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Meanwhile, in Dobrzyn, Hili can sense the orbit of our planet:

Hili: I suspect that this summer will end.
A: You may be right.

Hili: Podejrzewam, że to lato się skończy.
Ja: Możesz mieć rację.

Tracking data from a pregnant porbeagle shark near Bermuda suggest it was eaten by a great white shark – a kind of predation that has never been seen before

Quartz crystals produce electricity when they are deformed by mechanical stress, which may explain how enormous chunks of gold can form in inert rock

Stem cells made in the lab may one day aid cancer treatment by reducing our reliance on donors

Clouds can trap heat or reflect it away from Earth, making their impact on global warming extraordinarily hard to predict. Now, new ways of studying them are lifting the fog

From Michel Houellebecq to Booker-longlisted Richard Powers and Rachel Kushner, there is plenty of excellent science fiction to read this September

NASA is investigating a strange noise coming through the speaker on Boeing’s Starliner capsule, which has been beset with technical issues

Advances in generative AI mean fake images, videos, audio and bots are now everywhere. But studies have revealed the best ways to tell if something is real

Using LLM tools to tackle AI-driven science misinformation head-on

The post LLMs: Fighting Fire with Fire first appeared on Science-Based Medicine.

In July 2020, China’s Tianwen-1 mission arrived in orbit around Mars, consisting of six robotic elements: an orbiter, a lander, two deployable cameras, a remote camera, and the Zhurong rover. As the first in a series of interplanetary missions by the China National Space Administration (CNSA), the mission’s purpose is to investigate Mars’s geology and internal structure, characterize its atmosphere, and search for indications of water on Mars. Like the many orbiters, landers, and rovers currently exploring Mars, Tianwen-1 is also searching for possible evidence of life on Mars (past and present).

In the almost 1298 days that the Tianwen-1 mission has explored Mars, its orbiter has acquired countless remote-sensing images of the Martian surface. Thanks to a team of researchers from the Chinese Academy of Sciences (CAS), these images have been combined to create the first high-resolution global color-image map of Mars with spatial resolutions greater than 1 km (0.62 mi). This is currently the highest-resolution map of Mars and could serve as a global base map that will support crewed missions someday.

The team was led by Professor Li Chunlai from the National Astronomical Observatories of China (NOAC) and Professor Zhang Rongqiao from the Lunar Exploration and Space Engineering Center. They were joined by multiple colleagues from the Key Laboratory of Lunar and Deep Space Exploration, the Institute of Optics and Electronics, the University of Chinese Academy of Sciences, and the Shanghai Institute of Technical Physics. The paper detailing their research, “A 76-m per pixel global color image dataset and map of Mars by Tianwen-1,” recently appeared in the journal Science Bulletin.

The optical camera (MoRIC) and imaging spectrometer (MMS) onboard the Tianwen-1 orbiter were used to obtain remote-sensing images of the entire Martian surface. Credit and ©: Science China Press

Several global maps of Mars have been created using remote-sensing images acquired by instruments aboard six previous missions. These include the visual imaging systems of the Mariner 9 probe, the Viking 1 and 2 orbiters, the Mars Orbiter Camera-Wide Angle (MOC-WA) aboard the Mars Global Surveyor (MGS), the Context Camera (CTX) aboard the Mars Reconnaissance Orbiter (MRO), the High-Resolution Stereo Camera (HRSC) of Mars Express (MEX), and the Thermal Emission Imaging System (THEMIS) on the Mars Odyssey orbiter.

However, these maps all had a spatial resolution significantly less than what the CAS team created using images acquired by the Tianwen-1 orbiter. For example, the MGS MOC-WA Atlas Mosaic has a spatial resolution of 232 meters per pixel (280 yards per pixel) in the visible band, and the THEMIS Global Mosaic of the Mars Odyssey mission offers a spatial resolution of approximately 100 m/pixel (~110 ft/pixel) in the infrared band. While the MRO Global CTX Mosaic of Mars covered 99.5% of the Martian surface (88° north to 88° south) in the visible band, it has a spatial resolution of about 5 m/pixel (5.5 yards/pixel).

There has also been a lack of global color images of Mars with spatial resolutions of a hundred meters (110 yards) or higher. In terms of global color images, the Mars Viking Colorized Global Mosaic v1 and v2 have spatial resolutions of approximately 925 m/pixel and 232 m/pixel (~1010 and 255 yards/pixel), respectively. Meanwhile, the MoRIC instrument acquired 14,757 images during the more than 284 orbits executed by the Tianwen-1 orbiter, with spatial resolutions between 57 and 197 m (62 and 215 yards).

During this same time, Tianwen-1’s Mars Mineralogical Spectrometer acquired a total of 325 strips of data in the visible and near-infrared bands, with spatial resolutions varying from 265 to 800 m (290 to 875 yards). The collected images also achieved global coverage of the Martian surface. Using this data, Professor Li Chunlai, Professor Zhang Rongqiao, and their colleagues processed the image data that led to this latest global map of Mars. The team also optimized the original orbit measurement data using bundle adjustment technology.

(a) Level 2C data product as the input, (b) image corrected by atmospheric correction, (c) image corrected by photometric correction, and (d) image corrected after color correction. Credit and ©: Science China Press

By treating Mars as a unified adjustment network, the team was able to reduce the position deviation between individual images to less than 1 pixel and create a “seamless” global mosaic. The true colors of the Martian surface were achieved thanks to data acquired by the MMS, while color correction allowed for global color uniformity. This all culminated with the release of the Tianwen-1 Mars Global Color Orthomosaic 76 m v1, which has a spatial resolution of 76 m (83 yards) and a horizontal accuracy of 68 m (74 yards).

This map is currently the highest-resolution true-color global map of Mars and significantly improves the resolution and color authenticity of previous Mars maps. This map could serve as a geographic reference for other space agencies and partner organizations to map the Martian surface with even greater resolution and detail. It could also be used by space agencies to select sites for future robotic explorers that will continue searching for clues about Mars’ past. It could also come in handy when NASA and China send crewed missions to Mars, which are slated to commence by the early 2030s or 2040s.

Further Reading: Eureka Alert!, Science Bulletin

The post A Global Color Map of Mars, Courtesy of China’s Tianwen-1 Mission appeared first on Universe Today.

https://traffic.libsyn.com/secure/sciencesalon/mss463_Ben_Goertzel_2024_09_01.mp3 Download MP3

Dr. Ben Goertzel is a cross-disciplinary scientist, entrepreneur and author. Born in Brazil to American parents, in 2020 after a long stretch living in Hong Kong he relocated his primary base of operations to a rural island near Seattle. He leads the SingularityNET Foundation, the OpenCog Foundation, and the AGI Society which runs the annual Artificial General Intelligence conference.

Dr. Goertzel also chairs the futurist nonprofit Humanity+, serves as Chief Scientist of AI firms Rejuve, Mindplex, Cogito, and Jam Galaxy, all parts of the SingularityNET ecosystem, and serves as keyboardist and vocalist in the Jam Galaxy Band, the first-ever band led by a humanoid robot.

As Chief Scientist of robotics firm Hanson Robotics, he led the software team behind the Sophia robot; as Chief AI Scientist of Awakening Health he leads the team crafting the mind behind Sophia’s little sister Grace.

Dr. Goertzel’s research work encompasses multiple areas, including artificial general intelligence, natural language processing, cognitive science, machine learning, computational finance, bioinformatics, virtual worlds, gaming, parapsychology, theoretical physics and more. He has published 25+ scientific books, ~150 technical papers, and numerous journalistic articles, and given talks at a vast number of events of all sorts around the globe.

Before entering the software industry Dr. Goertzel obtained his PhD in mathematics from Temple University in 1989 and served as a university faculty in several departments of mathematics, computer science and cognitive science, in the US, Australia and New Zealand. His new book is The Consciousness Explosion: A Mindful Human’s Guide to the Coming Technological and Experiential Singularity.

Shermer and Goertzel discuss:

• Natural Intelligence and Artificial Intelligence
• General Intelligence (g) and Artificial General Intelligence (AGI)
• The alignment problem
• Consciousness and sentience
• Zombies and the Hard Problem of Consciousness
• Data, Sophia, and other robots
• Altered States of Intelligence
• Mind uploading and the self
• How would we know if an AI system was sentient?
• Can AI systems be conscious?
• Self-driving cars
• AI dystopia
• AI utopia
• AI protopia
• UBI
• What set of values should AI be aligned with, and what legal and ethical status should it have?
• Can AGI solve political and economic problems?

If you enjoy the podcast, please show your support by making a $5 or $10 monthly donation.

Wearable, long-term continuous heart monitors helped identify 52% more cases of atrial fibrillation compared to usual care, but that did not lead to a reduction in hospitalizations due to stroke, according to a new study.

Cosmologists have long hypothesized that the conditions of the early universe could have caused the formation of black holes not long after the Big Bang. These ‘primordial black holes’ have a much wider mass range than those that formed in the later universe from the death of stars, with some even condensed to the width of a single atom.

No primordial black holes have yet been observed. If they exist, they might be an explanation for at least some of the ‘dark matter’ in the universe: matter that does not appear to interact with normal matter through electromagnetism, but does affect the gravitational dynamics of galaxies and other objects in the universe.

Now, we might have a new way to detect primordial black holes, although in a severely limited form.

This method comes via gravitational waves.

This illustration shows the merger of two black holes (detected by LIGO on Dec 26, 2016) and the gravitational waves that ripple outward as the black holes spiral toward each other. Credit: LIGO/T. Pyle

First detected in 2015 by the LIGO gravitational wave observatory, gravitational waves are ‘ripples’ in spacetime caused by dramatic events in the universe – most often the collision of giant objects like stellar mass black holes and neutron stars. About 90 confirmed gravitational wave sources have been found by the LIGO-Virgo-KAGRA (LKV) program since 2015.

In a research note published this month, Harvard astrophysicist Avi Loeb examined whether the LKV detectors could catch the signature of primordial black holes – specifically those racing by near the speed of light – or other similar objects moving at high speeds.

“All gravitational wave sources detected sofar involve mergers of stellar-mass astrophysical objects, such as black holes or neutron stars, at cosmological distances,” wrote Loeb in a Medium post in August. But these are not the only possible sources.

“Imagine a relativistic object moving near the speed of light within a distance from LIGO that is comparable to the radius of the Earth. At closest approach, such an object would generate a gravitational signal,” one heavily dependant on its mass and the speed at which it is moving, says Loeb.

With LKV’s current capabilities, the detectors would be able to see any objects moving near to the speed of light with a mass of 100 megatons (the mass of a smallish asteroid several hundred meters across), but only if it came within half the Earth’s diameter of the detectors.

In other words, the LKV detectors would have noticed if an object of this mass passed through the Earth, or very near its surface, in the decade since 2015, if it was traveling at very high speeds.

Of course, if an asteroid of that mass hit Earth at that speed, we’d be well aware of it from the devastating impact. As such, this capability is really of interest particularly for compact objects like primordial black holes, with diameters the size of an atom or smaller, that might pass nearby or even through the Earth without anyone noticing.

No such object has been seen by the LKV detectors.

It is not a surprising result, given that this is a very limited detection capability. It doesn’t tell us about objects further than ~6000 kilometers from Earth’s surface, and also fails to detect slower moving objects.

Future gravitational wave detectors, like ESA’s LISA detector, expected to launch next decade, will expand this range, though not by a lot.

Still, when you are seeking answers to some of the hardest questions in the universe, it’s worth checking where you can. This particular stone hasn’t been left unturned.

Read the Research Note in RNASS here.

The post Gravitational Wave Observatories Could Detect Primordial Black Holes Speeding Through the Solar System appeared first on Universe Today.

I think I’ve already mentioned some things about the giant and fantastic Kruger National Park in NE South Africa, but let’s start with the basics, which means some information and a map from Wikipedia:

Kruger National Park (Tsonga: [ˈkrúːɡà]; Afrikaans: [ˈkry.(j)ər]) is a South African National Park and one of the largest game reserves in Africa. It covers an area of 19,623 km2 (7,576 sq mi) in the provinces of Limpopo and Mpumalanga in northeastern South Africa, and extends 360 km (220 mi) from north to south and 65 km (40 mi) from east to west. The administrative headquarters are in Skukuza. Areas of the park were first protected by the government of the South African Republic in 1898, and it became South Africa’s first national park in 1926.

Here it is below, in red. It’s HUGE! It’s bordered on the east mostly by Mozambique, but we also visited a spot in the north called “Crook’s Corner,” where three countries (South Africa, Mozambique, and Zimbabwe) meet. You can see that spot at the top of the reddish park map below, and it’s where poachers and other criminals used to flee one country to avoid the law by simply stepping across the border (this involves crossing a river) to to one of the other two countries, where they were from from pursuit. Nowadays immigrants from Mozambique cross the river into Kruger seeking a better life in South Africa.

For those who know the park, we entered at the Phalaborwa gate, did a zig-zag heading generally north, often taking dirt roads and taking diversions based on what Isaac heard from his fellow guides and from his own instincts.

We exited the park at the Orpen gate after having stayed four nights in comfortable and inexpensive bungalows: two at Shingwedzi and two at Pafuri. We had about 4.5 days of wildlife watching, at least eight hours a day. I’ll try to reconstruct a map of our travels in the next few days.

Go here to see a good map of the park that includes these locations. If you look at the map, you’ll see that to its west Kruger is surrounded by private game parks and nature reserves. Almost none of these have fences, allowing the animals to transit as they please over a huge area.

But a last meal before I left. A quarter bunny chow in Hoedspruit with beef (the mutton was better but this is still good). It’s filling, cheap, and tasty: a hollowed- out bread bowl (a quarter of a loaf) filled with curry. Note the perfucnctory “salad” to the side.

And the Hoedspruit version of a chocolate milkshake, which was very good:

On to the park. I recommend clicking on the photos to enlarge them.

This is the Phalaborwa gate where you formally enter the park in the north (there are nine entrance gates). You pay by the day on a sliding scale, with South African residents paying about a quarter of what foreigners do, which is fair given the difference in income. The money is for badly needed conservation fees.

Gates are strictly monitored, and open and close at roughly 6 a.m. and 6 p.m. respectively. This is also true of the 12 main “bush camps” where you can stay in well-equipped huts (there are also a couple of fancy private lodges, and “bushveld camps” with fewer facilities). If you are late and the camp is closed, you can still get in (with a reservation), but you have to pay a substantial “fine.”

At the entrance, and throughout the park, there are “sightings boards” showing which charismatic animals have been seen where and when (yesterday or today).  Note that they do NOT post sightings of rhinos because the poachers are, above all, after rhino horns, used in traditional Chinese medicine.

As I mentioned in previous posts. The rangers try to anesthetize all the park’s rhinos and cut off their two horns to prevent the animals from being killed by poachers, but the horns grow back and the process has to be repeated every four years or so.

Our first sighting of animals, apparently a pair of storks. I can’t remember the species.

Our guide Isaac told us that this is a group of social spiders who live in a sac attached to a large, insect-catching web. I believe this is a group of Stegodyphus mimosarum, the African social velvet spider. Individuals in a colony share food and care of the young spiders:

This zoomed-in shot of a raptor with a white chest may be an African hawk-eagle (Aquila spilogaster), but I can’t be sure. Later on we saw and identified a similar-looking species, the booted eagle (Hieraaetus pennatus).

Our first sighting of a mammal that became quite familiar to us, the African bush elephant (Loxodonta africana). (There’s also an African forest elephant in the same genus.) According to a recent census, there are roughly 13,0o0 elephants in Kruger, and the numbers are rising (there were only 725 in 2006).

There is continual debate about whether the increasing population poses a danger to the park, as they knock down trees and displace other species, and for a while they “culled” (i.e., shot) elephants to control the population. Of course big-game hunters in other places shoot them as trophies (an execrable practice), but it’s hard to think about mass killings of these beautiful and highly intelligent creatures when you’ve spent some time watching them.

Here are some small Lala Palms (Hyphaene coriacea). These are small ones, but, as Wikipedia notes,

The spongy pulp of the hard, brown fruit is edible and the fruit is eaten and sold in Madagascar and in eastern Africa; its Swahili name is Mkoma. The flavour has been compared to raisins and raisin bran.

Hippos (Hippopotamus amphibius) are hard to see out of the water, as they prefer spending their days submerged except for their eyes and nose, and generally come out of the water to graze only at night.  (Their skins are very sensitive to sunlight, something you’d think natural selection should remedy.) But on cool days you can see them grazing, always near water.

Here are two. They are considered among the world’s most dangerous animals because they are aggressive, unpredictable, and can run surprisingly fast.  500 people per year are killed by hippos, compared to only 22 for lions, but people are far more scared of lions.

This is a poorly-exposed photo that I included because it’s part of my “animals crossing roads series”.  These are very common antelopes that get no respect because they’re so common in the park: the impala (Aepyceros melampus). They’re everywhere and one tends to overlook them, but they’re very beautiful. Males have horns and females don’t, so these are females.

A larger antelope, the greater kudu (Tragelaphus strepsiceros) with the characteristically spiral horns found only in males. They’re easily identified because both sexes are striped.

Remember, since you’re not allowed to leave your car, all these animals were photographed through open windows in our vehicle. Ergo, most were pretty close to the roadside. Most mammals, save zebras and some antelopes like impala, pretty much ignore cars, although a big bull elephant in the road threatened to charge us after spitting a rare piece of paper at us. Isaac, knowing the signs of elephant aggression (tilting the head sideways is a telling one), backed up the car slowly, and the elephant strode away.

Elephant crossing the road:

A Burchell’s zebra (Equus quagga burchellii) crossing the road. You will see several of these photos in the coming days because it is a ZEBRA CROSSING (in the UK that’s the name for a pedestrian crosswalk).

A rare spot despite its name, here are a few common tsessebe (Damaliscus lunatus lunatus) crossing the road.

A better shot of the tsessebe. In this species both sexes have horns. Horns in males only are a sign of sexual selection, but in some species males have larger horns than females, also indicating sexual selection but likely natural selection as well, giving some reproductive advantage to horned females.

Fun tsessebe facts from Wikipedia:

Several of their behaviors strike scientists as peculiar. One such behavior is the habit of sleeping tsessebe to rest their mouths on the ground with their horns sticking straight up into the air. Male tsessebe has [sic] also been observed standing in parallel ranks with their eyes closed, bobbing their heads back and forth. These habits are peculiar because scientists have yet to find a proper explanation for their purposes or functions

A herd of one of Africa’s most dangerous animals, the African buffalo (Syncerus caffer), a member of the “big five” referred to below; these are animals that are regarded as the most dangerous to hunt and kill with either spear or gun (the other four are lions, rhinos, leopards, and elephants):

One of the “big five” African game, it is known as “the Black Death” or “the widowmaker”, and is widely regarded as a very dangerous animal. African buffaloes are sometimes reported to kill more people in Africa than any other animal, although the same claim is also made of hippopotamuses and crocodiles. These numbers may be somewhat overestimated; for example, in the country of Mozambique, attacks, especially fatal ones, were much less frequent on humans than those by hippos, and especially, Nile crocodiles. In Uganda, on the other hand, large herbivores were found to attack more people on average than lions or leopards and have a higher rate of inflicting fatalities during attacks than the predators (the African buffalo, in particular, killing humans in 49.5% of attacks on them), but hippos and even elephants may still kill more people per annum than buffaloes. African buffaloes are notorious among big-game hunters as very dangerous animals, with wounded animals reported to ambush and attack pursuers.

In male buffalo, the horns grow together, fusing in the middle of the head in a structure known as a “boss.” This one doesn’t have a boss:

Here’s a “boss” male with the fused horns, as well as an oxpecker nibbling at his nose.

Below: the most iconic tree in Africa, the Baobab (Adansonia digitata). I didn’t see it leafed out (that’s during the African summer), but it’s unmistakable because of its large, bulbous trunk (It’s actually classified not as a tree but a succulent.) There are 8 species, but only this one is endemic to mainland Africa (6 others are native to Madagascar and one to Australia.

They can get very old (carbon dating puts an age limit of about 2,000 years). The tree has many uses for man, beast, and bird. Young leaves can be stewed as a vegetable, the roots and fruits are edible, and the seeds can be made into a flour. The bark can be made into fiber and clothes, and, in times of drought, elephants eat the water-rich underbark. And as for birds, see the second photo below.

There are often signs under baobabs in the park, and here’s one of them. What kind of miscreant would throw stones at owl holes?

The lovely impala lily (Adenium multiflorum), native to eastern and southern Africa. It’s a small succulent tree and was blooming everywhere in the dry winter season of our visit. The flowers are gorgeous and trees are planted widely around the camps.

Another baobab. I’d love to see these in the wet summer.

Isaac, the crack spotter, suddenly asked me out of nowhere, “Would you like to see a giraffe lying down?” I said, “Sure,” and asked him if this was an unusual event. He said “yes”.  Sure enough, Isaac had spotted two of them far before I could see them:

You may have wondered if giraffes sleep. The answer is, “Yes, but not much,” probably because they have to keep alert for predators (they can be taken down by lions, leopards, hyenas, and wild dogs, all of whom first go for the legs). Here’s some info about giraffe sleep from one website:

To start, let’s clarify that giraffes only sleep a few hours a day.

Some giraffes don’t even sleep that much. In captivity, adult giraffes have been observed sleeping as much as four and a half hours a day. In the wild, giraffes might only sleep about 40 minutes a day—and only about three to five minutes at a time.

Researches have observed three types of sleep in giraffes: standing, recumbent, and paradoxical. The latter sleep type is similar to REM (rapid eye movement) sleep. Standing sleep is characterized by a giraffe standing up, yet motionless, with its head tilted slightly more forward than it is when awake. This is thought to be essentially a light nap for giraffes and makes up a majority of their sleep.

During recumbent and paradoxical sleep, a giraffe can be observed lying down with their legs folded under them, their neck turned and arched backward and their heads resting on their rumps or the ground—similar to a swan.

When they drink at a waterhole, giraffe splay their legs widely to lower their body, allowing that long neck to reach the water.

A non-napping giraffe:

Zebra crossing!

We crossed the Tropic of Capricorn, where it’s allowed to leave the vehicle. I love official lines like the Equator (which I’ve also straddled) and borders between countries.

The Tropic of Capricorn is explained in the second photo below: it’s the furthest latitude south where the Sun appears directly overhead. That event occurs around December 21, the Winter Solstice in the northern hemisphere. Wikipedia notes that this is “the dividing line between the Southern Temperate Zone to the south and the Tropics to the north.”

Of course I had to straddle it: the line of rocks running between my legs.  Now I can say that I’ve stood astride this line, as well as the Equator. (I can’t remember standing on the Tropic of Cancer; the closest place to Chicago would be in Mexico.)

The explanation:

Two more giraffes. I couldn’t get enough of these majestic and beautiful animals. They’ve evolved, of course, to access leaves high up on trees that other animals can’t reach: an adaptation that comes with several costs.  They give birth standing up and the babies have a long tumble to the ground, which animates them to start their lives.

Here’s a giraffe giving birth in the wild. The baby takes its first wobbly steps within only a few minutes:

I believe I’ve discussed before the phenomenon of “dagga boys”: African buffalo who have been expelled from their herd because they’re old and can’t hold a position in the hierarchy (ca. ten years). They must thus wander, solitary or with a couple of other dagga boys, until they die or are taken down by predators like lions. They often roll in the mud because they have skin conditions, and are especially dangerous because, lacking the defense of their herd, they’re prone to attack.

In a later installment we’ll see the remains of a dagga boy killed by lions. These solitary animals, I think, must be lonely, and I find them ineffably sad. But such is nature.

A lovely male of the Greater Kudu.

And a giraffe sticking out its tongue:

One of the most amazing things we saw on day 1 (and remember, this is only the first of five days) was a huge herd of elephant digging for water in a dry river bed. Apparently elephants have a way of detecting water close to the surface, and when they find it, and are thirsty, they use their legs, tusks, and trunk to excavate a well that can be more than a meter deep. Here’s one female digging for water, and she found it:

This is only a small number of the more than fifty elephants I counted in the vicinity, and they’re all either digging for water or trying to get water from holes dug by others. Naturally the diggers wants a monopoly on their water and try to drive interlopers away, except for mothers who allow their babies to drink with them.  An elephant can take in 100 liters at a time, and about 240 liters per day.

Two photos of a mom allowing her baby to drink:

A bit more than half the group (I couldn’t get them all in one photo):

Finally, a male giving us the stink eye. Notice also that there are impala, kudu, and a single Marabou Stork  (Leptoptilos crumenifer) to the right of the elephant.

That was just Day One. There’s lots to come, but we made camp before closing time and had dinner (there are small and inexpensive restaurants in the camps).

More when I get time, probably tomorrow.

Meanwhile, in Dobrzyn, Szaron gives Hili an enigmatic reply:

Hili: Are you thinking?
Szaron: No, I’m still asleep.

Hili: Czy myślisz?
Szaron: Nie, nadal śpię.

Watching the Olympics recently and the amazing effort of the hammer throwers was a wonderful demonstration of the radial velocity method that astronomers use to detect exoplanets. As the hammer spins around the athlete, their body and head bobs back and forth as the weight from the hammer tugs upon them. In the same way we can detect the wobble of a star from the gravity of planets in orbit. Local variations in the stars can add noise to the data but a team of researchers have been studying the Sun to help next-generation telescopes detect more Earth-like planets. 

To date 5,288 exoplanets have been discovered, that’s 5,288 planets in orbit around other star systems. Before 1992 we had no evidence of other planetary systems around other stars. Since then, and using various methods astronomers have detected more and more of the alien worlds. Techniques to detect the exoplanets range from monitoring starlight for tiny dips in brightness to studying the spectra of stars. Just over 1,000 exoplanets have been discovered using the radial technique making it one of the most successful methods. 

“Icy and Rocky Worlds” is a new exoplanet infographic from Martin Vargic, an artist and space enthusiast from Slovakia. It’s available as a wall poster on his website. Image Credit and Copyright: Martin Vargic.

The local variations in the properties of stars has made it difficult to find smaller planets using the radial technique but a team of astronomers led by Eric B. Ford from the Department of Astronomy and Astrophysics at the Penn State University has just published a report of their findings following observations of the Sun. Observations of the Sun between January 2021 and June 2024 using the NEID Solar spectrograph at the WIYN Observatory have informed their study. 

A gas giant exoplanet [right] with the density of a marshmallow has been detected in orbit around a cool red dwarf star [left] by the NASA-funded NEID radial-velocity instrument on the 3.5-meter WIYN Telescope at Kitt Peak National Observatory, a Program of NSF’s NOIRLab. The planet, named TOI-3757 b, is the fluffiest gas giant planet ever discovered around this type of star.

Across the 3 years and 5 months of observations, the team identified 117,600 features which are not likely to have been caused by the weather, hardware or calibration issues so they could be used for their study. Given that the distance between the Sun and Earth is precisely known the team can use this to analyse solar observations and measure other solar variability. 

Impressively the team have been able to show that the NEID instrumentation is able to measure radial velocity of the Sun accurate to 0.489 m/s-1. Using this data the team conclude that Scalpels algorithm (a technique developed for medicine that uses machine learning to analyse and extract data from images) performs particularly well. It can reduce the root mean square (used to analyse signal amplitude) of solar radial velocity from over 2 m/s-1 down to 0.277 m/s-1! 

The results are significantly better than previous studies at removing solar variability from its radial velocity observations. This suggests that the next generation of exoplanet radial velocity instruments are capable, at least technically at detecting Earth-massed planets orbiting a star like the Sun. This does of course require sufficient observing time which the team estimate would be about 103 nights of observations. 

Source : Earths within Reach: Evaluation of Strategies for Mitigating Solar Variability using 3.5 years of NEID Sun-as-a-Star Observations

The post By Watching the Sun, Astronomers are Learning More about Exoplanets appeared first on Universe Today.

Our Sun is one of the most fascinating objects in the universe and photographing it with specialized equipment to capture its splendor and beauty has become increasingly more common around the world. This is most evident with the work obtained by renowned astrophotographer, Andrew McCarthy (@AJamesMcCarthy), who owns Cosmic Background Studios in Florence, Arizona.

On July 27, 2024, McCarthy posted an image of the Sun on X (formerly known as Twitter) taken with his specialized equipment designed to safely photograph our life-giving star, which revealed active coronal loops and plasma within the solar chromosphere that are some of the many intriguing features of the Sun. However, McCarthy is quick to mention in his post that this image isn’t entirely genuine, but a combination of several attributes.

My recent solar print release drew a lot of questions about some of the features of the sun… particularly in this close up. The second post in this thread features a time-lapse showing how these coronal loops moved over time. pic.twitter.com/AdzVOhr55S

— Andrew McCarthy (@AJamesMcCarthy) July 27, 2024

“This image is a piece of digital art that combines real astrophotos with some rendered features,” McCarthy tells Universe Today. “I captured the solar chromosphere with a solar-modified telescope, designed to block out the photosphere’s light to reveal the faint structure in the Sun’s atmosphere. The corona was captured during April’s total solar eclipse. Between the large-scale and small-scale structures of the photos, there’s a lot going on invisibly with the Sun’s magnetic field. Using some real data of that field as reference, I rendered coronal loops in a plausible way to show a more complete image of the scales of magnetic structure on the Sun.”

The solar chromosphere is the second layer of the Sun’s atmosphere residing above the Sun’s surface, known as the photosphere (4,130 to 6,330 °C), and below the corona (just under 1,000,000 °C). The chromosphere is known for its red color that is observed hydrogen-alpha electromagnetic emissions and extends between 3,000 to 5,000 kilometers (1,900 to 3,100 miles) in height, which is approximately one percent of the Sun’s radius, while exhibiting temperatures ranging between 3,500 to 35,000 °C. It is the solar chromosphere that is responsible for producing coronal loops, which are arch-like structures produced by the Sun’s magnetic field activity, typically occurring from sunspots. In addition to the incredible image, McCarthy also posted an equally incredible 14-second video of these incredible features in action.

You can see the plasma guided back onto the solar chromosphere by the magnetic loops in this time-lapse. Wild!

See the full photo of the sun featuring the solar corona on my website here. I also have limited edition prints available for a short time. https://t.co/jHkqjin72c pic.twitter.com/sBK0N8KFMV

— Andrew McCarthy (@AJamesMcCarthy) July 27, 2024

McCarthy tells Universe Today, “These are an example of the magnetic loops captured authentically by isolating the plasma caught in them. This produces coronal rain, plasma raining back onto the photosphere.”

Our Sun is essentially a giant ball of plasma that is undergoing constant change, both within its interior and on its surface, including radio waves, solar wind, and magnetic field. Studying the magnetic field teaches scientists about 22-year cycles where the poles of the magnetic field flip and then return to their initial position, resulting in increased solar activity occurring over 11-year cycles during each transition. This increased magnetic field activity results in increased solar wind emanating from the Sun, leading to solar storms that can strike Earth, causing auroras near our planet’s poles while also harming satellites in orbit and electronic ground stations. One of the most revered incidents of solar storms on Earth was the Carrington Event, which occurred between September 1-2, 1859, resulting in worldwide auroras and telegraph station fires across the globe, as well.

Scientists who study the Sun and its various features are known as solar physicists who use a combination of ground- and space-based telescopes to obtain data regarding the Sun’s activity on a 24/7 basis. Arguably one of the most successful missions to study the Sun is NASA’s Parker Solar Probe, which was launched on August 12, 2018, and has traveled closer to the Sun than any human-made spacecraft in history, coming within 7.26 million kilometers (4.51 million miles) from the Sun’s surface in September 2023 and again in March 2024. During its mission, the Parker Solar Probe encountered magnetic field switchbacks, which is when the magnetic field reverses its direction, resulting in heating the solar corona.

Examples of ground-based telescopes that study the Sun include the Mauna Loa Solar Observatory, which like McCarthy, uses specialized equipment to safely study the Sun and its various features, providing data and images that can be used for research and public outreach. Therefore, how can McCarthy’s work be used for scientific research, and has his past work been used for scientific research purposes?

“This image is in no way intended for scientific research, but rather a product of scientific research,” McCarthy tells Universe Today. “That said, hydrogen alpha images of the sun offer real insight into the behavior of the sun’s magnetic field and are used by scientists worldwide. Amateurs capturing the sun in detail can complement the data produced by professional observatories on earth and in space and play a role in public outreach that can sometimes be lacking by professional institutions.”

McCarthy has become well-known for capturing incredible images of the Sun and sharing them with the public, including breathtaking images and videos of tornado-like prominences emanating from the solar chromosphere in March 2023, which also captured images of the solar corona. Along with these images, McCarthy provides detailed descriptions of the events occurring in his work with the goal of exciting the public about the Sun and its many incredible features.

“The Sun is unique in that every time I photograph it, it looks completely different,” McCarthy tells Universe Today. “The features are always changing. For that reason, it’s a target I will keep coming back to. While intended purely as a piece of digital art, my goal with this piece was to inspire people to ponder our fragile existence kept in balance by our host star. Hopefully it inspires more people to study it, as it gives us a better understanding of this universe we live in!”

What new discoveries will we make about our Sun in the coming years and decades? Only time will tell, and this is why we science!

As always, keep doing science & keep looking up!

Links:

Andrew McCarthy: X (Twitter) & Website

The post Coronal Loops-Digital Art Combination Captures Power of the Sun, Rendered by Andrew McCarthy appeared first on Universe Today.

The Standard Model describes how the Universe has evolved at large scale. There are six numbers that define the model and a team of researchers have used them to build simulations of the Universe. The results of these simulations were then fed to a machine learning algorithm to train it before it was set the task of estimating five of the cosmological constants, a task which it completed with incredible precision. 

The Standard Model incorporates a number of elements; the Big Bang, dark energy, cold dark matter, ordinary matter and the cosmic background radiation. It works well to describe the large scale structure of the Universe but there are gaps in our understanding. Quantum physics can describe the small scale of the Universe but struggles with gravity and there are questions around dark matter and dark energy too. Understanding these can help in our understanding of the evolution and structure of the Universe. 

Enlarged region of the Saraswati Supercluster, the largest known structure in the Universe, showing the distribution of galaxies. Credit: IUCAA

A team of researchers from the Flatiron Institute have managed to extract some hidden information in the distribution of galaxies to estimate the values of five of the parameters. The accuracy was a great improvement on values that were attained during previous attempts. Using AI technology the team’s results had less than half the uncertainty for the element that describes the clumpiness of the Universe than in the previous attempt. Their results also revealed estimates of other parameters that closely resembled observation. The paper was published in Nature Astronomy on 21 August. 

The team generated 2,000 simulated universes after carefully specifying their cosmological parameters. These included expansion rate, the distribution and clumpiness of ordinary matter, dark matter and dark energy and using these the team ran the simulations. The output was then compressed into manageable data sets and this was used to compare against over one hundred thousand real galaxies data. From this, it was possible for the researchers to estimate the parameters for the real Universe. 

The parameters the team managed to fine tune are those that describe how the Universe operates at the largest scale. These are essentially, the settings for the Universe and include the amount of ordinary matter, dark matter, dark energy, the conditions following the Big Bang and just how clumpy the matter is. Previously these settings were calculated using observations from the structure of galaxy clusters. To arrive at a more accurate group of settings observations needed to go down to smaller scale but this has not been possible. 

The full-sky image of the temperature fluctuations (shown as color differences) in the cosmic microwave background, made from nine years of WMAP observations. These are the seeds of galaxies, from a time when the universe was under 400,000 years old. Credit: NASA/WMAP

Instead of using observations, the team used their AI approach to extract the small scale information that was hidden in the existing observational data. At the heart of the approach was the AI system that learned how to correlate the parameters with the observed structure of the Universe – but at small scale. 

In the future the team hope to be able to use their new approach to solve other problems. The uncertainty about the Hubble Constant is an example where the team hope AI can help to fine tune its value. Over the next few years though, and as observational data becomes more detailed both Hubble’s Constant and the Settings of the Universe will become far better understood along with our understanding of the Universe. 

Source : Astrophysicists Use AI to Precisely Calculate Universe’s ‘Settings’

The post Estimating the Basic Settings of the Universe appeared first on Universe Today.

Can you spot the African bush elephant (Loxodonta africana) in this photo? It’s not that hard, but it shows you how well camouflaged they are, although there’s really nothing they need to hide from (the only predators go after babies, who are well protected by their mothers, and of course they’re herbivores.)  In fact, this one’s so easy I don’t think I need to give a reveal.

It was taken in Kruger, and presages my five posts on the five days we spent in the park. Click photo to enlarge.

I’m back in Cape Town, and preparing Kruger Post #1. In the meantime, have another read about college miscreants:

See below. I told you so, but this isn’t rocket science. Anybody with two neurons to rub together could have guessed the protest engine would rev up when classes begin again, for, especially at elite schools, students are more interested in enforcing what they consider Social Justice on others than engaging in learning.

The article below (click to read), written by Judy Lucas four days ago, was published in The Ithaca Voice, the local paper. Click headline to read:

An excerpt:

The spring semester at Cornell University ended with protests, as students erected an encampment on the Arts Quad to oppose the university’s ties to institutions supporting the Israeli state. The war in Gaza raged on through the summer, with reports of thousands of more lives lost. Cornell’s fall semester started much like its last one ended.

A crowd of about 150 student protestors at Cornell University marched into a campus dining hall Monday, the first day of classes, where speakers renewed the call for the university to divest from any institutions supplying weapons and support to the Israeli military in the war against Hamas, among a set of other demands first released earlier this year.

Have a look at the list of demands, especially the “land return” demand (#1) and the usual “and-of-course-we’re-not-to-be-punished” demand (#8).

Twenty minutes into the rally, seven university police officers entered the atrium of Klarman Hall and stood guard near the protestors. At the instruction of lead organizers, students joined arms to form a chain in order to resist interactions with police.

And the kicker: no IDs proferred when asked, and no punishment (bolding is mine, and it’s all bolded because it shows the cowardice of the Cornell administration).

Officers asked protesters to hand over their student identification cards to refer them to the university’s conduct office for potential disciplinary action. None of the protestors followed orders but no arrests were made. 

Have a tweet; this one has three videos and it’s just like the bawling we heard so often last year.

Welcome back! First day of classes, students & activists w/ @cmlcornell were met by 7 @Cornell officers asking for student IDs during a rally calling for the uni to divest in corps supporting Israel in the war against Hamas- atrium @ Klarman Hall- no arrests made. @ithacavoice pic.twitter.com/l1o3kRMvDM

— Judy Lucas (@judy__lucas) August 26, 2024

The unions, by and large all anti-Israel (are there any pro-Israel unions?), were part of the demonstration:

The Coalition for Mutual Liberation (CML), which represents the university’s activist organizations and the group responsible for organizing and maintaining the pro-Palestinian encampment on Cornell’s Arts Quad in April, planned Monday’s demonstration.

They were joined by representatives of the United Auto Workers Local 2300, the union representing about 1,200 university employees, including custodians, cooks and food service workers, who are currently on strike demanding an increase in wages and improved working conditions.

As usual, there’s illegal vandalism:

The morning of the demonstration, graffiti reading “Israel bombs, Cornell pays” and “Blood is on your hands” was found, spray-painted in red, on the front facade of Day Hall, the university’s administrative building. The front door was also shattered.

Cornell’s Vice President for University Relations Joel Malina released a statement on behalf of the university Aug. 26. Malina wrote the administration was “appalled by the graffiti spray painted.”

“Acts of violence, extended occupation of buildings, or property damage (including graffiti) will not be tolerated and will prompt an immediate response from public safety,” Malina wrote. “Cornell Police are conducting a thorough investigation, and those responsible will be subject to suspension and criminal charges.”

Joel Malina is Cornell’s Vice President for University Relations, and if you think that anybody will be suspended or subject to criminal charges, I have some land in Florida to sell you.

Finally, the interim Provost and President sent out an email with dire warnings about what would happen to students who engaged in encampments:

Students involved in encampments would first receive a warning of their violation of the university’s policy. On a second violation, the student would receive a “non-academic temporary suspension.” After a third violation, a student would receive “temporary academic suspension.”

I guess to get a “permanent academic suspension,” you have to shoot someone.

This is only the very beginning. When asked for a comment, the University said bupkes. 

Cornell University has not released a statement or comment regarding the specific demonstration Monday evening during which university police officers were involved.

In response to an email from The Ithaca Voice requesting a statement regarding the protest, a media representative for the university said “We don’t have anything specific regarding yesterday afternoon’s protest.”

Have another tweet with two videos:

Students and activists have entered Klarman Hall from two entrances. I’d guess there are at least 120 people gathered here total— half on the first floor and the other on the second. @cmlcornell @ithacavoice Speakers include Dan Vicente, Director of @UAWregion9. pic.twitter.com/UYx4lBZAgq

— Judy Lucas (@judy__lucas) August 26, 2024

There are more invertebrates in Cornell’s administration than there are in one square meter of the bottom of Cape Town’s Harbour. But there’s one consolation. While Cornell’s administration is demonstrating its spinelessness, I seriously doubt that it will give in to any of the student demands.

h/t: Debi