Space and astronomy news
About 50,000 years ago, a nickel-iron meteorite some 50 meters across plowed into the Pleistocene-era grasslands of what is now Northern Arizona. It was traveling fast—about 13 kilometers per second. In just a few seconds, an impact dug out a crater just over a kilometer wide and spread rocks from the site for miles around.
Continue reading “Recreating the Extreme Forces of an Asteroid Impact in the Lab”
An astronaut’s gotta eat, right? Especially if they are on a long-duration mission to places like the Moon. Scientists have been looking into how the lunar regolith could possibly support growing food for humans, as growing plants for food and oxygen will be critical for future long-term lunar missions.
One company has been diligently researching this concept and they say there’s good news.
Continue reading “It Should be Possible to Farm on the Moon”
The early Universe was swimming with dwarf galaxies only a few hundred million years after the Big Bang. They merged with each other over time, building larger and more massive galaxies. At the same time, the giant black holes inside these dwarfs merged, too.
Continue reading “Supermassive Black Holes on a Collision Course”
On Mars, NASA’s Perseverance rover is busy collecting rock samples that will be retrieved and brought back to Earth by the Mars Sample Return (MSR) mission. This will be the first sample-return mission from Mars, allowing scientists to analyze Martian rocks directly using instruments and equipment too large and cumbersome to send to Mars. To this end, scientists want to ensure that Perseverance collects samples that satisfy two major science goals – searching for signs of life (“biosignatures”) and geologic dating.
To ensure they select the right samples, scientists must understand how rock samples formed and how they might have been altered over time. According to a new NASA study, Martian rocks may have been “shocked” by meteorite impacts during its early history (the Late Heavy Bombardment period). The role these shocks played in shaping Martian rocks could provide fresh insights into the planet’s geological history, which could prove invaluable in the search for evidence of past life on Mars.
Continue reading “How are Mars Rocks Getting “Shocked” by Meteorite Impacts?”
In the first data taken last summer with the Near Infrared Camera (NIRCam) on the new James Webb Space Telescope, astronomers found six galaxies from a time when the Universe was only 3% of its current age, just 500-700 million years after the Big Bang. While its incredible JWST saw these galaxies from so long ago, the data also pose a mystery.
These galaxies should be mere infants, but instead they resemble galaxies of today, containing 100 times more stellar mass than astronomers were expecting to see so soon after the beginning of the Universe. If confirmed, this finding calls into question the current thinking of galaxy formation and challenges most models of cosmology.
Continue reading ““The Universe Breakers”: Six Galaxies That are Too Big, Too Early”
The Milky Way Galaxy contains an estimated one hundred billion stars. Between these lies the Interstellar Medium (ISM), a region permeated by gas and dust grains. This dust is largely composed of heavier elements, including silicate minerals, ice, carbon, and iron compounds. This dust plays a key role in the evolution of galaxies, facilitating the gravitational collapse of gas clouds to form new stars. This galactic dust is measurable by how it attenuates starlight from distant galaxies, causing it to shift from ultraviolet to far-infrared radiation.
However, the origin of various dust grains is still a mystery, especially during the early Universe when heavier elements are thought to have been scarce. Previously, scientists believed that elements like carbon took hundreds of millions of years to form and could not have existed before about 2.5 billion years after the Big Bang. Using data obtained by the JWST Advanced Deep Extragalactic Survey (JADES), an international team of astronomers and astrophysicists report the detection of carbonaceous grains around a galaxy that existed roughly 1 billion years after the Big Bang.
Continue reading “Clouds of Carbon Dust Seen When the Universe was Less Than a Billion Years Old”
Dust storms are a serious hazard on Mars. While smaller storms and dust devils happen regularly, larger ones happen every year (during summer in the southern hemisphere) and can cover continent-sized areas for weeks. Once every three Martian years (about five and a half Earth years), the storms can become large enough to encompass the entire planet and last up to two months. These storms play a major role in the dynamic processes that shape the surface of Mars and are sometimes visible from Earth (like the 2018 storm that ended the Opportunity rover’s mission).
When Martian storms become particularly strong, the friction between dust grains causes them to become electrified, transferring positive and negative charges through static electricity. According to research led by planetary scientist Alian Wang at Washington University in St. Louis, this electrical force could be the major driving force of the Martian chlorine cycle. Based on their analysis, Wang and her colleagues believe this process could account for the abundant perchlorates and other chemicals that robotic missions have detected in Martian soil.
Continue reading “Dust Storms on Mars Generate Static Electricity. What Does This Do to Its Surface?”
Sending a lander to Venus presents several huge engineering problems. Granted, we’d get a break from the nail-biting entry, descent and landing, since Venus’ atmosphere is so thick, a lander would settle gently to the surface like a stone settles in water — no sky cranes or retrorockets required.
But the rest of the endeavor is fraught with challenges. The average temperature at the surface is 455 degrees C (850 F), hot enough to melt lead. The mix of chemicals that make up the atmosphere, such as sulfuric acid, is corrosive to most metals. And the crushing atmospheric pressure is roughly equivalent to being 1,500 meters (5,000 ft) under water. These extreme environmental conditions are where metals and electronics go to die; therefore, the few Venus lander missions that have made it to the surface — like the Soviet Venera missions — only lasted two hours or less. Any future landers or rovers will need to have nearly super-hero-type characteristics to endure on the surface of Earth’s evil twin.
But there’s one additional challenge that might be close to being solved: creating batteries that can operate long enough in Venus’ hellish conditions to make a lander mission worth the effort.
Continue reading “Can a Venus Lander Survive Longer Than a Few Minutes?”
If you’ve ever been at sea or visited a seacoast, you probably looked out at the vast expanse of ocean and wondered, “How did all this water get here?” The answer goes back to Earth’s origins some 4.5 billion years ago. In those early times, water-rich planetesimals and other bodies transported water to our still-growing planet. A recent discovery of a previously unknown population of such asteroids between Mars and Jupiter seems to prove that point.
Continue reading “Astronomers Find a Group of Water-rich Asteroids”
The two brightest planets pass less than half a degree apart at dusk during a spectacular conjunction on the night of March 1st.
It has begun. Once every 12 to 18 months or so, I start fielding “what are those two bright objects in the sky?” questions. They’re none other than the third and fourth brightest natural objects in the sky (behind the Sun and the Moon), the planets Jupiter and Venus. If skies are clear, you can see them get ever closer together from one night to the next, as they meet up during a spectacular conjunction on the night of March 1st/2nd.
Continue reading “Cosmic Conjunction: Jupiter Meets Venus on March 1st”