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I noticed last week that the followers of my Twitter account had dropped by several hundred, and then I realized that a lot of people are going to the alternative site Bluesky, presumably because they don’t like Elon Musk because he gave a lot of dosh to Trump (and now has a job in the Trump Administration).

Matthew went from “X” to Bluesky a while back, and has been telling me to move as well. He said this:

People aren’t leaving (just) because they hate Musk – the site [X] doesn’t work. Posts aren’t seen, even if you follow people your timeline gets swamped with blue tick reply guy crap. To see what people post you have to go onto their timeline. And fewer and fewer people are there. You have 40,000 followers [JAC: it’s 36,400] – how many interactions with your tweets? How many of those followers are either a) human or b) active? And – though this isn’t why you use it – the fun component [like the tweet he sent about fat cheetah cubs]) has disappeared from X completely. The Guardian has stopped posting there. User numbers are dropping. Not a useful or fun place to be any more.

Yes, there appear to be advantages of Bluesky, which seem to include these:

1. Everybody seems to be going there, though I haven’t done any systematic checking, as I don’t formally follow anyone on Twitter
2. You can directly embed the posts (they are apparently called “skeets”) into my website without going through the complicated process of embedding Tweets
3. It appears to  have more fun stuff on it, though I like a mixture of fun and serious stuff (e.g., animals and politics)

The downsides seem less important, but include two:

1. How do I get all the people who follow me now to go there? I suppose by telling them on X.
2. I am old and lazy, and it takes a bit of effort—though not much—to open an account.

I don’t particularly feel compelled to leave X just because Elon Musk runs it, as I have no strong feelings about that, but I suppose I’ll move after I check Bluesky. But I wonder about readers’ experience with these two cites. Please give your take below (not advice on whether to move, but the relative advantages of the two sites). Which site do you use or occupy? Are there any other advantages, issues or features that I don’t know about?

Eric Bailey, Public domain, via Wikimedia Commons

Rates of near-sightedness are rising all over the world. But solutions to the epidemic are coming into focus and could be simpler than you think

Selection for bigger tomatoes has made the fruits less sweet, but now it has been shown that gene editing can make them sweeter without decreasing yields

Researchers mapped Earth’s ionosphere, part of the upper atmosphere, using signal data from 40 million phones – a method that could improve GPS accuracy and help track space weather

Palaeontologists have pieced together the brain structure of a bird that lived 80 million years ago named Navaornis hestiae, thanks to a remarkably well-preserved fossil  

There is a region of the sky where astronomers fear to look. Filled with dark clouds of dust, it hides an unseen mass. A mass so large it is pulling the Milky Way and other galaxies toward it…

Okay, maybe that’s overdramatic, but it is true. The region is known as the Zone of Avoidance, and it happens to be in the general direction of the galactic center. Our view of the Universe isn’t as perfect as we’d like. The Sun is located within the galactic plane of the Milky Way, about 30,000 light-years from its center. So if we look to the north or south of the galactic plane, we get a pretty normal view of the cosmos. We can peer deep into the sky and see distant galaxies. But if we look toward the galactic center, we don’t have a clear view. Instead, we see a bunch of stars, gas, and dust. This is fine if you want to study stars, gas, and dust, but it means our view of the distant Universe is obscured in that direction. So if you want to make an unbiased view of the cosmos, you avoid that region, hence the term.

It’s also true that we’re being pulled in that direction. There happens to be a supercluster of galaxies that way, called the Great Attractor. We can map it out a bit by studying the relative motion of nearby galaxies, and we can observe X-rays from the supercluster, so we know it’s out there. But with all the gas and dust in the Zone of Avoidance, we can’t study it in the optical. One thing we know so far is that the Great Attractor actually consists of multiple clusters. The closest one is known as the Norma cluster, while a larger and more distant one is called the Vela supercluster. Still, there is much we don’t know about the region.

Fortunately, radio light can penetrate the dust of the Zone, so radio astronomers have tried to map the region. One downside is that radio telescopes often don’t have a large field of view, so it’s difficult to map the region. But a new work is making progress.

Observed galaxies within the Vela supercluster. Credit: Sambatriniaina H. A. Rajohnson, et al

The new study uses data from the MeerKAT array telescope in South Africa. MeerKAT is particularly sensitive to the radio emissions of neutral hydrogen, known as the HI or [21-centimeter line.](https://briankoberlein.com/blog/dark-line/) Since hydrogen is so abundant in the Universe, the distribution of hydrogen tells us the distribution of galaxies and clusters. The study mapped the region of the Zone in the direction of the Vela supercluster with enough resolution to distinguish individual pockets of neutral hydrogen, each surrounding a galaxy. In this way, the team was able to discover 719 galaxies within the Vela cluster. Less than a third of them had been known previously.

This was just the first detailed survey of the Vela supercluster by MeerKAT, and it shows the real power of this relatively new observatory. Future studies should give us an even better understanding of the zone astronomers so often avoid.

Reference: Sambatriniaina H. A. Rajohnson, et al. “Revealing hidden structures in the Zone of Avoidance — a blind MeerKAT HI Survey of the Vela Supercluster.” arXiv preprint arXiv:2411.07084 (2024).

The post Astronomers Defy the Zone of Avoidance to Find Hundreds of New Galaxies appeared first on Universe Today.

In today’s Jesus and Mo strip, called “reason,” the barmaid suggests that both Jesus and Mo are going to hell. I am puzzled; why would they? They are prophets and, in Jesus’s case, the son of God/God. 

Today we have photos from South Africa taken by reader Phil Frymire on a recent trip. Phil’s captions and IDs are indented, and you can enlarge his pictures by clicking on them.

Here are some more photos from an August trip to Timbavati and Mala Mala in South Africa that occurred at the same time as our host’s visit. I previously submitted some leopards, lions, elephants and rhinos. Rounding out the Big Five, here are some African buffalo (Syncerus caffer) along with some spotted hyenas (Crocuta Crocuta), Burchell’s zebras (Equus quagga burchellii) and Northern giraffes (Giraffa camelopardalis).

A resting buffalo:

A herd of buffalo. The male in the foreground has an impressive “boss” (the area where the horns grow together in the middle):

A “dagga boy” as Jerry’s guide Dan called them. Our guide Mike called them “retired”. These are old males that no longer travel with the herds. They will likely be taken by lions (but see the photo below). This one is accompanied by a red-billed oxpecker (Buphagus erythroryncha):

When we first encountered these lions at Mala Mala, they were walking with their left sides facing us. One of the females was limping pitifully. After we drove around for a better look, it became obvious why she was struggling. If you look carefully at the female on the right you will see a gaping, horrific wound on her right front leg running from the shoulder to the elbow. She never emerged from the bushes while we observed her so I couldn’t get a clear photo. Mike was very confident that the injury was caused by a buffalo horn. Predators fight for a meal, but prey fight for their life. Predators don’t always emerge from the fracas unscathed. Revenge of a dagga boy?:

Profile of a spotted hyena:

The same hyena intently staring at us:

Hyena with a black-backed jackal (Lupulella mesomelas) in the foreground:

The same hyena literally eating bone. The crushing sounds were very impressive:

A beautiful zebra:

Posing above a waterhole:

Why do zebras have stripes? Jerry mentioned in one of his posts that the scientific evidence supports the hypothesis that the stripes deter biting flies. I asked our guide Mike what he thought. He favored the idea that the stripes break up the body outline and confuse predators. He didn’t cite any scientific papers, but he did cite this view of a mother and foal:

Another mother and foal at a waterhole:

Four male giraffes:

Frontal view of a male showing the thick ossicones that they use in combat with other males:

Profile of a giraffe with an oxpecker on its neck:

When physicians spread medical misinformation, the potential harm to health is far greater than their direct patient care. And yet, in a recent study, medical boards rarely discipline physicians for spreading misinformation. The JAMA article looked at 3128 medical board disciplinary proceedings involving physicians. Spreading misinformation to the community was the least common reason, at 0.1%. Direct patient misinformation and inappropriate advertising […]

The post Physician Misinformation first appeared on Science-Based Medicine.

Global carbon emissions from fossil fuels have reached a record high in 2024, according to new research.

Completely artificial proteins that produce bioluminescence can serve as a non-invasive method for bioimaging, diagnostics, drug discovery, and more.

A team of archaeologists has excavated the earliest known ancient Maya salt works in southern Belize.

A new study has uncovered important behavior in the flow of electric current through quantum superconductors, potentially advancing the development of future technologies like quantum computing.

A new study has uncovered important behavior in the flow of electric current through quantum superconductors, potentially advancing the development of future technologies like quantum computing.

These miniature immune system models -- known as human immune organoids -- mimic the real-life environment where immune cells learn to recognize and attack harmful invaders and respond to vaccines. Not only are these organoids powerful new tools for studying and observing immune function in cancer, their use is likely to accelerate vaccine development, better predict disease treatment response for patients, and even speed up clinical trials.

The chances of intelligent life emerging in our Universe -- and in any hypothetical ones beyond it -- can be estimated by a new theoretical model which has echoes of the famous Drake Equation. This was the formula that American astronomer Dr Frank Drake came up with in the 1960s to calculate the number of detectable extraterrestrial civilizations in our Milky Way galaxy. More than 60 years on, astrophysicists have produced a different model which instead focuses on the conditions created by the acceleration of the Universe's expansion and the amount of stars formed.

Scientists point out that a coherent approach to understanding the threats posed by artificial intelligence is still elusive. They call for a complex systems perspective to better assess and mitigate these risks, particularly in light of long-term uncertainties and complex interactions between AI and society.

An annual accounting of CO2 emissions from burning fossil fuels and land use change finds no sign emissions will peak this year

Eurasian reed warblers don’t just get a sense of direction from Earth’s magnetic field – they can also calculate their coordinates on a mental map

Filmmakers love New Zealand. Its landscapes evoke other worlds, which explains why so much of The Lord of the Rings was filmed there. The country has everything from long, subtropical sandy beaches to active volcanoes.

The country’s otherworldliness extends into its atmosphere, where a cloud nicknamed the “Taieri Pet” forms when conditions are right.

The Taieri Pet is a lenticular cloud, a stationary type of cloud that forms in certain circumstances. They form in the troposphere when the wind blows over an obstacle, typically a mountain range. There are three types: altocumulus standing lenticular (ACSL), stratocumulus standing lenticular (SCSL), and cirrocumulus standing lenticular (CCSL). Each type forms at a different altitude.

When the wind is forced to move up and over an obstacle, it creates a lower-pressure zone on the leeward side. As the wind moves, it creates standing waves. If conditions are right, these waves become visible when the moisture condenses.

The Taieri Pet forms over New Zealand’s Rock and Pillar Range in the Strath-Taieri region of Otago on New Zealand’s South Island.

The Otago region on New Zealand’s South Island is home to the Taieri Pet. Image Credit: Peetel, (Creative Commons Attribution-Share Alike 4.0 International.)

The cloud is a common feature near the town of Middlemarch. It’s mentioned in newspapers as far back as the 1890s. Locals sometimes took Taieri Pet’s appearance as a signal that a storm was coming.

This page is from the Otago Witness, Issue 2226, 29 October 1896. It describes the Taieri Pet as “our old prognosticator,” because it forms before a wind storm. Image Credit: No Known Copyright.

The Operational Land Image (OLI) on Landsat 8 captured this stunning image of the Taieri Pet in September. Landsat 8 follows a polar orbit that allows it to observe the entire surface of the Earth every 16 days.

This zoomed-in image shows the cloud and the surface in more detail. The image shows the Macraes Mine, New Zealand’s largest gold mine. Image Credit: NASA/Lauren Dauphin; USGS

The Landsat satellites have been monitoring Earth for over 50 years from their orbit 705 km above us. The images and data are widely used by scientists, but they’re also beautiful portraits of our extraordinary, once-in-a-solar-system planet.

Anybody can enjoy the Landsat galleries, found here.

The post An Otherworldly Cloud Over New Zealand appeared first on Universe Today.