Space

A new study published in The Astrophysical Journal reveals new evidence for standard gravity breaking down in an idiosyncratic manner at low acceleration. This new study reinforces the evidence for modified gravity that was previously reported in 2023 from an analysis of the orbital motions of gravitationally bound, widely separated (or long-period) binary stars, known as wide binaries.

Humans have dreamed about traveling to other star systems and setting foot on alien worlds for generations. To put it mildly, interstellar exploration is a very daunting task. As we explored in a previous post, it would take between 1000 and 81,000 years for a spacecraft to reach Alpha Centauri using conventional propulsion (or those that are feasible using current technology). On top of that, there are numerous risks when traveling through the interstellar medium (ISM), not all of which are well-understood.

Under the circumstances, gram-scale spacecraft that rely on directed-energy propulsion (aka. lasers) appear to be the only viable option for reaching neighboring stars in this century. Proposed concepts include the Swarming Proxima Centauri, a collaborative effort between Space Initiatives Inc. and the Initiative for Interstellar Studies (i4is) led by Space Initiative's chief scientist Marshall Eubanks. The concept was recently selected for Phase I development as part of this year's NASA Innovative Advanced Concepts (NIAC) program.

An international team of researchers led by Dr. Mungo Frost from the SLAC research center in California has gained new insights into the formation of diamond rain on icy planets such as Neptune and Uranus, using the X-ray laser European XFEL in Schenefeld. The results also provide clues to the formation of the complex magnetic fields of these planets.

In earlier work on X-ray lasers, scientists discovered that diamonds should form from carbon compounds in the interior of the large gas planets because of the high pressure prevailing there. These would then sink further into the interior of the planets as a rain of precious stones from the higher layers.

A new experiment at the European XFEL has now shown that the formation of diamonds from carbon compounds already starts at lower pressures and temperatures than assumed. For the gas planets, this means that diamond rain already forms at a lower depth than thought, and could thus have a stronger influence on the formation of the magnetic fields.

In addition, diamond rain would also be possible on gas planets that are smaller than Neptune and Uranus and are called "mini-Neptunes." Such planets do not exist in our solar system, but they do occur as exoplanets outside of it.

After a flawless launch to orbit, the privately built robotic Peregrine lander is unlikely to reach the lunar surface because of a failure in its propulsion system.

The origin of Earth and the solar system inspires scientists and the public alike. By studying the present state of our home planet and other objects in the solar system, researchers have developed a detailed picture of the conditions when they evolved from a disk made of dust and gas surrounding the infant sun some 4.5 billion years ago.

With the breathtaking progress made in star and planet formation research aiming at far-away celestial objects, we can now investigate the conditions in environments around young stars and compare them to the ones derived for the early solar system. Using the European Southern Observatory's (ESO) Very Large Telescope Interferometer (VLTI), an international team of researchers led by József Varga from the Konkoly Observatory in Budapest, Hungary, did just that. They observed the planet-forming disk of the young star HD 144432, approximately 500 light-years away.

"When studying the dust distribution in the disk's innermost region, we detected for the first time a complex structure in which dust piles up in three concentric rings in such an environment," says Roy van Boekel. He is a scientist at the Max Planck Institute for Astronomy (MPIA) in Heidelberg, Germany, and a co-author of the underlying research article to appear in the journal Astronomy & Astrophysics.

Just a couple more hours until the first launch of ULA's new Vulcan Centaur rocket!

Launch window opens at 2024-01-08 07:18 UTC.

Launch thread with more info has been posted over at [email protected]: ULA Vulcan Cert-1 launch thread!

Searching for liquid water on exoplanets is the key to finding life among the stars, and now, scientists have proposed a new strategy that might improve the chances of finding it.

In the new study, published Dec. 28 in the journal Nature Astronomy, researchers hypothesized that if the atmosphere of an exoplanet has less CO2 than its neighbors, there may be vast quantities of water on its surface — or even life.

A recent study published in the Astrophysical Journal Letters investigates the potential existence of Mars-sized free-floating planets (FFPs)—also known as rogue planets, starless planets, and wandering planets—that could have been captured by our sun's gravity long ago and orbit in the outer solar system approximately 1,400 astronomical units (AU) from the sun. For context, the farthest known planetary body in the solar system is Pluto, which orbits approximately 39 AU from the sun, and is also part of the Kuiper Belt, which scientists estimate extends as far out as 1,000 AU from the sun.

A spectacular year for stargazers is ahead. From the Quadrantid meteor shower in January to the opposition of Jupiter in December, there will be plenty of opportunities to witness the universe's wonders. Highlights of the year include a rare total solar eclipse seen from North America, a moonless Perseid meteor shower and two comets that will shine so bright they may be visible to the naked eye, making 2024 a year not to be missed for sky-watchers. While many of these events are visible with the naked eye, investing now in a good beginner telescope can greatly enhance your experience.

Here are some dates for this year's stargazing diary.

cross-posted from: https://lemm.ee/post/19422551

"In a new article published in Nature Communications, a team centered at the University of Helsinki provided a first-ever quantitative estimate for the likelihood of quark-matter cores inside massive neutron stars. They showed that, based on current astrophysical observations, quark matter is almost inevitable in the most massive neutron stars: a quantitative estimate that the team extracted placed the likelihood in the range of 80–90%."

edit: found this research just today on nucleon liquid Vs quark liquid - very interesting and very much related to this original post.

A large international team of astronomers and astrophysicists has found evidence showing that the Small Magellanic Cloud is not a single galaxy—it is actually two, one behind the other. The group has written a paper describing their work and posted it to the arXiv preprint server.

The Magellanic Clouds have for many years been known as two irregular dwarf galaxies that can be seen as appearing very close to one another in the southern celestial hemisphere. They have also been named individually as the Large and Small Magellanic Clouds, based on their sizes. In the late 1980s, some evidence arose suggesting that the Small Magellanic Cloud (SMC) was not one, but two dwarf galaxies. In this new effort, the researchers have found more evidence, showing that the SMC is indeed two small dwarf galaxies.

T-45 minutes until Firefly's launch of Lockheed Martin's Electronically Steerable Antenna demonstration.

Launch thread has been posted over on [email protected]: https://sh.itjust.works/post/11295530

I am posting updates there. Come join us in that thread!

Astronomers watched 35 explosive outbursts from a rare repeating "fast radio burst" (FRB) as it shifted in frequency like a "cosmic slide whistle," blinking in a puzzling pattern never seen before.

FRBs are millisecond-long flashes of light from beyond the Milky Way that are capable of producing as much energy in a few seconds as the sun does in a year. FRBs are believed to come from powerful objects like neutron stars with intense magnetic fields  —  also called magnetars  —  or from cataclysmic events like stellar collisions or the collapse of neutron stars to form black holes. Complicating the FRB picture, a few FRBs are "repeaters" that flash from the same spot in the sky more than once, while the majority burst once and then vanish.

I can't get enough JWST images

This mission marks New Shepard’s return to flight after the failure during NS-23 in September 2022.

Launch thread has been posted over on [email protected]: https://sh.itjust.works/post/11203171

I will be posting updates there. Come join us in that thread!

The James Webb Space Telescope (JWST) is already making great strides in helping us to unravel the mysteries of the universe. Earlier this year, hundreds of rogue planets were discovered in the Orion Nebula. The real surprise to this discovery was that 9% of the planets were paired up in wide binary pairs. To understand how this binary planets formed, astronomers simulated various scenarios for their formation.