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Marsquakes: NASA mission discovers that Mars is seismically active, among other surprises – CNN

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A NASA mission on Mars has recorded evidence of seismic activity, including 174 seismic events across Mars–and 20 events with a magnitude of three or four.
Marsquakes anyone?
Evidence of seismic activity on Mars that surprised the NASA team is part of a suite of six studies, published Monday in the journals Nature Geoscience and Nature Communications, capturing those first 10 months.
Since landing on Mars in November 2018, NASA’s InSight lander has been performing an extensive doctor’s checkup on the red planet, revealing some results that surprised InSight’s science team.
While the instruments onboard InSight were designed to capture two years worth of data, the seismometer, which measures Marsquakes, returned that intriguing data about Mars in much less time.
“We’re using geophysics to probe the deep interior of Mars. For the first time, we’ve established that Mars is a seismically active planet,” said Bruce Banerdt, InSight’s principal investigator. “That activity is greater than that of the moon, but less than on Earth.”
To be clear, a four magnitude Marsquake doesn’t feel the same as it would on Earth because the events on Mars occur deeper beneath the surface than they do on Earth.
If you were standing directly over the spot when a Marsquake happened, you might sense motion, but it wouldn’t cause any damage, said Suzanne Smrekar, InSight’s deputy principal investigator.
Still, confirming that Mars is seismically active was a major thrill for Insight’s team.
“We’ve been planning this mission for the last ten years, so it’s been a long road to get these results,” said Bruce Banerdt, InSight’s principal investigator.
NASA's InSight mission 'hears' first quake on Mars
Mars doesn’t have tectonic plates, unlike Earth, so its quakes occur through long-term cooling of the planet and other processes, scientists say. The brittle outer layers of the crust on Mars have to fracture to maintain themselves on the surface.
And Mars isn’t a perfect sphere, so the contractions of the crust cause stress and quakes to occur in some areas more than others, Smrekar said.
An analysis of the seismic waves detected by InSight revealed that the upper part of the Martian crust, the top six miles down from the surface, is “pretty broken up.” It’s another testament to the planet’s quake activity and fracturing.
“This is the first mission focused on taking direct geophysical measurements of any planet besides Earth, and it’s given us our first real understanding of Mars’ interior structure and geological processes,” said Nicholas Schmerr, an assistant professor of geology at the University of Maryland and a co-author of the seismicity study. “These data are helping us understand how the planet works, its rate of seismicity, how active it is and where it’s active.”
This is just the beginning of the data and secrets InSight can reveal about Mars, the scientists said.
Since the mission began, InSight has registered 450 Marsquakes in its catalog, coming from all across the planet and likely due to different causes, like landslides.
There has been an increase in small, low-frequency Marsquakes since early in the mission, Banerdt said. But they’ve yet to record any large Marsquakes, which is a goal of the mission.
There is no pattern to the quakes, but the increase in small quakes has them wondering if they are related to the Martian orbit or seasons, atmospheric changes or other unknown factors and phenomenon. For now, they remain odd and mysterious.
The InSight team members are still hopeful for big quakes in the future as well.
NASA's InSight mission is struggling to dig into MarsNASA's InSight mission is struggling to dig into Mars
Two other InSight investigations, including the heat probe taking Mars’ internal temperature and the Rotation and Interior Structure Experiment investigating Mars’ core will provide more data as the mission continues.

A fascinating landing site

Originally deemed a flat parking lot by NASA scientists, InSight’s landing site along the Martian equator is more interesting than previously believed based on ten months of studying it.
A dust devil passed over NASA's lander on MarsA dust devil passed over NASA's lander on Mars
InSight landed in an impact crater in Elysium Planitia. The surface is smooth and sandy with some rocks strewn about. The plains of Elysium Planitia, found along the Martian equator, are between highlands to the south and west and volcanoes to the north and east.
Surprisingly, the scientists discovered that it was the Cerberus Fossae fault lines that revealed the most recently geologically and volcanically active areas on Mars to date. The region is 994 miles to the east and also shows evidence of channels that once carried volcanic flow and liquid water.
The data meant volcanic flows occurred in the area within the last ten million years. Quakes are also registering from that area.
“If you take the thermal model of Mars, you wouldn’t expect such recent volcanism,” Smrekar said. “We wouldn’t expect it to be hot enough inside to be producing magma. This says there is some variability at depth on Mars and the source is not obvious at the surface. Something is allowing localized pockets of volcanism to occur.”

Surprising magnetic fields

Previous missions orbiting Mars have revealed that the planet no longer has a global magnetic field like Earth, yet scientists know it did in the ancient past.
The planet’s protective magnetic field mysteriously disappeared around 4.2 billion years ago as Mars cooled. The sun’s solar wind then stripped away the Martian atmosphere, leaving behind the thin one the planet has today.
NASA's InSight mission tunes in to the strange sounds of MarsNASA's InSight mission tunes in to the strange sounds of Mars
InSight’s magnetometer is the first instrument of its kind on the Martian surface and it unexpectedly detected that there are steady, localized magnetic fields 10 times stronger than predicted at the surface of the landing site.
These the fields are coming from magnetized volcanic rocks beneath Elysium Planitia, which formed when Mars had a global magnetic field. Those magnetic field particles became trapped in the rocks as they cooled, ensnaring the magnetization inside.
Because the subsurface of Mars didn’t heat up again to release that magnetization, the rocks remained the same ever since, said Catherine Johnson, the magnetometer co-investigator.
NASA's InSight mission catches Martian sunrise and sunsetNASA's InSight mission catches Martian sunrise and sunset
“The ground-level data give us a much more sensitive picture of magnetization over smaller areas, and where it’s coming from,” said Johnson. “In addition to showing that the magnetic field at the landing site was ten times stronger than the satellites anticipated, the data implied it was coming from nearby sources.”

A unique weather station

InSight also has a weather station simultaneously recording pressure, temperature and wind; it’s unlike any meterological suite ever used on Mars. Understanding how the atmosphere behaves at the Martian surface is key to understanding Mars and its ancient past.
Combined with the magnetometer, the scientists were able to detect 10,000 pressure vortexes moving through the landing site. They believe the vortexes could be the iconic Martian dust devils that spin up columns of dust along the surface, said Philippe Lognonne, principal investigator of the magnetometer.
Get a bird's-eye view of NASA's missions on MarsGet a bird's-eye view of NASA's missions on Mars

Trouble with the heat probe

Unfortunately, the heat probe that was deployed last year immediately ran into difficulty as it hit tough, clod-like dirt material 35 centimeters beneath the surface. The probe is supposed to hammer 9 to 16 feet beneath the surface to test how Mars internal temperature varies.
But the self-hammering probe only works if there’s friction in the soil, otherwise it bounces in place. The probe team will try another tactic, using the lander’s robotic arm to push down on the probe in hopes of continuing the investigation, Banerdt said.
Although they have more data than conclusions, the scientists likened their first 10 months to geophysicists trying to investigate Earth in the early 1900s, using the best tools they had to understand plate tectonics and earthquakes.
“This is an entire new world of processes for us, learning how to categorize these signals,” Banerdt said. “It’s still a very mysterious situation and we’re In the wild west of understanding what’s going on. We anticipate that within the next year, we can use this data to probe the deepest structures of Mars.”

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BEYOND LOCAL: NASA launches spacecraft to test asteroid defense concept – BayToday

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LOS ANGELES (AP) — NASA launched a spacecraft Tuesday night on a mission to smash into an asteroid and test whether it would be possible to knock a speeding space rock off course if one were to threaten Earth.

The DART spacecraft, short for Double Asteroid Redirection Test, lifted off from Vandenberg Space Force Base atop a SpaceX Falcon 9 rocket in a $330 million project with echoes of the Bruce Willis movie “Armageddon.”

If all goes well, the boxy, 1,200-pound (540-kilogram) craft will slam head-on into Dimorphos, an asteroid 525 feet (160 meters) across, at 15,000 mph (24,139 kph) next September.

“This isn’t going to destroy the asteroid. It’s just going to give it a small nudge,” said mission official Nancy Chabot of Johns Hopkins Applied Physics Laboratory, which is managing the project.

Dimorphos orbits a much larger asteroid called Didymos. The pair are no danger to Earth but offer scientists a better way to measure the effectiveness of a collision than a single asteroid flying through space.

Dimorphos completes one orbit of Didymos every 11 hours, 55 minutes. DART’s goal is a crash that will slow Dimorphos down and cause it to fall closer toward the bigger asteroid, shaving 10 minutes off its orbit.

The change in the orbital period will be measured by telescopes on Earth. The minimum change for the mission to be considered a success is 73 seconds.

The DART technique could prove useful for altering the course of an asteroid years or decades before it bears down on Earth with the potential for catastrophe.

A small nudge “would add up to a big change in its future position, and then the asteroid and the Earth wouldn’t be on a collision course,” Chabot said.

Scientists constantly search for asteroids and plot their courses to determine whether they could hit the planet.

“Although there isn’t a currently known asteroid that’s on an impact course with the Earth, we do know that there is a large population of near-Earth asteroids out there,” said Lindley Johnson, planetary defense officer at NASA. “The key to planetary defense is finding them well before they are an impact threat.”

DART will take 10 months to reach the asteroid pair. The collision will occur about 6.8 million miles (11 million kilometers) from Earth.

Ten days beforehand, DART will release a tiny observation spacecraft supplied by the Italian space agency that will follow it.

DART will stream video until it is destroyed on impact. Three minutes later, the trailing craft will make images of the impact site and material that is ejected.

John Antczak, The Associated Press

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Doing Photon Upconversion A Solid: Crystals That Convert Light To More Useful Wavelengths – Eurasia Review

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Solid-solution organic crystals have been brought into the quest for superior photon upconversion materials, which transform presently wasted long-wavelength light into more useful shorter wavelength light. Scientists from Tokyo Institute of Technology revisited a materials approach previously deemed lackluster—using a molecule originally developed for organic LEDs—achieving outstanding performance and efficiency. Their findings pave the way for many novel photonic technologies, such as better solar cells and photocatalysts for hydrogen and hydrocarbon productions.

Light is a powerful source of energy that can, if leveraged correctly, be used to drive stubborn chemical reactions, generate electricity, and run optoelectronic devices. However, in most applications, not all the wavelengths of light can be used. This is because the energy that each photon carries is inversely proportional to its wavelength, and chemical and physical processes are triggered by light only when the energy provided by individual photons exceeds a certain threshold.

This means that devices like solar cells cannot benefit from all the color contained in sunlight, as it comprises a mixture of photons with both high and low energies. Scientists worldwide are actively exploring materials to realize photon upconversion (PUC), by which photons with lower energies (longer wavelengths) are captured and re-emitted as photons with higher energies (shorter wavelengths). One promising way to realize this is through triplet-triplet annihilation (TTA). This process requires the combination of a sensitizer material and an annihilator material. The sensitizer absorbs low energy photons (long-wavelength light) and transfers its excited energy to the annihilator, which emits higher energy photons (light of shorter wavelength) as a result of TTA (Figure 1).

Finding good solid materials for PUC has proven challenging for a long time. Although liquid samples can achieve relatively high PUC efficiency, working with liquids, especially those comprising organic solvents, is inherently risky and cumbersome in many applications. However, previous trials to create PUC solids generally suffered from poor crystal quality and small crystal domains, which lead to short travelling distances of triplet excited states and thus, low PUC efficiency. Additionally, in most previous solid PUC samples, stability under continuous photoirradiation was not tested and experimental data were often acquired in inert gas atmospheres. Hence, the low efficiency and insufficient materials stability had been of concern for a long time.

Now, in a recent study led by Associate Professor Yoichi Murakami from Tokyo Tech, Japan, a team of researchers found the answer to this challenge. Published in Materials Horizon, their paper (open access) describes how they focused on van der Waals crystals, a classical materials class that has not been considered for the quest of high-efficiency PUC solids. After discovering that 9-(2-naphthyl)-10-[4-(1-naphthyl)phenyl]anthracene (ANNP), a hydrocarbon molecule originally developed for blue organic LEDs, was an excellent annihilator for embodying their concept, they tried mixing it with platinum octaethylporphyrin (PtOEP), a staple sensitizer that absorbs green light.

The team found that aggregation of the sensitizer molecules could be completely avoided by utilizing the crystalline phase of a van der Waals solid solution with a sufficiently low proportion of PtOEP to ANNP (around 1:50000). They proceeded to thoroughly characterize the obtained crystals and found some insight into why using the ANNP annihilator prevented the aggregation of the sensitizer when other existing annihilators had failed to do so in previous studies. Moreover, the solid crystals the team produced were highly stable and exhibited outstanding performance, as Dr. Murakami remarks: “The results of our experiments using simulated sunlight indicate that solar concentration optics such as lenses are no longer needed to efficiently upconvert terrestrial sunlight.”

Overall, this study brings van der Waals crystals back into the game of PUC as an effective way of creating outstanding solid materials using versatile hydrocarbon annihilators. “The proof-of-concept we presented in our paper is a major technical leap forward in the quest for high-performance PUC solids, which will open up diverse photonics technologies in the future,” concludes Dr. Murakami. Let us hope further research in this topic allows us to efficiently transform light into its most useful forms.

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New Russian module docks with International Space Station – CGTN

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A Soyuz rocket carrying the Progress cargo spacecraft and the Prichal node module lifts off from a launch pad at the Baikonur Cosmodrome, Kazakhstan, November 24, 2021. /CFP

A Soyuz rocket carrying the Progress cargo spacecraft and the Prichal node module lifts off from a launch pad at the Baikonur Cosmodrome, Kazakhstan, November 24, 2021. /CFP

A Russian cargo craft carrying a new docking module successfully hooked up with the International Space Station Friday after a two-day space journey.

The new spherical module, named Prichal (Pier), docked with the orbiting outpost at 6:19 p.m. Moscow time (1519 GMT). It has six docking ports and will allow potential future expansion of the Russian segment of the station.

The module has moored to the docking port of the new Russian Nauka (Science) laboratory module.

On Wednesday, a Soyuz rocket took off from the Russian launch facility in Baikonur, Kazakhstan, carrying the Progress cargo ship with Prichal attached to it. After entering space, the cargo ship with the module went into orbit.

Progress is also delivering 700 kilograms of various cargoes to the space station and is expected to undock from the station on December 22.

The first Soyuz spacecraft is expected to dock at the new module on March 18, 2022, with a crew of three cosmonauts: Oleg Artemyev, Denis Matveev and Sergei Korsakov.

Earlier this week, the Russian crew on the station started training for the module’s arrival, simulating the use of manual controls in case the automatic docking system failed.

The space outpost is currently operated by NASA astronauts Raja Chari, Thomas Marshburn, Kayla Barron, and Mark Vande Hei; Russian cosmonauts Anton Shkaplerov and Pyotr Dubrov; and Matthias Maurer of the European Space Agency.

Source(s): AP

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