Earlier this month, the Russian military conducted an anti-satellite (ASAT) missile test, launching a PL19 Nudol interceptor missile at a now-defunct Soviet-era intelligence satellite, KOSMOS 1408. The impact obliterated the spacecraft, creating a debris field consisting of approximately 1500 pieces of trackable debris, and potentially hundreds of thousands of pieces that are too small to monitor with ground-based radar. In the aftermath of the test, the debris field crossed the orbit of the International Space Station (ISS) repeatedly, causing the crew to take emergency precautions and shelter in their descent capsules, ready for a quick return to Earth in the event that the station was hit.
While the station and its crew escaped without harm this time around, the November 15 test demonstrated far too clearly that ASATs pose a real danger to human life. They can also wreak havoc on the rest of Earth’s space infrastructure, like communications satellites and other orbital systems. Debris from an ASAT test remains in orbit long after the initial incident is over (the higher the orbit, the longer lasting the debris), and if humanity’s space infrastructure is to be sustainable, the era of ASATs must come to an end, and soon.
Continue reading “It’s Time to Stop Doing Anti-Satellite Tests”
When Neil Armstrong, Buzz Aldrin, and Michael Collins returned from the Moon in the summer of 1969, they spent three weeks isolated in quarantine to make sure that they hadn’t brought back any microbial lifeforms from the Moon, which could prove harmful to Earth life. Later, once the Moon had been unequivocally proved to be a dead world, future Apollo missions were allowed to skip quarantine. Elsewhere in the solar system, however, NASA still has to take planetary biosecurity seriously, because life could be out there. If we bring it back to Earth, it could be a danger to us and our ecosystems. Conversely, microbial Earth life could invade a fragile alien ecosystem, destroying a newly discovered lifeform before we have the chance to study it. Imagine discovering life on Mars, only to realize that it was life we had brought there with us.
Continue reading “We’re Constantly Battling Invasive Species Here on Earth. What Does That Teach us About Infecting Other Worlds With Earth Life?”
A lack of effective radiation shielding is one of the biggest challenges still to be overcome if humans are to embark on long-term voyages into deep space. On Earth, the planet’s powerful magnetosphere protects us from the deadliest forms of radiation – those produced by solar flares, and galactic cosmic rays arriving from afar – that stream through the Solar System. Astronauts on the International Space Station, some 408km above the Earth, receive elevated levels of radiation, but are close enough to Earth that they still receive some shielding, and can stay on orbit for up to a year. The same can’t be said for astronauts traveling further out, to the Moon, for example, or, someday, to Mars. Future deep space voyagers will need to bring their own shielding with them – or, as a new paper suggests – grow it along the way.
Continue reading “Fungi Were Able to Absorb Radiation on the ISS. Could Astronauts Grow Their own Radiation Shields in Space?”
It’s been a long time coming, but NASA’s next moon rocket is just months from liftoff on its first uncrewed test flight. The Space Launch System (SLS) is a super heavy-lift vehicle capable of delivering 95 tons to Low Earth Orbit, but its primary purpose will be to deliver humans to lunar orbit and, eventually, to the lunar surface. SLS has been in development since 2011, and it’s faced a series of delays, but launch day is finally within sight. Earlier this month, the rocket was fully stacked for the first time in the Vehicle Assembly Building at the Kennedy Space Center, and the Orion capsule (the spacecraft’s crew cabin) was attached to the top. The full stack stands an impressive 322 feet tall, just shy of the Saturn V’s 363 feet.
Continue reading “Artemis 1 is Launching in February”
Giant planets like Saturn don’t just tilt over all by themselves: something has to knock them over, or tug on them gravitationally, to push them off axis. Scientists expect that when new planets are born, they form with almost no tilt at all, lining up like spinning tops, with their equators level to the orbital plane in which they circle around their sun.
But no planet in our solar system is perfectly level. Jupiter is the closest, boasting an obliquity (tilt) of just 3.12 degrees. Earth’s obliquity is much more substantive at 23.45 degrees, causing us to experience an annual cycle of seasons as our homeworld wobbles on its axis. Saturn’s tilt is more extreme yet, with an obliquity of 26.73 degrees (though it’s nowhere near as extreme as Uranus, which is practically sideways, spinning at a 97.86-degree angle to its orbital plane).
We can learn a lot from these obliquities.
Continue reading “Did Titan Give Saturn its Tilt?”
Nearly eight months into the Perseverance rover’s mission on Mars, researchers have confirmed that Jezero crater is (as was believed) an ancient lakebed, but more significantly, that it once experienced powerful flash floods that pushed boulders from tens of miles upstream into the crater basin.
Continue reading “Perseverance Sees Evidence of Flash Floods in Jezero Crater”
Sometime around 2.4 billion years ago, a nascent planet Earth underwent one of the most dramatic changes in its history. Known as the Great Oxidation Event, this period saw Earth’s atmosphere suddenly bloom with (previously scarce) molecular oxygen. The rapid alteration of the atmosphere’s composition was nothing short of a cataclysm for some early lifeforms (at the time, mostly simple celled prokaryotes). Anaerobic species – those that dwell in oxygen-free environments – experienced a near extinction-level event. But the Great Oxidation was also an opportunity for other forms of life to thrive. Oxygen in the atmosphere tempered the planetary greenhouse effect, turning methane into the less potent carbon dioxide, and ushering in a series of ice ages known as the Huronian Glaciation. But oxygen is an energy-rich molecule, and it also bolstered diversity and activity on the planet, as a powerful new source of fuel for living organisms.
The cause of this dramatic event? The tiniest of creatures: little ocean-dwelling cyanobacteria (sometimes known as blue-green algae) that had developed a new super-power never before seen on planet Earth: photosynthesis. This unique ability – to gain energy from sunlight and release oxygen as a waste product – was a revolutionary step for so small a critter. It quite literally changed the world.
Continue reading “When Did Photosynthesis Begin?”
The Colorado Ultraviolet Transit Experiment (aptly nicknamed CUTE) is a new, NASA-funded mission that aims to study the atmospheres of massive, superheated exoplanets – known as hot Jupiters – around distant stars. The miniaturized satellite, built by the Laboratory for Atmospheric and Space Physics (LASP) at the University of Colorado Boulder, is set to launch this Monday, September 27th on an Atlas V rocket.
Continue reading “A Tiny, Inexpensive Satellite Will be Studying the Atmospheres of hot Jupiters”
Understanding the birth of a planet is a challenging puzzle. We know that planets form inside clouds of gas and dust that surround new stars, known as protoplanetary disks. But grasping exactly how that process works – connecting the dots between a dust cloud and a finished planet – is not easy. An international team of astronomers is attempting to unlock some of those secrets, and have recently completed the most extensive chemical composition mapping of several protoplanetary discs around five young stars. Their research allows them to begin to piece together the chemical makeup of future exoplanets, offering a glimpse into the formation of new alien worlds.
Continue reading “Astronomers See Carbon-Rich Nebulae Where Planets are Forming”
On September 5, 2021, a team of MIT researchers successfully tested a high-temperature superconducting magnet, breaking the world record for the most powerful magnetic field strength ever produced. Reaching 20 Teslas (a measure of field intensity), this magnet could prove to be the key to unlocking nuclear fusion, and providing clean, carbon-free energy to the world.
Continue reading “Researchers Create the Most Powerful Magnet Ever Made on Earth: 20 Teslas”