Galaxies in the Universe

An image from the Hubble Space Telescope showing hundreds of faraway galaxies. (Image credit: NASA, ESA, CSA, STScI, J. Diego (Instituto de Física de Cantabria, Spain), J. D’Silva (U. Western Australia), A. Koekemoer (STScI), J. Summers & R. Windhorst (ASU), and H. Yan (U. Missouri))



The Milky Way is just a speck in a universe filled with an untold number of galaxies. But if we had to take an educated guess, how many galaxies are in the universe?


That sounds like a simple question, but it's anything but. The first problem is that even with our most powerful telescopes, we can see only a tiny fraction of the universe.


"The observable universe is only that part of the universe from which the light has had time to reach us," astrophysicist Kai Noeske, now outreach officer at the European Space Agency, told Live Science.     
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Time as a Mirage

Time may not be a fundamental element of the universe but rather an illusion emerging from quantum entanglement, a new study suggests.


Time is a thorny problem for physicists; its inconsistent behavior between our best theories of the universe contributes to a deadlock preventing researchers from finding a "theory of everything," or a framework to explain all of the physics in the universe.


But in the new study, researchers suggest they may have found a clue to solving that problem: by making time a consequence of quantum entanglement, the weird connection between two far-apart particles. The team published their findings May 10 in the journal Physical Review A.                            READ MORE...

X-Shaped Structures in Space

This visualization shows C-shaped and reverse-C-shaped plasma bubbles appearing close together in the ionosphere on Oct. 12, 2020, and Dec. 26, 2021, as observed by NASA’s GOLD mission (Image credit: NASA’s Scientific Visualization Studio)




A NASA satellite has spotted unexpected X- and C-shaped structures in Earth’s ionosphere, the layer of electrified gas in the planet’s atmosphere that allows radio signals to travel over long distances.


The ionosphere is an electrified region of Earth's atmosphere that exists because radiation from the sun strikes the atmosphere. Its density increases during the day as its molecules become electrically charged. That's because sunlight causes electrons to break off of atoms and molecules, creating plasma that enables radio signals to travel over long distances. The ionosphere’s density then falls at night — and that's where GOLD comes in.


NASA's Global-scale Observations of the Limb and Disk (GOLD) mission is a geostationary satellite that has been measuring densities and temperatures in Earth's ionosphere since its launch in October 2018. From its geostationary orbit above the western hemisphere, GOLD was recently studying two dense crests of particles in the ionosphere, located north and south of the equator. As night falls, low-density bubbles appear within these crests that can interfere with radio and GPS signals. However, it's not just the wax and wane of sunshine that affects the ionosphere — the atmospheric layer is also sensitive to solar storms and huge volcanic eruptions, after which the crests can merge to form an X shape.               READ MORE...

ANTS Perform Life Saving Operations

 

Florida carpenter ants perform amuptations on nestmates when their legs are injured. 

(Image credit: Bart Zijlstra)



Ants in Florida perform life-saving surgery on their peers, scientists have discovered. They are only the second animal in the world known to do this — along with humans.


The researchers found that Florida carpenter ants (Camponotus floridanus) identify limb wounds on their nestmates, then treat them with either cleaning or amputation.


The team published its findings Tuesday (July 2) in the journal Current Biology.            READ MORE...

Asteroid Larger than Giza Pyramid

The potentially hazardous asteroid 2024 MK will sail between Earth and the moon on Saturday. (Image credit: JUAN GARTNER via Getty Images)



A skyscraper-size asteroid discovered two weeks ago will zoom between Earth and the moon on Saturday (June 29). At its closest approach, the space rock will pass within roughly 184,000 miles (295,000 kilometers) of our planet — about three-quarters the average distance between Earth and the moon.


The asteroid, named 2024 MK, is estimated to measure about 480 feet (146 meters) across, which is greater than the height of a 40-story building or the Great Pyramid of Giza.


During its closest approach, it will be traveling at roughly 21,000 mph (34,000 km/h), according to NASA. Astronomers in South Africa discovered the asteroid on June 16.        READ MORE...

The Early Universe at Cosmic Dawn

The Cosmic Gems is one of the most highly magnified objects in space, thanks to a phenomenon called gravitational lensing. (Image credit: ESA/Webb, NASA & CSA, L. Bradley (STScI), A. Adamo (Stockholm University) and the Cosmic Spring collaboration)





Astronomers using the James Webb Space Telescope have observed five extremely dense proto-globular clusters along a hair-thin arc of glittering stars. The discovery could help them understand how the earliest galaxies formed.

The James Webb Space Telescope (JWST) has discovered what could be the earliest star clusters in the universe.  JWST spotted the five proto-globular clusters — swarms of millions of stars bound together by gravity — inside the Cosmic Gems arc, a galaxy that formed just 460 million years after the Big Bang.


The Cosmic Gems arc gets its name from its appearance: When seen from our solar system, the star-studded galaxy looks like a hair-thin crescent due to the powerful gravitational influence of a foreground galaxy, which magnifies and distorts the distant galaxy's appearance.     READ MORE...

A Force More Powerful than Gravity

"Today, the Earth's liquid core is still a terpsichorean frenzy of electric currents, which generate a magnetic field." (Image credit: Shutterstock)






The image of an atom, with electrons swarming around a central nucleus bulging with protons and neutrons, is as iconic in our perception of science as the DNA helix or the rings of Saturn. But however much we scratch the surface of these scientific fundamentals, we can go even deeper, focusing that microscope further and discovering even more forces that govern our world.


In his new book "CHARGE: Why Does Gravity Rule?", theoretical physicist Frank Close explores the fundamental forces that govern our world, posing questions along the way that seek to explain how the delicate balance of positive and negative charges paved the way for gravity to shape our universe.


In this except, he explains how magnetism, the most tangible fundamental forces, was discovered, where it comes from and how it got its name.        READ MORE...

Mistreating Artificial Intelligence

How can we truly know if AI is sentient? We do not yet fully understand the nature of human consciousness, so we cannot discount the possibility that today's AI is indeed sentient — and that we are mistreating it to potentially grave consequences.

Artificial intelligence (AI) is becoming increasingly ubiquitous and is improving at an unprecedented pace.

Now we are edging closer to achieving artificial general intelligence (AGI) — where AI is smarter than humans across multiple disciplines and can reason generally — which scientists and experts predict could happen as soon as the next few years. We may already be seeing early signs of progress, too, with Claude 3 Opus stunning researchers with its apparent self-awareness.

But there are risks in embracing any new technology, especially one that we do not fully understand. While AI could be a powerful personal assistant, for example, it could also represent a threat to our livelihoods and even our lives.     READ MORE...

2,000 Year Old Carving

Brazilian archaeologists have discovered a vast number of 2,000-year-old rock carvings that depict human footprints, celestial-body-like figures, and representations of animals, such as deer and wild pigs.


The discovery was made during three expeditions between 2022 and 2023 in Jalapão State Park, located in the state of Tocantins. Researchers with Brazil's National Institute of Historic and Artistic Heritage (IPHAN) identified 16 precolonial archaeological sites, all located on rocky cliffs close to each other.

"This proximity suggests a possible connection between the sites and clarifies settlement patterns of the ancient communities that inhabited the region," Rômulo Macêdo, the archaeologist who led the work, told Live Science via Whatsapp.     READ MORE...

Humans Wearing Clothes

Clothes don't survive the way artifacts made of stone, bone and other hard materials do, so scientists have to get creative to answer this question.


As early humans evolved from ape-like ancestors, they came down from the trees, began to walk upright and lost their fur. But without fur, our ancestors would have been exposed to the elements. They would have needed clothing for protection.


So when did humans start wearing clothes?


This is a tricky question, because clothes don't survive the way artifacts made of stone, bone and other hard materials do. Instead, scientists have to get creative. The evidence used to answer this question comes from a few main sources, including bones bearing evidence of skinning, sewing needles and awls, and lice.  READ MORE...

Oxytocin Influences Animal Behavior

Oxytocin (OXT) is a hormone that is known for its effects on psychological well-being and emotional bonding in animals. Interestingly, research has shown that this natural chemical in the brain plays a crucial role in other cognitive processes as well, including learning and memory. 

Now, scientists may have discovered exactly how OXT influences memory in animals by studying "OXT neurons" that contain OXT receptors and function differently based on the availability of the chemical in the brain.  READ MORE...

A Cosmological Mystery

Astronomers have discovered a cosmic "ring" that's so enormous, it defies explanation with our best theories of the universe.

Named the Big Ring, the gigantic spiral of galaxies and galaxy clusters is 1.3 billion light-years wide and has a circumference of 4 billion light-years, making it one of the largest objects ever seen.

Because the Big Ring is so far from Earth — 9 billion light-years away — its light is too dim to be viewed with the naked eye. But if it were brighter, it would appear 15 times the size of the full moon in the night sky.  READ MORE...

First Wooden Satellite

NASA and the Japan Aerospace Exploration Agency (JAXA) are planning to launch the world's first wooden satellite into space in a bid to make spaceflight more sustainable.


LignoSat, a coffee mug-size satellite made from magnolia wood, is set to launch into Earth's orbit by summer 2024, according to the space agencies.

Wood doesn't burn or rot in the lifeless vacuum of space, but it will incinerate into a fine ash upon reentry into Earth's atmosphere — making it a surprisingly useful, biodegradable material for future satellites. After successfully testing their wood samples aboard the International Space Station (ISS) earlier this year, the scientists believe the test satellite is fit for launch.    READ MORE...

World's Largest Underwater Telescope in China

Scientists in China are building the world's largest "ghost particle" detector 11,500 feet (3,500 meters) beneath the surface of the ocean.

The Tropical Deep-sea Neutrino Telescope (TRIDENT) — called Hai ling or "Ocean Bell" in Chinese — will be anchored to the seabed of the Western Pacific Ocean. Upon completion in 2030, it will scan for rare flashes of light made by elusive particles as they briefly become tangible in the ocean depths.

Every second, about 100 billion ghost particles, called neutrinos, pass through each square centimeter of your body. And yet, true to their spooky nickname, neutrinos' nonexistent electrical charge and almost-zero mass mean they barely interact with other types of matter.

But by slowing neutrinos down, physicists can trace some of the particles' origins billions of light-years away to ancient, cataclysmic stellar explosions and galactic collisions.

That's where the ocean bell comes in.

"Using Earth as a shield, TRIDENT will detect neutrinos penetrating from the opposite side of the planet," Xu Donglian, the project's chief scientist, told journalists at a news conference Oct. 10. "As TRIDENT is near the equator, it can receive neutrinos coming from all directions with the rotation of the Earth, enabling all-sky observation without any blind spots."

Neutrinos are everywhere — they are second only to photons as the most abundant subatomic particles in the universe and are produced in the nuclear fire of stars, in enormous supernova explosions, in cosmic rays and radioactive decay, and in particle accelerators and nuclear reactors on Earth..

Despite their ubiquity, their minimal interactions with other matter make neutrinos incredibly difficult to detect. They were first discovered zipping out of a nuclear reactor in 1956, and many neutrino-detection experiments have spotted the steady bombardment of the particles sent to us from the sun; but this cascade masks rarer neutrinos produced when cosmic rays, whose sources remain mysterious, strike Earth's atmosphere.  READ MORE...

Elusive Planet Nine

An artist's impression of what Planet Nine might look like at the edge of the solar system. (Image credit: Shutterstock)



The elusive Planet Nine, which is theorized to be lurking somewhere in the outer reaches of the solar system, may not be a planet after all, a new study suggests. Instead, what we assumed to be a massive object could be evidence that gravity doesn't work like we thought it does. But the new theory doesn't sit well with everyone.


The Planet Nine hypothesis, first proposed in 2016, argues that the unusual orbits of objects in the Kuiper Belt beyond Neptune, which seem to be being pulled away from the sun, can be explained by the presence of an undiscovered ninth planet up to 10 times more massive than Earth. Astronomers have been looking for Planet Nine ever since. However, despite searching almost half of the night sky, they have so far come up empty-handed.

In the new study, published Sept. 22 in The Astronomical Journal, researchers proposed another explanation for the gravitational anomalies observed in the outer solar system — that there aren't any anomalies. Instead, the team shows that the inconsistencies disappear completely when applying an alternative concept of gravity known as modified Newtonian dynamics (MOND).   READ MORE...

An Ocean of Water Under An Ocean of Water

Ancient volcanic rocks were eroded and stored a sea's worth of water in Earth's crust as they became buried. (Image credit: James O'Neil via Getty Images)



Porous rock that formed during one of Earth's biggest volcanic eruptions absorbed so much water as it eroded that it created a huge reservoir over the eons, now buried deep in Earth's crust.

A massive water reservoir is hidden deep beneath the ocean floor off the coast of New Zealand — and it may explain why the region experiences slow-motion earthquakes, scientists have found.


A sea's worth of water became locked inside volcanic rocks that formed 120 million to 125 million years ago during the early Cretaceous, when a lava plume the size of the U.S. burst through Earth's crust and solidified into a vast plateau, researchers said in a statement. Thick layers of sediment have since blanketed these rocks and buried any trace of their explosive past 2 miles (3 kilometers) below the Pacific Ocean seabed.

The researchers mapped a fault line along the east coast of New Zealand's North Island and found that these ancient rocks were abnormally "wet," with water making up nearly half the volume of cores drilled up from the ocean floor.

"Normal ocean crust, once it gets to be about seven or 10 million years old, should contain much less water," study lead author Andrew Gase, a marine geophysicist and seismologist who conducted the research while at the University of Texas Institute for Geophysics (UTIG), said in the statement.


Shallow seas that surrounded the ancient volcanic plateau may have eroded the rocks into a porous honeycomb, which sponged up water and stored it like an aquifer, according to the statement. This water-logged terrain slowly transformed over the eons, absorbing more water as the rocks were ground into clay and became buried.  READ MORE...

New Section of Universe Discovered

Astronomers may have detected a dozen large objects lurking beyond the Kuiper Belt at the edge of our solar system, suggesting there could be another equally massive, "second Kuiper Belt" hiding beyond the orbit of Pluto.

Researchers may have detected a dozen new, large objects beyond the Kuiper Belt, which suggests that there is lots more stuff in the solar system than we realized. It could even hint that there is a "second Kuiper Belt" further out toward the edge of our stellar neighborhood, Science.org reported.

The sun's influence reaches much further out into space than the eight planets that orbit around it. Beyond Neptune, the solar system stretches out to around 100 astronomical units (AU), which is 100 times the distance between Earth and the sun. For context, the most distant planet from the sun, Neptune, is roughly 30 AU from our home star.

Beyond the edge of the solar system, or heliopause, lies the Oort Cloud — a reservoir of comets and asteroids that are loosely contained by the sun's gravity — that stretches to at least 1,000 AU from the sun, and likely even further.

But a majority of the largest known asteroids, comets and other large objects that lie beyond Neptune's orbit are contained within the Kuiper Belt, which stretches between 30 and 50 AU from the sun. 

Famous residents of the Kuiper Belt include the dwarf planet Pluto and the double-lobed object Arrokoth — the most distant object visited by a spacecraft. Planet Nine, if it exists, would also lurk somewhere within the Kuiper Belt. 

Until now, very few massive objects in the solar system have been found beyond the Kuiper Belt.  READ MORE...

Matter in the Universe

Most matter in the universe cannot be seen — but its influence on the largest structures in space can.

Astronomers estimate that roughly 85% of all the matter in the universe is dark matter, meaning only 15% of all matter is normal matter. Accounting for dark energy, the name astronomers give to the accelerated expansion of the universe, dark matter makes up roughly 27% of all the mass energy in the cosmos, according to CERN (the European Organization for Nuclear Research).

Astronomers have a variety of tools to measure the total amount of matter in the universe and compare that to the amount of "normal" (also called "baryonic") matter. The simplest technique is to compare two measurements.

The first measurement is the total amount of light emitted by a large structure, like a galaxy, which astronomers can use to infer that object's mass. The second measurement is the estimated amount of gravity needed to hold the large structure together. 

When astronomers compare these measurements on galaxies and clusters throughout the universe, they get the same result: There simply isn't enough normal, light-emitting matter to account for the amount of gravitational force needed to hold those objects together.

Thus, there must be some form of matter that is not emitting light: dark matter.

Different galaxies have different proportions of dark matter to normal matter. Some galaxies contain almost no dark matter, while others are nearly devoid of normal matter. But measurement after measurement gives the same average result: Roughly 85% of the matter in the universe does not emit or interact with light.  READ MORE...

The Mystery of Planet Formation

Until the 1950s, ideas about planet formation were mosly dismissed as fanciful and few astronomers took the question seriously. (Image credit: Andrzej Wojcicki/Getty Images)



We've only got to grips with how the planets in our solar system formed in the last 100 years. In the extract below from "What's Gotten Into You" (HarperCollins, 2023), Dan Levitt looks at the Soviet mathematician who spent a decade working on a problem that most astronomers had given up on, and — when he finally solved it — was met with disinterest and skepticism.

Over 4.8 billion years ago, the atoms that would create us sailed in great clouds of gas and dust, toward… well, nothing. There was no solar system, no planets, no Earth. In fact, for a long time, scientists could not explain how our solid planet, not to mention one so hospitable to life, appeared at all. 

How was our now-rocky planet conjured, like magic, out of an ethereal cloud of gas and dust? How and when did Earth become so welcoming to life? And what travails were our molecules forced to brave until life could evolve?

Scientists would learn that our atoms could finally create life only after they endured wrenching collisions, meltdowns, and bombardments — catastrophes that beggar any destruction ever witnessed by humankind.  READ MORE...

TWENTY-TWO People Needed to Colonize Mars

Researchers estimated that as few as 22 people would be needed to sustain a colony on Mars. But there are lots of caveats, and the new study largely misses the point of colonizing the Red Planet in the first place, experts say.

Only 22 people are needed to create a colony on Mars, an optimistic new study suggests. However, not everyone agrees, and some experts think many more people would be needed to create a lasting human presence on the Red Planet.

In the study, which was uploaded to the pre-print database arXiv on Aug. 11 and has not been peer-reviewed, researchers used a computer program, known as an agent-based model (ABM), to predict how many people would be needed to sustain a colony on Mars. ABMs simulate how well groups react to challenging scenarios based on their personality types.

The model looked at four personality types: agreeables, who are not very competitive or aggressive; socials, who are extroverted and do well in social settings; reactives, who struggle to deal with changes to routine; and neurotics, who are highly competitive and aggressive. The model then varied the number of each type when doing key tasks such as Martian mining and farming.

The researchers found that iIf most people were agreeables or socials, just 22 people could sustain a colony. With more neurotics and reactives, larger groups were needed to succeed.

Limiting the size of the first Martian colonies will be very important, because the more people and equipment that are needed, the more expensive it will be.    READ MORE...