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It has become trivially easy to use artificial intelligence to edit images or generate video to remove unwanted objects or beautify scenes, but doing so leads to people misremembering what they have seen

It has become trivially easy to use artificial intelligence to edit images or generate video to remove unwanted objects or beautify scenes, but doing so leads to people misremembering what they have seen

A puzzling discrepancy in measurements of the mass of the W+ and W– bosons, which are fundamental particles that carry the weak force, has been resolved by the Large Hadron Collider.

Flawed implementation of a global eradication strategy brought poliovirus to Gaza, and wartime conditions let the infection spread

A SpaceX Falcon 9 rocket carrying the company’s Dragon spacecraft is launched on NASA’s SpaceX Crew-8 mission to the International Space Station with NASA astronauts Matthew Dominick, Michael Barratt, and Jeanette Epps, and Roscosmos cosmonaut Alexander Grebenkin onboard, Sunday, March 3, 2024, at NASA’s Kennedy Space Center in Florida.NASA/Aubrey Gemignani

NASA invites the public to participate as virtual guests in the launch of the agency’s SpaceX Crew-9 mission. NASA astronaut Nick Hague, commander, and Roscosmos cosmonaut Aleksandr Gorbunov, mission specialist, will embark on a flight aboard a SpaceX Dragon spacecraft, launching no earlier than 1:17 p.m. EDT on Saturday, Sept. 28, from Space Launch Complex-40 at Cape Canaveral Space Force Station in Florida.

Members of the public can register to attend the launch virtually. Virtual guests for this mission will receive curated resources, interactive opportunities, updates with the latest news, and a mission-specific collectible stamp for their virtual guest passport after liftoff. Don’t have a passport yet? Print yours here and get ready to add a stamp!

Live coverage and countdown commentary will begin at 9:10 a.m. EDT Saturday, Sept. 28, streaming on NASA+  agency’s website. Learn how to stream NASA content on a variety of platforms, including social media.

Want to learn more about the mission and NASA’s Commercial Crew Program? Follow along on the mission blog, Commercial Crew blog, @commercial_crew on X, or check out Commercial Crew on Facebook.

The reason we call dark matter dark isn’t because it’s some shadowy material. It’s because dark matter doesn’t interact with light. The difference is subtle, but important. Regular matter can be dark because it absorbs light. It’s why, for example, we can see the shadow of molecular clouds against the scattered stars of the Milky Way. This is possible because light and matter have a way to connect. Light is an electromagnetic wave, and atoms contain electrically charged electrons and protons, so matter can emit, absorb and scatter light. Dark matter isn’t electrically charged. It has no way to connect with light, and so when light and dark matter meet up they simply pass through each other.

All of our observations suggest that dark matter and light only have gravity in common. When dark matter is clustered around a galaxy, for example, its gravitational tug can deflect light. Because of this we can map the distribution of dark matter in the Universe by observing how light is gravitationally lensed around it. We also know that dark and regular matter interact gravitationally. The tug of dark matter causes galaxies to gather together into superclusters. But an unanswered question is whether dark and regular matter only interact gravitationally. If an atom and dark matter particle intersected, would they really just pass through each other?

Since we haven’t directly observed dark matter particles we can only speculate, but most dark matter models argue that gravity is the only common link with light and regular matter. Dark and regular matter clump around each other, but they don’t collide and merge like interstellar clouds. But a new study suggests the two do interact, which could reveal subtle aspects of the mysterious stuff.

The study looks at six ultrafaint dwarf galaxies, or UFDs. They are satellite galaxies near the Milky Way that seem to have far fewer stars than their mass would suggest. This is because they are mostly made of dark matter. If regular and dark matter only interact gravitationally, then the distribution of stars in these small galaxies should follow a certain pattern. If dark and regular matter interact directly, then this distribution will be skewed.

To test this the team ran computer simulations of both scenarios. They found that in the non-interacting model the distribution of stars should become more dense in the center of the UFDs and more diffuse at the edges. In the interacting model the stellar distribution should be more uniform. When they compared these models with observations of the six galaxies, they found the interacting model was a slightly better fit.

So it seems dark and regular matter interact in ways beyond their gravitational tugs. There isn’t enough data to pin down the exact nature of the interaction, but the fact there is any interaction at all is a surprise. It means that our traditional models of dark matter are at least partly wrong. It may also point the way toward new methods of detecting dark matter directly. In time we may finally solve the mystery of this dark, but not entirely invisible, material.

Reference: Almeida, Jorge Sánchez, Ignacio Trujillo, and Angel R. Plastino. “The Stellar Distribution in Ultrafaint Dwarf Galaxies Suggests Deviations from the Collisionless Cold Dark Matter Paradigm.” The Astrophysical Journal Letters 973.1 (2024): L15.

The post Dark Matter Could a Have Slight Interaction With Regular Matter appeared first on Universe Today.

Replacing some existing vegetable oil crops with camellia oil could boost production while reducing environmental impacts such as greenhouse gas emissions

Replacing some existing vegetable oil crops with camellia oil could boost production while reducing environmental impacts such as greenhouse gas emissions

The world's most remote island, where moai stand and stare at the stars, will experience an annular solar eclipse on Oct. 2, 2024. For one eclipse-chaser, it's unmissable.

Why ordinary people will follow orders to the point of hurting others remains a critical question for scientists—though some answers have emerged

We have known that water ice exists on the Moon since 1998. These large deposits are found in the permanently shadowed craters around the polar region. The challenge is how to get it since shadowed craters are not the best place for solar powered vehicles to operate. A team of engineers have identified a design for an ice-mining vehicle powered by americium-241. With a half-life of 432 years, this element is an ideal power source for a vehicle to operate in the dark for several decades. 

Ice in the polar regions of the Moon is of vital importance for our future space explorations, not just lunar visits but as we stretch our legs in the Solar System. Its thought to be ancient material deposited by comets or formed by interactions with solar wind. It is expensive to take materials to the Moon so harvesting on site is far more efficient. Ice on the Moon can provide drinking water, oxygen for breaking and even hydrogen for rocket fuel. Surveys suggest something in the region of 600 billion kilograms of ice deposited at the lunar poles. 

Exposed water ice (green or blue dots) in lunar polar regions and temperature. Credit: Shuai Li

The challenge facing future lunar harvesting missions is that operations in the permanently  shadowed regions (or PSRs as they have been called) cannot be powered by solar panels as is often the case. The environment is cold too, in the region of 40K, that’s -233?C and at those temperatures special power considerations are required. 

A team of researchers have been exploring the use of Radioisotope Power Systems (RPS) to provide thermal and electrical power systems. These power systems have been used before during deep space missions for example Voyager and New Horizons. They work by generating electricity using the heat that is released from the natural decay of a radioactive isotope usually plutonium-238.

Artist rendition of Voyager 1 entering interstellar space. (Credit: NASA/JPL-Caltech)

The team led by Marzio Mazzotti from the University of Leicester have explored an ice-mining rover using power generated by the radio activate decay fo Americium-241. It has a half-life of 432 years which means it takes 432 years for half of a sample of Americium to decay. During this time, half of the atoms in the substance will transform into a different element. Using this power source will provide a stable power supply for an ice-mining rover in the darkness of the lunar polar craters for decades.

Apollo 17 commander Eugene Cernan with the lunar rover in December 1972, in the moon’s Taurus-Littrow valley. Credit: NASA

Using a radioisotope power system is not new however the team came upon the idea that the excess heat that is not used can be used to thermally mine ice from samples of lunar material. The rover would be fitted with a sublimation plate that would turn any ice deposits into a gas which would be collected in a cold trap.

The team developed a model of its Thermal Management System and tested it for icy regolith (the fine dusty lunar surface) material with a water ice content of 0-10 vol %. Their simulations showed that it is possible to mine ice using thermal techniques in the PSR of the Moon using an RPS (I had to really concentrate writing that sentence!) powered lunar rover. 

Source : Ice-Mining Lunar Rover using Americium-241 Radioisotope Power Systems

The post A New Rover Design Could Crawl Across the Moon for Decades Harvesting Water appeared first on Universe Today.

An office in the Pentagon investigated UFOs—and the paranormal—over a decade ago, segueing into a long saga leading to Congressional hearings and breathless news stories today. But the real story looks more like former defense officials pushing their personal mythology, rather than any cover-up of aliens

A distant planet should have been consumed when its star expanded to become a red giant, perhaps offering insights into planetary migration

A distant planet should have been consumed when its star expanded to become a red giant, perhaps offering insights into planetary migration

Only 2 astronauts will launch to the ISS Sept. 26 with SpaceX instead of the planned 4. We spoke with the crew before the big change was made.

Earth will get a "new moon" this weekend when, on Sunday (Sept. 29), it captures the asteroid 2024 PT5, claiming it as a very temporary "mini-moon."

For northern hemisphere dwellers, September's Full Moon was

Spanning light-years, this

Radar images have captured snowman-shaped 2024 ON asteroid tumbling through space.

A flurry of studies has found microplastics in nearly every organ in the human body, from the brain to the testicles. But very few have revealed whether these tiny bits of plastic impact our health