Astronomy

Mice that exercised soon after waking up had stronger and longer bones than those that exercised later in the day  

India's Agnikul Cosmos successfully launched a test vehicle powered by a homegrown 3D printed rocket engine.

The Chang’e 6 mission is China’s second to touch down on the lunar far side and will retrieve samples for analysis on Earth

This year's U.S. Astronaut Hall of Fame induction ceremony was a reunion of sorts, as honorees David Hilmers and Marsha Ivins took the stage under Atlantis, the shuttle on which they crossed paths.

A small South Pacific fern boasts more than 50 times as many base pairs as the human genome

A rare sighting of a giant pangolin revives hopes for the species' survival in West Africa, despite threats from poaching and deforestation

A rare sighting of a giant pangolin revives hopes for the species' survival in West Africa, despite threats from poaching and deforestation

A Russian military satellite with a "history of unusual maneuvering" was spotted as it approached a satellite in geostationary orbit in April 2024.

"Twisted Tatooine" binary star systems could be a major player in ejecting rogue planets that go on to drift through the Milky Way without a stellar parent to heat or illuminate them.

As we discover more and more exoplanets – and the current total is in excess of 5,200 – we continue to try to learn more about them. Astrobiologists busy themselves analysing their atmospheres searching for anything that provides a sign of life. It is quite conceivable of course that the Universe is teeming with life based on very different chemistry to ours but we often look to life on Earth to know what to look for. On Earth for example, ozone forms through photolysis of molecular oxygen and is an indicator of life. Using the James Webb Space Telescope astronomers are searching stars in the habitable zone of their star for the presence of ozone and how it impacts their climate.

It’s tantalising that 425 of the exoplanets detected so far, exist in their stars habitable zone. It is in this region where the climate on the planet may well be suitable to sustain life. A significant subset of those planets are Earth-like in nature and will therefore have a fairly temperate climate. In addition, they all seem to orbit M-dwarf type stars which means they are likely to be impacted by tidal spin-synchronisation (due to the effects of the tides, one face of the planet may well be kept facing the star). One impact of this is the potential for large contrast in daytime and night-time irradiation which can drive strong convection on the day side of the planet.  

The strong convection can drive winds around the equatorial region that are persistently higher faster than the rotation of the planet. It can also create Rosby Waves which naturally occur in the Earth’s ocean and atmosphere – in any rotating fluids or gas. Together these can control the distribution of chemicals in the atmosphere, in particular ozone. 

In Earth’s atmosphere the presence of molecular oxygen is an indicator of life since it is produced largely from photosynthesis in plants. The molecular oxygen collides with nitrogen in the atmosphere to produce ozone so the presence of the latter is an indicator of biological processes. There is a chance though that the molecular oxygen in exoplanet atmospheres are the result of different ratios of near and far UV that can drive a non-biological build up. 

In a new piece of research reported in a paper by lead author Paolo De Luca and team, they report their findings having leveraged climate model simulations on Proxima Centauri b. The Earth-sized exoplanet orbits the red dwarf star Proxima Centauri, the closest star to our own at a distance of 4,.2 light years. 

An artist’s conception of a violent flare erupting from the red dwarf star Proxima Centauri. Such flares can obliterate atmospheres of nearby planets. Credit: NRAO/S. Dagnello.

They report that the analysis of atmospheres of tidally locked Earth-like exoplanets received a massive boost as a result of the development of the James Webb Telescope. The team reveal that their climate modelling (including the use of interactive ozone) globally increases temperature in the stratosphere. This in turn induces regional variations of surface temperature and also reduces the temperature contrast between day and night side. 

Whilst the team have not been able to identify life on exoplanets, that was not their intention. What they have achieved is the ability to understand the exoplanet atmospheres using the James Webb Space Telescope, some of the processes that lead to atmospheric ozone and the impacts on temperatures. 

Source : The impact of Ozone on Earth-like exoplanet climate dynamics: the case of Proxima Centauri b

The post What Impact Does Ozone Have on an Exoplanet? appeared first on Universe Today.

Strange solids called temporal metamaterials finally make it possible to investigate the controversial idea of quantum friction – and push special relativity to its limits

Strange solids called temporal metamaterials finally make it possible to investigate the controversial idea of quantum friction – and push special relativity to its limits

China Chang’e 6 mission has landed on the Moon and is now set to perform another first: a sample return from the lunar farside.

The post Whirlwind Chang’e 6 Mission Collects Lunar Samples, Heads Back Home appeared first on Sky & Telescope.

A rare fossil skull provides strong evidence that the Dromornithidae, an extinct group of Australian flightless birds, were related to geese and ducks

A rare fossil skull provides strong evidence that the Dromornithidae, an extinct group of Australian flightless birds, were related to geese and ducks

Anthony Fauci, who led the National Institute of Allergy and Infectious Diseases early in the COVID pandemic, is facing a congressional committee about questionable e-mails from agency officials

China's Chang'e-6 lunar mission has carried out a successful far side touchdown and is already busily gathering specimens for send-off to Earth.

Three U.S. dairy workers have been infected with H5N1 after contact with sick cows, and all of them developed eye symptoms

Scientists reveal the face of Australia’s massive, extinct “giga-goose”

China's experimental space plane released an unknown object into Earth’s orbit on May 24, which could be a subsatellite deployment or an indication the spacecraft is nearing the end of its third mission.