Latest news with #LaboratoryforAtmosphericandSpacePhysics
Yahoo
3 days ago
- General
- Yahoo
NASA spots sputtering for first time, cracks Mars' lost atmosphere mystery
Mars just gave up one of its oldest secrets — and it took a decade, a spacecraft, and a cosmic cannonball to catch it in the act. For the first time, NASA's MAVEN mission has directly observed a process called sputtering, an elusive atmospheric escape mechanism where energetic charged particles from the solar wind slam into the Martian atmosphere, knocking atoms into space. This violent interaction may be a key reason why Mars lost its thick atmosphere and, with it, the ability to sustain liquid water on its surface. The breakthrough marks a major milestone for MAVEN, a mission under NASA's Mars Exploration Program dedicated to uncovering how the Red Planet lost its atmosphere. While scientists had long suspected the process played a role in the Red Planet's atmospheric erosion, they lacked concrete evidence. 'It's like doing a cannonball in a pool,' said Shannon Curry, principal investigator of MAVEN at the Laboratory for Atmospheric and Space Physics at the University of Colorado Boulder and lead author of the study in a release. 'The cannonball, in this case, is the heavy ions crashing into the atmosphere really fast and splashing neutral atoms and molecules out.' Previous findings—like the imbalance between lighter and heavier argon isotopes in Mars' atmosphere—offered only indirect clues, pointing to sputtering's fingerprints without capturing the act itself. Since lighter isotopes naturally reside higher in the atmosphere, their scarcity compared to heavier ones strongly suggested they had been knocked away into space. And the only known process capable of selectively removing these lighter isotopes is sputtering. 'It is like we found the ashes from a campfire,' said Curry. 'But we wanted to see the actual fire, in this case sputtering, directly.' Now, using data from three instruments aboard MAVEN—the Solar Wind Ion Analyzer, the Magnetometer, and the Neutral Gas and Ion Mass Spectrometer—researchers have, for the first time, captured sputtering in action. Additionally, the team needed measurements across the dayside and the nightside of the planet at low altitudes, which takes years to observe. By combining data from three of MAVEN's instruments, scientists created the first detailed map linking sputtered argon to incoming solar wind. The map showed argon atoms high in the Martian atmosphere, precisely where energetic particles had slammed into it—clear, real-time evidence of sputtering in action. Even more striking, the process was occurring at a rate four times higher than expected, with activity intensifying during solar storms. This direct observation confirms that sputtering was a major driver of atmospheric loss during Mars' early years, when the young Sun was far more active. 'These results establish sputtering's role in the loss of Mars' atmosphere and in determining the history of water on Mars,' said Curry. The discovery helps fill a major gap in our understanding of Mars' transformation from a once-habitable planet to the cold, dry world we see today. It also provides critical insight into how planets evolve and what it might take for them to remain habitable. The findings have been published this week in Science Advances.
Yahoo
08-05-2025
- Science
- Yahoo
An out-of-control Russian spacecraft is about to slam into Earth – and it could be worse than it sounds
A Russian spacecraft is about to slam into Earth – and it could pose even more danger than it appears, experts have warned. The spacecraft, called Kosmos 482, is due to fall into Earth's atmosphere over the weekend. Experts have been tracking it closely to understand where and when exactly it will fall to Earth, in part to protect the people who could be below. That could be especially important because the spacecraft was specifically built to withstand intense conditions. That means that – unlike other recent and highly publicised space junk that has fallen to Earth – it could make it through the atmosphere intact and so pose yet more of a risk to anyone below. Kosmos 482 was built to land on Venus. It was launched from Earth in 1972 but one of its rockets malfunctioned. In the years since, it has been floating around Earth in an "eccentric" orbit that is set to collide with our planet over the weekend. Venus has temperatures of 477 degrees Celsius and a pressure more than 90 times our planet, and so the spacecraft was specifically built to withstand intense heat and pressure. As such, the roughly one meter and 500 kilogram spacecraft is likely to fall to Earth without burning up or breaking apart. Scientists expect it to arrive on Saturday morning, somewhere in the western hemisphere. But the exact time and location is very difficult to predict, and so it could arrive before or after that. Predicting the path of the spacecraft is difficult not only because of Kosmos 482's complex orbit but because it will be falling through the upper atmosphere, which can change dramatically and unpredictably because of the influence of the Sun as well as from Earth. 'The odds that this relic will land in a populated area are very low, it will very likely land in the ocean. But we can't yet say for certain where that will be," said Marcin Pilinski, a research scientist at the Laboratory for Atmospheric and Space Physics (LASP) at the University of Colorado Boulder. 'People who monitor asteroids to see if they will potentially impact Earth actually have an easier job. Those objects would enter at a really steep angle. They're not skimming part of the atmosphere for days or weeks like this spacecraft.' Error while retrieving data Sign in to access your portfolio Error while retrieving data Error while retrieving data Error while retrieving data Error while retrieving data
Yahoo
12-02-2025
- Science
- Yahoo
Huge solar storm in May 2024 spawned 2 new radiation belts around Earth
When you buy through links on our articles, Future and its syndication partners may earn a commission. The great solar storm of May 2024, which sparked beautiful auroral displays over much of the world, also created two new radiation belts that were observed with a satellite that came back from the dead. "This is really stunning," Xinlin Li, a professor at the Laboratory for Atmospheric and Space Physics at the University of Colorado, Boulder, said in a statement. "When we compared the data from before and after the storm, I said, 'Wow, this is something really new'." May 2024 saw a series of powerful storms erupt from our sun, spewing clouds of charged particles into space and culminating in a dramatic display of aurora borealis (northern lights) and aurora australis (southern lights) — the result of the most powerful geomagnetic storm experienced on Earth since March 1989. And NASA's Colorado Inner Radiation Belt Experiment (CIRBE) satellite had slept through the whole thing. Designed to study Earth's Van Allen radiation belts, CIRBE launched in April 2023 but fell silent in mid-April 2024 as the result of an onboard technical issue. It reawakened in June, and when it did come around, something had changed: Two brand-new radiation belts had appeared! The Van Allen radiation belts contain charged particles held in place by our Earth's magnetic field. There are two permanent belts, but the appearance of a new temporary radiation belt between the two permanent belts following a solar storm is not unusual — such short-lived belts were first detected in 2013. What CIRBE found to be unusual about these two new belts following the May 2024 event was their composition and lifetime. Usually, temporary belts that form following a solar storm are composed of high-energy electrons. One of the new belts found by CIRBE fit this pattern. However the other belt contained a substantial abundance of high-energy protons, too (protons are found also in the permanent radiation belts). Their presence in the new belt is believed to be the product of the intensity of May 2024's solar storms. Temporary radiation belts also usually last for at most four weeks before dissipating, but the new belts found by CIRBE had much longer lifespans: The electron-dominated belt survived for three months after the solar storm, while the proton-dominated belt is believed to still be wrapped around Earth even now. "These are really high-energy electrons and protons that have found their way into Earth's inner magnetic environment," said David Sibeck of NASA's Goddard Space Flight Center in Maryland. "Some might stay in this place for a very long time." While solar storms can create new radiation belts like this, solar storms can also destroy them. A modestly powerful storm in June 2024 reduced the electron-dominated belt, and another storm in August 2024 almost wiped it out completely. The proton-rich belt remains because it is located in a more stable region where its protons are less vulnerable to being bumped out of orbit. The existence of these temporary belts containing high-energy charged particles — the energy range of the electrons was 1.3 to 5 megaelectronvolts (MeV), and for the protons it was even greater at 6.8 to 20 MeV — could have repercussions for launching spacecraft through the Van Allen belts to reach geostationary orbit (which lies at an altitude of 22,236 miles, or 35,785 kilometers) or beyond. The charged particles contained within the belts can damage electrical components in satellites and spacecraft, while providing an extra radiation hazard for astronauts should they ever head back to the moon or venture on to Mars. To ensure the greatest safety at launch, some future missions, particularly those carrying a crew, may need to modify their launch plans or carry extra shielding following solar storms. However, previous measurements have revealed discrepancies between solar age observations and theoretical models — and now, a team led by Bétrisey has shown that it's probably the sun's own magnetic activity that is at fault. This is surprising, because the consensus had previously been that magnetic activity should have no impact at all. Bétrisey's team looked at 26.5 years' worth of data from two sun-observing programs. One was BISON, the Birmingham Solar Oscillations Network, which is a collection of ground-based solar observatories overseen by scientists at the University of Birmingham in the U.K. The other was GOLF, the Global Oscillations at Low Frequency instrument on the joint NASA–ESA SOHO (Solar and Heliospheric Observatory) mission that was launched in 1995. Our sun undergoes an 11-year cycle of magnetic activity, rising from solar minimum when there are hardly any sunspots visible, to solar maximum when there are sunspots, prominences, coronal mass ejections and flares aplenty. The BISON and GOLF data both showed a 6.5% difference when measuring the sun's age via helioseismology at solar minimum compared to at solar maximum. Furthermore, of the two solar cycles encompassed by the 26.5 years' worth of observations, both BISON and GOLF indicated that the cycle with stronger magnetic activity had a greater impact upon the discrepancy in the age measurement. Because, in the grand scheme of things, the sun is not a very active star, the results from BISON and GOLF suggest that "the impact of magnetic activity could be very significant for more active stars such as those that PLATO will detect," said Bétrisey. Related Stories: — May solar superstorm caused largest 'mass migration' of satellites in history — Solar storm frenzy of May 2024 was strong enough to affect the deep sea — Astrophotographer gets close-up look at monster sunspot that led to May's global auroras As for CIRBE, fate was nothing but ironic. While the effects of the May 2024 solar storm gave the cubesat one last shot at glory, it also spelled its doom. The storm injected a substantial amount of energy into Earth's upper atmosphere, inflating the thermosphere and increasing the atmospheric drag on the satellite. This slowed its orbit, causing it to drop down to increasingly lower altitudes. Eventually, it de-orbited and burned up in October. The discovery of the two new radiation belts was published on Feb. 6 in the Journal of Geophysical Research: Space Physics.
