Universe Today

November 1, 2024November 1, 2024 by Mark Thompson

The Connection Between Black Holes and Dark Energy is Getting Stronger

JWST NIRCam imaging of star-forming protocluster PHz G191.24+62.04, 11 billion years ago as the universe was approaching the peak of star formation. These early galaxies are among the most active star-forming galaxies observed between 10.5 and 11.5 billion years ago. Each galaxy seen in this image is therefore producing many black holes, which are converting matter into dark energy according to the cosmologically coupled black hole hypothesis. This image shows the two "modules" of JWST NIRCam: The leftmost module contains the protocluster, and the rightmost module is an adjacent blank field. Each module sees thousands of galaxies.

The discovery of the accelerated expansion of the Universe has often been attributed to the force known as dark energy. An intriguing new theory was put forward last year to explain this mysterious force; black holes could be the cause of dark energy! The theory goes on to suggest as more black holes form in the Universe, the stronger the pressure from dark energy. A survey from the Dark Energy Spectroscopic Instrument (DESI) seems to support the theory. The data from the first year of operation shows the density of dark energy increases over time and seems to correlate with the number and mass of black holes!

November 1, 2024November 1, 2024 by Brian Koberlein

Will Advanced Civilizations Build Habitable Planets or Dyson Spheres

Artist's impression of the terraforming of Mars, from its current state to a livable world. Credit: Daein Ballard

If there are alien civilizations in the Universe, some of them could be super advanced. So advanced that they can rip apart planets and create vast shells surrounding a star to capture all its energy. These Dyson spheres should be detectable by modern telescopes. Occasionally astronomers find an object that resembles such an alien megastructure, but so far, they’ve all turned out to be natural objects. As best we can tell, there are no Dyson spheres out there.

October 31, 2024October 31, 2024 by Evan Gough

This is What it Sounds Like When the Earth’s Poles Flip

Ever wondered what a geomagnetic excursion sounds like? The ESA does. Image Credit: ESA

Is there something strange and alien confined deep inside the Earth? Is it trying to break free and escape into the heavens? No, of course not.

But in a new soundscape from the ESA, it sure sounds like it.

October 31, 2024October 31, 2024 by Matt Williams

Orbital Debris is Getting Out of Control

The destruction of a single satellite could be catastrophic for our orbital endeavours. Image Credit: ESA

In 1978, NASA scientists Donald J. Kessler and Burton G. Cour-Palais proposed a scenario where the density of objects in Low Earth Orbit (LEO) would be high enough that collisions between objects would cause a cascade effect. In short, these collisions would create debris that would result in more collisions, more debris, and so on. This came to be known as the Kessler Syndrome, something astronomers, scientists, and space environmentalists have feared for many decades. In recent years, and with the deployment of more satellites than ever, the warning signs have become undeniable.

Currently, there is an estimated 13,000 metric tons (14,330 US tons) of “space junk” in LEO. With the breakup and another satellite in orbit – the Intelsat 33e satellite – the situation will only get worse. This broadband communications satellite was positioned about 35,000 km (21,750 mi) above the Indian Ocean in a geostationary orbit (GSO). According to initial reports issued on October 20th, the Intelsat 33e satellite experienced a sudden power loss. Hours later, the U.S. Space Forces (USSF) confirmed that the satellite appeared to have broken up into at least 20 pieces.

October 31, 2024October 31, 2024 by Evan Gough

Webb Reveals a Steam World Planet Orbiting a Red Dwarf

An artist’s conception of the “steam world” GJ 9827 d, shown in the foreground in blue. Astronomers have theorized about these worlds, but this is the first one they've observed. Image credit: NASA, ESA, Leah Hustak (STScI), Ralf Crawford (STScI)

The JWST has found an exoplanet unlike any other. This unique world has an atmosphere almost entirely composed of water vapour. Astronomers have theorized about these types of planets, but this is the first observational confirmation.

October 31, 2024October 31, 2024 by Nancy Atkinson

NASA Wants to Move Heavy Cargo on the Moon

Illustration of logistics elements on the lunar surface. Credit: NASA

While new rockets and human missions to the Moon are in the press, NASA is quietly thinking through the nuts and bolts of a long-term presence on the Moon. They have already released two white papers about the lunar logistics they’ll require in the future and are now requesting proposals from companies to supply some serious cargo transportation. But this isn’t just for space transport; NASA is also looking for ground transportation on the Moon that can move cargo weighing as much as 2,000 to 6,000 kg (4,400 to 13,000 pounds.)

October 31, 2024October 31, 2024 by Brian Koberlein

Learning More About Supernovae Through Stardust

Illustration of Supernova 1987A based on observations by ALMA. Credit: Alexandra Angelich (NRAO/AUI/NSF)

Most of the diverse elements in the Universe come from supernovae. We are, quite literally, made of the dust of those long-dead stars and other astrophysical processes. But the details of how it all comes about are something astronomers strive to understand. How do the various isotopes produced by supernovae drive the evolution of planetary systems? Of the various types of supernovae, which play the largest role in creating the elemental abundances we see today? One way astronomers can study these questions is to look at presolar grains.

October 31, 2024October 31, 2024 by Brian Koberlein

Astronomers Predict the Orbits of Potentially Hazardous Comets From Meteor Showers

Comets have long been seen as omens and portents, and it’s easy to understand why. They first appear as faint smudges of light in the sky, sometimes fading soon after and sometimes becoming brighter than the planets, with a long, glowing tail. They have been observed throughout human history, but it wasn’t until the eighteenth century that astronomers began to predict the return of some comets. Even today, we can’t predict the return of most comets until after they swing through the inner solar system. If such a comet happens to be heading toward Earth, we wouldn’t know about it until too late. But that could change thanks to our observations of meteor showers.

October 31, 2024October 31, 2024 by David Dickinson

Amazing Reader Views of Comet A3 Tsuchinshan-ATLAS From Around the World

Comet T-ATLAS — Comet A3 Tsuchinshan- ATLAS on September 28th, over the McMath-Pierce Solar Telescope at Kitt Peak, Arizona. Credit: Rob Sparks.

Comet C/2023 A3 Tsuchinshan-ATLAS survived perihelion to become a fine dusk object for northern hemisphere observers.

It was an amazing month for astronomy. Not only were we treated to an amazing second solar storm for 2024 that sent aurorae as far south as the Caribbean, but we had a fine naked eye comet: C/2023 A3 Tsuchinshan-ATLAS.

October 31, 2024October 31, 2024 by Nancy Atkinson

Astronomer Calculates When van Gogh Painted This

van Gogh's 'Lane of Poplars at Sunset' painting. Image courtesy Texas State University.

One of my favorite paintings is Starry Night by Vincent van Gogh — for obvious astronomical reasons. But another favorite of van Gogh’s works is Lane of Poplars at Sunset. This painting depicts the setting Sun perfectly aligned with a long lane of trees, casting long shadows.

The geometry of the Earth and Sun means that this scene had to be painted on one specific day of the year when the alignment would be possible. An astronomer has now used 19th-century maps to discover where the lane was, and then used astronomical calculations to determine which date the Sun would be in the exact position as the painting. His result? The painting depicts a stretch of road known as Weverstraat in the Dutch town of Nuenen, on November 13 or 14, 1884.