fraser

fraser, 2 hours ago to random

New images from NASA's Chandra X-Ray Observatory show a vent of hot gas blowing away from the center of the Milky Way. The region is located about 26,000 light-years from Earth, starts at the center of the galaxy, and is perpendicular to the Milky Way's spiral disk, extending for hundreds of light-years. Astronomers think the vent formed as hot gas forced away from the center of the galaxy collided with cooler gas lying in its path, creating shockwaves.

https://chandra.si.edu/press/24_releases/press_050924.html

fraser, 3 hours ago to random

The world's most powerful telescopes could observe Earth-sized worlds orbiting other stars. The problem is that the star's glare is so bright it overwhelms the fainter planet. When the next generation Habitable Worlds Observatory is built, it will need to be able to dim the starlight by 10 billion, revealing the planets around it. A new paper discusses the various strategies developed to achieve this starlight suppression, from coronographs to starshades.

https://arxiv.org/abs/2404.18036

fraser, 3 hours ago to random

Astrobiologists continue to examine different exoplanet atmospheres, searching for a mix of chemicals that would provide a strong signal for life in another world. Here on Earth, ozone forms through the photolysis of molecular oxygen and indicates life. But there are abiotic processes that can create ozone as well. JWST is searching for planets in the habitable zones of red dwarf stars, and the presence of ozone should impact their climates.

https://arxiv.org/abs/2404.17972

fraser, 2 days ago to random

Astronomers have discovered a fascinating new exoplanet, unlike anything in the Solar System. The planet was found in the binary star system TOI 4633, orbiting one of the stars within the habitable zone. Designated TOI 4633 c, the planet is a mini-neptune, taking 272 days to orbit around its star. Although the planet itself isn't habitable, it could have one or more large moons that could have life—like Endor or Pandora from science fiction.

https://science.nasa.gov/universe/exoplanets/discovery-alert-mini-neptune-in-double-star-system-is-a-planetary-puzzle/

fraser, 2 days ago to random

When NASA's New Horizons mission flew past Pluto, it discovered a dramatically more active world than astronomers expected. It had mountains of ice, glaciers of nitrogen, and evidence of cryovolcanoes. Researchers have been studying the archival data from New Horizons and built mathematical models that explain the cracks and bulges in the ice covering Pluto's Sputnik Platina Basin. Their calculations suggest a liquid ocean is 40-80 km beneath the ice.

https://phys.org/news/2024-05-peering-pluto-ocean-mathematical-images.html

fraser, 2 days ago to random

A new telescope has come online to observe satellites and stars around the clock, even in full daylight. The Huntsman Telescope comprises ten consumer-level 400 mm Canon lenses working together. It was originally designed for night sky observations, but researchers have found that broadband filters can block most daylight while allowing specific wavelengths from space to pass through. This could allow continuous observations of stars close to the Sun.

https://lighthouse.mq.edu.au/article/may-2024/stargazing-in-broad-daylight-how-a-multi-lens-telescope-is-changing-astronomy

fraser, 2 days ago to random

Although astronomers have discovered thousands of exoplanets, none are truly like our home planet: an Earth-sized world orbiting a Sun-like star in the habitable zone. A new paper suggests that the radial velocity method for discovering exoplanets should be able to find Earth-mass worlds around relatively close Sun-like stars using a deep learning algorithm. They injected the signal of an exo-earth into an existing observation and teased out the subtle signal.

https://arxiv.org/abs/2405.13247

fraser, 2 days ago to random

Astronomers recently reported the discovery of seven stars as potential candidate Dyson spheres. These stars give off most of their radiation in the infrared, potentially the waste heat from a sphere or swarm of spacecraft around a star. A new paper has another explanation: dust-obscured galaxies. These are a rare type of quasar billions of light-years away that emit enormous amounts of radiation, but it's obscured by dust, so it's largely infrared.

https://arxiv.org/abs/2405.14921

fraser, 2 days ago to random

While text and images are all the rage for generative AI, there are some interesting science applications. Astronomical surveys generate millions and even billions of observations that can be fed into a data-hungry transformer model and used to make fascinating discoveries. Researchers have developed a new transformer model called AstroPT that was trained on 2.1 billion images from the DESI Legacy Survey. This model can then predict the structures of missing data.

https://arxiv.org/abs/2405.14930

fraser, 2 days ago to random

Venus has many volcanoes, but it was long believed that they were dormant and that no active volcanism existed on the planet's surface. A detailed look through archived data from NASA's Magellan mission has revealed that two volcanoes were recorded erupting. Between 1990 and 1992, Magellan mapped 98% of the surface of Venus. By comparing two scans of the same area, researchers discovered outflows of molten rock filling a vent crater. Active volcanism!

https://www.jpl.nasa.gov/news/ongoing-venus-volcanic-activity-discovered-with-nasas-magellan-data

fraser, 5 days ago to random

Astronomers have known about free-floating planets in the Orion Nebula for over a decade. Hubble first discovered them, and then hundreds more were found by JWST. New observations by the Euclid mission have also found dozens of rogue planets in the Orion Nebula, about 1,500 light-years away. These are larger than JWST's discoveries, at least four times as big as Jupiter, and are only 3 million years old, glowing in the infrared from their recent formation.

https://arxiv.org/abs/2405.13497

fraser, 5 days ago to random

NASA's long-term plan is to build a research station on the Moon, permanently inhabited by astronauts. If it's located near the south lunar pole, the station will have access to water ice for drinking water, oxygen production, and food growing. Assuming ideal water conservation and recycling, how much water will they need? A new paper analyzed the water needs for a station of 100 people, estimating how much is needed for human, agricultural, and technical uses.

https://arxiv.org/abs/2405.14100

fraser, 5 days ago to random

With thousands of Starlink satellites in orbit, astronomers are starting to get a handle on their impact on astronomy, especially during dawn and twilight - invisible with the unaided eye but leaving a trail through long-explore images. Pilots have noticed that Starlinks can be surprisingly bright near the horizon when the sunlight glints off them perfectly. According to a new paper, one Starlink flare was almost as bright as Venus and recorded as a UAP sighting.

https://arxiv.org/abs/2405.13091

fraser, 5 days ago to random

Astronomers working with TESS have released a huge catalog of 126 new exoplanets. The results contain thousands of radial velocity measurements from the Keck Observatory that confirm the initial discoveries by TESS. There are the typical hot-jupiters and super-earths, but also some strange worlds like superdense sub-neptunes and hot-super-earths. This new catalog gives astronomers a better sense of the various exoplanets that can appear in the Milky Way.

https://www.keckobservatory.org/tess-keck-survey/

fraser, 6 days ago to random

Another large iceberg broke off this week from the Brunt Ice Shelf in Antarctica. Designated A-83, this iceberg measures 380 square kilometers across and is roughly triangle-shaped. Scientists use thermal imaging data to track the thickness of the ice under the Brunt Ice Shelf, revealing the exact spot of the calving line. This image was provided by ESA's Copernicus Sentinel-1 mission, which can track ice changes, even during the Antarctic Winter.

https://www.esa.int/ESA_Multimedia/Images/2024/05/Iceberg_A-83_breaks_free

fraser, 6 days ago to random

The orientation of the Sun's magnetic field follows an 11-year cycle, reversing the polarity of its poles. Astronomers have always assumed that the source of the Sun's magnetic field was deep down inside the star, with churning hydrogen generating its stellar dynamo. New research suggests the Sun's outermost layers could cause the magnetic field. Minor changes in plasma flow near the surface can explain the magnetic fields and sunspots.

https://news.mit.edu/2024/suns-magnetic-field-origin-could-lie-close-to-its-surface-0522

fraser, 6 days ago to random

Over the last 70 years, astronomers have charted the disappearance of hundreds of massive stars from the night sky. These kinds of stars should be detonating as supernovae, but instead, they've just vanished. The evidence is growing that some of these stars are imploding into black holes without a peep. A new paper charts the behavior of the star VFTS 243, a main sequence star with a black hole companion that probably suffered a complete collapse.

https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.132.191403

fraser, 6 days ago to random

New observations of supermassive black holes show that they release intense beams of particles into space from their highly magnetic accretion disks. Data from the Chandra X-Ray Observatory show the remnants from older beams pointing in completely different directions. These beams can have a big impact on galaxies in the target zone. Some can be enriched with heavier elements, while others can have their star formation shut down.

https://chandra.si.edu/press/24_releases/press_052224.html

fraser, 6 days ago to random

Astronomers have developed a new technique to measure the rate at which a supermassive black hole rotates. They used a recent tidal disruption event, which shredded a star into chunks, adding them to its accretion disk. This created a wobble in the disk, releasing a regular pattern of X-ray flashes that provided a way to measure the rotation rate. They found it's turning at less than 25% the speed of light, which is surprisingly slow for a supermassive black hole.

https://news.mit.edu/2024/using-wobbling-stellar-material-astronomers-measure-supermassive-black-hole-spin-0522

fraser, 6 days ago to random

Astronomers using NASA's TESS mission have discovered a terrestrial planet orbiting the red dwarf star Gliese 12, which is only 40 light-years away. Their initial estimates calculate that the planet is a little larger than Venus but smaller than Earth, receiving about as much radiation from its star as Venus does from the Sun. This puts it at the inner edge of the star's habitable zone. The next step is to discover if the planet has an atmosphere.

https://science.nasa.gov/universe/exoplanets/nasas-tess-finds-intriguing-world-sized-between-earth-venus/

fraser, 6 days ago to random

ESA's Euclid mission has scanned the skies for months, building a map of the Universe's large-scale structures. Today, the agency released five images that showcase its Early Release Observations, which targeted 17 astronomical objects, from nearby nebulae to more distant galaxies. Because Euclid is in space, its images are four times sharper than ground-based observations. Its early catalog contains 11 million objects in visible light and 5 million in infrared.

https://www.esa.int/Science_Exploration/Space_Science/Euclid/ESA_s_Euclid_celebrates_first_science_with_sparkling_cosmic_views

fraser, 7 days ago to random

While JWST is revolutionizing near-infrared astronomy, there's a gap in far-infrared space telescopes. Astronomers hope to observe those wavelengths again with a new mission called the Single Aperture Large Telescope for Universe Studies (SALTUS). This would be an off-axis far-infrared telescope with a 14-meter off-axis primary reflector. Like JWST, it would use a sunshield to keep its instruments cold, allowing it to see early into the Universe and search for life.

https://arxiv.org/abs/2405.12829

fraser, 7 days ago to random

The late astrophysicist Stephen Hawking theorized that black holes should evaporate over vast periods, eventually disappearing completely. However, the decay rate is so slow that the process has never been directly observed. In a new paper, astronomers propose that mergers between black holes could throw out asteroid-mass mini-black holes, which would evaporate rapidly, providing an opportunity to detect black hole evaporation and prove Hawking's prediction.

https://arxiv.org/abs/2405.12880

fraser, 7 days ago to random

On May 18th, a meteor traveling at over 44 km/s lit up the skies over Spain and Portugal. Many ground observers caught the fireball, which lit up the surrounding landscape like a bright flare. ESA's Meteosat weather satellite, 36,000 km away, was watching the region from its geostationary orbit and also noticed the fireball. The observations were made with the satellite's Lightning Imager instrument, tracking lightning activity in Europe since 2022.

https://www.esa.int/Applications/Observing_the_Earth/Meteorological_missions/meteosat_third_generation/Fireball_witnessed_by_weather_satellite

While a meteor lit up the skies over Spain and Portugal recently, it was also captured by the Meteosat Third Generation Imager weather satellite hovering 36,000 km away in geostationary orbit.