Lifeboat Foundation

According to a tenet scientists call the cosmological principle, our place in space is in no way exceptional. But recent observations could overturn this long-held assumption.

By Sarah Scoles edited by Lee Billings & Jeanna Bryner

Ever since humans started gazing at the heavens through telescopes, we have discovered, bit by bit, that in celestial terms we’re apparently not so special. Earth was not the center of the universe, it turned out. It wasn’t even the center of the solar system! The solar system, unfortunately, wasn’t the center of the universe either. In fact, there were many star systems fundamentally like it, together making up a galaxy. And, wouldn’t you know, the galaxy wasn’t special but one of many, which all had their own solar systems, which also had planets, some of which presumably host their own ensemble of egoistic creatures with an overinflated sense of cosmic importance.

The first dark comet—a celestial object that looks like an asteroid but moves through space like a comet—was reported less than two years ago. Soon after, another six were found. In a new paper, researchers announce the discovery of seven more, doubling the number of known dark comets, and find that they fall into two distinct populations: larger ones that reside in the outer solar system and smaller ones in the inner solar system, with various other traits that set them apart.

The findings were published on Monday, Dec. 9, in the Proceedings of the National Academy of Sciences.

Scientists got their first inkling that dark comets exist when they noted in a March 2016 study that the trajectory of “asteroid” 2003 RM had moved ever so slightly from its expected orbit. That deviation couldn’t be explained by the typical accelerations of asteroids, like the small acceleration known as the Yarkovsky effect.

It could have huge consequences 😰 Read more.

NASA has been monitoring an anomaly in Earth’s magnetic field, growing 40,000 miles above the planet’s surface between South America and southwest Africa.

Using the X-shooter instrument at ESO’s Very Large Telescope (VLT), German astronomers have detected three new pre-white dwarfs, which turned out to be strongly hydrogen-deficient. The finding was reported in a research paper published December 20 on the pre-print server arXiv.

White dwarfs (WDs) are stellar cores left behind after a star has exhausted its nuclear fuel. Due to their high gravity, they are known to have atmospheres of either pure hydrogen or pure helium. However, a small fraction of WDs shows traces of heavier elements.

Although WDs have a relatively small size, comparable to that of the Earth, they are a few million times more massive than our planet. Pre-white dwarfs (PWDs) are a few times larger and slated to shrink in size, eventually becoming WDs within about a few thousand years.

NASA’s Parker Solar Probe mission has detected magnetic distortions in solar wind, known as switchbacks. To better understand these phenomena, whose origins remain uncertain, a study was conducted by a network of collaborators. This study, published in the journal Astronomy & Astrophysics, reveals that solar jets can create similar disturbances without causing a complete reversal of the magnetic field.

NASA’s Parker Solar Probe mission revealed the presence of switchbacks, sudden and rapid reversals of the magnetic field in the solar wind. These peculiar phenomena, rarely observed near Earth, have captivated the scientific community due to their enigmatic origins. A leading theory suggests that switchbacks originate from solar jets, which are ubiquitous in the lower atmosphere of the sun.

To investigate their origins, a team of researchers from LPP, LPC2E, FSLAC, the University of Dundee and Durham University conducted 3D numerical simulations to replicate plasma behavior in the sun’s atmosphere. These simulations modeled solar jets and studied their propagation in solar wind.

Prof. Zhao Yinghe from the Yunnan Observatories of the Chinese Academy of Sciences, along with collaborators, have conducted a study examining the correlation between the [C II] 158 micron emission and the CO(1−0) line. Their findings were published in The Astrophysical Journal.

Molecular gas (H₂) plays a critical role in star formation, a key factor in the evolution of galaxies. Therefore, measuring the gas content in galaxies is crucial. However, the traditional tracer for H₂ mass, the CO(1−0) line, is challenging to detect in the early universe due to various factors, including lower metal content.

As a result, there is a pressing need for alternative H₂ tracers, especially as more galaxies at high redshifts are being discovered.

A rare black moon, the second new moon of December, will rise over Texas tonight.

There will be no single artificial intelligence model that will rule the universe, neither next year nor next decade.

The Last Question is a short story by Isaac Asimov which details the evolution of humanity and our journey to answering the one question that will determine the fate of the universe.

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