Universe Today

August 10, 2024August 10, 2024 by Carolyn Collins Petersen

Gaia Finds Hundreds of Asteroid Moons

This illustrates the orbits of more than 150,000 asteroids seen by Gaia as part of its data release 3. The orbits shown here extend from the inner solar system to the orbit of Jupiter. Courtesy ESA/Gaia/DPAC; CC BY-SA 3.0 IGO

The amazing Gaia mission to chart stars in the Milky Way Galaxy is also an expert asteroid hunter. Now, astronomers are reporting its success at spotting more moons of asteroids in our solar system. Once the Gaia data from its release 3 are confirmed, those observations will add 352 more binary asteroids to the known count. That nearly doubles the known number of asteroids with moons and previous Gaia data releases also revealed asteroids in its survey.

August 9, 2024August 9, 2024 by Evan Gough

The JWST Reveals the Nature of Dust Around an Active Galactic Nuclei

The James Webb Space Telescope captured this three colour image of the galaxy ESO 428-G14. New research shows how the dust near the galaxy's supermassive black hole is heated up. Image Credit: NASA, ESA, CSA, and STScI

Supermassive Black Holes (SMBHs) are located in the centers of large galaxies like ours. When they’re actively feeding, they produce more light and are called active galactic nuclei (AGN). But their details are difficult to observe clearly because large clouds of gas block our view.

The JWST was built just for circumstances like these.

August 8, 2024August 8, 2024 by Evan Gough

The Aftermath of Neutron Star Mergers

An artistic rendering of two neutron stars merging. Credit: NSF/LIGO/Sonoma State/A. Simonnet

Neutron stars (NS) are the collapsed cores of supermassive giant stars that contain between 10 and 25 solar masses. Aside from black holes, they are the densest objects in the Universe. Their journey from a main sequence star to a collapsed stellar remnant is a fascinating scientific story.

Sometimes, a binary pair of NS will merge, and what happens then is equally as fascinating.

August 7, 2024August 9, 2024 by Matt Williams

New Study Suggests that Our Galaxy is Crowded or Empty. Both are Equally Terrifying!

Gaia's all-sky view of our Milky Way Galaxy and neighbouring galaxies, based on measurements of nearly 1.7 billion stars. The map shows the total brightness and colour of stars observed by the ESA satellite in each portion of the sky between July 2014 and May 2016. Brighter regions indicate denser concentrations of especially bright stars, while darker regions correspond to patches of the sky where fewer bright stars are observed. The colour representation is obtained by combining the total amount of light with the amount of blue and red light recorded by Gaia in each patch of the sky. The bright horizontal structure that dominates the image is the Galactic plane, the flattened disc that hosts most of the stars in our home Galaxy. In the middle of the image, the Galactic centre appears vivid and teeming with stars. More information on: http://sci.esa.int/gaia/60169-gaia-s-sky-in-colour/

Is there intelligent life in the Universe? And if so, just how common is it? Or perhaps the question should be, what are the odds that those engaged in the Search for Extraterrestrial Intelligence (SETI) will encounter it someday? For decades, scientists have hotly debated this topic, and no shortage of ink has been spilled on the subject. From the many papers and studies that have been written on the subject, two main camps have emerged: those who believe life is common in our galaxy (aka. SETI Optimists) and those who maintain that extraterrestrial intelligence is either rare or non-existent (SETI Pessimists).

In a recent paper, David Kipping (Prof. “Cool Worlds” himself) and Geraint Lewis examined this debate more closely and offered a fresh take based on a form of probability analysis known as Jayne’s Experiment. By applying this method to astrobiology and the Drake Equation, they concluded that the existence of intelligent life in our galaxy may be an “all or nothing” proposition. To quote the late and great scientist and science fiction author Arthur C. Clarke: “Two possibilities exist: either we are alone in the Universe, or we are not. Both are equally terrifying.”

August 7, 2024August 7, 2024 by Evan Gough

Scientists Discover New Geological Link Between Earth and Venus

Ishtar Terra is a complex geological region on Venus. New research shows it may have formed through processes similar to Earth's. Image Credit: NASA/JPL/USGS – http://photojournal.jpl.nasa.gov/catalog/PIA00007, Public Domain, https://commons.wikimedia.org/w/index.php?curid=18235544

Venus is sometimes called Earth’s sister planet because of their shared physical, geological, and atmospheric features. Scientists have discovered something new about Venus’ geology that’s reminding us of the similarities between the two planets. We have to look deep inside both planets to see what the researchers found.

August 7, 2024August 7, 2024 by Carolyn Collins Petersen

The Moon’s Atmosphere Comes from Space Weathering

A future astronaut studies the lunar surface to understand space weathering of the Moon. Courtesy NASA.

How do you get an atmosphere at a world that doesn’t have one and can’t keep one? If it’s the Moon, you simply bombard it for millions of years with tiny meteorites. Also, let it sit in the solar wind and see what happens. Both space-weathering processes create a thin “exosphere” just above the lunar surface.

August 7, 2024August 7, 2024 by Mark Thompson

How a Black Hole Could Eat a Neutron Star from the Inside Out

Illustration of a neutron star. Credit: ESA

Primordial black holes are thought to have formed early in the evolution of the universe. None have been discovered yet but if they do exist and they may be plentiful, drifting almost invisibly through the cosmos, then they might account for dark matter. One possible way to search for them is to see the results of their meals and a bizarre new theory suggests low mass black holes could be captured by neutron stars and become trapped inside, devouring them from within. If these strange objects existed then it would make neutron stars less common in locations where black holes would proliferate as observed around Galactic centre.

August 6, 2024August 6, 2024 by Mark Thompson

If Advanced Civilizations Using Quantum Communications, Is That Why We’ve Never Seen Them?

Establishing communication with an alien intelligence is one of the news items I, and I’m sure many others, long to see. Since we have started the search for advanced civilisations we have tried numerous ways to detect their transmissions but to date, unsuccessfully. A new paper suggests quantum communication may be the ideal method for interstellar communication. It has many benefits but the challenge is that it would require a receiver over 100km across to pick up a signal. Alas they know we don’t have that tech yet!

August 6, 2024August 6, 2024 by Matt Williams

Elliptical Orbits Could be Essential to the Habitability of Rocky Planets

Illustration of Kepler-186f, a recently-discovered, possibly Earthlike exoplanet that could be a host to life. (NASA Ames, SETI Institute, JPL-Caltech, T. Pyle) — This is Kepler 186f, an exoplanet in the habitable zone around a red dwarf. We've found many planets in their stars' habitable zones where they could potentially have surface water. But it's a fairly crude understanding of true habitability. Image Credit: NASA Ames, SETI Institute, JPL-Caltech, T. Pyle)

A seismic shift occurred in astronomy during the Scientific Revolution, beginning with 16th-century polymath Copernicus and his proposal that the Earth revolved around the Sun. By the 17th century, famed engineer and astronomer Galileo Galilei refined Copernicus’ heliocentric model using observations made with telescopes he built himself. However, it was not until Kepler’s observations that the planets followed elliptical orbits around the Sun (rather than circular orbits) that astronomical models matched observations of the heavens completely.

As it turns out, this very quirk of orbital mechanics may be essential to the emergence of life on planets like Earth. That was the hypothesis put forth in a recent study by a team of astronomers led by the University of Leeds. According to their work, orbital eccentricity (how much a planet’s orbit deviates from a circle) can influence a planet’s climate response, which could have a profound effect on its potential habitability. These findings could be significant for exoplanet researchers as they continue to search for Earth-like planets that could support life.

August 6, 2024August 6, 2024 by David Dickinson

2024 Perseids Light Up the August Sky

That ‘Old Faithful’ of meteor showers the Perseids peak early next week.

Great ready for one of the surefire astronomical events of 2024, as the peak for the Perseid meteors arrives next week.

To be sure, the Perseids aren’t the most intense annual meteor shower of the year; in the first half of the 20^th century, that title now goes to the December Geminids. What the Perseids do have going for them is timing: they typically arrive in early August, before the academic year starts and during prime camping season, which finds lots of folks out under warm summer skies.