Ancient ice beneath the surface of comet 67P is softer than candyfloss

 When the EU Space Agency’s Philae lander arrived on the comet 67P/Churyumov-Gerasimenko – also called comet 67P – it bounced twice before reaching its final resting place. Now researchers have found the placement of the second bounce, which exposed the strange ice beneath the comet’s surface.

The Philae lander was carried to 67P aboard the Rosetta orbiter, which launched in 2004 and fell upon the comet in 2014. When Philae was dropped to the surface, the harpoons designed to carry it in situ didn’t fire, therefore the lander bounced. the situation of the primary bounce and therefore the lander’s final resting place were both found, but we didn’t know where the second bounce materialized until now.

“I think it’s one in all the foremost positive things that happened on the mission, that it bounced because we managed to induce science from three locations on the comet,” says Laurence O’Rourke, a member of ESA’s Rosetta team. O’Rourke and his colleagues found the second bounce site by analyzing pictures from Rosetta taken before and after Philae’s landing.

They found a bright streak across a pair of boulders during a region that O’Rourke nicknamed “skull-top ridge” due to its resemblance to a skull in a number of the pictures. “It was sort of a chainsaw sliced through the ice,” he says. Philae appears to own bounced between the boulders, producing four slashes that exposed the primitive ice beneath the comet’s surface layer of dust.

Analyzing those gashes allowed the researchers to calculate the strength of the ice, which they found is weaker than candyfloss. “This ice that’s 4.5 billion years old is as soft because the foam that’s on top of your cappuccino, it’s as soft as sea foam on the beach, it’s softer than the softest snow after a snowstorm,” says O’Rourke.

Knowing that a number of the comet’s ice is so soft could help future landers find a safer place to touch down on 67P or other comets prefers it, he says. It could even be important for understanding a way to protect Earth should a comet ever head our way. “You cannot just hit it with an object and expect it to maneuver or disintegrate,” says O’Rourke. “It would be like punching a cloud.”

'Weird' Molecule Detected on Titan Has Never Been Found in Any Atmosphere

 Titan, the already pretty weird moon of Saturn, just got a touch bit weirder. Astronomers have detected Cyclopropenylidene (C3H2) in its atmosphere - a particularly rare carbon-based molecule that's so reactive, it can only exist on Earth in laboratory conditions.

In fact, it is so rare that it's never before been detected in an environment, within the system, or elsewhere. the sole another place it can remain stable is that the cold innocent of the part. But it's going to be a building block for more complex organic molecules that would someday cause life.

"We think about Titan as a real-life laboratory where we are able to see similar chemistry thereto of ancient Earth when life was control here," said astrobiologist Melissa Trainer of NASA's Goddard Space Flight Center, one in every one of the chief scientists set to research the moon within the upcoming Dragonfly mission launching in 2027.

"We'll be trying to find bigger molecules than C3H2, but we want to grasp what's happening within the atmosphere to know the chemical reactions that lead complex organic molecules to create and precipitate to the surface."

Cyclopropenylidene – which even NASA researchers describe as a "very weird little molecule" – doesn't tend to last long in atmospheric conditions, because it reacts very quickly and simply with other molecules, forming other compounds.

Once it does so, it's not Cyclopropenylidene. In the region, any gas or dust is typically very cold, and really diffuse, which suggests compounds aren't interacting much, and Cyclopropenylidene can lallygag around.

Titan is incredibly different from the part. It's a variety of soggy, with hydrocarbon lakes, hydrocarbon clouds, and a predominantly nitrogen atmosphere, with a small amount of methane. The atmosphere is fourfold thicker than Earth's atmosphere (which is additionally dominated by nitrogen). Under the surface, scientists think there is a huge ocean of saltwater.

In 2016, a team led by planetary scientist Conor Nixon of NASA's Goddard Space Flight Centre used the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile to probe the moon's atmosphere, searching for organic molecules.

It was within the tenuous upper atmosphere, high above the surface, where they detected an unknown chemical signature. By comparing it to a database of chemical profiles, the team identified the molecule as Cyclopropenylidene. It's likely that the thinness of the atmosphere at that altitude contributes to the molecule's survival, but why it appears on Titan and no other world may be a mystery.

"When I realized i used to be observing Cyclopropenylidene, my first thought was, 'Well, this can be really unexpected,'" Nixon said. "Titan is exclusive in our scheme. it's proved to be a treasure trove of recent molecules."

Cyclopropenylidene is of particular interest because it's what's called a hoop molecule; its three carbon atoms are linked together during a ring (well, a triangle, but the principle is that the same). Although Cyclopropenylidene itself isn't known to play a biological role, the nucleobases of DNA and RNA are supported by such molecular rings.

"The cyclic nature of the release this extra branch of chemistry that enables you to make these biologically important molecules," said astrobiologist Alexander Thelen of NASA's Goddard Space Flight Centre.

The smaller the molecule, the more potential it's - reactions involving smaller molecules with fewer bonds are expected to happen faster than reactions involving larger, more complicated molecules. which means reactions involving smaller molecules, purely through numbers, are expected to end in a more diverse range of outcomes.

Previously, benzene (C6H6) was thought to be the tiniest hydrocarbon ring molecule found in any atmosphere (including Titan's). Cyclopropenylidene has it beat.

Titan is already a hive of organic chemical activity. The nitrogen and methane split within the sunlight, triggering a cascade of chemical reactions. Whether those reactions could end in life could be a question scientists are dying to answer.

"We're trying to work out if Titan is habitable," said geologist Rosaly Lopes of NASA's reaction propulsion Laboratory. "So we wish to grasp what compounds from the atmosphere get to the surface, and then, whether that material can get through the ice crust to the ocean below because we predict the ocean is where the habitable conditions are."

Working out which compounds are present within the atmosphere could be an important step in this research process. Cyclopropenylidene could also be small, and strange, but this extremely rare molecule can be a key piece of the Titan chemistry puzzle. Now we just need to determine how it fits in.

Exercise May Inhibit Cancer by Fuelling The Immune System, Study in Mice Suggests

 Exercise might prevent some sorts of cancer from growing and spreading, and while scientists still aren't sure why that's, new research on mice offers a possible explanation.

After intense physical activity, elevated levels of certain metabolites, like lactate, maybe 'feeding' important immune cells in our blood. The results are mainly supported experiments with mice, but preliminary tests in male humans suggest an identical mechanism may be at play.

"Our research shows that exercise affects the assembly of several molecules and metabolites that activate cancer-fighting immune cells and thereby inhibit cancer growth," says Helene Rundqvist, a cancer researcher at the Karolinska Institutet in Sweden.

Past research has shown that exercise is linked to a rather lower risk of tumours within the bladder, breast, colon, kidney and stomach and that we have strong clinical evidence that physical movement can help some patients cope and recover. it would even extend their life.

Further research on animals has shown similar results, with regular exertion somehow reducing the expansion of malignant tumours.

Still, the underlying mechanism behind this relationship has remained elusive. The cancer-fighting benefits of exercise could have something to try and do with changes during a person's weight, their hormones, or their system.

The new research investigates the latter possibility. Dividing cancerous mice into two groups - one with access to a spinning machine, and another with no type of physical activity - researchers found that the mice that often exercised showed slower cancer growth and better rates of survival.

To achieve this, however, mice needed to be able to produce cytotoxic T-cells, which are the white blood cells specialised to attack cancer within the body. Without the flexibility to supply these important immune markers, physical activity was unable to suppress cancer growth to an identical extent.

On the opposite hand, when mice with cancer weren't exercising but instead got an injection of T-cells from exercising peers, their prospects generally improved.

"These results demonstrate that [cytotoxic T cells] are altered by exercise to enhance their effectiveness against tumours," the authors write. 

These changes appear to own something to try and do with lactate - a metabolite produced within the muscle during exercise, which later seeps into the blood.

In mice, metabolites linked to exercise increased by up to 8-fold following exercise. for sure, T-cells within the blood showed increased uptake of those products.

The results support the findings of a previous study by a number of identical authors, which discovered that lactate can help fuel T-cells within the blood, potentially increasing their "anti-tumour activity". 

In this case, when mice got daily, high-dosage injections of lactate alone, the animals showed a rise in T-cells within the tumour and a decrease in overall tumour growth, even without exercise.

"These findings indicate that lactate infusion mimics a number of the consequences of exercise, but that exercise has additional, integrative, components beyond merely increased levels of lactate," the authors write.

While the research to date has mainly been focused on animal models, the new study conducted a preliminary test among humans that offered somewhat similar results.

Taking blood samples from eight healthy men before and after a 30-minute cycle, the team noticed a rise in a number of the identical elevated metabolites they saw in exercising mice.

If the identified metabolites are increasing in humans like they are doing in mice, the team is hopeful that products of exercise like lactate may boost the system, making T-cells simpler at killing cancer in humans also, although more research is required to analyze this link in our own species.

"We hope these results may contribute to a deeper understanding of how our lifestyle impacts our system and inform the event of recent immunotherapies against cancer," says Rundqvist.

Although this is often an exciting development, like most things in cancer research, exercise should not be checked out as some reasonable solution.

For example, during a meta-analysis back in 2016, researchers found that among people who did the foremost physical activity within the study, their total cancer risk was reduced by 10 per cent compared to people who did the smallest amount.

If your risk of developing cancer is 40 per cent over a lifetime, however, that only changes your cancer chance from 40 per cent to 36 per cent – a big reduction, sure, but also slight overall.

Still, if exercise really can modify the ability of cytotoxic T-cells in humans, then mimicking its underlying effects could also be one in all the foremost promising routes for future cancer treatments. Now we just should determine how it works.

Even Vampire Bats Socially Distance Themselves When They Feel Sick

 Bats have long endured a foul reputation, even before COVID-19 emerged. These highly mobile creatures that sleep in clustered colonies are well-known reservoirs of viruses, including coronaviruses, that, as we have seen, can spill over into humans.

But these innocent animals are unfairly maligned. they're important pollinators and pest controllers. And when bats are feeling sick, new research shows they naturally display their own type of social distancing behaviours, the same as the measures we've had to adapt to slow the spread of COVID-19.

The study had scientists tagging a bunch of untamed vampire bats from a colony in Lamanai, Belize, and tracking their social encounters every few seconds over a pair of days. after they injected the bats with a substance that triggered their immune systems, the 'sick' bats clearly changed their behaviour and have become less social.

"In the wild, [we observed] vampire bats – which are highly social animals – keep their distance when they're sick or living with sick groupmates," said Simon Ripperger, a bat researcher from The Ohio State University.

"And it will be expected that they reduce the spread of disease as a result."

Previous work from this group of researchers had shown that, in captivity, sick bats sleep more, move less, spend less time grooming other bats, and make fewer social calls (which usually attract their mates). The researchers call this 'sickness behaviour'.

"We really wanted to determine whether these behavioural changes also occur during a natural setting where the bats are within their natural social and physical environment," Ripperger told ScienceAlert.

Collecting data on social interactions between bats would even be useful if researchers want to predict how sickness behaviour can reduce the spread of disease in these animals, the identical way social distancing does in humans.

So the researchers analysed data from a briefly captured group of 31 common vampire bats (Desmodus rotundus), which are native to the geographical area, from a colony roosting inside a hollow tree.

Sixteen randomly selected female bats were injected with a substance to activate their system, which made them feel sick for some hours but didn't cause any real disease. Another 15 bats got a trial of salty water as a placebo.

Before the 'sick' and healthy bats were returned to their roost, they also had tiny sensors, each weighing but a penny, glued to their furry little backs. 

"The sensors gave us the chance to automatically track the behaviour of a complete grouping, instead of focal sample individuals at a time, what one usually does during a lab setting," Ripperger said. "That was an excellent success."

The sensors used to track social interactions between bats. (Simon Ripperger)

The custom sensors, designed by Ripperger and his colleagues, work by broadcasting a symbol every 2 seconds that 'wakes up' any neighbouring sensors (attached to a bat) within 5 to 10 metres.

Every time this happened within the three days after the bats were captured and released, the sensors logged an encounter. From the strength and duration of the pairwise signal, the scientists could tell when two bats came into close contact with each other, and for the way long.

"We focused on three measures of the sick bats' behaviours: what number other bats they encountered, what quantity total time they spent with others, and the way well-connected they were to the full social network," said behavioural ecologist Gerald Carter from The Ohio State University.

The network analysis shows that 'sick' bats were indeed less connected to their healthy, social roost mates.

In the first six-hour window after treatment, a 'sick' bat had on the average four fewer encounters than an impact bat, and 'sick' bats spent less time (25 minutes less) interacting with each partner. 

As expected, 48 hours later, once the treatment had worn off and also the 'sick' bats were feeling better, they mostly resumed their normal social behaviours.

"It was amazing that the effect was so clearly visible," Ripperger told ScienceAlert.

"Even without a sophisticated statistical analysis you directly saw what's happening simply from gazing the social networks."

It should be noted that because the researchers didn't infect the vampire bats with a true virus or bacteria, they didn't measure the spread of an actual disease during a bat colony, which could influence bat behaviour in other ways.

"It is vital to recollect that changes in behaviour also depend upon the pathogen," Carter said. "Some real diseases might make interactions more likely, not less, or they could cause sick bats being avoided."

The study also only checked out a little group of bats within one roost.

Tracking how bats move and interact between colonies are a greater challenge, especially as scientists are just discovering the massive distances that bats travel – even thousands of kilometres every year – between roosts.

Special Type of DNA in Owl Eyes May Be a 'Lens' That Supercharges Night Vision

 Owls are one in every of the rare avian predators that catch their prey by night, and new research suggests that there is something special within the way the DNA molecules in their eyes are packaged, giving them a strong visual advantage within the dark.

Through the method of natural action, the new study proposes that the DNA within the retinal cells of owls may are put together in such how that it acts as a kind of lens or vision enhancer, improving eyesight during the night.

The unusual trait hasn't been seen in birds before, which hints that owls have gone it alone on this particular evolutionary path, a minimum of among birds. the bulk of birds are diurnal like we are – is most active within the day and sleeping it all off in the dark.

"In the ancestral branch of the owls, we found traces of positive selection within the evolution of genes functionally associated with seeing, especially to phototransduction, and to chromosome packaging," write the researchers in their paper.

The team checked out the genomes of 20 different bird species, including 11 owls, identifying where positive selection had occurred – where beneficial mutations had been kept over generations. for sure, lots of this is going on within the areas of sensory perception, which is why owls can hear and see so well.

But the team also discovered signs of accelerated evolution in 32 genes that were more of a surprise. These genes were linked to DNA packaging and chromosome condensation – as if the structure of the molecules inside the owl eyes had actually adapted themselves to be able to capture more light.

A similar change in DNA molecule arrangement in retina cells has been seen before in nocturnal primates, and computer models of their molecular structure have suggested they will channel light.

This isn't the sole evolutionary boost that owls have for peering through the gloom – they even have retinas packed with rod cells for better twilight vision, for instance – but it'd definitely help in catching prey after dark.

Although the researchers' claims remain hypothetical, it's an intriguing idea. The comparison of genomes also supports the concept that owls did indeed evolve from an ancestor that was diurnal - seeing because the largest changes observed in their genetics seem to be associated with enhancing night-hunting abilities.

While owls kept the sharp talons they share with day-hunting birds of prey, like eagles and falcons, the researchers found genes that differed from owls' ancestors, and one which may potentially enhance their excellent hearing, visual sense, and soft feathers for silent flight. If the study's findings are confirmed, even the DNA molecules seem to be boosting the wonderful sight capabilities of owls.

The authors caution their proposed roles for the different genes are only suggestions for the instant, particularly with respect to how photoreceptors in owl eyes actually function. Direct observations and analysis is also ready to build upon the findings outlined here and will tell us even more about how owls gained their evolutionary advantages.

"Our study suggests novel candidate genes whose role within the evolution of owls is further explored," write the researchers.

COVID-19 Can Make Patients' Immune Systems Attack Their Own Bodies, Study Shows

 Across the globe, immunologists who retooled their labs to hitch the fight against SARS-CoV-2 are furiously trying to clarify why some people get so sick while others recover unscathed. The pace is dizzying, but some clear trends have emerged.

One area of focus has been the assembly of antibodies – powerful proteins capable of disabling and killing invading pathogens like viruses. Of great concern has been the sporadic identification of so-called autoreactive antibodies that, rather than targeting disease-causing microbes, target the tissues of people full of severe cases of COVID-19.

Early studies implicated these autoantibodies in dangerous blood clots forming in patients admitted to medical aid. More recently, they need been linked to severe disease by inactivating critical components of viral immune defenses during a significant fraction of patients with severe disease.

As an immunologist within the Lowance Center for Human Immunology at Emory University, I've got been investigating the response accountable for producing antibodies in COVID-19. Under the direction of Dr. Ignacio Sanz, our group has previously investigated immune responses contributing to autoantibody production in autoimmune disorders like lupus, and more recently in severe cases in COVID-19.

However, while we were ready to characterize the response in COVID-19 patients as autoimmune like, we couldn't confirm the assembly of autoantibodies hidden within their antiviral responses.

Now we can.

In a newly released study awaiting peer-review, we describe the alarming finding that within the sickest patients with COVID-19, autoantibody production is common – a finding with a large potential impact on both acute patient care and infection recovery.

Severe infection is linked with autoantibody production

Autoantibodies are available "flavors" that are usually related to specific disease types. Patients with lupus, for instance, will often have antibodies that concentrate on their own DNA – the molecules that compose the human genome.

Patients with autoimmune disease arthritis are less likely to own those antibodies, but more likely to indicate positive tests for autoantibody – antibodies that focus on other antibodies.

In this study, the Lowance Center group analyzed the medical charts of 52 patients in medical aid who were diagnosed with COVID-19. None of them had a history of autoimmune disorders. However, they were tested during infection for autoantibodies found in a very style of disorders.

The results are stark. quite 1/2 the 52 patients tested positive for autoantibodies. In patients with the very best levels of C-reactive protein (a marker of inflammation) within the blood, over two-thirds displayed evidence that their system was producing antibodies attacking their own tissue.

While these findings raise concerns, there are things that our data don't reveal. Although patients with severe disease clearly display autoantibody responses, the information doesn't tell us to what extent these autoantibodies contribute to the foremost severe symptoms of COVID-19.

It may be that severe viral illness routinely ends up in the assembly of autoantibodies with little consequence; this might just be the primary time we're seeing it. We also do not know how long the autoantibodies last. Our data suggest that they're relatively stable over some weeks. But, we want follow-up studies to know if they're persisting routinely beyond infection recovery.

Importantly, we believe that the autoreactive responses we've got identified here are specific to the SARS-CoV-2 infection – there's no reason to believe that similar results would be expected through vaccination against the virus.

Understanding the role of autoantibodies in COVID-19

However, while it's possible that these autoantibodies are benign, or maybe helpful in an exceedingly yet-unidentified manner, it is also possible that they are not. Maybe these self-targeted antibody responses do indeed contribute to disease severity, helping explain the delayed onset of severe symptoms in some patients which will correlate with antibody production.

This could be a reason that treatment with dexamethasone, an immunosuppressant often accustomed quell "flare-ups" of autoimmune disorders, could be effective in treating patients with only the foremost severe disease. it's also possible that these responses aren't short-lived, outlasting the infection and contributing to ongoing symptoms now experienced by a growing number of "long-hauler" COVID-19 patients.

Most concerning, it's possible that these responses could self-perpetuate in some patients, leading to the emergence of recent, permanent autoimmune disorders.

My colleagues and that I sincerely hope that this is often not the case – rather, that the emergence of autoantibodies in these patients could be a red herring, a quirk of viral response in some patients that may resolve on its own.

But we'd like to try to better than hope – we want to ask the correct questions and determine the answers. Fortunately, this study also gives us the tools to try and do that.

Autoreactive antibody test may reveal better treatments

The tests that were run on these patients to work out their "autoreactive profile" don't seem to be specialized. they're available to most hospital labs across the country.

Indeed, the 2 most typical antibodies that we discover in these patients, antinuclear antibodies and autoantibody, are detected by common tests utilized by rheumatologists.

Our study shows that by testing for just these two autoantibodies, and also the inflammatory marker CRP, we could also be ready to identify patients more likely to be experiencing potentially dangerous immune responses which may take pleasure in more aggressive immune modulation.

Further, autoreactivity testing might help identify patients who might enjoy rheumatological follow-up to observe recovery and help us understand whether some cases of "long-hauler" COVID-19 could be associated with persisting autoantibodies. If so, these patients might reply to the identical immune-targeted therapies that are successful in MIS-C where autoantibody production has now been documented.

Finally, by testing patients immediately following COVID-19 recovery, we will establish baselines and start to trace the possible emergence of the latest cases of autoimmunity following this terrible disease, and plan early rheumatological intervention if needed.

We now have the tools. it is time to begin using them. The Conversation

Matthew Woodruff, Instructor, Lowance Center for Human Immunology, Emory University.

Scientists Just Reported The First Unambiguous Detection of Water on The Moon

 It's official. There's water on the Moon.

We've thought that there was for over a decade, supported detections described back in 2009, but there was room for interpretation within the wavelengths used. Now, employing a different wavelength unique to water, scientists report the primary unambiguous detection.

Those 2009 conclusions were apparently on the money.

The ambiguity arose because the 2009 detections were made within the 3-micrometre infrared band. At this wavelength, there have been two possibilities - water, or another hydroxyl compound comprising hydrogen and oxygen.

Led by astronomer Casey Honniball of the NASA Goddard Space Flight Centre, a team of scientists decided to appear into the wavelength that would confirm or overturn those findings. The 6-micrometre infrared band should show a line which will only be created by two hydrogen atoms and one oxygen atom - what's called the H-O-H bend vibration.

But actually making an unambiguous detection in this band is difficult. It requires the employment of the Stratospheric Observatory for Infrared Astronomy (SOFIA), a special, one-of-a-kind telescope that's flown during a plane above the majority of Earth's atmosphere.

"SOFIA is that the only current and planned observatory capable of those observations," Hannibal told ScienceAlert.

"Current lunar spacecraft don't have instruments which will measure at 6 micrometres, and from the bottom, Earth's atmosphere blocks 6-micron light, so it can't be done from ground-based observatories. SOFIA flies above 99.9 per cent of the Earth's water vapour, which allows 6-micrometre light to withstand and be observed. and fortuitously SOFIA's FORCAST instrument can make 6-micrometre measurements and appearance at the Moon."

Using FORCAST, the team carefully studied a vicinity during which the 3-micrometre detections had been made - high southern latitudes, around the pole. There, they found the emission line they'd been hoping for - that unique signature that would only be created by the H-O-H bend vibration.

Based on their detections, the team estimates water abundances of around 100 to 400 parts per million - in keeping with 3-micrometre detections made by the Moon Mineralogy Mapper.

Of course, there aren't any liquid lakes sloshing around on the lunar surface, and any frozen water would sublimate as soon because the sunlight hit it. But there are multiple ways the Moon could still be harbouring surface water.

"We mainly think the water is in glass," Hannibal said.

"When a micrometeorite impacts the Moon, it melts some lunar material, which quickly cools and forms a glass. If there's water already present, formed during or delivered during the impact, a number of the water will be captured within the structure of the glass while it cooled."

In a separate paper led by astronomer Paul Hayne of the University of Colorado Boulder, scientists explored another possibility - regions of permanent shadow in polar craters. At high latitudes, high crater rims create regions that sunlight never touches.

In these spots, temperatures never reach above approximately -163 degrees Celsius (-260 degrees Fahrenheit), creating cold traps that would harbour hidden patches of water ice.

Using data from NASA's Lunar Reconnaissance Orbiter, Hayne and his colleagues calculated that there can be the maximum amount as 40,000 square kilometres (15,000 square miles) of such permanently shadowed surface. And 60 per cent of that's at the South Pole.

"The temperatures are so low in cold traps that ice would behave sort of a rock," Hayne said. "If water gets in there, it is not going anywhere for a billion years."

Both papers have important implications for future lunar missions. NASA is getting to establish a lunar base as a part of the Artemis mission; if an abundant source of water is often found nearby, lunar residents could make use of it for drinking, for growing crops, even splitting it using electrolysis to get hydrogen for burster.

But we'd like to induce an improved picture of where the water may well be, and the way much is there. The work of Haynes' team will help see where to look; the work of Honniball's team gives us the how. All we want now could be the telescope time.

"We are granted two more hours on SOFIA and are requesting a further 72 hours," Hannibal said. "With more observations, we are going to be ready to characterise the behaviour of water across the lunar surface and understand its source, where it resides, and if it moves around the lunar surface."