OrbitalHub

NASA Jet Propulsion Laboratory dicit:

NASA’s InSight lander detected seismic waves from a meteoroid and was able to capture the sound of the space rock striking the surface of Mars for the first time. The meteoroid – the term used for incoming space rocks before they hit the ground – entered Mars’ atmosphere on Sept. 5, 2021, exploding into at least three shards that each left craters behind. Mars’ atmosphere is just 1% as dense as Earth’s, allowing far more meteoroids to pass through and impact the Red Planet’s surface.

This event marks the first time seismic and acoustic waves from an impact were detected on the Red Planet. Why does this meteoroid impact sound like a “bloop” in the video? It has to do with a peculiar atmospheric effect that’s also observed in deserts on Earth.

After sunset, the atmosphere retains some heat accumulated during the day. Sound waves travel through this heated atmosphere at different speeds, depending on their frequency. As a result, lower-pitched sounds arrive before high-pitched sounds. An observer close to the impact would hear a “bang,” while someone many miles away would hear the bass sounds first, creating a “bloop.”

NASA’s Mars Reconnaissance Orbiter flew over the estimated impact site to confirm the location. The orbiter used its black-and-white Context Camera to reveal three darkened spots on the surface.

After locating these spots, the orbiter’s team used the High-Resolution Imaging Science Experiment camera, or HiRISE, to get a color close-up of the craters. Because HiRISE sees wavelengths the human eye can’t detect, scientists change the camera’s filters to enhance the color of the image. The areas that appear blue around the craters are where dust has been removed or disturbed by the blast of the impact. Martian dust is bright and red, so removing it makes the surface appear relatively dark and blue.

Credit: NASA/JPL-Caltech/University of Maryland/University of Arizona/CNES/IPGP/Manchu/Bureau 21/ETH Zurich/Kirschner/van Driel

Lockheed Martin dicit:

You can’t get all the way to Mars without fuel – and a lot of it. Chemical propulsion has been the standard for spaceflight for decades, but if humans are to travel to Mars, they need a propulsion technology much more powerful.

Although they’re relatively new – nuclear systems for propulsion or electrical power are simple. Fission-based systems work by splitting low-enriched uranium atoms in a reactor to create heat. Super-cooled hydrogen is flowed into the reactor and the heat from the uranium quickly turns the hydrogen into a very hot, pressurized gas.

In nuclear thermal propulsion (NTP), the super-hot pressurized hydrogen is funnelled out a nozzle to create a powerful thrust. The mechanics of an NTP engine are much simpler and vastly more efficient than chemical propellant engines.

In fission surface power systems, the heat from the splitting of uranium atoms is converted to electricity. These systems can produce at least 40 kilowatts of power and can operate on permanently shadowed regions of the Moon.

Credit: Lockheed Martin

NASA dicit:

NASA’s Perseverance Mars rover used its Mastcam-Z camera system to shoot video of Phobos, one of Mars’ two moons, eclipsing the Sun. It’s the most zoomed-in, highest frame-rate observation of a Phobos solar eclipse ever taken from the Martian surface.

Several Mars rovers have observed Phobos crossing in front of the Sun over the past 18 years. Spirit and Opportunity made the first observations back in 2004; Curiosity in 2019 was the first to record video of the event. Each time these eclipses are observed, they allow scientists to measure subtle shifts in Phobos’ orbit over time. The moon’s tidal forces pull on the deep interior of the Red Planet, as well as its crust and mantle; studying how much Phobos shifts over time reveals something about how resistant the crust and mantle are, and thus what kinds of materials they’re made of.

Video credit: NASA

NASA dicit:

Seasons change even on Mars and NASA’s fleet of explorers are helping scientists learn more about the effects on the Red Planet. NASA’s Perseverance and Curiosity rovers provide daily weather reports by measuring conditions such as humidity, temperature, and wind speed on the surface. Orbiters including Odyssey, Mars Atmosphere and Volatile EvolutioN (MAVEN), and the Mars Reconnaissance Orbiter (MRO) survey the scope and scale of storms from above. Changing weather conditions can be challenging for the spacecraft. The Ingenuity Mars Helicopter recently increased its rotor speed from 2,537 rpm to 2,700 rpm to fly in a thinner summer atmosphere. Meanwhile, NASA’s InSight lander, which is studying Mars’ interior, recently measured one of the biggest, longest-lasting marsquakes the mission has ever detected.

Video credit: NASA/JPL-Caltech/University of Arizona/ASU/MSSS

NASA dicit:

Guided tour of Mars’ Jezero Crater from NASA’s Perseverance rover provides a glimpse of the Martian landscape from the rover’s highest vantage point yet in the “Séítah” region.

Perseverance Project Scientist Ken Farley points out highlights in this Martian panorama from the rover’s Mastcam-Z instrument, including mountains that make up the crater rim, remnants of an ancient river delta that could preserve signs of ancient life, volcanic rocks, and boulders likely carried into the crater by the river in the distant past. The enhanced-color panorama was created from images taken on November 28, 2021.

The color enhancement exaggerates small changes in color from place to place in the scene. This makes it easier for the science team to use their everyday experience to interpret the landscape. The sky on Mars would not actually look blue to a human explorer on the Red Planet, but pinkish.

Video credit: NASA Jet Propulsion Laboratory

NASA dicit:

NASA’s Curiosity rover explores Mount Sharp, a 5-mile-tall (8-kilometer-tall) mountain within the basin of Gale Crater on Mars.

Curiosity landed nine years ago on August 5, 2012, with a mission to study whether different Martian environments could have supported microbial life in the ancient past, when long-lived lakes and groundwater existed within Gale Crater.

Video credit: NASA/JPL-Caltech/MSSS