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How A New Mission To Phobos Could Rewrite The History Of Mars – Forbes

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When it comes to the worlds beyond Earth in our Solar System, it’s only natural to wonder whether our planet was alone in being home to native life. The fourth planet from the Sun, Mars, is a particularly interesting candidate, as there’s overwhelming evidence that its surface once possessed large amounts of liquid water, pooling in lakes, rivers, and even oceans. Long ago, we have every reason to suspect it had a thick atmosphere, temperate conditions, and even a third, inner, massive moon that dwarfed the other two — Phobos and Deimos — before falling back to Mars.

While Mars itself is vast, and any life that was once present has likely been extinct for billions of years, there’s a simple place to go to look for evidence of ancient processes that are easy to access: its innermost moon, Phobos. If we could gather material from the Phobian regiolith and bring it back here to Earth, we could analyze it and either confirm or challenge our best-supported ideas for the geological and chemical history of the red planet, and perhaps even find evidence for ancient life there. This isn’t a pipe dream, nor is it science fiction, but an actual mission approved and planned for launch in 2024: Martian Moons eXploration (MMX).

Upon its return to Earth in July of 2029, we’ll be able to analyze its samples, determining whether Mars was once home to life, whether Phobos was the result of a Martian impact or asteroid capture, and either confirming or rejecting a whole slew of hypotheses concerning Mars’s history. Here’s what we all should know.

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If we rewind the clock all the way back to the first ~1 billion years of the Solar System, the inner planets likely would have looked very different to the way they appear today, some 4.6 billion years after our formation. Earth, although life was already present in its oceans, had an atmosphere that was rich in molecules like methane and ammonia, with very small amounts of oxygen: produced as the waste product of anaerobic lifeforms. Venus and Mars, meanwhile, may have both been similarly hospitable to life early on, as they were anticipated to have atmospheres similar in thickness and composition to Earth’s, with copious amounts of liquid water on the surface and the same raw ingredients — precursor molecules to life — that were present in large quantities on Earth.

While Venus and Mars are suspected to have had divergent histories from both Earth and one another, their early environments may have been extremely similar to Earth’s. As such, they may have possessed simple lifeforms in their early days just as Earth did. If we can investigate them in sufficient detail, we just might find the critical evidence that reveals that life may not have been unique to Earth, even within our own Solar System. While it might make sense to probe the planets themselves for such evidence, the billions of years that have subsequently passed may make such signals difficult to unambiguously extract. That’s where the potential of Mars’s innermost moon, Phobos, comes into play.

The Solar System isn’t a well-siloed environment, where “what happens on a planet stays on that planet.” Instead, it’s an active, dynamical place, where asteroids, centaurs, and comets routinely cross the orbits of the planets and moons. While gravitational interactions frequently occur, perturbing orbits, causing energy exchange, and leading to the ejection or capture of various bodies, there’s also a non-trivial possibility of having a collision between one of these fast-moving, low-mass bodies and a planet or moon. When such an impact event occurs, it not only creates a crater on the world and covers it in debris, but can also kick fragments of the world it impacts out into space.

Every rocky planet and moon in the Solar System that we’ve investigated up close and doesn’t rapidly refresh its surface — either through volcanic activity, like Jupiter’s moon Io, or through the turnover of ices and liquids, like Saturn’s Enceladus or Neptune’s Triton — shows copious evidence for both recent and ancient cratering. Mercury, Mars, the Moon, and Ganymede are covered in a rich array of craters of varying ages, and it’s known that these impacts can send debris from one region of the Solar System to elsewhere: in that planet’s orbit and beyond. In fact, of all the meteorites that have been recovered here on Earth, approximately 3% of them have been determined to be of Martian origin.

If impacts on Mars can routinely send Martian debris all the way to planet Earth, it would be an absurdity for the particulate debris from those impacts to not extend above the Martian atmosphere, where it would collide with and stick to the Martian moons: Phobos and Deimos. Throughout the history of Mars, collisions with Mars-crossing asteroids and comets should have produced copious amounts of impact events, delivering a substantial fraction of the ejected material to its moons. Being closer to Mars than outermost Deimos, Phobos is expected to have accrued more than 1 million tons of Martian material, now mixed into its regiolith.

Based on numerical simulations, the fraction of Martian material mixed into Phobos’s outermost layers should exceed ~1-part-in-1000, making this an excellent place to look for “dead biosignatures” of Martian origin. The researchers searching for such extinct clues to past life on Mars have named it SHIGAI, for Sterilized and Harshly Irradiated Genes and Ancient Imprints, which also means “dead remains” in Japanese. Despite the harsh environment of space and exposure to billions of years of solar wind and radiation, these remains should persist. By sampling and returning the cocktail of material collected from Phobos’s regiolith, scientists will be able to analyze material originating from different eras and different locations across the surface of Mars.

The MMX mission, developed by the Japanese Aerospace Exploration Agency (JAXA), has already been in the planning and development stages since its announcement in 2015. The plan is for it to softly land on Phobos at least once (and possibly twice, to get two different sample locations), to collect samples using a pneumatic system. Once a sufficiently large set of samples have been taken, it will take off once again, flying-by Deimos numerous times, observing it and Mars, and then sending the sample-containing Return Module back to Earth for analysis. The Return Module itself is expected to arrive on Earth in July of 2029.

If this sounds ambitious, that’s because it is. Only a very small set of missions have ever accomplished the joint feats of:

  • traveling from Earth to another body in the Solar System,
  • making a soft, controlled landing there,
  • collecting samples from the object it landed on,
  • successfully taking off once again,
  • completing the journey back to Earth,
  • and surviving atmospheric re-entry,
  • so that the collected samples can be recovered an analyzed.

JAXA has been the world leader in endeavors such as this, with the Hayabusa and Hayabusa2 missions successfully returning samples from asteroids Itokawa and Ryugu: the first two sample return missions to be conducted since NASA’s Apollo program. While material is expected to be returned from Mars to Earth via the Mars Sample Return mission, the MMX mission should return the material collected from Phobos even earlier, providing the first return of Martian material, including the remains of possible organics, to Earth.

Depending on what arrives upon MMX’s return to Earth, we could uncover a view of Phobos that aligns with our current theories about its formation and history. Alternatively, we could receive a tremendous set of surprises that, quite literally, rewrites what we know about the history of Mars and the Martian planetary system. For example, like the other rocky planets present in our Solar System, we fully anticipate that Mars was born without moons of any type. After surviving the earliest phases of planet-formation in our youth, a major impact was suspected to occur, kicking up a large amount of debris that coalesced into three moons: a large, massive, innermost moon, with much-smaller Phobos orbiting exterior to that and Deimos comprising the final, outermost satellite.

Eventually, owing to both tidal forces and atmospheric drag, the innermost moon was disrupted and fell back to Mars, where it very likely created the large, asymmetric basin that accounts for the severe differences between the two hemispheres of Mars, as well as kicking up a tremendous amount of debris that could land on both Phobos and Deimos. If the material returned to Earth from Phobos matches up extraordinarily well with the material we’ve sampled and analyzed on the Martian surface — as determined by orbiters, landers, and rovers — the MMX mission could serve as a spectacular confirmation of this picture, strongly supported by simulations and the current evidence at hand.

However, it’s possible that the full suite of evidence is conspiring, at present, to mislead us about the origins of Phobos and Deimos. Perhaps there wasn’t a large, ancient impact on Mars that led to the origins of its moons; perhaps, instead, Phobos and Deimos are more like Saturn’s “oddball” moon Phoebe: a captured object, such as an asteroid, originating from elsewhere in the Solar System. While the orbits of Phobos and Deimos are extremely consistent with an origin from an ancient impact, their compositions and appearances appear to be quite asteroid-like. A sample return mission would reveal whether the composition of Phobos matches that of Mars or of the known types of asteroids.

It’s also possible that, despite its watery past and life-friendly early conditions, that life may not have ever arisen on the red planet. The evidence we have strongly indicates that over the first ~1+ billion years of the Solar System’s history, Mars possessed a thick atmosphere with large amounts of liquid water, and then transitioned — likely because of the death of its core’s magnetic dynamo — to become a low-pressure world where liquid water on its surface was impossible. The chemical imprints of such a scenario should appear frozen-in to the regiolith of Phobos if it occurred; if not, Phobos might reveal an alternative history, even one that’s entirely unexpected.

It might seem that sampling Mars, directly, is a far superior approach to sampling Phobos, but that’s not entirely true. As we can clearly see from orbiters, landers, and rovers, different locations on Mars have not only experienced substantially different histories, but leave different chemical fingerprints even today. The seasonal methane “burps” that we see coming from the ground don’t occur everywhere, but rather are limited in location and duration. Whenever we sample Mars directly and return its contents to Earth, we’re limited to whatever biomarkers — modern and ancient — are present at that specific location. If there’s life on Mars, but simply not in the location we’re sampling, we’ll miss it.

On the other hand, because impacts on Mars have occurred all over its surface and all throughout its history, the material of Martian origin that’s been deposited on Phobos means that the Phobian environment should truly provide a random sample of Mars. All possible Martian materials, from sedimentary to igneous rocks, covering all of Mars’s geological areas, should be present in some sort of quantity on Phobos. At the very least, the regiolith of Phobos should have significant contributions from several different regions and epochs on Mars. By collecting material from it and returning to Earth, we should get a random sample that provides insight into the planet-wide history of biological and chemical remnants on Mars, shedding light on any ancient life that may have existed there at one point.

There’s one more point that makes a sample return mission to Phobos so exciting: the comparably low degree of difficulty when compared to a sample return mission from Mars. First off, just like asteroids Itokawa and Ryugu, Mars’s moon Phobos is low enough in mass that it’s certainly covered in loosely-held rock, rubble, and dust, meaning that the instruments should have little difficulty in collecting the necessary material for a sample return. Second, the lack of any atmosphere and the extremely low surface gravity of Phobos should make gravitational escape extremely easy, compared to the difficulty of returning a sample from a world like Mars. Comparatively, a full-scale launch and return from the Martian surface — something never before attempted — is an exciting but risky proposition.

And finally, this would be the third attempt at an uncrewed sample return mission from a small-mass, airless body. It’s being performed by the same agency, JAXA, that has made the only two previous attempts: Hayabusa and Hayabusa2, both of which were successful. Ideally, both a Mars Sample Return mission and MMX, bringing back material from Phobos, will both be successful. But if you had to bet on only one, MMX has far fewer obstacles, and far fewer incidences of engineering problems that have never been reckoned with before, than a direct-from-Mars sample return.

It remains a fascinating and open question — perhaps the most interesting question we can ask about life beyond Earth in the Solar System — whether life ever existed on Mars. Although it’s a highly speculative proposition, it’s one that we have the potential to answer: not just down the road, but in the very near future. The combination of orbiters, landers, and rovers we have, both today and upcoming in the near-future mission timeline, will shed light on the presence and concentration of various biomarkers in the atmosphere, on Mars’s surface, and just beneath its surface. If the seasonal methane has a biological origin rather than a geochemical one, we should be able to know within a single decade.

When you fold in the upcoming sample return missions, from both Jezero Crater on Mars and from the surface of Phobos, we should become sensitive not only to the possibility of extant life on Mars, but of even ancient, now-extinct life. If life exists there now, these missions could teach us how such life first emerged and, later, evolved. If Mars was always devoid of life, these missions will provide valuable information in revealing why Mars is lifeless while Earth has always teemed with it. As always, the most important lesson is this: if we want to know what’s out there, the only way to find out is to look. With the Martian Moons eXplorer mission, the answers might be in our hands before the decade comes to a close.

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The total solar eclipse in North America could shed light on a persistent puzzle about the sun – Phys.org

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The total solar eclipse in North America could shed light on a persistent puzzle about the sun

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The path of eclipse totality passes through Mexico, the US and Canada. Credit: NASA’s Scientific Visualization Studio

A total solar eclipse takes place on April 8 across North America. These events occur when the moon passes between the sun and Earth, completely blocking the sun’s face. This plunges observers into a darkness similar to dawn or dusk.

During the upcoming eclipse, the path of totality, where observers experience the darkest part of the moon’s shadow (the umbra), crosses Mexico, arcing north-east through Texas, the Midwest and briefly entering Canada before ending in Maine.

Total solar eclipses occur roughly every 18 months at some location on Earth. The last that crossed the US took place on August 21 2017.

An international team of scientists, led by Aberystwyth University, will be conducting experiments from near Dallas, at a location in the path of totality. The team consists of Ph.D. students and researchers from Aberystwyth University, Nasa Goddard Space Flight Center in Maryland, and Caltech (California Institute of Technology) in Pasadena.

There is valuable science to be done during eclipses that is comparable to or better than what we can achieve via space-based missions. Our experiments may also shed light on a longstanding puzzle about the outermost part of the sun’s atmosphere—its corona.

The sun’s intense light is blocked by the moon during a total solar eclipse. This means that we can observe the sun’s faint corona with incredible clarity, from distances very close to the sun, out to several solar radii. One radius is the distance equivalent to half the sun’s diameter, about 696,000km (432,000 miles).

Measuring the corona is extremely difficult without an eclipse. It requires a special telescope called a coronagraph that is designed to block out direct light from the sun. This allows fainter light from the corona to be resolved. The clarity of eclipse measurements surpasses even coronagraphs based in space.

We can also observe the corona on a relatively small budget, compared to, for example, spacecraft missions. A persistent puzzle about the corona is the observation that it is much hotter than the photosphere (the visible surface of the sun). As we move away from a hot object, the surrounding temperature should decrease, not increase. How the corona is heated to such high temperatures is one question we will investigate.

We have two main scientific instruments. The first of these is Cip (coronal imaging polarimeter). Cip is also the Welsh word for “glance,” or “quick look.” The instrument takes images of the sun’s corona with a polariser.

The light we want to measure from the corona is highly polarized, which means it is made up of waves that vibrate in a single geometric plane. A polarizer is a filter that lets light with a particular polarization pass through it, while blocking light with other polarizations.

The Cip images will allow us to measure fundamental properties of the corona, such as its density. It will also shed light on phenomena such as the solar wind. This is a stream of sub-atomic particles in the form of plasma—superheated matter—flowing continuously outward from the sun. Cip could help us identify sources in the sun’s atmosphere for certain solar wind streams.

Direct measurements of the magnetic field in the sun’s atmosphere are difficult. But the eclipse data should allow us to study its fine-scale structure and trace the field’s direction. We’ll be able to see how far magnetic structures called large “closed” magnetic loops extend from the sun. This in turn will give us information about large-scale magnetic conditions in the corona.

The second instrument is Chils (coronal high-resolution line spectrometer). It collects high-resolution spectra, where light is separated into its component colors. Here, we are looking for a particular spectral signature of iron emitted from the corona.

It comprises three , where light is emitted or absorbed in a narrow frequency range. These are each generated at a different range of temperatures (in the millions of degrees), so their relative brightness tells us about the coronal temperature in different regions.

Mapping the ‘s temperature informs advanced, computer-based models of its behavior. These models must include mechanisms for how the coronal plasma is heated to such high temperatures. Such mechanisms might include the conversion of magnetic waves to thermal plasma energy, for example. If we show that some regions are hotter than others, this can be replicated in models.

This year’s eclipse also occurs during a time of heightened solar activity, so we could observe a coronal mass ejection (CME). These are huge clouds of magnetized plasma that are ejected from the sun’s atmosphere into space. They can affect infrastructure near Earth, causing problems for vital satellites.

Many aspects of CMEs are poorly understood, including their early evolution near the sun. Spectral information on CMEs will allow us to gain information on their thermodynamics, and their velocity and expansion near the sun.

Our eclipse instruments have recently been proposed for a space mission called moon-enabled solar occultation mission (Mesom). The plan is to orbit the moon to gain more frequent and extended eclipse observations. It is being planned as a UK Space Agency mission involving several countries, but led by University College London, the University of Surrey and Aberystwyth University.

We will also have an advanced commercial 360-degree camera to collect video of the April 8 eclipse and the observing site. The video is valuable for public outreach events, where we highlight the work we do, and helps to generate public interest in our local star, the sun.

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How the 2024 total solar eclipse is different than the 2017 eclipse



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Mar 30: An Australian Atlantis and other lost landscapes, and more… – CBC.ca

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Quirks and Quarks54:00An Australian Atlantis and other lost landscapes, and more…


On this week’s episode of Quirks & Quarks with Bob McDonald: 

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Archaeologists identify a medieval war-horse graveyard near Buckingham Palace 

Quirks and Quarks9:04Archaeologists identify a medieval war-horse graveyard near Buckingham Palace

We know knights in shining armour rode powerful horses, but remains of those horses are rare. Now, researchers studying equine remains from a site near Buckingham Palace have built a case, based on evidence from their bones, that these animals were likely used in jousting tournaments and battle. Archaeologist Katherine Kanne says the bone analysis also revealed a complex, continent-crossing medieval horse trading network that supplied the British elite with sturdy stallions. This paper was published in Science Advances.

University of Exeter researchers analyzed horse skeletons found near Buckingham Palace and conducted isotope tests on teeth to find out more about the animals’ origins. (University of Exeter)

In an ice-free Arctic, polar bears are dining on duck eggs — and gulls are taking advantage

Quirks and Quarks9:22In an ice-free Arctic, Polar bears are dining on duck eggs — and gulls are taking advantage

Researchers using drones to study ground-nesting birds in the Arctic have observed entire colonies being devastated by marauding polar bears that would normally be out on the ice hunting seals, except the ice isn’t there. What’s more, now they’re enabling a second predator — hungry gulls that raid the nests in the bears’ wake. Andrew Barnas made the observations of this “gull tornado” by following around polar bears in East Bay Island in Nunavut. The research was published in the journal Ecology and Evolution.

Aerial video of a polar bear on grassy, rocky terrain with white birds circling nearby.
A polar bear storms eider duck nests on East Bay island in Nunavut, while herring gulls follow closely behind to snack on any remaining eggs. (Submitted by Andrew Barnas)

A NASA mission might have the tools to detect life on Europa from space

Quirks and Quarks8:05A NASA mission might have the tools to detect life on Europa from space

NASA’s Europa Clipper mission, due to launch this fall, is set to explore the jewel of our solar system: Jupiter’s moon, Europa. The mission’s focus is to determine if the icy moon, thought to harbour an ocean with more water than all of the water on Earth, is amenable to life. However, postdoctoral researcher Fabian Klenner, now at the University of Washington, demonstrated how the spacecraft may be able to detect fragments of bacterial life in a single grain of ice ejected from the surface of the moon. The study was published in the journal Science Advances.

The silhouette of the spacecraft is flying over a brightly pink, blue and orange tinted moon with lots of darker coloured veins underneath with a slightly eclipsed Jupiter looming in the backdrop.
Scientists think under Europa’s icy shell, there is a global, saltwater ocean with twice the volume of Earth’s oceans combined. (NASA/Jet Propulsion Laboratory/Caltech)

Pollution is preventing pollinators from recognizing floral plants by scent

Quirks and Quarks7:50Pollution is preventing pollinators from finding plants by scent

Our polluted air is transforming floral scents so pollinators that spread their pollen can no longer recognize them. In a new study in the journal Science, researchers found that a certain compound in air pollution reacts with the flower’s scent molecules so pollinators — like the hummingbird hawk-moths that pollinate at night — fail to recognize them. Jeremy Chan, a postdoctoral researcher at the University of Naples, said the change in scent made the flowers smell “less fruity and less fresh.”

A huge insect that looks like a hummingbird hovers over a vibrant pink flower with its long antenna inside one of the blooms.
Scientists found that a hummingbird hawk-moth’s ability to recognize the smell of flowers is hampered by air pollution. (Thomas Kienzle/AFP/Getty Images)

An Australian Atlantis and underwater archeological remains in the Baltic 

Quirks and Quarks17:14An Australian Atlantis and underwater archeological remains in the Baltic

During the last ice age, sea levels were more than 100 metres lower than they are today, which means vast tracts of what are currently coastal seafloor were dry land back then. Geologists and archaeologists are searching for these lost landscapes to identify places prehistoric humans might have occupied. These included a country-sized area of Australia that could have been home to half a million people. Archaeologist Kasih Norman and her colleagues published their study of this now-drowned landscape in Quaternary Science Reviews

Another example is an undersea wall off the coast of Northern Germany that preserves an underwater reindeer hunting ground, described in research led by Jacob Geersen, published in the journal PNAS.

a black-and-white depiction of a small group of caribou walking between a low stone wall and an ocean coastline.
An artist’s representation of caribou being directed by a hunters’ stone wall, as it would have appeared 8-11,000 years ago, before rising sea levels left it 20m below the surface of the Baltic Sea. (Michał Grabowski)

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Solar eclipse April 8 – South Grey News

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March 28, 2024

Graphic: Appalachian Mtn Club

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Grey Bruce Public Health is urging residents to resist the temptation to look directly at the sun during the upcoming solar eclipse and take steps to safeguard their visual health during this relatively rare celestial event.

On April 8, 2024, parts of southern and eastern Ontario will experience a total solar eclipse for the first time since 1925. Grey-Bruce will be outside of the so-called Path of Totality — a narrow area where the moon will completely block out the sun — but will still experience a partial eclipse.

The eclipse is expected to begin at about 2 pm and continue until 4:30 pm The eclipse will peak around 3:20 pm.

It is never safe to stare directly at the sun, but it may be tempting to do so during a solar eclipse.

Looking directly at the sun during an eclipse can cause retinal burns, blurred vision, and/or temporary or permanent loss of visual function, according to the Ontario Association of Optometrists. Damage to the eyes can occur without any sensation of pain.

Grey Bruce Public Health advises the following:

  • Do not look directly at the sun without proper eye protection during the solar eclipse. Looking at even a small sliver of the sun before or after the eclipse without proper eye protection can harm vision.
  • Keep a close eye on children and other vulnerable family members during the eclipse to ensure they do not inadvertently look up at the sun without proper eye protection.
  • To safely view the eclipse, ISO-certified eclipse glasses that meet the ISO 12312-2 international safety standard must be worn. Ensure these glasses are in good condition, without any wrinkles or scratches, and that they fully cover the entire field of vision. Put on the glasses when looking away from the sun, then look at the eclipse. Look away from the sun before taking the glasses off.
  • Regular sunglasses or homemade filters will not protect the eyes.
  • It is not safe to view the eclipse through a camera/phone lens, telescope, binoculars, or any other optical device.

Other ways to safely experience the solar eclipse include watching a livestream of the event or creating and using an eclipse box or pinhole projector.

Anyone experiencing temporary vision loss or blurred vision during or after the eclipse should speak with their eye care professional or healthcare provider as soon as possible.

Anyone experiencing blindness (immediate or delayed) after viewing the eclipse must seek emergency care immediately.

More information on the upcoming eclipse is available on the GBPH website.


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South Grey News does not have the resources of a big corporation. We are a small, locally owned-and-operated organization. Research, analysis and physical attendance at public meetings and community events requires considerable effort. But contributions from readers and advertisers, however big or small, go a long way to helping us deliver positive, open and honest journalism for this community.

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