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Single-celled organisms called archaea can become multicellular when compressed, highlighting the role of physical forces in evolution

A new United Nations expert study of the effects of nuclear war would spur informed and inclusive global debate on what nuclear war means for people and the planet today

This idea really is quite a fascinating one. Currently a trip to Mars would require large amounts of air, water and other resources to sustain human life but would also expose travellers to harmful levels of radiation. A wonderful solution has been proposed in a new paper recently published by researchers from Ukraine. They propose that asteroids which already travel relatively close by Earth, Mars and even Venus already could be used to hop between the planets. They are already making the journey anyway and so perhaps the cosmos already provides the solution to interplanetary travel. 

After a return to the Moon, the red planet Mars is next on the list for human exploration. On average it is 225 million km away so a round trip would require astronauts to be away from home for about 3 years! Spending this length of time in space raises a number of serious health risks many of which are caused by prolonged exposure to radiation and microgravity. Over time, muscles and bone density will decline so that the skeletal part of the body will no longer bear enough weight to sustain a return to Earth’s gravity. The cardiovascular system would adjust to microgravity too making heart issues likely upon return. There would be an increased risk of cancer and damage to the nervous system as a result of the prolonged exposure to radiation. The list goes on! 

Mars, Credit NASA

The paper recently authored by A. S. Kasianchuk and V.M. Reshetnyk from the National University of Kyiv in Ukraine they report upon their analysis of the orbit of more than 35,000 near-Earth asteroids. They have been looking for the possibility of successive approaches to all pairs of planets Earth – Venus and Earth – Mars within a time range of 2020 to 2120. If successive passes exist then why not, the team suggest, use the asteroids as interplanetary busses to provide a fast transfer between the planets, possibly even as fast as 180 days. 120 candidates were discovered for Earth-Mars, Earth-Venus, Mars-Earth, Venus-Earth, and even Mars-Venus and Venus-Mars!

Image of Venus taken by NASA’s Pioneer-Venus Orbiter in 1979. (Credit: NASA)

It is a tantalising prospect that instead of mounting a massive rocket based mission to get to Mars or even Venus, that the use of Near Earth Objects (NEO) might provide a natural solution. They would certainly provide a fast transfer between planets but would still require some form of technological solution to radiation protection. The quicker the journey, the lower the risk from radiation so careful selection is an important part of the process. 

The team have produced quite an extensive list of potentials NEO’s for transfers between the inner planets but as new NEO’s are discovered the list will grow. The work provides a snapshot in time of the possible candidates but it requires on going work to keep the list up to date as more asteroids are discovered and orbital elements are refined. NASA’s NEO Surveyor mission has been set the challenge to find more than 90% of all  NEO’s larger than 140 metres in diameter. This will certainly provide a useful resource to the study.

An artist’s conception of an NEO asteroid orbiting the Sun. Credit: NASA/JPL.

Among the asteroids identified, size and proximity to the target planet needs to be considered. Analysis of the overall mission needs to be carefully worked too. If a spacecraft stays in open space for a longer period of time than inside a NEW for example, the effectiveness of the approach must be carefully weighed up. 

It’s an interesting proposition though. With appropriate technological solutions, a carefully selected asteroid can serve not only as a fuel station but also, if shelter is taken beneath the surface for example in caves, could offer radiation protection too. There are significant challenges ahead before this all becomes a reality but with the ever increasing drive to reduce the cost and ecological impact of space flight it is one that most definitely needs further careful analysis. 

Source : The search for NEOs as potential candidates for use in space missions to Venus and Mars

The post Astronauts Could Take an Asteroid Ferry from Earth to Mars appeared first on Universe Today.

These therapies dampen fears absent direct exposure—no need to be in the room with a live tarantula

Ancient stone goods found across France may have been made by skilled craftspeople in what is now Paris, who traded along vast networks

Ancient stone goods found across France may have been made by skilled craftspeople in what is now Paris, who traded along vast networks

China has been operating its completed Tiangong space station for almost two years and is now looking to expand its capabilities with new modules and spacecraft.

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.