Model and outside of it.
One proposed component of dark matter is primordial black holes, created in the early Universe without a collapsing star as a progenitor.
Continue reading “Primordial Black Holes Can Only Explain a Fraction of Dark Matter”
Nothing lasts forever, including black holes. Over immensely long periods of time, they evaporate, as will other large objects in the Universe. This is because of Hawking Radiation, named after Stephen Hawking, who developed the idea in the 1970s.
The problem is Hawking Radiation has never been reliably observed.
Continue reading “Merging Black Holes Could Give Astronomers a Way to Detect Hawking Radiation”
Scientists detected the first long-predicted gravitational wave in 2015, and since then, researchers have been hungering for better detectors. But the Earth is warm and seismically noisy, and that will always limit the effectiveness of Earth-based detectors.
Continue reading “Here’s Why We Should Put a Gravitational Wave Observatory on the Moon”
The Universe is filled with supermassive black holes. Almost every galaxy in the cosmos has one, and they are the most well-studied black holes by astronomers. But one thing we still don’t understand is just how they grew so massive so quickly. To answer that, astronomers have to identify lots of black holes in the early Universe, and since they are typically found in merging galaxies, that means astronomers have to identify early galaxies accurately. By hand. But thanks to the power of machine learning, that’s changing.
Continue reading “Black Holes Need Refreshing Cold Gas to Keep Growing”
Humans are born wonderers. We’re always wondering about the next valley over, the next horizon, what we’ll understand next about this vast Universe that we’re all wrapped up in.
In 2015, we finally detected our first long-awaited and long-theorized gravitational wave from the distant merger of two stellar mass black holes. But now we want to know more, and only better detectors can feed our appetite.
Continue reading “Next Generation Gravitational Wave Observatories Could Detect 100-600 Solar Mass Black Hole Mergers”