Daily Archives: July 5, 2024

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Daybreak at the Gale Crater on Mars where organic material was found Photo: NASA/JPL-Caltech/MSSS

Credit: NASA/JPL-Caltech/MSSS

In a meteor crater on the red planet, a solitary robot is moving about. Right now it is probably collecting soil samples with a drill and a robotic arm, as it has quite a habit of doing. NASA's Curiosity rover has been active on Mars as the extended arm of science for nearly 12 years, and it continues to make discoveries that surprise and challenge scientists' understanding of both Mars and our own world here on Earth.

Most recently, the discovery of sedimentary organic material with particular properties has had many researchers scratching their heads. The properties of these carbon-based materials, in particular the ratio of its carbon isotopes, surprised researchers.

Organic materials with such properties, if found on Earth, would typically be a sign of microorganisms, but they can also be the result of non-biological, chemical processes. The find obviously had researchers scrambling for a clear answer, but nothing seemed to fit.

However, for the research collaboration behind a new studypublished in Nature Geoscience, there has been little hair scratching and much enthusiasm.

In fact, the discovery on Mars provided the missing piece that made everything fall into place for this group of researchers from the University of Copenhagen and the Tokyo Institute of Technology.

As co-author and chemistry professor Matthew Johnson puts it, it is "the smoking gun" needed to confirm a decade old theory of his about so-called photolysis in Mars' atmosphere.

With the Curiosity sample, the new research is able to prove with reasonable certainty that the Sun broke down CO2 in the Martian atmosphere billions of years ago - as the old theory predicted. And that the resulting carbon monoxide gradually reacted with other chemicals in the atmosphere synthesizing complex molecules and thus providing Mars with organic materials.

Such carbon-based complex molecules are the prerequisite of life, the building blocks of life one might say. So, this it is a bit like the old debate about which came first, the chicken or the egg. We show that the organic material found on Mars has been formed through atmospheric photochemical reactions - without life that is. This is the 'egg', a prerequisite of life. It still remains to be shown whether or not this organic materialresulted in life on the Red Planet." said Johnson and continued:

Additionally because Earth, Mars and Venus had very similar CO2 rich atmospheres long ago when this photolysis took place, it can also prove important for our understanding of how life began on Earth, said Professor Matthew Johnson from Department of Chemistry at University of Copenhagen.

Two pieces separated by 50 Million Kilometers one puzzle solved

12 years ago Johnson and two colleagues used simulations based on quantum mechanics to determine what happens when a CO2 rich atmosphere is exposed to the UV-light of the Sun, in a process known as photolysis.

Basically, on Mars around 20% of the CO2 is split into oxygen and carbon monoxide. But carbon has two stable isotopes: carbon-12 and carbon-13. Usually they are present in a ratio of one carbon-13 for every 99 carbon-12. However, photolysis works faster for the lighter carbon-12, so the carbon monoxide produced by photolysis has less carbon-13 (is depleted), and the left over CO2 has more (is enriched).

Because of this, Johnson and his colleagues were able to make very precise predictions of the ratio of carbon isotopes after photolysis. And this gave them two distinctive fingerprints to look for. One of these was identified in a different Martian sample, years ago.

We actually have a piece of Mars here on Earth, which was knocked off that planet by a meteorite, and then became one itself, when it landed here on Earth. This meteorite, called Allan Hills 84001 for the place in Antarctica where it was found, contains carbonate minerals that form from CO2 in the atmosphere. The smoking gun here is that the ratio of carbon isotopes in it exactly matches our predictions in the quantum chemical simulations, but there was a missing piece in the puzzle. We were missing the other product of this chemical process to confirm the theory, and that's what we've now obtained," says Matthew Johnson.

The carbon in the Allan Hills meteorite is enriched in carbon-13, which makes it the mirror image of the depletion in carbon-13 that has now been measured in the organic material found by Curiousity on Mars.

The new study has thus linked data from two samples, which researchers believe have the same origin in Mars' childhood but were found more than 50 million kilometers apart.

There is no other way to explain both the carbon-13 depletion in the organic material and the enrichment in the Martian meteorite, both relative to the composition of volcanic CO2 emitted on Mars, which has a constant composition, similar as for Earths volcanos, and serves as a baseline, said Johnson

Hope to find the same evidence on Earth

Because the organic material contains this isotopic fingerprint of where it came from, researchers are able to trace the source of the carbon in the organic material to the carbon monoxide formed by photolysis in the atmosphere. But this also reveals a lot about what happened to it in between.

This shows that carbon monoxide is the starting point for the synthesis of organic molecules in these kinds of atmospheres. So we have an important conclusion about the origin of lifes building blocks. Although so far only on Mars, said Matthew Johnson.

Researchers hope to find the same isotopic evidence on Earth, but this has yet to happen, and it could be a much bigger challenge because our geological development has changed the surface significantly compared to Mars, Johnson explains.

"It is reasonable to assume that the photolysis of CO2 was also a prerequisite for the emergence of life here on Earth, in all its complexity. But we have not yet found this smoking gun material here on Earth to prove that the process took place. Perhaps because Earth's surface is much more alive, geologically and literally, and therefore constantly changing. But it is a big step that we have now found it on Mars, from a time when the two planets were very similar," says Matthew Johnson.

Facts: Organic material

The sample found on Mars contains deposits of so-called organic material. To laymen this may sound more exciting than it is. Organic material in a chemical context does not necessarily mean something living, as one might normally think. The term covers molecules that contain carbon and at least one other element and can easily exist without life. These molecules are rather the building blocks of life.

Facts: What is Photolysis

Photolysis means that the Sun's UV rays provide molecules with energy to perform a chemical transformation. According to the research this happened in the Martian atmosphere, where 20% of CO2 molecules there were split into oxygen and carbon monoxide.

In earlier research, Johnson and colleagues showed that carbon dioxide containing the carbon-12 isotope is photolysed more quickly than the heavier isotope carbon-13.

Over time, CO is produced that is depleted in 13C, and 13C builds up in the remaining CO2. This results in so-called isotopic enrichment in CO2 and depletion in CO, like mirror images or each other or the two halves of a broken plate.

It is the fractionation ratio in carbon, which serves as evidence of photolysis in the two samples from Mars.

Facts: The oxygen painted Mars red

Photolysis of a CO2 molecule yields carbon monoxide (CO) and an oxygen atom (O). On Mars, only carbon monoxide remains, which is transformed into the organic material found by the Curiosity rover.

But where the oxygen has gone is also no secret. The oxygen combines into O2, which interacts with iron on Mars' surface. The Red Planet is rust red due to oxidized iron.

Facts: Isotopes Have Different Weights

Isotopes are variants of the same element that have different weights because the nucleus contains more or fewer neutrons.

Carbon has two stable isotopes - Normally, about 99% of carbon has 6 protons and 6 neutrons in its nucleus (12C). About 1% has 6 protons and 7 neutrons instead (13C). The ratio can serve as a chemical fingerprint revealing what reactions the carbon has undergone.

Photolysis favors carbon-12, and a high concentration of the isotope can therefore indicate this process.

Extra Info: The Famous Mars Meteorite

The discovery of organic sediments on Mars with a low ratio of carbon-13 completes the puzzle of empirical evidence for the photolysis theory, since researchers already found the other part of that puzzle years ago in the famous meteorite, Allan Hills 84001. The meteorite contains carbonate with a heightened concentration of heavy carbon 13 isotopes.

Discovered in Antarctica 40 years ago by Roberta Score, the meteorite is believed to originate from the Red Planet and became particularly well known because it contains some deposits that led NASA researchers to announce in 1996 that they believed they had found traces of microscopic fossils of bacteria from Mars.

Today, the consensus is that these deposits are abiotic - that is, stemming from non-biological processes.

Extra info: Mars, Earth, and Venus Had the Same Atmosphere

According to researchers, Earth had approximately the same atmosphere as our neighboring planets Mars and Venus billions of years ago.

When the early planets Venus, Earth, and Mars eventually formed solid surfaces, researchers believe they began to release large amounts of CO2 from extreme volcanic activity. That's how they formed their first atmospheres with large concentrations of the gas. Oxygen had not yet become part of the atmosphere; this happened later on Earth, after the emergence of life.

The photolysis theory states that UV rays from the sun then start a chain of chemical reactions. A chain that starts with the breakdown of CO2 into carbon monoxide, which is the building block for a multitude of other chemical compounds.

Thus, with the help of the Sun, the foundation for the many carbon compounds and complex molecules we have today was formed - in the case of Earth, the foundation for life.

"Since then the fate of the three planets has been significantly different. Earth's carbon dioxide reacted with our large amount of surface water and much of it deposited over time as carbonate rocks like limestone, leaving the atmosphere dominated by nitrogen, as we have today. Life arose, and microorganisms produced oxygen, which, among other things, created our ozone layer, while Mars and Venus still have very CO2-dominant atmospheres today," explains Matthew Johnson.

Today, Venus has a very dense and toxic atmosphere primarily of CO2, which gives it a surface temperature of around 450 degrees Celsius.

On Mars, the atmosphere has become much thinner compared to Earth's, and has left a desert landscape.

About the new study:

The study is published in Nature Geoscience and has just appeared in the journal's June issue.

The following researchers have contributed to the new study:

From the Department of Chemistry at the University of Copenhagen:

Matthew S. Johnson and Johan A. Schmidt

From the Tokyo Institute of Technology:

Yuichiro Ueno, Xiaofeng Zang, Alexis Gilbert, Hiroyuki Kurokawa and Tomohiro Usui

From the University of Tokyo and the Royal Belgian Institute of Space Aeronomy:

Shohei Aoki

Nature Geoscience

Synthesis of 13C-depleted organic matter from CO in a reducing early Martian atmosphere

9-May-2024

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Organic material from Mars reveals the likely origin of life's building blocks - EurekAlert

Using the orbiters circling the planet and rovers driving across its surface, astronomers captured the effects of a massive solar storm on Mars in order to better estimate the radiation levels that the first red planet astronauts may experience in the future.

According to NASA, the giant solar storm that hit Mars this May engulfed the planet with auroras and an influx of charged particles and radiation. After a massive cluster of sunspots faced the Earth, they rotated in the direction of Mars.

Within the past several months, the sun has shown increased activity as it nears the peak of its 11-year cycle which is predicted for later this year, also known as solar maximum. The spike in solar activity has included strong solar flares, X-class flares, and coronal mass injections or large clouds of ionized gas called plasma and magnetic fields that erupt from the suns outer atmosphere.

According to data from the Solar Orbiter spacecraft, the most severe storm took place on May 20 when an X12 flare was released from the sun. The flare sent X-rays and gamma rays toward Mars and a coronal mass ejection released on the heels of the flare, sending charged particles in the planets direction.

Scientists from NASAs Moon to Mars Space Weather Analysis Office at the Goddard Space Flight Center in Greenbelt, Maryland stated that the X-rays and gamma rays traveled at the speed of light and reached Mars first, followed by charged particles approximately ten minutes later.

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Solar Storm Hits Mars and Highlights Risks for Future Missions - Tomorrow's World Today

NASAs InSight Mars Lander faced some challenges during its time on the red planets surface. Its mole instrument struggled to penetrate the compacted Martian soil, and the mission eventually ended when its solar panels were covered in dust. But some of its instruments performed well, including SEIS, the Seismic Experiment for Interior Structure.

SEIS gathered Mars seismic data for more than four years, and researchers working with all of that data have determined a new meteorite impact rate for Mars.

SEIS was designed to probe Mars interior structure by measuring seismic waves from Marsquakes and impacts. It measured over 1300 seismic events. Theres no way to absolutely measure how many of them were from impacts, but scientists working with the data have narrowed it down.

Their results are in new research published in Nature Astronomy titled An estimate of the impact rate on Mars from statistics of very-high-frequency marsquakes. The lead authors are Graldine Zenhusern and Natalia Wjcicka, from the Institute of Geophysics, ETH Zurich, and the Department of Earth Science and Engineering, Imperial College, London, respectively.

This is the first paper of its kind to determine how often meteorites impact the surface of Mars from seismological data.

Though SEIS was an effective instrument, it couldnt always tell what each seismic event was. Only a handful of the events it detected were powerful enough to determine their location. However, six events in close proximity to the InSight lander were confirmed as meteorite impacts because they were correlated with acoustic atmospheric signals that meteors make when they enter Mars atmosphere. The six events belong to a larger group called very high-frequency (VF) events.

While the source process for a typical marsquake measuring magnitude 3 takes several seconds, an impact-generated quake takes much less time because of the collisions hypervelocity. These are the VF events.

During about three years of recording time, InSight and SEIS detected 70 VF events. 59 of them had good distance estimates, and according to the researchers, a handful of them were higher quality B VF events, meaning their signal-to-noise ratios are strong. Although a non-impact origin cannot be definitively excluded for each VF event, we show that the VF class as a whole is plausibly caused by meteorite impacts, the authors explain in their paper.

This led to a new estimate of Marss impact frequencies. The researchers say that between 280 and 360 meteoroids about the size of basketballs strike Mars each year and excavate craters greater than 8 meters (26 ft) in diameter. Thats almost one every day at the upper end. This rate was about five times higher than the number estimated from orbital imagery alone. Aligned with orbital imagery, our findings demonstrate that seismology is an excellent tool for measuring impact rates, Zenhusern said in a press release.

Impact rates on different bodies in the Solar System are one way of understanding the age of their surfaces. Earths surface is young because the planet is so geologically active. Earth is also much easier to study in greater detail, for obvious reasons. But for bodies like the Moon and Mars, impact rates can tell us the ages of various surfaces, leading to a more thorough understanding of their history.

Orbital images and models based on preserved lunar craters have been the main tools used by planetary scientists to infer impact rates. The data from the Moon was used to extrapolate Mars impact rate. But there are problems with that method. Mars has more powerful gravity and is closer to the source of most meteors, the asteroid belt.

That means more meteoroids strike Mars than the Moon, and that had to be calculated somehow. Conversely, Mars has widespread dust storms that can obscure craters in orbital images, while the lunar surface is largely static. Mars also has different types of surface regions. In some regions, craters stand out; in others, they dont. Trying to accurately account for that many differences when extrapolating impact rates from the Moon to Mars is challenging.

This work shows that seismometers can be a more reliable way to understand impact rates.

We estimated crater diameters from the magnitude of all the VF-marsquakes and their distances, then used it to calculate how many craters formed around the InSight lander over the course of a year. We then extrapolated this data to estimate the number of impacts that happen annually on the whole surface of Mars, Wjcicka explained.

While new craters can best be seen on flat and dusty terrain where they really stand out, this type of terrain covers less than half of the surface of Mars. The sensitive InSight seismometer, however, could hear every single impact within the landers range, said Zenhusern.

These results extend beyond Mars. Understanding Mars also helps us understand the wider Solar System. The current meteoroid impact rate on Mars is vital for determining accurate absolute ages of surfaces throughout the Solar System, the authors write in their paper. Without accurate surface ages, we dont have an accurate understanding of the Solar Systems history.

Now we know that an 8-metre (26-feet) crater is excavated somewhere on Mars surface almost daily, and a 30-metre (98-feet) crater is a monthly occurrence. But its about more than just crater size. These hypervelocity impacts create blast zones that dwarf the crater itself. The blast zones can easily be 100 times larger than the crater. So, a better understanding of impact rates can make robotic missions and future human missions safer.

The higher overall number of impacts and the higher relative number of small ones found in our study show that meteoritic impacts might be a substantial hazard for future explorations of Mars and other planets without a thick atmosphere, the authors write in their conclusion.

This study is a win for InSight and SEIS and for the researchers who pieced this together.

This is the first paper of its kind to determine how often meteorites impact the surface of Mars from seismological data which was a level one mission goal of the Mars InSight Mission, says Domenico Giardini, Professor of Seismology and Geodynamics at ETH Zurich and co-Principal Investigator for the NASA Mars InSight Mission. Such data factors into the planning for future missions to Mars.

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Basketball-Sized Meteorites Strike the Surface of Mars Every Day - Universe Today

NASA is concluding a yearlong Mars mission experiment and four volunteers are set to leave a simulated Mars habitat that they've been living in since June of last year.

NASA's Crew Health and Performance Exploration Analog experiment was built to research how to keep astronaut crews healthy and productive during long missions to Mars. It took place in a 1,700 square-foot 3D-printed habitat that mimics the conditions crews will face during a Mars mission.

On June 25, 2023, Kelly Haston, Anca Selariu, Ross Brockwell and Nathan Jones entered the habitat and have been inside ever since.

They have run science experiments, practiced mock Marswalks and even farmed some of their own food, bringing a bit of Earth's green with them.

Salad crop production may supplement the packaged meals, reduce menu fatigue, and provide a creative outlet for the crew to add a variety of fresh produce to their diet, said NASA's Gioia Massa, who leads the experiment's farming team. Growing plants may also provide psychological benefits for astronauts living in isolated, confined environments away from Earth, and we hope to capture data on both of these aspects.

In addition to their experiments and tests, the crew dealt with the other realities of a Mars mission, including isolation, simulated equipment failures and intentionally delayed communications with the rest of Earth. During a real mission, radio signals can take more than 20 minutes to go one way between Earth and Mars, which means real-time communications aren't possible.

The crew is set to return to the outside world on Saturday, July 6. NASA will be streaming the event.

NASA plans to run two more yearlong experiments in the habitat. The next mission will begin in Spring of 2025.

Related story: NASA astronauts will stay at space station longer for more troubleshooting of Boeing capsule

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A NASA crew is about to finish a yearlong Mars mission isolation experiment - Scripps News

For a brief time this month, Taurus will appear to have two eyes as Mars (upper left) moves northwest of Aldebaran (below center), as in this 2023 photo. Comet C/2022 E3 (ZTF) is also visible here, to Aldebarans lower left. Credit: Alan Dyer

The planets are spreading out this month. Mercury and Venus lie in the evening sky; after midnight the next set of planets rises one after the other, led by Saturn. Its followed into the early-morning sky by Neptune, Mars, Uranus, and Jupiter. Saturn in particular is stunning, with the rings at their narrowest for the year.

First to set after the Sun on July 1 is Venus. Its a challenging object to find, disappearing within 30 minutes of sunset. If you have a very clear western horizon, look for the magnitude 3.9 planet in bright twilight, standing only 2 high 15 minutes after sunset.

Try again on July 6, when the crescent Moon appears 7 high about 20 minutes after sunset. Venus lies 5 below it and once again sets quickly.

By the end of July, Venus is nearly 16 east of the Sun but still hugs the horizon from northern temperate latitudes. It stands 3 high 30 minutes after sunset, and those scanning the horizon with binoculars might spot 1st-magnitude Regulus, Leos brightest star, 5 east of the planet. Mercury is also present, at the same altitude as Venus and 4.7 south of Regulus, shining at magnitude 0.9.

Rewinding a bit, Mercury shines in the evening sky at magnitude 0.6 on July 1. A healthy 18.5 from the Sun, it remains 7 high 30 minutes after sunset. As the sky darkens, Mercury will be an easy object to catch. Watch for Castor and Pollux, Geminis pair of 1st-magnitude stars, which stand at the same altitude above the horizon northwest of Mercury.

Mercury slides away from the pair of stars quickly and by July 7, the waxing Moon stands 3 above Mercury a beautiful sight in twilight. Look for earthshine illuminating the dark hemisphere of the Moon.

Mercury fades as it increases its distance from the Sun and reaches its greatest eastern elongation of 27 on July 22. It has now dimmed to magnitude 0.5 and stands within 3 of Regulus. The planet has become more challenging to find. Mercury stands 5 high 40 minutes after sunset, a good time to spot it.

Due to the low angle of the ecliptic to the horizon in the Northern Hemisphere, this isnt as favorable as elongations that occur in March. Southern Hemisphere observers will have a better view.

Saturn rises at midnight on July 1, located in northeastern Aquarius just 2.1 from Phi () Aquarii. Its easy to spot at magnitude 0.9. The ringed world barely moves at first, then slowly progresses along its retrograde path and ends the month within 1.5 of Phi.

On July 24, a waxing gibbous Moon stands about 7 west of Saturn. Later in the day for regions in Africa, Asia, and Indonesia, the Moon occults Saturn. The planet brightens to magnitude 0.7 by the end of July in preparation for Septembers opposition.

The rings appear very fine and nearly edge-on through a telescope, tilted by only 2 to our line of sight. Its disk spans 18 and the wide axis of the rings stretches roughly 41 across. Through the end of the year, the rings will widen before closing again and appearing edge-on in March 2025.

Now that the ring plane is almost edge-on, Saturns satellites cross in front of or behind the planet. Titan, the brightest moon at magnitude 8.5, orbits every 16 days. The moon is occulted by Saturn July 8 around 2:40 a.m. EDT (not visible in the Pacific time zone). It takes several minutes to disappear, so begin watching 10 to 20 minutes earlier. A second occultation occurs July 24 around 1:30 a.m. EDT (not visible in Mountain or Pacific time zones).

On July 16, Titan begins a transit across Saturn just before 2:30 a.m. EDT (again, not visible on the West Coast). The transit lasts nearly four hours, with egress occurring around 4:20 a.m. MDT (in daylight for the East Coast and nearly sunrise in the Midwest).

The transit starting July 31/Aug. 1 at 1:15 a.m. EDT is the first easily seen from the Mountain time zone, although Saturn is at an elevation of only 13.

Dione begins a transit an hour later, led by its shadow, which appears behind Titan on the cloud tops an extraordinary alignment. Dione is a small moon that shines at 10th magnitude, so its difficult to see against the bright background of Saturn. Its easier to capture using high-speed video and image-refining techniques.

Several moons also skim the edge of the rings as seen from Earth, although these are also difficult to observe. Again, high-resolution imaging can catch these events.

Iapetus orbits at a much greater distance from Saturn every 79 days. It moves 1 north of Saturn on July 6, reaching inferior conjunction as it heads toward western elongation on the 27th. Between early July and this date, Iapetus brightens from about 11th magnitude to magnitude 10.2.

Neptune is in southwestern Pisces, some 5 southeast of Lambda () Piscium in the Circlet. It rises around midnight and reaches a good height in the eastern sky by 2 a.m. local daylight time. As you scan with binoculars, look for a parallelogram of 4th- to 5th-magnitude stars. The northernmost bright one is 29 Psc; much dimmer Neptune lies nearly 2 to its north. Neptune shines at magnitude 7.7.

On July 25, the waning gibbous Moon stands about 4.5 southwest of Neptune two hours after rising. By dawn theyre less than 3 apart. Neptune reaches its stationary point early in July and the planet barely moves all month.

The next planet up is Mars, rising just after 2 a.m. local daylight time on July 1 with a waning crescent Moon. The Red Planet shines at magnitude 1 in southeastern Aries, 15 from the Pleiades (M45). Mars moves into Taurus by July 12.

Mars is closing in on Uranus, also in western Taurus, and theyre just over 2 apart on the 12th. Look again on July 15, when Mars and Uranus stand only 0.6 apart. Binoculars will reveal the dim, greenish-blue-hued disk of Uranus due north of Mars. Uranus shines at magnitude 5.8. The pair now stand 6 southwest of the Pleiades. Check each consecutive night as Mars pulls away from Uranus, moving about 0.7 east per day.

On July 20, Mars stands 4.8 due south of M45. By the 22nd, its brightened to magnitude 0.9. Mars continues eastward and at the end of July stands 5.5 northwest of Aldebaran, matching the star in magnitude. For a time, Taurus the Bull appears to have two eyes. A waning crescent Moon joins Mars a day earlier, on July 30. Along with M45 and Jupiter, also in Taurus, the view is spectacular.

Through a telescope, Mars is a challenging 6 across and stands 30 high in the east as twilight begins on July 31.

Uranus remains near the western edge of Taurus all month. Its disk spans only 3 through a telescope, challenging to see unless conditions are excellent. Once Mars has left the scene, you can spot Uranus in binoculars 2 west of a pair of 6th-magnitude stars, 13 and 14 Tauri, which are less than 0.4 apart and about 4.5 due south of the Pleiades.

Jupiters visibility improves each day as it climbs higher in the pre-dawn sky. The gas giant rises around 3:30 a.m. local daylight time on July 1, north of the Hyades star cluster in Taurus. A waning crescent Moon joins it July 3. By the 13th, Jupiter stands 5 due north of Aldebaran. The crescent Moon again joins Jupiter July 30 and 31. The planet starts the month at magnitude 2 and brightens by 0.1 magnitude by July 31, now rising before 2 a.m.

Through a telescope, Jupiter spans 35 and is joined by the four Galilean moons, Io, Europa, Ganymede, and Callisto. Catching a transit or occultation is a great way to start a summer morning.

Early on July 4, Ganymede transits Jupiters south polar region. The event is underway as Jupiter rises in the western U.S. Ganymede slowly exits the disk around 5:50 a.m. MDT in twilight, while its still dark in the Pacific time zone.

Io and Europa put on a pair of events the morning of July 6. Europas transit begins at 4:42 a.m. EDT, visible from the eastern U.S. The moons shadow is already nearly done with a transit, approaching the western limb. As Jupiter rises farther west, Ios shadow starts to transit at 5:15 a.m. CDT, as twilight encroaches on the Midwest. Observers in the western U.S. will see Io begin its transit at 5:02 a.m. MDT, with Europa exiting the disk minutes later, around 5:12 a.m. MDT.

Ganymedes huge shadow crosses Jupiters south polar region July 11 between 4:52 a.m. and 6:40 a.m. MDT. (The exit occurs in daylight for the Mountain time zone but twilight in the Pacific time zone.) Europas shadow crosses the disk July 13, starting around 5:15 a.m. EDT, as Europa closes on Jupiters eastern limb and begins its own transit around 5:30 a.m. MDT.

One of the most interesting events of the month is the transit of Io with its shadow as Ganymede reappears from eclipse on July 22. The first pair of events is better observed across the eastern half of the U.S. Ios shadow begins a transit at 4:31 a.m. EDT (when Jupiter is only 10 high in the Midwest). Ganymede is occulted by Jupiters northwestern limb seven minutes later. Meanwhile, Io is approaching the eastern limb and begins to transit at 5:31 a.m. EDT. Ganymede passes behind Jupiter and reappears around 4:36 a.m. MDT, in bright twilight for the Midwest.

Another set of events occurs July 29. Ganymede enters Jupiters extended shadow west of the planet just before 4:40 a.m. EDT, followed by Europa just over an hour later, shortly before sunrise in the Eastern time zone. Then, Ios shadow begins a transit at the eastern limb at 5:25 a.m. CDT. Within minutes, Ganymede exits the shadow still northwest of Jupiter at 5:28 a.m. CDT, a process that takes a few minutes. Watch it brighten as Ios shadow moves onto the cloud tops. Io itself begins to transit around 5:30 a.m. MDT, now in bright twilight across the Mountain time zone but well seen in Pacific states.

A lazy, hazy summer night is the perfect time to relax your scientific gaze and let your mind wander, your eyes meandering slowly along the day-night lunar zone we call the terminator. You may have seen the more famous Lunar X or V, examples of a clair-obscur effect when the play of light and shadow bring to mind a letter, number, animal, face, or other object. But will you see a rack of pool balls July 16th, just west of the crater Delisle?

In reality, this is a clump of peaks left over from the giant impact that carved out Mare Imbrium, towering above the plains of lava that welled up afterward. Yet our earthbound brains crave familiarity in a foreign land. A couple of hours later, another region west of Mons Gruithuisen Gamma suggests an upturned sink or bathtub to some observers.

If this pareidolia tickles your fancy, do a search for Moon clair-obscur lunarism to find dozens of blogs and videos with dates and times that focus on these features. Mike Rowles has compiled a list of 99 such lunarisms some you can see two nights in a row, others fleetingly for an hour or two. Relive that childhood enjoyment of seeing shapes in clouds.

July begins quietly on the meteor shower front, with rates increasing toward the end of the month as the early Perseids begin and the Southern Delta Aquariid shower reaches its peak. The latter is active from July 12 through Aug. 23 and peaks on July 31, although activity is fairly broad across a few days on either side of this date.

The radiant is near the star Skat in Aquarius, which reaches 30 elevation around 3 a.m. local daylight time, resulting in observed rates of about half the predicted zenithal hourly rate of 25 meteors per hour. The waning crescent Moon will have some effect on the visibility of fainter meteors.

The Southern Delta Aquariids are the result of Comet 96P/Machholz. This is 1 of 8 showers related to the comet, which has a 5.3-year orbital period.

The best two comets of the night are sinking below 15 altitude by sunset, so be on target as darkness arrives. Head straight south of Leos tail to get to C/2023 A3 (Tsuchinshan-ATLAS). On track to blow our socks off in October, it currently glows at a modest 8th magnitude and should sport a faint eastward tail if skies are dark and transparent enough. Approaching Mars orbit, the carbon atoms released with its dust are just turning on for imagers to catch a classic green coma. By the end of July, the comet is swallowed by twilight see you in three months!

Quickly swing northwest to the feet of Ursa Major, where 13P/Olbers is traveling through Lynx and Leo Minor. It reached perihelion June 29 and will give us three more months of telescopic viewing. Binocular observers, challenge yourself to find the 8th-magnitude glow. Push the magnification past 100x and note that Olbers should be lopsided compared to spiral galaxy NGC 2841, some 9 to the north on July 8. Whose core is sharpest and brightest?

Need an overnight comet? Bring along a good chart to help you navigate the forest of 7th-magnitude stars between Cepheus and Draco to get to the challenging 10th-magnitude C/2021 S3 (PanSTARRS).

Within reach of binoculars from the suburbs, dwarf planet 1 Ceres gives us a nice and easy asteroid search this summer. Stargazers familiar with the heart of the galaxy know the collection of stars called the Teapot of Sagittarius. Magnitude 2.6 Zeta () Sagittarii anchors the base of the Teapots handle and will be our signpost to find Ceres.

The large dwarf planet (roughly 600 miles across) reflects the most sunlight at opposition on the 5th, raising it to magnitude 7.3 and leaving it largely uncontested in the eyepiece by the legions of fainter stars toward the galaxys hub. You can track its nightly shift against the background by penciling three or four stars onto a logbook sheet and returning an evening or two later to confirm the point that moved.

On the 20th, Ceres is sliding away from a trapezoid of stars (fainter than the limiting magnitude below); if you stay up late you might notice its tiny shift. For a laugh, can you see it on the 19th, a mere two lunar diameters south of the nearly Full Moon?

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What's in the sky this month? Look for Mercury and Venus in the evening, then Neptune, Mars, Uranus, and Jupiter - Astronomy Magazine

The addition of a small amount of water saw the moss bounce back to life within seconds and resume photosynthesis, turning carbon dioxide into the oxygen and carbohydrates essential to human survival on any planet, the researchers wrote.

It represents a promising candidate as a colonist to facilitate terraforming on Mars and help drive the atmospheric, geological, and ecological processes required for other higher plants and animals.

The findings attracted the attention of astrobiologist Lin Wei from the Institute of Geology and Geophysics in Beijing, who described them as very interesting and valuable.

With a series of scientific experiments, the team demonstrated that Syntrichia caninervis could survive for one week in a simulated Martian environment, said Lin, who was not involved in the study.

The papers lead author, Li Xiaoshuang, a cell biologist from the Xinjiang Institute of Ecology and Geography, told the South China Morning Post that she had been studying the magic plant for two decades.

The desert moss was known for its outstanding resistance to drought and radiation, she said. Most plants would die if they lost 30 per cent of their cell water. This one survives after complete dehydration.

Li and her team spent a long time looking for drought-resistance genes in the moss, which they hoped would help other plants grow better in really dry environments until they accidentally discovered that it also thrives under ice in winter.

I got really curious and started putting it in freezers and then liquid nitrogen tanks, Li said. It really stood out as the only plant to have demonstrated such extraordinary resistance to different environmental stressors.

The research established that the moss could regenerate under normal growth conditions after spending five years at -80 degrees Celsius (-112 Fahrenheit) and 30 days at -196 Celsius (-320.8 Fahrenheit).

Eventually, the researchers took some moss samples to a simulation cabin at the National Space Science Centre in Beijing to test their ability to endure Mars-like conditions.

The simulator was preset to an air composition of 95 per cent carbon dioxide, temperature range between -60 and 20 Celsius (-76 and 68 Fahrenheit), and radiation levels similar to those found on the surface of Mars.

01:08

Chinas Zhu Rong rover discovers evidence of an ancient sea on Mars

Chinas Zhu Rong rover discovers evidence of an ancient sea on Mars

Li and her team found that the dried moss plants fully recovered within 30 days after exposure to Martian conditions for one, two, three, and seven days. Hydrated plants exposed to the simulator for one day also survived, but regenerated more slowly.

According to Li, the team has already planted the moss in a replica of the soil found on Mars. It grew really well, and all it needed was water, she said.

Next, Li and her team will be looking for opportunities to send moss samples into outer space for exposure experiments, or even to the surface of the moon or Mars.

Mosses were the first embryophyte to leave the ocean and colonise land in Earths history. We are curious to see if colonisation could happen again on Mars, she said.

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Chinese scientists find diehard moss that might survive and thrive on Mars - South China Morning Post

NASA has released two white papers associated with the agencys Moon to Mars architecture efforts. The papers, one on lunar mobility drivers and needs, and one on lunar surface cargo, detail NASAs latest thinking on specific areas of its lunar exploration strategy.

While NASA has established a yearly cadence of releasing new documents associated with its Moon to Mars architecture, the agency occasionally releases mid-cycle findings to share essential information in areas of interest for its stakeholders.

Lunar Mobility Drivers and Needs discusses the need to move cargo and assets on the lunar surface, from landing sites to areas of use, and some of the factors that will significantly impact mobility systems.

Lunar Surface Cargo analyses some of the current projected needs and identifies current capability gaps for the transportation of cargo to the lunar surface.

The Moon to Mars architecture approach incorporates feedback from U.S. industry, academia, international partners, and the NASA workforce. The agency typically releases a series of technical documents at the end of its annual analysis cycle, including an update of the Architecture Definition Document and white papers that elaborate on frequently raised topics.

Under NASAsArtemiscampaign, the agency will establish the foundation for long-term scientific exploration at the Moon, land the first woman,first person of color, and its first international partner astronaut on the lunar surface, and prepare for human expeditions to Mars for the benefit of all.

You can find all of NASAs Moon to Mars architecture documents at:

https://www.nasa.gov/moontomarsarchitecture

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NASA Shares Two New Moon to Mars Architecture White Papers - NASA

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Researchers have figured out the first estimate of global meteorite impacts on Mars using seismic data.

Their findings indicate between 280 to 360 meteorites strike the planet each year forming impact craters greater than 8 meters (about 26 feet) across.

This rate was about five times higher than the number estimated from orbital imagery alone, says Graldine Zenhusern of ETH Zurich, who co-led the study. Aligned with orbital imagery, our findings demonstrate that seismology is an excellent tool for measuring impact rates.

Using data from the seismometer deployed during the NASA InSight Mission to Mars, researchers found that 6 seismic events recorded in the near proximity of the station had been previously identified as meteoric impactsa process enabled by the recording of a specific acoustic atmospheric signal generated when meteorites enter the Martian atmosphere.

Now, co-lead Zenhusern of ETH Zurich, Natalia Wjcicka of Imperial College London, and the research team have found that these 6 seismic events belong to a much larger group of marsquakes, so called very high frequency (VF) events.

The source process of these quakes occurs much faster than for a tectonic marsquake of similar size. Where a normal magnitude 3-quake on Mars takes several seconds, an impact-generated event of the same size takes only 0.2 seconds or less, due to the hypervelocity of the collision. By analysing marsquake spectra, a further 80 marsquakes were identified that are now thought to be caused by meteoroid strikes.

Their research quest began in December 2021, a year before accumulated dust on the solar panels put an end to the InSight mission, when a large distant quake recorded by the seismometer reverberated a broadband seismic signal throughout the planet. Remote sensing associated the quake with a 150-meter-wide crater.

To confirm, the InSight team partnered with Mars Reconnaissance Orbiter (MRO) Context Camera (CTX) to search for other fresh craters that would match the timing and location of the seismic events detected by InSight.

The teams detective work paid off and they were lucky to find a second fresh crater over a 100-meters (320 feet) in diameter. Smaller craters, however, formed when basketball-sized meteoroids strike the planet and which should be far more common, remained elusive.

Now, the number of meteorite strikes is newly estimated by the occurrence of these special high-frequency quakes.

Approximately 17,000 meteorites fall to Earth each year, but unless they streak across the nights sky, they are rarely noticed. Most meteors disintegrate as they enter Earths atmosphere, but on Mars the atmosphere is 100 times thinner leaving its surface exposed to larger and more frequent meteorite strikes.

Until now, planetary scientists have relied on orbital images and models inferred from well-preserved meteorite impact craters on the Moon but extrapolating these estimates to Mars proved challenging.

Scientists had to account for the stronger gravitational pull of Mars and its proximity to the asteroid belt, which both mean that more meteorites hit the red planet. On the other hand, regular sandstorms result in craters that are much less well-preserved than those on the Moon, and, therefore, not as easily detected with orbital imagery.

When a meteorite strikes the planet, the seismic waves of the impact travel through the crust and mantle and can be picked up by seismometers, which provides an entirely new way of measuring Mars impact rate.

We estimated crater diameters from the magnitude of all the VF-marsquakes and their distances, then used it to calculate how many craters formed around the InSight lander over the course of a year, says Wjcicka. We then extrapolated this data to estimate the number of impacts that happen annually on the whole surface of Mars.

While new craters can best be seen on flat and dusty terrain where they really stand out, this type of terrain covers less than half of the surface of Mars, says Zenhusern. The sensitive InSight seismometer, however, could hear every single impact within the landers range.

Much like the lines and wrinkles on our face, the size and density of craters from meteorite strikes reveal clues about the age of different regions of a planetary body. The less craters, the younger the region of the planet.

Venus, for example, has almost no visible craters because it is protected by a think atmosphere and its surface is continually reworked by volcanism, the ancient surfaces of Mercury and the Moon are heavily cratered.

Mars falls in between these examples, with some old and some young regions that can be distinguished by the number of craters.

New data shows, an 8-meter (26-feet) crater happens somewhere on the surface of Mars nearly every day and a 30-meter (98-feet) crater occurs about once a month. Since hypervelocity impacts cause blast zones that are easily 100 times larger in diameter than the crater, knowing the exact number of impacts is important for the safety of robotic, but also future human missions to the red planet.

This is the first paper of its kind to determine how often meteorites impact the surface of Mars from seismological datawhich was a level one mission goal of the Mars InSight Mission, says Domenico Giardini, professor of seismology and geodynamics at ETH Zurich and co-principal investigator for the NASA Mars InSight Mission. Such data factors into the planning for future missions to Mars.

According to Zenhusern and Wjcicka, the next steps in advancing this research involve the use of machine learning technologies to aid researchers in identifying further craters in satellite images and identifying seismic events in the data.

The researchers work appears in four papers, one in Nature Astronomy, one in Science Advances, one in Science, and one in Nature Geoscience.

Source: ETH Zurich

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Meteorites the size of basketballs hit Mars almost every day - Futurity: Research News

Watch out, tardigrades: The first life form to colonize Mars may be a hardy desert moss, according to a recent study.

A team of researchers recently put a desert moss called Syntrichia caninervis through a barrage of tests, from years in a deep freeze to blasts of gamma and ultraviolet radiation, in a simulated version of Marss thin, mostly-carbon dioxide atmosphere. And the moss survived it all. According to the study, that means S. caninervis, also called steppe screw moss, may eventually be able to grow on Mars and even help terraform the cold, dry planet.

S. caninervis represents a promising candidate as a colonist to facilitate terraforming efforts on Mars or other planets, write Chinese Academy of Sciences ecologist Xiaoshuang Li and his colleagues, who published their work in the journal The Innovation.

After spending up to 5 years in deep deep freezers at -112 degrees Fahrenheit for up to 5 years, most plants would be dead, but when Li and his colleagues thawed out their samples of S. caninervis, the moss recovered within a few days and even grew new branches. Li and his colleagues blasted other samples with 500 grays (units of ionizing radiation) of gamma radiation. This is about ten times higher than the dose required to kill humans pretty much immediately. The moss not only survived, but thrived: Radiation-blasted samples grew more new branches than control samples. Sort of like the Hulk, if Bruce Banner were a tiny plant.

Scientists have spent decades looking for organisms that could survive in the vacuum of space or on the surface of Mars for decades now and trying to figure out how they do it. Bacteria, spores from fungi and plants, and even the iconic tardigrade (reigning champion of surviving horrible conditions) have spent weeks at a time exposed to the vacuum of space (meaning no air or pressure) in experiments on the outside of the International Space Station, for example. But Li and his colleagues experiments are the first time a whole plant has survived anything like conditions on the surface of Mars.

That means surviving with little or no air or at least what we humans think of as air. Almost all the air on Mars is actually carbon dioxide, which we cant breathe, but plants can. On the other hand, Marss atmosphere is extremely thin; on the ground, Martian air pressure is only about 1 percent of the air pressure at sea level here on Earth. You dont think about the weight of the whole atmosphere pressing down on you very often, but without it, liquid water would boil into steam in an instant (which would be very unpleasant for you, a creature made of about two-thirds water).

Surviving Mars also means being bombarded with radiation, because the thin Martian atmosphere doesnt offer much protection from ultraviolet or gamma rays. It also means enduring intense cold, down to about -70 degrees Fahrenheit. Li and his colleagues put some S. caninervis in a tank that simulated those conditions for about a week, and afterwards, the moss recovered and grew again.

Here on Earth, S. caninervis lives in some of the coldest and driest places on Earth, like Tibet, Antarctica, and the Arctic Circle. Thats why Li and his colleagues thought it might be a good candidate to help Earth life gain a green foothold on Mars and turn the planet into a livable place.

S. caninervis can help drive the atmospheric, geological, and ecological processes required for other higher plants and animals while facilitating the creation of new habitable environments conducive to long-term human settlement, write Li and his colleagues.

And theres good reason to imagine moss as a future terraformer, because the first plants to colonize land here on Earth were mosses.

The moss rebounded from everything Li and his colleagues simulated Mars could throw at it, but there are a couple of slight catches. As Li and his colleagues acknowledge, there is still a long way to go to create self-sufficient habitats on other planets.

First, dont picture a green, fluffy carpet of moss, happily living its best mossy life in freezing temperatures with no water. Instead, picture a clump of dried-out brown moss, waiting patiently until the weather turns warmer and nearby ice melts enough to sprinkle it with water. S. caninervis, like many other mosses, can force most of the water out of its cells to wait out freezes, droughts, and even bursts of high-energy radiation. When the moss senses nearby water and a comfier environment, it can regenerate and start growing again.

That means that if we planted a patch of S. caninervis somewhere on Mars, it would pretty much just sit there and look dead until we found a way to water it without the water immediately boiling away in Marss thin atmosphere. But its a start.

Li and his colleagues also noticed that moss samples recovered faster if theyd been dried out before being hit with the deep freeze and radiation tests, although even moss that started out without that advantage did recover.

Looking to the future, we expect that this promising moss could be brought to Mars or the Moon to further test the possibility of plant colonization and growth in outer space, write Li and his colleagues.

Of course, thats fraught territory, since at the moment were still trying to figure out whether Mars was ever home to life of its own. Contaminating the place with Earth life, especially Earth life that might actually survive there, is high on the list of things most space agencies want to avoid for the foreseeable future. Any mission that eventually does take moss or any other living samples to Mars is probably going to have strict protocols to follow to keep from giving the planet any Earth cooties.

Meanwhile, though, the Moon might be a better place, since it was never home to life of its own and its unlikely anything could actually gain a foothold there. And moss samples on the Moon would at least have some tardigrades for company.

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This Humble Plant Species May Be the Key to Terraforming Mars - Inverse

In a universe full of mysteries, our neighboring planet Mars houses a few of its own. The Red Planet has been a focal point of research for scientists worldwide, and the latest findings are nothing less than fascinating, revealing a daily dose of space basketball meteorites.

Under the expert leadership of scientists from ETH Zurich and Imperial College London, an international research team has unveiled a startling phenomenon: Mars experiences meteorite impacts nearly every day.

This discovery uses seismic data to estimate the global meteorite impact rate on Mars, revealing that meteoroids of a basketballs size do a slam dunk on the planet almost daily.

The team has also managed to identify a new class of Mars quakes called Very High-Frequency (VF) events, triggered by these basketball-sized meteoroid strikes.

Starting their probe in December 2021, the experts found that Mars is subject to anywhere between 280 and 360 meteorite strikes each year. This creates impact craters that are over 8 meters in diameter.

To get to this conclusion, the team relied on seismic data collected from NASAs InSight Mission to Mars. It seems our Martian neighbor enjoys a game of cosmic basketball more often than we thought, five times more, to be precise.

To understand the inner structure of planets, we use seismology. This is because as seismic waves travel through or reflect off material in planets crust, mantle, and core, they change. By studying these changes, seismologists can determine what these layers are made of and how deep they are, said study co-first authorDr Natalia Wojcicka, research associate at Imperial College LondonsDepartment of Earth Science and Engineering.

On Earth, you can more easily understand the inner structure of our planet by looking at data from seismometers placed all around the globe. However, on Mars there has been only one SEIS. To better understand Mars inner structure, we need more seismometers distributed across the planet.

The initial estimates put the scale of meteorite impacts between two to 10 times higher than we previously expected, depending on the meteoroids size. This revelation comes courtesy of the research team at Brown University.

Its possible Mars is more geologically active than we thought, which holds implications for the age and evolution of the planets surface, said lead researcher Dr. Ingrid Daubar, a planetary scientist at Brown.

Our results are based on a small number of examples available to us, but the estimate of the current impact rate suggests the planet is getting hit much more frequently than we can see using imaging alone.

In the quest to unlock Mars secrets, the team leveraged InSights highly sensitive onboard seismometer to identify new impact craters from meteoroids, which remained hidden from the orbits view.

Consequently, we might need to revise the current Martian cratering models. Does that make Mars younger or older we might wonder?

The discovery of Mars and its meteorites could lead to a radical transformation in comprehending the Martian surface and the history of impacts other planets in our solar system have endured. This understanding is critical for predicting potential hazards that our future exploration missions to Mars could face.

The research team meticulously analyzed the seismic signals from InSight, cross-referencing them with the images taken by NASAs Mars Reconnaissance Orbiter. The result? Pinpoint precision on when and where these cosmic basketball games occurred on Mars.

Its possible that more events that InSight picked up during its mission were actually impacts, said Dr. Daubar. Next steps are to do more detailed orbital searches to try to confirm this using machine learning techniques. If we can confirm even more impacts, we might be able to find other seismic signals that were caused by impacts, too.

The research was a collaborative effort carried out by a dedicated team from several prestigious institutions. These include Brown University, Institut Suprieur de lAronautique et de lEspace, University of Oxford, Imperial College London, U.S. Geological Survey, ETH Zurich, University of Arizona, NASAs Jet Propulsion Laboratory, and Universit Paris Cit.

As we prepare for future missions to the Red Planet, we can confidently say with a little caution thrown in that the court is set for a cosmic game of basketball.

The study is published in the journals Science Advances and Nature Astronomy.

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Mars is hit by basketball-sized meteorites almost daily - Earth.com