Universe Today (Page 2)

Gravitational Lens Confirms the Hubble Tension We’ve known the Universe is expanding for a long time. The first solid paper demonstrating cosmic expansion was published by Edwin Hubble in 1929, based on observations made by Vesto Slipher, Milton Humason, and Henrietta Leavitt. Because of this, the rate of cosmic expansion is known as the Hubble constant, or Hubble parameter, H0. From this parameter, you can calculate things such as the age of the Universe since the Big Bang, so knowing the value of H0 is central to our understanding of modern cosmology. Early on, the measured value of the Hubble parameter varied widely. Hubble’s initialRead More →

Could a New Sungrazer Comet Put on a Show at the End of October? Could this be the next great comet? To be sure, these words have been said lots of times before. In a clockwork sky, how comets will perform is always the great wildcard. Comets from Kohoutek to ISON have failed to live up to expectations, while others like W3 Lovejoy took us all by surprise. But a discovery this past weekend has message boards abuzz, as an incoming sungrazer could put on a show right around Halloween. Anatomy of a Sungrazer The discovery comes to us from the prolific Asteroid Terrestrial-impact LastRead More →

Jets From Supermassive Black Holes Create New Stars Along Their Trajectory Since the 1970s, astronomers have observed that supermassive black holes (SMBHs) reside at the centers of most massive galaxies. In some cases, these black holes accelerate gas and dust from their poles, forming relativistic jets that can extend for thousands of light-years. Using the NASA/ESA Hubble Space Telescope, a team of astronomers observed the jet emanating from the center of M87, the supermassive galaxy located 53.5 million light-years away. To their surprise, the team observed nova erupting along the jet’s trajectory, twice as many as they observed in M87 itself. The team was ledRead More →

NASA Turns Off One of Voyager 2’s Science Instruments The two Voyager spacecraft have been speeding through space since 1977, powered by decaying chunks of plutonium that produce less and less energy every year. With less electricity available, NASA has decided to shut down one experiment on Voyager 2, the plasma science instrument. This device measures the quantity and direction of ionized particles passing the spacecraft. While Voyager 2 still has enough electricity to support its four other operational instruments, it will likely be down to just one by the 2030s. NASA said that over the past several years, engineers for the mission have takenRead More →

Bernard’s Star Has a Planet (Again)! The thing about exoplanets is that astronomers don’t see them the way most people think they do. Part of the reason for that is the way we announce them. Whenever an interesting exoplanet is discovered, the press release usually has colorful artwork showing oceans, mountains, and clouds. Something visually captivating like the image above. But the reality is that we have only imaged a few exoplanets directly, and even then, they appear only as small fuzzy blobs. Most of the known exoplanets were discovered by the transit method, where the star dims slightly as the planet passes in frontRead More →

An Earth-like Planet Around a Dead Sun Provides Some Reassurance About the Future of Earth In about five billion years, our Sun will exit its main sequence phase and transition to its red giant phase. At this point, the Sun will expand and consume the planets of the inner Solar System, including Mercury and Venus. What will become of Earth when this happens has been the subject of debate for many decades. But with the recent explosion in exoplanet discoveries, 5,759 confirmed in 4,305 systems so far, astronomers hope to learn more about how planets fare as their stars near the end of their lifeRead More →

Perseverance Finds a Strange Black-and-White Striped Rock on Mars The hits just keep on coming from the Mars Perseverance rover. It’s exploring Jezero Crater on the Red Planet, looking for evidence of microbial life in the planet’s ancient (or even recent) past. Recently it spotted a very strange-looking rock with black and white stripes. Its appearance and location sparked a lot of questions. Perseverance team members have named it “Freya Castle.” From the image, this chunk looks remarkably similar to metamorphic rocks on Earth. The most familiar are gneiss, marble, and schist (to name a few). According to Jeffrey Kargel of the Planetary Science Institute,Read More →

Was the Moon Captured? The general consensus is that Theia crashed into Earth billions of years ago and led to the formation of the Moon. The story doesn’t end there though since there are a few lines of evidence to suggest the Moon could have been captured by the gravitational pull of the Earth instead. The orbit of the Moon is one such observation that leads to a different conclusion for it’s in-line with the plane of the ecliptic rather than the Earth’s equator. A team of researchers have suggested capture theory was the Moon’s origin.  The Giant Impact Theory is by far the mostRead More →

The ESO Releases the Most Detailed Infrared Map of our Galaxy Ever Made Despite decades of large-scale optical surveys, there are still mysteries about the Milky Way galaxy that astronomers are eager to resolve. This is particularly true of its internal structure and the core region, which is difficult to survey due to clouds of gas and dust in the interstellar medium (ISM). This material absorbs visible light, making fainter objects difficult to see in optical wavelengths. Luckily, advances in infrared astronomy have enabled surveys of the Milky Way that have revealed things that would otherwise remain invisible to us. For more than 13 years,Read More →

Stranded Astronauts To Get Their Ride Home You might remember the story of the two astronauts on board the International Space Station that went for an 8 day mission, that was back in June 2024! Butch Wilmore and Suni Williams have been stranded there ever since but their ride home has just arrived at the ISS. A SpaceX Crew Dragon capsule carrying Nick Hague and Aleksandr Gorbunov has just docked so that the two can join the Expedition 72 crew already on board. There are now 11 people on boar the ISS but the Crew-9 capsule will return in February carrying Wilmore and Williams finallyRead More →

An October Annular Solar Eclipse Rounds Out 2024 A remote annular solar eclipse bookends the final eclipse season for 2024. The final eclipse of the year is almost upon us. If skies are clear, a few lucky observers and intrepid eclipse-chasers will get to witness the passage of the Moon in front of the Sun one last time on Wednesday, October 2nd during an annular solar eclipse. The eclipse is the final one of the current season, and the last solar eclipse for 2024. The first—the April 8th total solar eclipse spanning North America—was witnessed by millions. This week’s eclipse is by contrast much moreRead More →

Nuclear Detonations Could Deflect Dangerous Asteroids Away from Earth Before you read the rest of this article know there are no known threats to life on Earth! We shouldn’t sit complacently on this tiny rock in space though so NASA have been working on ways to neutralise potential asteroid threats should they arise. The DART mission proved it was possible to alter the trajectory of an asteroid in space. Direct impact though where a probe smashes into the rock is one way but potentially not the best. A team of researchers have now been exploring ways that a nuclear explosion near an asteroid may sendRead More →

Unloading Cargo on the Moon I don’t think it’s something I have ever really thought of! Robotic explorers can travel around the Solar System visiting our neighbouring planets but when they arrive, sometimes a scientific package must be deployed to the surface. Never occurred to me just how that’s achieved! With a number of landers scheduled to visit the Moon, NASA are testing a new robotic arm called the Lightweight Surface Manipulation System AutoNomy capabilities Development for Surface Operations or LANDO for short! It will lift payloads off the lander and pop them down gently on the surface of the Moon.  The Moon has alwaysRead More →

How Does the Milky Way Compare to Other Galaxies? The Milky Way is special because it is our home. No matter where we are on Earth we can see its arc of light overhead if the night is dark enough. But how similar is our galaxy to others? Is it an unusual spiral galaxy, or is it rather typical in the cosmos? Before we had discovered exoplanets, astronomers generally thought our solar system was rather typical. Sure, there would be differences, but the general arrangement of rocky worlds close to the Sun and cold gas giants in the outer system made sense. However when weRead More →

Space Perspective Completes a Test Flight, Sending a Balloon to 30 km It’s great to see so many private organisations entering the space sector. Space Perspective are another and they have just completed a successful uncrewed capsule ascent to an altitude of 30km. Their Neptune-Excelsior capsule was carried by a balloon and landed in the ocean 6 hours later. It was able to maintain its cabin pressure and stability throughout the flight proving that it met the requirements for future passenger flights starting in 2025.  Space Perspective was founded in 2019 by Jane Poynter and Taber MacCallum. Their focus in the sector is space tourismRead More →

We Don’t See Many Planets in Old Triple Star Systems Why is it important to search for exoplanets in triple star systems and how many can we find there? This is what a recent study accepted by Astrophysics & Space Science hopes to address as a pair of researchers from the University of Texas at Arlington investigated the statistical likelihood of triple star systems hosting exoplanets. This study holds the potential to help researchers better understand the formation and evolution of triple star systems and whether they are suitable to find life as we know it. Here, Universe Today discusses this incredible research with Dr.Read More →

Martian Clay Could Be Hiding the Planet’s Atmosphere Ages ago in its youth, Mars appeared much like Earth. It was a warm planet with lakes, rivers, and vast seas. It had a thick atmosphere with clouds and rain. One major difference is that the atmosphere was rich with carbon dioxide instead of oxygen. Then about 3.5 billion years ago much of the atmosphere disappeared, and we haven’t understood how. A new study in Science Advances suggests that the waters of Mars may have been the key, and much of the ancient atmosphere may be locked in the surface of the red planet. The authors centerRead More →

Astronomers Find a Strange Lopsided Planet I’ve often stated that planets come in a wide range of sizes but rarely do I find myself stating they come in a wide range of shapes too! The discovery of WASP-107b is a case  in point since this planet is the size of Jupiter but only a tenth of its mass. But there’s more… Using the James Webb Space Telescope a team of astronomers have accurately identified that the planet has an east-west asymmetry in its atmosphere, in other words, it’s lopsided. It is tidally locked to the star and on one side, the atmosphere seems to beRead More →

Another Building Block of Life Can Handle Venus’ Sulphuric Acid Venus is often described as a hellscape. The surface temperature breaches the melting point of lead, and though its atmosphere is dominated by carbon dioxide, it contains enough sulfuric acid to satisfy the comparison with Hades. But conditions throughout Venus’ ample atmosphere aren’t uniform. There are locations where some of life’s building blocks could resist the planet’s inhospitable nature. Among the rocky planets, Venus has by far the largest atmosphere by volume. So, while its surface is inhospitable, its atmosphere has regions that are the most Earth-like of anywhere else in the Solar System. ScientistsRead More →

Dark Matter Could a Have Slight Interaction With Regular Matter The reason we call dark matter dark isn’t because it’s some shadowy material. It’s because dark matter doesn’t interact with light. The difference is subtle, but important. Regular matter can be dark because it absorbs light. It’s why, for example, we can see the shadow of molecular clouds against the scattered stars of the Milky Way. This is possible because light and matter have a way to connect. Light is an electromagnetic wave, and atoms contain electrically charged electrons and protons, so matter can emit, absorb and scatter light. Dark matter isn’t electrically charged. ItRead More →