Space

...The reason physicists have been skeptical about wormholes comes down to a problem with energy. To hold the throat of a wormhole open, you would need something called exotic matter. In physics, ordinary matter (stars, gas, you, your coffee) always has a positive energy density which corresponds to positive mass. Exotic matter would have negative energy density, essentially “negative mass.” We have never observed anything like that in nature. Most wormhole solutions that physicists have found over the decades require this exotic matter to exist, which is why wormholes have stayed firmly in the category of “mathematically possible but physically unlikely.” Today’s paper offers a way around this problem.

Instead of trying to prop open a wormhole with exotic matter, the authors add two extra physical fields to Einstein’s equations alongside gravity. The first is an electromagnetic field, the same electric and magnetic fields you encounter in introductory physics. This wormhole carries both electric and magnetic charge. The second is something called a dilaton...

Why should we care about the dilaton? Because it is not something the authors invented for convenience. It shows up naturally in several theories that physicists take seriously as candidates for deeper laws of nature. Superstring theory, which attempts to unify all fundamental forces, predicts a dilaton. So does Kaluza-Klein theory, which tries to explain electromagnetism as a consequence of a hidden extra dimension of space. And Brans-Dicke theory includes one too. If any of these theories are correct, the dilaton exists, and the kind of wormhole described in this paper becomes a natural prediction of Einstein’s equations...

"Around the Moon and back. Watch the Artemis II astronauts come home.

NASA's Artemis II mission is splashing down in the Pacific Ocean at about 8:07 p.m. EDT on Friday, April 10 (0007 UTC April 11).

Four astronauts — three from NASA and one from the CSA (Canadian Space Agency) — make up the Artemis II crew: • NASA astronaut Reid Wiseman, Artemis II commander • NASA astronaut Victor Glover, Artemis II pilot • NASA astronaut Christina Koch, Artemis II mission specialist • Canadian Space Agency (CSA) astronaut Jeremy Hansen, Artemis II mission specialist

The Artemis II astronauts launched on April 1 for a journey of ten days that took them farther than any humans have traveled from Earth. On their Orion spacecraft, named Integrity, they flew around the Moon, making observations which will help enhance scientific understanding.

Artemis II is the first crewed flight test of NASA's Space Launch System rocket and Orion spacecraft, testing the technologies we'll need for long-term lunar exploration and human missions to Mars.

Read the latest Artemis II mission updates: https://www.nasa.gov/b... Learn more about the mission and why we're going: https://www.nasa.gov/m...

Credit: NASA"

Follow current live events of Artemis II Mission until broadcast for landing begins.

https://www.youtube.com/live/m3kR2KK8TEs

Description:

Track NASA's Artemis II Orion spacecraft live as it travels to the Moon and back. Real-time 2D map with position, speed, distance from Earth and Moon, crew info, mission elapsed time, and trajectory replay for all Artemis missions. Free-return trajectory explained.

Bonus eclipse photo! More pics are being uploaded here: https://images.nasa.gov/

For 3.8 billion years, the breathtaking view of the Orientale basin has lain hidden towards the far side of the moon.

Thought to have been formed after a 40-mile-wide asteroid collided with the Moon, sending molten rock miles into space, the 600-mile crater has until this weekend only been photographed by robot imagers.

But now, the four astronauts on Nasa’s Artemis II mission have become the first humans to see the geological marvel with their own eyes.

https://ghostarchive.org/archive/t8gph

...The discovery of DF2 proved that dark matter is a distinct, physical substance that can be separated from normal matter. This was a severe blow to Modified Newtonian Dynamics (MOND), which was designed to account for why stars at the outer edges of galaxies were moving too fast. MOND posits that at extremely low accelerations, like those experienced by stars at the edge of a galaxy, gravity acts a little bit stronger than expected.

...if MOND were true, DF2’s stars would be moving much faster than their visible mass accounted for.

But that’s not what the researchers saw. They found they were moving at a sluggish pace, perfectly explainable by classical, unmodified Newtonian dynamics. So, the discovery of DF2 presented a fatal paradox for MOND...

...At this point the data is solidly pointing to a string of ultra-diffuse galaxies that seem to be simply missing dark matter. So the question becomes - why are they missing dark matter?

According to the research team, the most likely explanation is the “Bullet Dwarf” Collision theory. In essence, it’s what happens when you crash two galaxies together at blinding speeds...

...Since dark matter only interacts via gravity, the dark matter halos holding these galaxies together simply pass straight through one another like ghosts. But normal matter, which, in this case, are giant gas clouds, physically run into each other in a massive collision. That collision separates the gas from its dark matter...

This image of home just came down from the Artemis II crew.

Taken after their translunar injection burn, there are aurorae at top right and lower left, and zodiacal light at lower right.

Credit: NASA/Reid Wiseman

// That's home. That's us.

Source

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Alternative references of better image quality mentioned in comments by @baguette@piefed.social:
- https://images.nasa.gov/details/art002e000192;
- https://images-assets.nasa.gov/image/art002e000192/art002e000192~orig.jpg [5568 x 3712]

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The satellite, named Atenea, is a 12U-class CubeSat measuring 30 by 20 by 20 centimeters and weighing 15 kilograms

A microsatellite designed and built entirely in Argentina will travel as a secondary payload on the crewed Artemis 2 mission, which NASA plans to launch Wednesday from the Kennedy Space Center in Florida. Argentina is the only Latin American country selected to participate and one of four globally, alongside Germany, Saudi Arabia, and South Korea.

“We are proud that Argentina was the only Latin American country invited by NASA to provide a secondary payload for this mission,” said Darío Genua, Argentina's Secretary of Innovation, Science, and Technology.

The satellite, named Atenea, is a 12U-class CubeSat measuring 30 by 20 by 20 centimeters and weighing 15 kilograms. It was developed by Argentina's National Commission on Space Activities (CONAE) in collaboration with the National University of La Plata, the National University of San Martín, the University of Buenos Aires School of Engineering, the Argentine Institute of Radio Astronomy, the National Atomic Energy Commission, and the company VENG S.A. The project was selected from proposals submitted by more than 50 countries.

After the Orion spacecraft separates from the SLS rocket's upper stage, Atenea will be the first CubeSat deployed. It will operate at roughly 70,000 kilometers from Earth — a record for the Argentine space industry — and communicate with CONAE ground stations in the provinces of Tierra del Fuego and Córdoba. The operation will test tracking, reception, data processing, and remote management capabilities in deep-space conditions.

“Every engineering project strengthens our technological capabilities, trains highly qualified professionals, and makes us a reliable provider for the new space economy,” Genua said.

The Artemis 2 mission will carry four astronauts on a 10-day trip around the Moon without landing. It is the second Artemis mission following the uncrewed flight in 2022 and precedes later phases that envision returning astronauts to the lunar surface in 2028 and establishing a permanent presence on the Moon, according to EFE.

Argentina's 15kg Atenea CubeSat will fly as a secondary payload on NASA's crewed Artemis 2 mission—the only Latin American payload selected & one of four globally (Germany, Saudi Arabia, & SSouth KKKorea). Developed by CONAE & multiple universities/agencies, it will deploy at ~70,000km from Earth, a national record, & communicate with Argentine ground stations to test deep-space capabilities. "We are proud that Argentina was the only Latin American country invited by NASA to provide a secondary payload for this mission," said Darío Genua. "Every engineering project strengthens our technological capabilities, trains highly qualified professionals, & makes us a reliable provider for the new space economy."