Science & TechnologyS


Microscope 1

'Obelisks': Entirely new class of life has been found in the human digestive system

fecalsample
© Science Photo Library/CanvaSEM of Human Gut Microbiome Fecal Sample
Peering into the jungle of microbes that live within us, researchers have stumbled across what seem to be an entire new class of virus-like objects.

"It's insane," says University of North Carolina cell biologist Mark Peifer, who was not involved in the study, told Elizabeth Pennisi at Science Magazine. "The more we look, the more crazy things we see."

These mysterious bits of genetic material have no detectable sequences or even structural similarities known to any other biological agents.

So Stanford University biologist Ivan Zheludev and colleagues argue their strange discovery may not be viruses at all, but instead an entirely new group of entities that may help bridge the ancient gap between the simplest genetic molecules and more complex viruses.

"Obelisks comprise a class of diverse RNAs that have colonized, and gone unnoticed in, human, and global microbiomes," the researchers write in a preprint paper.

Named after the highly-symmetrical, rod-like structures formed by its twisted lengths of RNA, the Obelisks' genetic sequences are only around 1,000 characters (nucleotides) in size. In fact, this brevity is likely one of the reasons we've failed to notice them previously.

Telescope

Flashback Asteroid watch: NASA monitors trajectories of 5 asteroids nearing Earth

earthasteroid
© buradaki/Stock
NASA's Asteroid Watch dashboard has detected five asteroids approaching Earth closely this month.

The dashboard supplies vital information for each encounter, including the closest approach date, approximate object diameter, relative size, and distance from Earth. The dashboard focuses on the next five Earth approaches, all within 4.6 million miles (7.5 million kilometers or 19.5 times the distance to the moon).

"An object larger than about 150 meters that can approach the Earth to within this distance is termed a potentially hazardous object," the NASA dashboard mentions.

Asteroids making a close approach

On Tuesday, January 23, two asteroids are set for close approaches. The first, named 2024 BA1, approximately the size of a house, will come closest to Earth at a distance of 3,270,000 kilometers.

Simultaneously, another asteroid, 2021 BL3, measuring the size of an airplane, will pass by from a distance of 6,600,000 kilometers.

The NASA dashboard also lists three more asteroids expected to make close Earth approaches later in January.

Einstein

Special Relativity and the Lorentz Equations: errors in Einstein's 1905 paper

Equations
© physicsforums.com
The paper in the title has just been published in Physics Essays 37, January 2024, Alasdair Beal .. ISSN 0836-1398 [print] and 2371-2236 [online].

Special Relativity and the Lorentz Equations: Errors in Einstein's 1905 paper. In 1905 Einstein presented his Special Theory of Relativity and claimed to prove that the Lorentz Transformation equations and time dilation of moving clocks can be deduced from it. In a new paper in Physis Essays 37.1, March 2024, Beal has identified errors in Einstein's calculations which invalidate his conclusions.

Despite the mystique around Einstein and relativity there is no complicated physics in this paper and the mathematical errors identified are at the level of simple algebra. Whilst many authors have discussed the implications of Einstein's theory, which are complex, they have not identified the simple errors in his calculations which are fatal to his analysis.

You can view the paper and also download a PDF copy at Beal's web site, https://anbeal.co.uk/relativity.html ...

Meteor

Airplane-size asteroid will have 'very close encounter' with Earth on Saturday — and you can watch it happen

Asteroid 2024 BJ
© NASA Jet Propulsion Laboratory/CalTechAsteroid 2024 BJ (orbit shown in white) will zoom close past Earth (orbit show in light blue) on Jan. 27.
Asteroid 2024 BJ, which astronomers detected earlier this month, will zoom within 220,000 miles of Earth tomorrow, or closer to us than the average distance to the moon.

An asteroid discovered earlier this month will reach its closest point to Earth on tomorrow (Jan. 27), when it will soar through the sky at a distance closer to us than the moon.

You can watch the airplane-size asteroid as it sails just 220,000 miles (354,000 kilometers) from Earth — more than nine-tenths of the average distance between our planet and the moon — on a Virtual Telescope Project live feed from 12:15 p.m. EST. The flying space rock will reach its closest point to Earth at 12:30 p.m. EST, according to NASA.

Astronomers first detected the up to 121-foot-wide (37 meters) asteroid, dubbed 2024 BJ, on Jan. 17. They documented their discovery the following day, after calculating that the rock will safely soar past our planet without incident.

Brain

Musk's brain chip implanted in first human

Neuralink disk implant
© AFP / NeuralinkElon Musk holds the Neuralink disk implant during a presentation in San Francisco, California, August 28, 2020.
Elon Musk has said his biotech company Neuralink has successfully implanted one of its brain chips in a human for the first time, claiming the recipient is in good condition following the surgery. The firm hopes to create an interface allowing people to control devices using their brain alone.

Musk unveiled the development in a post to his social media site, X (formerly Twitter), on Monday evening, stating that the "first human received an implant from Neuralink yesterday and is recovering well."

Though he offered few other details, the tech mogul added that initial results had shown "promising neuron spike detection," referring to brain cells which send chemical and electrical signals to the rest of the body.

Comment: See also:


Mars

NASA's Perseverance rover may already have found signs of life on Mars, discovery of ancient lake sediments reveals

Mars rover Perseverance
© Image credit: NASA/JPL-CaltechAn artist's depiction of NASA's Mars 2020 rover, Perseverance, storing samples of Martian rocks in tubes for future delivery to Earth. Perseverance will land inside Mars' Jezero Crater on Feb. 18, 2021.
NASA's Perseverance rover has found that Mars' Jezero crater was at one point filled with water, offering a tantalizing hope that it may have already unearthed fossilized life on the planet.

The rover, which first touched down on the crater in February 2021 along with its now-retired helicopter companion Ingenuity, made the discovery using ground-penetrating radar — revealing layers of sediment once belonging to a lake that later dried into a gigantic delta.

The finding raises hopes that, once geological samples Perseverance has collected from the crater return to Earth, researchers may find evidence that ancient life once thrived on the now desiccated Red Planet. The researchers published their findings Jan. 26 in the journal Science Advances.

"From orbit we can see a bunch of different deposits, but we can't tell for sure if what we're seeing is their original state, or if we're seeing the conclusion of a long geological story," lead study author David Paige, a professor of planetary science at UCLA, said in a statement. "To tell how these things formed, we need to see below the surface."

Comment: See also: Did Earth 'Steal' Martian Water?


Galaxy

A galaxy with no dark matter could prove dark matter exists

galaxy NGC 1277 devoid of dark matter.
© NASA / ESA / M. Beasley (IAC)The galaxy NGC 1277, which is believed to be devoid of dark matter.
The galaxy, called NGC 177, is located near the center of the Perseus cluster, 240 million light-years from Earth.

One of the most baffling discoveries of 2023 was that of the galaxy NGC 1277.

In July, an international team of astrophysicists led by the Instituto de Astrofísica de Canarias (IAC) and the University of La Laguna (ULL) announced that they had discovered a massive galaxy with no dark matter.

The discovery, though still not fully understood, challenged the standard model of cosmology, which states that all massive galaxies are primarily composed of dark matter.

In that case, what are we to make of a dark matter-deficient galaxy?

In an interview with IE, study lead Sebastién Comerón explained that he had previously doubted the dark matter hypothesis. Still, the lack of dark matter in NGC 1277 actually strengthened his belief in the existence of the mysterious invisible matter.

Comment: Despite these interesting observations, the 'matter' of dark matter is far from settled.


Moon

Japan's precision moon lander has hit its target, but it appears to be upside-down

Lander
© AXA/Takara Tomy/Sony Group Corporation/Doshisha University via APimage taken by a Lunar Excursion Vehicle 2 (LEV-2) of a robotic moon rover called Smart Lander for Investigating Moon, or SLIM, on the moon.
Japan's space agency said Thursday that its first lunar mission hit the tiny patch of the moon's surface it was aiming for, in a successful demonstration of its pinpoint landing system — although the probe appears to be lying upside-down.

Japan became the fifth country in history to reach the moon when the Smart Lander for Investigating Moon, or SLIM, touched down on the moon early on Saturday. But trouble with the probe's solar batteries made it hard at first to figure out whether the probe landed in the target zone.

While most previous probes have used landing zones about 10 kilometers (six miles) wide, SLIM was aiming at a target of just 100 meters (330 feet). Improved accuracy would give scientists access to more of the moon, since probes could be placed nearer to obstacles.

One of the lander's main engines lost thrust about 50 meters (54 yards) above the moon surface, causing a harder landing than planned.

A pair of autonomous probes released by SLIM before touchtown sent back images of the box-shaped vehicle on the surface, although it appeared to be upside down.

After a few days of data analysis, the Japan Aerospace Exploration Agency, or JAXA determined that the spacecraft landed about 55 meters (60 yards) away from its target, in between two craters near the Shioli crater, a region covered in volcanic rock. But after the landing mishap, the craft's solar panels wound up facing the wrong direction, and it cannot generate power. Officials said there is still hope the probe will be able to recharge when the moon enters its daytime in the coming days.

Beaker

The smallest, tightest knot ever created is just 54 atoms long

molecular knot smallest tightest
© Zhiwen Li, et al.Scientists have broken the record for the smallest and tightest molecular knot
Scientists have broken the record for the smallest and tightest molecular knot, creating a chemical that self-assembles into a knot with the formula [Au6{1,2-C6H4(OCH2CC)2}3{Ph2P(CH2)4PPh2}3]. The makers highlight the six gold atoms at the start by referring to the entire molecule as Au6.

The way a molecule affects others depends not just on the elements it's composed of, but on the shape these take on. Complex molecules can be folded in vast numbers of ways, and sometimes only one of these will produce the desired biological effects. Predicting and controlling such folding is considered one of the hardest problems in science, and one where computers are only just starting to displace humans.

Knots represent the extreme end of this. It's not easy to tie even long thin strands of atoms into knots because you can't just grab the ends like pieces of rope on a sailboat. Finding ways to make molecules knot can help develop humanity's capacity for more practical knotting. Since DNA, RNA, and many proteins knot without human intervention, performing knotting of our own helps us understand these vital molecules' behavior.

Mars

NASA's Ingenuity helicopter mission on Mars ends after damaging a rotor blade

ingenuity helicopter mars rover perseverance
© NASA/JPL - CaltechPerseverance captured an image of Ingenuity on August 2, 2023, the day before the helicopter's 54th flight.
Together, the rover and helicopter spent the past few years exploring Jezero Crater, the site of an ancient lake and river delta on Mars. Scientists are hoping that samples collected by Perseverance, which will be returned to Earth by future missions, could determine whether life ever existed on the red planet.

After completing 72 historic flights on Mars over three years, NASA's Ingenuity helicopter mission has ended.

Originally designed as an experiment, Ingenuity became the first aircraft to operate and fly on another world, lifting off on April 19, 2021.

Imagery and data returned to NASA's Jet Propulsion Laboratory in Pasadena, California, showed that one or more of the chopper's carbon fiber rotor blades was damaged while landing during its final flight this month. The team determined that the helicopter is no longer able to fly, according to the space agency.

Ingenuity, which had traveled to Mars as the Perseverance rover's trusty sidekick, is sitting upright on the surface of the red planet, and mission controllers at NASA's Jet Propulsion Laboratory have been able to maintain communications with the rotorcraft.