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The dynamics of how plants and animals change Earth is central to this last book in a trilogy by Other Minds author and "scuba-diving philosopher" Peter Godfrey-Smith

As the International Space Station comes to the end of its life, we should recognise its biggest achievement – showing that a better world is possible

Today’s Jesus and Mo strip, called “purpose,” once again deals  with the holy books, but this time Mo’s Qur’an. The Bible doesn’t have anything like the first verse; Jesus may have died a virgin, like his mother.

Here is one translation of the surah and verse at hand (33:40); note that Mo gets special connubial privileges:

O Prophet! We have made lawful for you your wives to whom you have paid their ˹full˺ dowries as well as those ˹bondwomen˺ in your possession, whom Allah has granted you. And ˹you are allowed to marry˺ the daughters of your paternal uncles and aunts, and the daughters of your maternal uncles and aunts, who have emigrated like you. Also ˹allowed for marriage is˺ a believing woman who offers herself to the Prophet ˹without dowry˺ if he is interested in marrying her—˹this is˺ exclusively for you, not for the rest of the believers. We know well what ˹rulings˺ We have ordained for the believers in relation to their wives and those ˹bondwomen˺ in their possession. As such, there would be no blame on you. And Allah is All-Forgiving, Most Merciful.

And the second (33:36):

It is not for a believing man or woman—when Allah and His Messenger decree a matter—to have any other choice in that matter. Indeed, whoever disobeys Allah and His Messenger has clearly gone ˹far˺ astray.

People who claim to believe in conspiracy theories may not actually deep down, which researchers uncovered by asking if they thought Canada had an elite army of genetically engineered, super intelligent, giant raccoons

Scientists at three research institutions capture the pulsing motion of atoms in diamond, uncovering the relationship between the diamond's strain and the behavior of the quantum information hosted within.

Scientists at three research institutions capture the pulsing motion of atoms in diamond, uncovering the relationship between the diamond's strain and the behavior of the quantum information hosted within.

Modern commercial aircraft flying at high altitudes create longer-lived planet-warming contrails than older aircraft, a new study has found.

Researchers have turned concrete from a demolished school building and carbon dioxide (CO2) from the air into new blocks strong enough to build a house with. The process involved grinding the old concrete into powder, reacting it with CO2 from the air, pressurizing it in layers in a mold and finally heating it to form the new block. Instead of making buildings from new concrete only, this technique could offer a way to recycle old materials while also trapping carbon dioxide in the process. The blocks could theoretically be remade again and again, through the same process.

We are constantly surrounded by electromagnetic waves such as Wi-Fi. Researchers tested a device to convert this ambient energy into energy for electronic devices.

We are constantly surrounded by electromagnetic waves such as Wi-Fi. Researchers tested a device to convert this ambient energy into energy for electronic devices.

Researchers report that they have fabricated the world's highest-performing high-temperature superconducting wire segment while making the price-performance metric significantly more favorable.

Researchers report that they have fabricated the world's highest-performing high-temperature superconducting wire segment while making the price-performance metric significantly more favorable.

Researchers have demonstrated a technique for creating sensors that can function both in air and underwater. The approach paves the way for 'amphibious' sensors with applications ranging from wildlife monitoring to biomedical applications.

Researchers at University of Galway have developed a new, portable technology for on-the-spot testing of water quality to detect one of the most dangerous types of bacteria. Ireland regularly reports the highest crude incidence rates of the pathogen Shiga toxigenic Escherichia coli -- STEC for short -- in Europe over the recent years.

An upright neuroimaging device developed by neuroscientists, physicists and engineers allows patients to move around while undergoing a brain scan.

More and more parents are choosing to only have one child. Here’s what the evidence says about how growing up without siblings affects their personality traits and well-being

More and more parents are choosing to only have one child. Here’s what the evidence says about how growing up without siblings affects their personality traits and well-being

How do you get an atmosphere at a world that doesn’t have one and can’t keep one? If it’s the Moon, you simply bombard it for millions of years with tiny meteorites. Also, let it sit in the solar wind and see what happens. Both space-weathering processes create a thin “exosphere” just above the lunar surface.

Scientists call the first process “impact vaporization” and now suspect that it’s a major reason the lunar atmosphere exists. It also helps explain how atmospheric atoms escape from the Moon to space.

A team of scientists at MIT and the University of Chicago recently published a paper describing their research into the space weathering causes of the lunar exosphere. It pinpoints the process of impact vaporization as a major player. “We give a definitive answer that meteorite impact vaporization is the dominant process that creates the lunar atmosphere,” says the study’s lead author, Nicole Nie, an assistant professor in MIT’s Department of Earth, Atmospheric and Planetary Sciences. “The Moon is close to 4.5 billion years old, and through that time the surface has been continuously bombarded by meteorites. We show that eventually, a thin atmosphere reaches a steady state because it’s being continuously replenished by small impacts all over the Moon.”

Tracking the Space Weathering Influence on the Moon’s Atmosphere

Researchers have known about the lunar atmosphere for decades. It was first observed in the 1980s as a layer of atoms hugging close to the surface. The LADEE mission specifically studied that exosphere. The atoms don’t just lie there, however. They bounce around, largely stirred up by constant impacts of tiny objects called micrometeoroids. Those dust-sized particles—along with larger objects smacking into the surface—kick up the lunar soil. That vaporizes some of the atoms of material—including potassium and rubidium. Those atoms are suspended in the thin exosphere. Or, if they get enough velocity in the weak lunar gravity, they escape to space.

The different ways that space weathering can affect the lunar surface. Cartoon by IntrplnetSarah, Creative Commons Attribution-ShareAlike 3.0

The MIT/Chicago team members wanted to prove the exosphere is produced by this impact vaporization component of space weathering. So, they analyzed samples of lunar soil collected during the Apollo missions. They zeroed in on the potassium and rubidium content. That’s because those elements vaporize easily. If the Moon’s atmosphere is atoms suspended above the surface, lighter isotopes of those atoms should be more easily lofted. The heavier isotopes are more likely to settle back in the soil. Furthermore, scientists predict that impact vaporization, and ion sputtering, should result in very different isotopic proportions in the soil. The specific ratio of light to heavy isotopes that remain in the soil, for both elements they tested, eventually proved that impact-related vaporization is an important part of exosphere creation.

The Solar Wind’s Effect on the Moon

The solar wind also plays a role in creating the Moon’s exosphere. That occurs as the ionized particles in the solar wind ions interact with the surface and “sputter off” neutral atoms. Not only does this process contribute to the creation of an exosphere, but it also affects the erosion of materials on the Moon. The current MIT/Chicago study, however, pinpoints the constant rain of impacts as a significant contributor and the two processes work together to create the lunar exosphere.

“With impact vaporization, most of the atoms would stay in the lunar atmosphere, whereas with ion sputtering, a lot of atoms would be ejected into space,” Nie said. “From our study, we now can quantify the role of both processes, to say that the relative contribution of impact vaporization versus ion sputtering is about 70:30 or larger.”

Space Weathering and Future Missions

So, about 70 percent or more of the lunar exosphere is a product of meteorite impacts. The rest occurs thanks to the incessant influence of the solar wind. While this space weathering activity doesn’t produce anything like a breathable atmosphere that future lunar explorers could breathe, it does give insight into the processes that affect the Moon.

Both meteoritic bombardments and solar wind activity pose continuing risks to lunar visitors and their infrastructure. In addition to simply understanding the evolution of the lunar surface and atmosphere, such studies will be useful to anyone who seeks to build—and live—on the Moon in the future.

For More Information

Scientists Pin Down the Origins of the Moon’s Tenuous Atmosphere
Lunar Soil Record of Atmosphere Lost over Eons

The post The Moon’s Atmosphere Comes from Space Weathering appeared first on Universe Today.

It was a tough journey to get here, but I finally arrived in Cape Town last night, exhausted, filthy (no change of clothes from last Saturday until this morning: Wednesday) due to various ariling foulups (thanks, United!).

I am staying with old friends, Martim (botanist) and Rita (evolutionary ornithologist) in a beautiful cottage by the ocean; I’m told that whales sometimes show up below with their calves.  Here’s the view from the balcony outside my bedroom. The Cape of Good Hope—the southern tip of South Africa, is the left tip of the peninsula in the background.

I was supposed to fly out of Dulles Airport in Washinton last Saturday, but after we arrived, there were thunderstorms in the area, and although the sky eventually cleared completely, they still canceled my direct flight to Cape Town.  That was at 10 pm. and 100 people, including me, had to rebook (I was second in line but it still took me 1½ hours). Not only that, but we couldn’t get our luggage, which was loaded into the belly of the plane, for at least six hours (it took two days for me to recover my bag, which they had forced me to check even though it’s way smaller than a roller bag!).  Why an airplane can’t unload its bags and put them on the carousel is still a mystery to me. I rebooked for a flight to Capetown (direct) supposedly leaving tomorrow.

Fortunately, thanks to the grace of Ceiling Cat, my sister and her husband live only 20 minutes from Dulles Airport, and they provided me help and a refuge, especially given that I was basically abandoned by United Airlines and had no place to stay (they don’t give you vouchers for weather-related delays).  I spent two nights with Susan and Bob, and it was great to catch up with them, as I haven’t seen either of them in several years though we talk on the phone occasionally.

They drove me to the airport on Monday to retrieve my bags: but no dice. I was told they were somewhere in the airport but not yet “out,” but I should come back on the next day.   I had no spare clothes, but did have my toiletries and malaria pills and could wash up a bit.  On Tuesday I learned that on the day I was scheduled to fly out (two days later), thunderstorms were predicted AGAIN in Washington. That made me determined to get out of Dodge as fast as possible.  I decided to hie myself to the airport on Tuesday, and if my bag was there, to rebook to Capetown on the spot.

Mirabile dictu, my bag had finally arrived after two days of languishing somewhere in Dulles, and I grabbed it and ran to ticketing, waiting two hours in line to be rebooked.  Fortunately, there was an indirect flight to Cape Town that day, involving three legs:

a.) flying to Newark that evening
b.) catching a plane from Newark to Johannesburg (15 hours) after a 1.5-hour layover
c.) Flying from Joberg to Capetown late on Tuesday evening to meet my friends Marim and Rita (both biologists).

It was a nailbiter as EVERY flight was late, and I often had to run to make my connections, making me even sweatier and dirtier. BUT I MADE IT TO CAPETOWN LAST NIGHT, and South African Airlines even upgraded me to premium class as the plane was full.  I arrived last night, totally exhausted, dehydrated, and fell into a deep sleep immediately, waking up much refreshed after 7½ hours.

Now I’m writing this before I take a luxurious shower, shave, wash my hair, and put on clean clothes. What a luxury!

UPDATE:  Now I’m rested, showered, shaved, scrubbed, and breakfasted, and I feel like a new man.

And as soon as I’m ready, Martim and Rita taking me around the scenic Cederburg Mountains area of SW South Africa (see also here) for a four-day sightseeing and field trip. We will finally see the famous fynbos local vegetation, as well as ancient rock art of the San People (formerly called Bushmen).

As I said previously, the fynbos, now a World Heritage Site, is by far the smallest of the six”floral kingdoms” in the world, with a huge number of exotic and endemic plants seen nowhere else. And the mountains are supposed to be lovely.

Here’s a quick summary of what Martim sent me about our trip. I wouldn’t have been able to do this if I arrived Friday, but now it’s feasible. Here’s the itinerary from Martim:

I opted to not be overambitious regarding trip distances – so the aim is to both get to see a bit of the Karoo landscape (the semi-arid habitat that occupies almost 2/3 of South Africa) and of the mountain landscape of the Cederberg – those mountains I am deeply attached to. The mountains have both Karoo and fynbos (Mediterranean) vegetation. Day 1, we will head to the Karoo, and have something to eat at a ‘padstal’ (= farm stall) in the Karoo (Tankwa padstal). We will sleep at a farm nearby – Hartnekskloof. Day 2, we will head to the Cerderberg, passing by San paintings (Stadsaal and Truitjieskraal), and will stay in Driehoek for two nights (my base in the area). They have a small but very good wine production (their vines are those grown at the highest elevation in South Africa). Day 3 – we can hike straight away from where we are. Day 4 – return to Cape Town. Here’s the map of our itinerary made by Martim: We arrive back here the evening of the 10th, and then Martim has said he would show me some of the sights of Cape Town until I leave for Kruger on the 13th. Those include a trip to Robben Island,  another World Heritage Site, and the island gaol where Nelson Mandela spent 18 of his 27 years of imprisonment before he was freed, won the Nobel Peace Prize, and became President of South Africa. Robben is about 7 km from Capetown, and here’s a photo from Wikipedia. The island has been used to incarcerate political prisoners from the late seventeenth century until apartheid ended in 1996. In the background is Capetown and Table Mountain. South African Tourism from South Africa, CC BY 2.0, via Wikimedia Commons

There is also a new species of penguin for me to see, the African penguin  (Spheniscus demersus), which has a colony near where I’m staying.  It’s endemic to southern South Africa.  And there’s also Table Mountain, which rises high to the north of Cape Town, affording a terrific view.

Because I was late arriving, I extended my stay here for about a week so that I could see more of this lovely town, and then another local botanist, Jeremy, has offered to show me more plants and also take me out to eat and sample the wines of this area, which are famous.

I’m flying up to the Kruger area on Aug. 13, there to see the animals (and Ozy the warthog) and meet my friend Rosemary, who has kindly helped me arrange the northern part of my trip). I’ll stay a few days in a fancy safari lodge (my one nod to luxury), take a two-day trip to the Blyde River Canyon, and then spend several days driving around Kruger Park with Rosemary and a guide, staying in local huts and looking at wildlife, including the famous Southern ground hornbill, Bucorvus leadbeateri.

I return to Cape Town on Aug. 31 and will spend another week here, and to soak up more of the area.

I see from the news that Kamala Harris has picked a VP that is not Shapiro: Governor Tim Walz of Minnesota, and I have no idea whether that’s a canny choice. But I feel very far away from politics and the mishigas that is America now, and I’m grateful for that.

I will be back in Cape Town, hopefully with some good photos, in a few days, and I may be able to post them on the way. But have no fear, there will be pictures.

Stay sane!

Primordial black holes are thought to have formed early in the evolution of the universe. None have been discovered yet but if they do exist and they may be plentiful, drifting almost invisibly through the cosmos, then they might account for dark matter. One possible way to search for them is to see the results of their meals and a bizarre new theory suggests low mass black holes could be captured by neutron stars and become trapped inside, devouring them from within. If these strange objects existed then it would make neutron stars less common in locations where black holes would proliferate as observed around Galactic centre.

Black holes are fascinating objects. Some are formed when supermassive stars die, others (which are theoretical only at this stage) may have formed out of regions of higher density when the universe was young. It is possible they may account for a portion of, or maybe even all of the dark matter that makes up about 27% of the mass-energy content of the universe. Their discovery would certainly help to explain some of the mysteries surrounding dark matter but would also help to explain other observations to; microlensing events, correlations in the X-ray and cosmic infrared background fluctuations and mass, spin and coalescence rates for black holes found by LIGO/Virgo.

LIGO Observatory

In the paper published by Roberto Caiozzo, Gianfranco Bertone and Florian Kuhnel they explore the abundance of sub-stellar mass primordial black holes. They use modern analysis techniques and explore the possibility that the primordial black holes could be captured by neutron stars and sink to its core. Previous studies into this possibility have been undertaken most notably and most recently by Y. G ?enolini, P. D. Serpico, and P. Tinyakov in their paper “Revisiting primordial black hole capture into neutron stars.

The attention of Caiozzo and team focussed upon the innermost parsec of the Milky Way galaxy, the Galactic centre. They chose this location to study neutron star captured primordial black holes due to the expected high density of dark matter and the predicted population of pulsars. I should add here that most neutron stars are seen as pulsars. Pulsars are just neutron stars that rotate fast and we see them as producing pulses of radiation at short intervals often between milliseconds and seconds. It’s thought they should exist in their thousands however to date, hardly any have been found within the innermost region. It’s not known why there are so few however the team postulate that it may be due to disruption by the black holes. 

This image shows a section of the side view of the Milky Way as measured by ESA’s Gaia satellite. The dark band consists of gas and dust, which dims the light from the embedded stars. The Galactic Centre of the Milky Way is indicated on the right of the image, shining brightly below the dark zone. The box to the left of the middle marks the location of the “Maggie” filament. It shows the distribution of atomic hydrogen. The colours indicate different velocities of the gas. Credit: ESA/Gaia/DPAC, CC BY-SA 3.0 IGO & T. Müller/J. Syed/MPIA

Millisecond pulsars (those who spin rate is among the highest) would be an excellent choice for study. They are easy to locate and due to spectroscopic observations, they are thought to exist in large populations in the Galactic bulge, likely also close to Galactic centre. Previous predictions suggest there may be 67 long lived neutron star – X-ray binaries in the innermost region of the centre and these have been shown to be the progenitor of millisecond pulsars. It is therefore reasonable to assume a good population in the Galactic centre. 

The rate of capture of primordial black holes by neutron stars in the Galactic centre is the goal of the paper with existing calculations being revisited to produce a more realistic forecast. The team goes one step further though and look at the likelihood of the collapse of a neutron star given the disruption of a primordial black hole.  The team find however that, having improved all previous models, that the capture of the primordial black holes cannot explain why there are so few missing pulsars / neutron stars around Galactic centre. The disruption of neutron stars and pulsars is simply not likely to occur within their projected lifetime. 

Source : Revisiting Primordial Black Hole Capture by Neutron Stars

The post How a Black Hole Could Eat a Neutron Star from the Inside Out appeared first on Universe Today.