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A special spacecraft will guide the space station through Earth’s atmosphere, but what about other large pieces of space debris?

We cover a 3.26-billion-year-old meteorite impact, the spread of bird flu and a scurvy case study that serves as a cautionary tale in this week’s news roundup.

The tails of Comet Tsuchinshan-ATLAS were a sight to behold.

Walt Disney Studios and Pixar are returning to animated outer space with sci-fi adventure comedy "Elio."

Soil-like pebbles in moon samples brought home by Apollo 16 astronauts have revealed new details about lunar history.

A recent satellite image captured the reemergence of a unique, UFO-like cloud, known as the "Taieri Pet," which appears above New Zealand's South Island when conditions are just right.

NASA Europa Clipper mission is on its way to Europa, but it has some stops to make before it investigates the habitability of the icy ocean moon of Jupiter, including a Mars trip and a brief return to Earth.

To northern sky watchers, Vega is a familiar sight in the summer sky. It’s one of the brightest stars in the sky and in 2013, astronomers detected a large ring of rocky debris surrounding the planet. The prospect of planets suddenly became a real possibility so astronomers turned the James Webb Space Telescope (JWST) on the star. The hunt achieved 10 times the sensitivity of previous ground based searches but alas no planets were discovered. 

Vega lies in the constellation Lyra and is one of the prominent stars that makes up the Summer Triangle along with Aquila in Altair and Deneb in Cygnus. Vega itself likes 25 light years away from Earth so it is, in astronomical terms, relatively close. It’s a hot blue/white star which has a visible surface temperature of around 9,600 degrees. At this temperature it is hotter than the Sun and in size it is about 2.1 times larger in diameter. 

The track of the ISS near Vega in Lyra. From right to left, the station is passing from sunlight into Earth’s shadow. Its color transitions from white to red. Credit: Bob King

Data captured by JWST has recently been used to study Vega. The space telescope is perhaps the most advanced telescope to be placed into orbit. It was launched in December 2021 as part of a partnership between NASA, the European Space Agency (ESA) and the Canadian Space Agency (CSA.) It orbits the Sun at the second Lagrange point which is about 1.5 million km away from Earth. As telescopes go it’s not the largest (main mirror is 6.5m across) but by being in space it can out perform many ground-based instruments. 

Among the many instruments on board JWST, NIRCam (Near Infrared Camera) and MIRI (Mid Infrared Camera) have been used to probe the secrets of Vega. Interest was piqued when the Infrared Astronomical Satellite (IRAS) detected an excess of long wavelengths which were attributed to a cold dust ring emitting radiation at 25-100 ?m. Further studies revealed the signal was very similar to the signal from the Kuiper Belt. The discovery led astronomers to the conclusion that it must be the remains of planetary formation. 

MIRI, ( Mid InfraRed Instrument ), flight instrument for the James Webb Space Telescope, JWST, during ambient temperature alignment testing in RAL Space’s clean rooms at STFC’s Rutherford Appleton Laboratory, 8th November 2010.

In a paper written by a team of astronomers led by Charles Beichman from NASA’s Exoplanet Science Institute they describe their attempts to hunt down planets in the ring of debris. They were able to utilise data from NIRCam’s coronographic observations of Vega. Within this data, there were 3 sources identified and analysed using supporting data from MIRI. The sources were assessed to see if astrometric data confirmed an association with Vega. If it were part of the Vega system the data would indicate a mass of these sources between 1 and 3 times mass of Jupiter and a temperature in the region of 250K.

Such an object is likely to have disrupted the smooth disk structure but the MIRI data reveals no such effects. It seems then for now at least, that the debris field around Vega is devoid of evidence of planetary formation. Further studies using the instrumentation on board JWST and other new observatories coming on line may change this view but for now it seems, Vega may just be alone without any planetary system. 

Source : Searching for Planets Orbiting Vega with the James Webb Space Telescope

The post Webb Scans Vega for Planets appeared first on Universe Today.

The TRAPPIST-1 system is a science-fiction writer’s dream. Seven Earth-sized worlds orbit a red dwarf star just 40 light-years away. Three of those worlds are within the habitable zone of the star. The system spans a distance less than 25 times that of the distance from the Earth to the Moon. Oh, what epic tales a TRAPPIST civilization would have! That is, if life in such a system is even possible…

Therein lies the problem. Although the vast majority of potentially habitable worlds orbit red dwarf stars, that doesn’t mean most inhabited worlds have a red dwarf sun. Red dwarfs are known to be violently active in their youth. They emit powerful flares that might strip nearby planets of their atmospheres, and even if a planet can hold on to its sky, it would still be bathed in powerful radiation. Only when a red dwarf matures is it calm and stable. This is very different from larger stars such as our Sun, which are reasonably calm throughout their lives. Since potentially habitable red dwarf planets must orbit very close to their stars, there is a worry that even in the best conditions, life on such a world could never get a foothold. The environment is just too harsh. But a new study gives exobiologists some surprising hope.

The study focuses on red dwarf superflares and the radiation they emit. These flares emit a great amount of x-rays and ultraviolet radiation. For a young red dwarf planet with an atmosphere, most of the x-rays would never reach the surface, but the young world would still be bathed in UV radiation. The team wanted to know how hostile that UV would be to early life, so they bathed microbes in UV.

The study looked at two types of bacteria. Deinococcus radiodurans is a variety known to be UV tolerant, while Escherichia coli is known to be susceptible to radiation. They bathed each variety in ultraviolet radiation levels that would be typical at the distances of the TRAPPIST worlds e, f, and g, which are the most potentially habitable. The results weren’t good for the E. coli variant, as a simulated flare sterilized them below the limit of detection for the innermost world and some survival for the most distant one. But the D. radiodurans did fairly well. Only about 1 in 600 million survived a simulated flare for the closest world, but given the typical time span between flares, the bacteria would maintain a foothold. And, of course, with regular flares, there would be an evolutionary pressure to become more UV resistant.

So it seems that while early life in the TRAPPIST system might have a tough evolutionary road, the superflares wouldn’t sterilize the planets. Life might be common for red dwarf worlds after all.

Reference: Abrevaya, X C, et al. “An experimental study of the biological impact of a superflare on the TRAPPIST-1 planets.” Monthly Notices of the Royal Astronomical Society (2024): stae2433.

The post Could Life at TRAPPIST-1 Survive the Star's Superflares? appeared first on Universe Today.

SpaceX launched another batch of its Starlink internet satellites from Florida's Space Coast on Saturday evening (Oct. 26).

Lakes appearing in the Sahara desert captured in satellite images after a cyclone dumped a years' worth of rain on northern Africa in just a few days.

On Episode 134 of This Week In Space, Rod and Tariq talk with Ben Dickow about a magnificent, full-sized shuttle mockup, its history and future plans.

Boeing's Starliner had propulsion issues after launching on its first test mission with astronauts. Six weeks after the mission concluded, NASA is working on what to do next.

A Rolex watch that was flown to the moon is now the most expensive astronaut timepiece to sell at auction. The personal GMT-Master chronometer worn by Edgar Mitchell sold for $2.2 million.

Convicted of a crime that never happened, Roberson’s case is a prime example of how the U.S. legal system often fails to recognize advances in scientific knowledge

Is our universe haunted?

Join me on an unforgettable trip filled with breathtaking auroras and exciting daytime adventures with The Northern Lights Company.

While such organisms may or may not exist in the universe, the research has important implications for future human endeavors in space.

Exoplanets are a fascinating aspect of the study of the Universe. TRAPPIST-1 is perhaps one of the most intriguing exoplanet systems discovered to date with no less than 7 Earth-sized worlds. They orbit a red dwarf star which can unfortunately be a little feisty, hurling catastrophic flares out into space. These flares could easily strip atmospheres away from the alien worlds rendering them uninhabitable. A new piece of research suggests this may not be true and that the rocky planets may be able to maintain a stable atmosphere after all. 

Exoplanets are alien worlds outside of our solar system orbiting other stars. Their discovery in the 1990’s was just the beginning and to date over 5,000 have been identified. They vary massively in composition from small, rocky Earth-sized planets to gas giants like Jupiter. A few of them orbit in the host star’s habitable zone raising the tantalising possibility that life may exist out there in the universe. 

All manner of techniques and telescopes have been used to hunt for exoplanets and to explore their nature. More recently the James Webb Space Telescope (JWST) which was launched in late 2021 has been engaged to that end. The design of the JWST is such that it is capable of observing nearby exoplanets in greater detail than before. 

Artist impression of the James Webb Space Telescope

TRAPPIST-1 is 40 light years away in the constellation Aquarius. It is one of the most fascinating exoplanetary systems discovered to date with 7 Earth-sized planets in orbit around a cool dwarf star. Like all stars, TRAPPIST-1 has a habitable zone, a region around the star within which, the conditions are likely to be conducive to life for any planet that happens to be orbiting at that distance. TRAPPIST-1 has 3 of the 7 planets orbiting in this zone offering a tantalising possibility of extra-terrestrial life. 

The planets of TRAPPIST-1 are classic rocky objects in orbit around an M-dwarf star. These stars are the most common in the universe but previous studies suggest the intense UV radiation from TRAPPIST-1 would fry any atmosphere or surface water. It has been thought that the hydrogen molecules would escape, leaving behind significant quantities of reactive oxygen which would likely inhibit the development of organic chemistry. 

Illustration of the tidally locked world TRAPPIST-1f. Credit: NASA/JPL-Caltech

A recent study led by the University of Washington has been published in the journal Nature Communications which suggests an alternative theory. The team led by Joshua Krissansen-Totton suggest that instead, a stable atmosphere can be created and sustained following an alternative sequence of events. 

During the evolution of the planet, and following its molten state, millions of years of cooling lead to the solid rocky planets we see today. They report that their data shows hydrogen and other light gasses escaped out into space for planets near to the star. For those that are further away where things are a little cooler, the hydrogen reacted with oxygen and iron deep inside the planet producing water and other heavier gasses. These processes may have created a stable atmosphere after all. 

Observations from the JWST can detect higher levels of thermal infrared energy from the inner planets and they reveal the absence of a thick atmosphere. The team suggest more distant planets may have a more stable environment that might even produce a habitable environment. JWST has to date, been unable to detect atmospheres but with new ground based telescopes coming online and with new imaging techniques, the TRAPPIST-1  planets in the habitable zone may soon reveal their mysteries. 

Source : Rocky planets orbiting small stars could have stable atmospheres needed to support life

The post Red Dwarf Stars Might Be Able to Hold Onto Their Atmospheres After All appeared first on Universe Today.

IDW Publishing just delivered a zany new 'choose your own 'Star Trek: Lower Decks' adventure book, the series' first "interactive graphic novel."