Astronomy
China rolls out rocket for next astronaut mission to Tiangong space station (photos)
Cocaine seems to hijack brain pathways that prioritise food and water
Cocaine seems to hijack brain pathways that prioritise food and water
FDA Recalls Heart Pumps Linked to Deaths and Injuries
Two medical devices that mechanically pump blood to the heart have caused hundreds of injuries and more than a dozen deaths
See Amazing Views of the April 8th Total Solar Eclipse from Space
Millions of viewers were wowed by last week’s total solar eclipse. Now, we get to see the eclipse from another angle: space.
The post See Amazing Views of the April 8th Total Solar Eclipse from Space appeared first on Sky & Telescope.
SpaceX launches Starlink satellites on company's 40th mission of 2024 (video)
The Mystery of Cosmic Rays Deepens
Cosmic rays are high-energy particles accelerated to extreme velocities approaching the speed of light. It takes an extremely powerful event to send these bits of matter blazing through the Universe. Astronomers theorize that cosmic rays are ejected by supernova explosions that mark the death of supergiant stars. But recent data collected by the Fermi Gamma-ray space telescope casts doubt on this production method for cosmic rays, and has astronomers digging for an explanation.
It’s not easy to tell where a cosmic ray comes from. Most cosmic rays are hydrogen nuclei, others are protons, or free-flying electrons. These are charged particles, meaning that every time they come across other matter in the Universe with a magnetic field, they change course, causing them to zig-zag through space.
The direction a cosmic ray comes from when it hits Earth, then, is not likely the direction it started in.
But there are ways to indirectly track down their origin. One of the more promising methods is by observing gamma rays (which do travel in straight lines, thankfully).
When cosmic rays bump into other bits of matter, they produce gamma rays. So when a supernova goes off and sends cosmic rays out into the Universe, it should also send a gamma-ray signal letting us know it’s happening.
That’s the theory, anyway.
But the evidence hasn’t matched expectations. Studies of old, distant supernovas show some gamma ray production occurring, but not as much as predicted. Astronomers explained away the missing radiation as a result of the supernovas’ age and distance. But in 2023, the Fermi telescope captured a bright new supernova occurring nearby. Named SN 2023ixf, the supernova went off just 22 million light-years away in a galaxy called Messier 101 (better known as the ‘Pinwheel Galaxy’). And yet again, gamma rays were conspicuously absent.
NASA Goddard.“Astrophysicists previously estimated that supernovae convert about 10% of their total energy into cosmic ray acceleration,” said Guillem Martí-Devesa, University of Trieste. “But we have never observed this process directly. With the new observations of SN 2023ixf, our calculations result in an energy conversion as low as 1% within a few days after the explosion. This doesn’t rule out supernovae as cosmic ray factories, but it does mean we have more to learn about their production.”
So where is all the missing gamma radiation?
It’s possible that interstellar material around the exploding star could have blocked gamma rays from reaching the Fermi telescope. But it might also mean that astronomers need to look for alternative explanations for the production of cosmic rays.
Nobody likes a good mystery better than astronomers, and digging into the missing gamma radiation could eventually tell us a whole lot more about cosmic rays and where they come from.
Astronomers plan to study SN 2023ixf in other wavelengths to improve their models of the event, and will of course keep an eye out for the next big supernova, in an effort to understand what is going on.
The most recent gamma-ray data from SN 2023ixf will be published in Astronomy and Astrophysics in a paper led by Martí-Devesa.
The post The Mystery of Cosmic Rays Deepens appeared first on Universe Today.
Deadly African Heat Wave Would Not Have Been Possible without Climate Change
Scientists say extreme temperatures that reached 119 degrees Fahrenheit and killed at least 100 people in parts of West Africa would only occur every 200 years in the absence of climate change
Water Touches Everything
The Theoretical Physicist Who Worked with J. Robert Oppenheimer at the Dawn of the Nuclear Age
Melba Phillips co-authored a paper with J. Robert Oppenheimer in 1935 that proved important in the development of nuclear physics. Later she became an outspoken critic of nuclear weapons
NASA Confirms that a Piece of its Battery Pack Smashed into a Florida Home
NASA is in the business of launching things into orbit. But what goes up must come down, and if whatever is coming down doesn’t burn up in the atmosphere, it will strike Earth somewhere.
Even Florida isn’t safe.
Careful consideration goes into releasing debris from the International Space Station. Its mass is measured and calculated so that it burns up during re-entry to Earth’s atmosphere. But in March 2024, something didn’t go as planned.
It all started in 2021 when astronauts replaced the ISS’s nickel hydride batteries with lithium-ion batteries. It was part of a power system upgrade, and the expired batteries added up to about 2,630 kg (5,800 lbs.) On March 8th, 2021, ground controllers used the ISS’s robotic arm to release a pallet full of the expired batteries into space, where orbital decay would eventually send them plummeting into Earth’s atmosphere.
The Canadarm 2 robotic arm releases a pallet of spent batteries into space on March 8th, 2021. Image Credit: NASAIt was the most massive debris release from the ISS. According to calculations, it should have burned up when it entered the atmosphere on March 8th, 2024. But it didn’t.
Alejandro Otero owns a home in Naples, Florida. He wasn’t home on March 8th when there was a loud crash as something smashed into his roof. But his son was. “It was a tremendous sound. It almost hit my son,” Otero told CNN affiliate WINK News in March. “He was two rooms over and heard it all.”
“Something ripped through the house and then made a big hole in the floor and on the ceiling,” Otero explained. “I’m super grateful that nobody got hurt.”
This time, nobody got hurt. But NASA is taking the accident seriously.
Otero cooperated with NASA, and NASA examined the object at the Kennedy Space Center in Florida. They determined the debris was from a stanchion used to mount the old batteries on a special cargo pallet.
This image shows an intact stanchion and the recovered stanchion from the NASA flight support equipment used to mount International Space Station batteries on a cargo pallet. The stanchion survived re-entry through Earth’s atmosphere on March 8, 2024, and impacted a home in Naples, Florida. Image Credit: NASAThe stanchion is made of the superalloy Inconel to understand extreme environments, including extreme heat. It weighs 725 grams (1.6 lbs.) It’s about 10 cm (4 inches) in height and 4 cm (1.6 inches) in diameter.
Even though it’s a tiny object, it’s the type of accident that NASA and the ISS are determined to avoid. “The International Space Station will perform a detailed investigation of the jettison and re-entry analysis to determine the cause of the debris survival and to update modelling and analysis, as needed,” a NASA statement read.
Investigators want to know how the debris survived without burning up on re-entry. Engineers use models to understand how objects react to re-entry heat and break apart, and this event will refine those models. In fact, every time an object reaches the ground, the models are updated.
For Otero, this accident amounted to little more than a great story and an insurance claim. But the chunk of stanchion could’ve seriously injured someone or even killed someone.
In January 1997, Lottie Williams was walking through a park with friends in Tulsa, Oklahoma, in the early morning. They saw a huge fireball in the sky and felt a rush of excitement, thinking they were seeing a shooting star. “We were stunned, in awe,” Williams told FoxNews.com. “It was beautiful.”
Then, something struck her lightly on the shoulder before falling to the ground. It was like a piece of metallic fabric, and after reaching out to some authorities, she learned that it was part of a fuel tank from a Delta II rocket. She’s the first person known to have been hit with space debris. Had it been something with more mass, who knows if Williams would’ve been injured or worse?
That’s why NASA takes debris survival so seriously. The guilt of injuring or even killing someone would be overwhelming. A serious debris accident could also make things very uncomfortable going forward, as people can be fickle and not prone to critical thinking. NASA’s already struggling with budget constraints; the organization doesn’t need any nasty public relations to imperil its progress further.
Complicating matters is that the ESA warned that not all the battery debris would burn up. There wasn’t much else they could do. Fluctuating atmospheric drag made it impossible to predict where debris would strike Earth.
Those who follow space know how complicated and unpredictable this is. And they likewise know how improbable an injury is. But there’s always a non-zero chance of injury or death from space debris for someone going about their life here on the Earth’s surface. If that ever happened, the scrutiny would be intense.
Is it statistical fear-mongering to consider space debris striking someone, injuring them, or worse? Probably. When we see a shooting star in the sky, it’s safe to enjoy the spectacle without worry.
But maybe, just in case, out of an abundance of caution, Don’t Look Up.
The post NASA Confirms that a Piece of its Battery Pack Smashed into a Florida Home appeared first on Universe Today.
Fossil snake discovered in India may have been the largest ever
Fossil snake discovered in India may have been the largest ever
Sorry, little green men: Alien life might actually be purple
Zack Snyder on sticking the landing for the 2nd half of Netflix's 'Rebel Moon' (exclusive)
Russia launches new Angara A5 heavy-lift rocket on 4th orbital test mission (photos)
This Nearly 50-Foot Snake Was One of the Largest to Slither the Earth
Fossilized vertebrae that were found in an Indian coal mine belonged to a gigantic and previously unknown snake species