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Mars rocks that were blasted off the surface of the Red Planet millions of years ago have been traced back to craters where they originated, which could transform our understanding of Mars’s volcanism and evolution

Researchers developed a novel reagent that enhances the precision of drug synthesis. This innovative method introduces a new sulfur fluoride exchange (SuFEx) reagent that allows for highly controlled production of crucial sulfur-based molecules, including sulfinamides, sulfonimidamides and sulfoximines.

There’s a link between Earth’s ocean salinity and its climate. Salinity can have a dramatic effect on the climate of any Earth-like planet orbiting a Sun-like star. But what about exoplanets around M-dwarfs?

Every planet has a measurable albedo, the percentage of starlight it reflects back into space. It’s measured on a scale from 0, which would be a black object that reflects no light, up to 1.00, an object that reflects all light. Since a higher albedo reflects more starlight, it has a cooling effect on an object’s climate. In our Solar System, Saturn’s moon Enceladus has the highest albedo. Enceladus is covered in bright, reflective ice that reflects most of the sunlight that reaches it. (Note that there are different measurements for albedo, and they can be quite different, leading to some confusion.)

Saturn’s moon, Enceladus, is covered in bright ice and is the most reflective object in the Solar System. Image Credit: NASA, ESA, JPL, SSI, Cassini Imaging Team

Mercury has the lowest albedo because it’s covered in mostly dark rock. (Objects like comets can have even lower albedos.)

Earth’s albedo is about 0.3, largely due to our planet’s cloudy atmosphere. The ice in Antarctica, Greenland and the seasonal pack ice in the Arctica also contribute. Earth’s albedo changes throughout the seasons as ice expands and recedes. In short, Earth’s albedo helps regulate the planet’s climate.

The ocean’s salinity levels affect how much sea ice forms and, in turn, affects Earth’s albedo. The more salt there is, the more the freezing point drops, making it harder for ice to form. Higher salinity means less ice, which means the albedo is lower and less sunlight is reflected back into space.

But how would ocean salinity affect exoplanets that orbit stars which are different from our Sun? That’s the question behind new research titled “Climatic Effects of Ocean Salinity on M Dwarf Exoplanets.” The lead author is Kyle Batra from the Department of Earth, Atmospheric, and Planetary Science at Purdue University. Batra is also a member of the NASA Network for Ocean Worlds Exo-oceanography Team.

M Dwarfs are also called red dwarfs, and their light is different from the Sun’s. Plenty of research has been done into ocean salinity and its overall effect on Earth’s climate. According to the authors, research is lacking when it comes to red dwarf exoplanets. “However, how ocean composition impacts climate under different conditions, such as around different types of stars or at different positions within the habitable zone, has not been investigated,” the authors write.

M dwarf exoplanets are particularly important when it comes to the study of exoplanets and their potential habitability. M dwarfs are low-mass stars that have extremely long, stable lifespans. That’s a benefit for potential habitability. M dwarfs are also the most plentiful type of star, so logic says they host the most rocky planets, and observations show us they host few gas giants.

The researchers worked with several key variables in their models, including how instellation changes over a star’s lifetime.

The researchers varied installation and salinity in their model and used the spectra from two well-known stars and two types of planetary oceans. Parameters not specified in this list are fixed at present-day Earth values. Image Credit: Batra et al. 2024

The researchers used an ocean-atmosphere general circulation model (GCM) to investigate how M dwarfs and G-type stars like our Sun respond to ocean salinity. The results show that stars like our Sun respond more dramatically to changes in ocean salinity. “We find that increasing ocean salinity from 20 to 100 g/kg in our model results in non-linear ice reduction and warming on G-star planets, sometimes causing abrupt transitions to different climate states,” they write.

Just as on the real Earth, the G-type star simulations showed that sea ice was restricted to high latitudes and that its coverage decreased as the salinity rose. Coverage went from 19.5% at 35 grams of salt per kg down to 3.5% at 100 grams per kg. That’s a sharp transition.

Transitions were less abrupt on M dwarfs. “Conversely, sea ice on M-dwarf planets responds more gradually and linearly to increasing salinity,” they write.

This figure from the research sums up the effect that ocean salinity has on sea ice. Image Credit: Batra et al. 2024

The researchers also determined how salinity and ice cover affected surface temperatures. On Earth, the average surface temperature rose from 8 Celsius to 14 C as salinity increased from 35 to 100 grams/kg. M-dwarf planets didn’t show a similar rise in surface temperature.

“Moreover, reductions in sea ice on M-dwarf planets are not accompanied by significant surface warming as on G-star planets,” they explain.

Planets in habitable zones around M-dwarfs share another characteristic. Since the habitable zone around an M-dwarf is so much closer to the star than around a Sun-like star, many of the planets are expected to be tidally locked. That affects everything about their climates.

“In this scenario, sea ice is even less coupled to planetary albedo than in our simulations with Earth-like rotation because the ice on the night side would not interact with incoming radiation,” the authors explain.

In a tidally locked scenario, oceanic and atmospheric mixing has more dynamic variables. “Under different rotation and circulation regimes, the climate sensitivity to salinity may, therefore, differ,” the researchers explain. They leave it to future research to investigate those scenarios.

These results are very interesting, but unfortunately, an opportunity to test them against observations won’t arise any time soon because we can’t remotely sense ocean salinity. In fact, we’re not even certain that what seem like exoplanets with oceans do, in fact, have oceans. But at least this work shows what effect ocean salinity can have on the plentiful rocky planets that orbit the galaxy’s M-dwarfs.

“This is an encouraging result that suggests uncertainties regarding exo-ocean salinity are less of a concern for understanding the climates and habitability of M-dwarf planets compared to G-star planets,” they conclude.

The post Ocean Salinity Affects Earth’s Climate. How About on Exoplanets? appeared first on Universe Today.

The asteroid that led to the extinction of the dinosaurs 66 million years ago probably came from the outer solar system.

Although I’m staying away from most of the news, i do follow the election news, and am aware of how Harris has befuddled Trump as Democrats, enthusiastic for a candidate who’s mediocre at best, have taken Harris above the Orange Man in the polls.

As always, I emphasize that I’m a never-Trumper, but I’m probably a not-Harriser, either, as I may vote for a third candidate, or not vote at all, since my state will go Democratic anyway. I also note that Harris is completely avoiding press conferences and interviews, since she’s not at all good on thinking on her feet or speaking intelligibly on the issues. I am baffled for the tremendous Democratic enthusiasm for Harris, but I guess I can understand it as it gives us a way to avoid Trump, who looked as if he was going to win.

But I argue that Harris, despite her promise, did not earn the nomination but simply inherited it, and I’m sad that the person likely to be chosen leader of our country is someone without the smarts and savvy of someone like Gretchen Whitmer, my previous favorite. (n.b. please do not tell me that I MUST vote as doing so won’t help the Democrats, and I will look askance at claims that Kamala Harris is the greatest thing since sliced bread.)

Now that I’ve gotten that off my chest, here are three items I’ve stolen from Nellie Bowles’s weekly news summary at The Free Press, called this week “TGIF: the RayGun goes off.”

→ Kamala is up big: Another week in which Kamala Harris does some high-energy rallies. . . and not much else. The Democratic nominee has so far given no interviews, no press conferences, and is just generally keeping it light on details like, say, how she plans to run the country. And it’s working. The voters are warming to Kamala—or at least the loosely reality-based version of Kamala Harris being put forward by a pliant press. According to The Cook Political Report, Harris now leads or ties Trump in all but one of the seven battleground states. The latest national Emerson poll puts Harris four points ahead on 50 percent to Trump’s 46 percent. Nate Silver’s magic election machine also has Harris ahead, as do the betting markets. Remember how a few months ago every expert and political insider insisted that an obviously over-the-hill Joe Biden was a better candidate than Harris? Or that Biden alone could beat Trump? Me neither.

I am but a passenger in the vibes election. And I am dangerously close to putting in a bet on Kamala.

I’d bet on her winning, at least at this stage of the election. But et’s wait until the candidates debate each other and give interviews and press conferences.

→ Oi, mate, be nice or else! I have some British colleagues and they’re all really nice. Polite, considerate, good manners, hard workers, never cry in public, only slightly concerning drinking habits. Anyway recent headlines out of Blighty have me wondering: Is that just because it’s actually illegal to be a dick over there? After some ugly anti-immigrant riots in the UK, in which real-life people tried to do real-life harm to other real-life people, the big takeaway from the powers that be is that people who are mean on the internet should be put in jail. “Think before you post,” warned prosecutors. Director of Public Prosecutions Stephen Parkinson told Brits: “You may be committing a crime if you repost, repeat or amplify a message which is false, threatening, or stirs up racial / religious hatred.” And one of Britain’s police chiefs even threatened to extradite U.S. citizens who break Britain’s censorship laws—to which the only reasonable response is a big, fat, American middle finger. I can think of no more just war than refighting the American War of Independence, only this time over busybody speech codes and our right to say crazy shit online rather than a tax on tea. Hand me my musket, and fire up Facebook. We’re taking no prisoners.

→ Goodbye, weird kid sports: The Algerian boxer Imane Khelif’s gold medal win highlighted how the IOC is rather squirrely about how they separate the sexes in sports. Is it by what’s listed on your passport? Your testosterone level? What’s coded into your DNA? Whether or not you’re good at math? Who knows! But let’s get real: The Olympics have been playing fast and loose with their standards for quite a while. Skateboarding, speed climbing, BMX racing, and—the newest, dumbest addition—breakdancing all featured as Olympic sports in Paris. I’m not saying these activities don’t require athletic prowess; I’m just saying if the uniform is cargo pants and a sideways hat then maybe it should be part of a different competition than the one Simone Biles participates in. This year, the Australian breakdancer Rachael Gunn, a.k.a. RayGun, participated in the competition, earning herself exactly zero points for her wild display on the break floor. She has a PhD in cultural studies and her thesis was on “Deterritorializing gender in Sydney’s breakdancing scene: A B-girl’s experience of B-boying,” and oh, it showed. After being roundly ridiculed online for her performance Gunn shared the quote, “Don’t be afraid to be different, go out there and represent yourself, you never know where that’s gonna take you.” But sometimes you know exactly where you’re going, like if you sign up for the Olympics as a breakdancer. I commend Raygun for participating and answering the question we all ask ourselves when we watch the Olympics, which is, “I wonder how I would stack up.” Now we know. Breakdancing, and the modern pentathlon that apparently involved laser pistols, will mercifully not be a part of L.A.’s 2028 program.

Okay, one more from Nellie (see also this link from reader Ginger K.):

→ I love my quaint hometown: A referendum in Pittsburgh that would cut all ties with Israel is moving through the legislative process. If it makes it to the ballot, voters will get to choose whether the city charter will be amended to bar “investment or allocation of public funds, including tax exemptions, to entities that conduct business operations with or in the state of Israel.” This is like BDS on crack. If it were to pass, the lights in the city would go out (since we couldn’t do business with Duquesne Light because they do business with Israel) and there would be no more Narcan, a drug manufactured by an Israeli company. Also: There would be no fuel for the city vehicles like patrol cars, nor any vehicles at all, since oil and gas companies and car companies do business with the Jewish state. This sounds like a really promising initiative that will make life in Pittsburgh—a key stakeholder in the war in Gaza—better for all. Also, shout-out to the brave highway blockers in L.A.! If they adopted the Pittsburgh measure, though, they could just take the ambulances away instead of blocking them.

.  .  . and that’s the way it is.

The dramatic dimming of a light source ~ 870 million light years away from Earth confirms the accuracy of a detailed model.

Today, many commercial tools claim to be highly successful at detecting machine-generated text, with up to 99% accuracy, but are these claims too good to be true? RAID, the Robust AI Detection benchmark, which shows that most detectors are easily fooled, setting a new bar for AI detection to clear.

A groundbreaking technology has been unveiled that improves the efficiency of thermoelectric materials, which are key in converting waste heat into electricity, by altering their geometry to resemble an hourglass. Unlike previous research that solely depended on the material properties of thermoelectric substances, this new approach is expected to have widespread applications in thermoelectric power generation.

A new study assessed the feasibility of recovering phosphorus from municipal wastewater as an alternative sustainable source of this non-renewable mineral.

Microscope images could be obtained much more quickly -- rather than one pixel at a time -- thanks to a new imaging method for neutral atomic beam microscopes. It could ultimately lead to engineers and scientists getting faster results when they are scanning samples.

Microscope images could be obtained much more quickly -- rather than one pixel at a time -- thanks to a new imaging method for neutral atomic beam microscopes. It could ultimately lead to engineers and scientists getting faster results when they are scanning samples.

New research using a decommissioned section of the beam pipe from the Large Hadron Collider (LHC) at CERN has bought scientists closer than ever before to test whether magnetic monopoles exist. Scientists have revealed the most stringent constraints yet on the existence of magnetic monopoles, pushing the boundaries of what is known about these elusive particles.

Researchers have found a better method to recycle polyurethane foam from items like mattresses: They are not only able to break down PUR and separate the two main components -- they can do it in one go. This is great news for the budding industry that aims to chemically recover the original components of the material -- making their products cheaper and better.

On May 11, a gorgeous aurora surprised stargazers across the southern United States. That same weekend, a tractor guided by GPS missed its mark. What do the visibility of the northern lights have in common with compromised farming equipment in the Midwest? A uniquely powerful geomagnetic storm, according to new research.

Society relies heavily on diverse fluidic technologies. The ability to precisely capture and release various chemical and biological fluids plays a fundamental role in many fields. A long-standing challenge is to design a platform that enables the switchable capture and release of liquids with precise spatial and temporal control and accurate volumes of the fluid. Recently, researchers have invented a new method to effectively overcome this challenge.

A zinc-air microbattery could enable the deployment of cell-sized, autonomous robots for drug delivery within in the human body, as well as other applications such as locating leaks in gas pipelines.

A zinc-air microbattery could enable the deployment of cell-sized, autonomous robots for drug delivery within in the human body, as well as other applications such as locating leaks in gas pipelines.

An experiment to test distant particles’ ability to correlate their behaviour is one of the strongest pieces of evidence that classical ideas about reality are incorrect

Well-placed observers have a rare opportunity to see an interplanetary spacecraft early next week.

If skies are clear, dedicated observers and imagers have a shot early next week at seeing a spacecraft headed to Jupiter.

The Mission is JUICE, the European Space Agency’s Jupiter Icy Moons Explorer. Launched atop an Ariane-5 rocket from Kourou Space Center in French Guiana on April 14th, 2023, JUICE is due to arrive at Jupiter in 2031. But first, the spacecraft will perform several planetary flybys to pick up speed, hurdling it towards the outer solar system.

Firsts for ESA

JUICE marks several firsts for space exploration and ESA. JUICE is the first non-NASA solo mission to the outer solar system, as well as the first ESA mission to Jupiter. The mission also follows in the footsteps of NASA’s Juno mission, utilizing enormous solar panels instead of a nuclear-powered MMRTG for power.

In another first, JUICE will perform the first-ever twin Earth-Moon flyby for this upcoming boost. This is a challenging ‘thread the needle,’ sort of maneuver, as the Moon flyby sets up the spacecraft for the Earth flyby. The maneuver is termed a ‘LEGA,’ or Lunar-Earth Gravitational Assist. JUICE fired its engines for 43 minutes last year to set it up for this month’s Earth-Moon flyby. A series of four smaller course correction burns were recently carried out, starting with a 31-second maneuver on July 22nd.

The big test for the spacecraft will come in 2031, when JUICE fires up its main engines for orbital insertion around Jupiter. The trick during any engine burn for the spacecraft is to not induce any unwanted wobbles in the enormous cruciform-shaped solar panels.

The double flyby is the fortuitous result of the launch window back in 2023. The first Moon flyby gives engineers a chance to tweak the Earth pass shortly before closest approach if needed. The total delta-V maximum for the spacecraft is 2,700 meters per second or 6,000 miles per hour.

JUICE was even briefly mistaken for an incoming Potentially Hazardous Asteroid early this month. The spacecraft poses no hazard to the Earth-Moon system.

The ATLAS sky survey nabs JUICE. Credit: ATLAS. Previewing the Flyby

Here are the specifics for the encounter:

The closest Moon approach occurs on Monday, August 19th at 21:16 Universal Time (UT), 700 kilometers from the lunar surface.

A diagram of the Moon encounter. Credit: ESA.

Closest Earth approach occurs about 24 hours later on Tuesday, August 20th at 21:57 UT. At its closest, JUICE will pass 6,807 kilometers from the surface of Earth over northeastern Asia and the Pacific. This encounter happens in the daytime. Australia and southeast Asia have the best shot at seeing JUICE inbound just before closest approach in the pre-dawn sky.

…and a diagram of the Earth encounter. Credit: ESA.

For Europe and North America, the circumstances are less favorable. These locales will see the spacecraft farther out when it’s highest in the sky. For example, Paris will see the spacecraft at around 23:20 UT at a range of 220,000 miles/354,000 kilometers out. Boston will see JUICE at a range of 150,000 miles/241,000 kilometers away around 6:20 UT in the predawn sky.

The JUICE mission from @esa returns to Earth this month for a gravitational assist from both the Moon & Earth. It’s destination is Jupiter, where it will study its moons and even orbit Ganymede before crashing into it. @ESA_JUICE pic.twitter.com/5C3OUkkJ0J

— Tony Dunn (@tony873004) August 4, 2024

The southeastern U.S. gets another shot around 1:00 UT on August 21st (9:00 PM Eastern Daylight Time August 20th). This low to the horizon opportunity occurs at dusk, as the spacecraft is then about 30,000 miles distant.

ESA’s ESOC (European Space Operations Centre) and the worldwide Estrack network will track JUICE throughout the flyby. This will also give mission controllers a chance to test key instruments, which will be switched on during the pass. Of special concern is the RIME (Radar for Icy Moons Exploration) instrument. RIME seems to be getting interference from other spacecraft instruments. Controllers will operate it in both solo and tandem mode along with other onboard instruments during the lunar flyby, in an effort to troubleshoot RIME. RIME is crucial to probing the interior of Jupiter’s icy moons.

Spotting JUICE

The key to spotting JUICE is knowing just where and when to look. JUICE is 27 meters across from the tip of one solar panel to another, and will pass Earth within range of the ring of geostationary satellites. A good specular glint of the Sun off of one of the large solar panels could temporarily raise JUICE in range of naked eye brightness.

Getting a precise position on JUICE is tricky, as most planetarium programs won’t include the deflection of the spacecraft due to the gravity of the Earth and the Moon. Generating ephemerides with JPL Horizons is your best bet, as it’ll give you a precise position in the sky in Right Ascension (RA) and Declination to point and conduct a search. Simply watch at the appointed time, and attempt to ‘ambush’ JUICE as it glides past. Much like a satellite, JUICE will look like a moving ‘star’ drifting across the field of fixed background stars.

JUICE is spacecraft ID -28 in the JPL Horizons System.

Astronomer Gianluca Masi caught sight of JUICE during a Virtual Telescope session on August 9th:

JUICE from August 9th, at 3.3 million kilometers out. Credit: Gianluca Masi/The Virtual Telescope Project.

Heavens-Above may post tracking maps for JUICE. They’ve done so in the past… we’ll note these here this weekend if they turn up.

Next up, JUICE will flyby Venus next August. It will then make two more Earth flybys, one in 2026 and a final one in 2029.

Good luck and clear skies, on your quest to nab JUICE on this historic Earth-Moon flyby.

The post See JUICE Next Week During Its Earth-Moon Flyby appeared first on Universe Today.

Russia's attacks and occupation of Ukraine's nuclear power plants have shocked observers, bringing a new and dangerous dimension to warfare. What should Ukraine do as it gains the chance to turn the tables?