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New study: Transmission of epigenetic memory can be passed down through multiple generations

DNA strand,
Without altering the genetic code in the DNA, epigenetic modifications can change how genes are expressed, affecting an organism's health and development. The once radical idea that such changes in gene expression can be inherited now has a growing body of evidence behind it, but the mechanisms involved remain poorly understood.

A new study by researchers at UC Santa Cruz shows how a common type of epigenetic modification can be transmitted via sperm not only from parents to offspring, but to the next generation ("grandoffspring") as well. This is called "transgenerational epigenetic inheritance," and it may explain how a person's health and development could be influenced by the experiences of his or her parents and grandparents.

Comment: If applicable in humans, this study demonstrates the importance of maintaining a healthy lifestyle not only for oneself, but for also the health of one's children and grandchildren.

See also:


Comet 2

NASA's DART anti-asteroid satellite successfully smashes into space rock

Asteroid Didymos (top left) and its moonlet, Dimorphos
© Nasa
NASA has completed a key step of its "Double Asteroid Redirection Test" (DART), smashing a satellite roughly the size of a vending machine into a small moon that's about half-a-mile in diameter. The moon, Dimorphos, is orbiting an even larger asteroid, Didymos, and while neither is in any danger of colliding with Earth, they're good test cases to see whether us puny humans smashing them with technology can cause them to change course.

Comment:
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Seismograph

Mexico earthquake triggers 'desert tsunami' 1,500 miles away in Death Valley cave

Devil's Hole Death Valley
© Stan Shebs, via Wikimedia Commons
The Devil's Hole in Death Valley, California
About five minutes after the 7.6 magnitude earthquake hit near Mexico's southwest coast Monday, typically calm water deep in a Death Valley National Park cave started sloshing against the surrounding limestone rock.

The reverberations from the earthquake more than 1,500 miles away created what experts have called a "desert tsunami," which on Monday made waves erupt up to 4 feet high in the cave known as Devils Hole, a pool of water about 10 feet wide, 70 feet long and more than 500 feet deep, in Amargosa Valley, Nevada.

The water in the partially filled cave has become an "unusual indicator of seismic activity" across the world, with earthquakes across the globe — as far as Japan, Indonesia and Chile — causing the water to splash up Devils Hole, according to the National Park Service website.

Info

Planetary-scale 'heat wave' discovered in Jupiter's atmosphere

Jupiter Heat Wave
© Hubble / NASA / ESA / A. Simon (NASA GSFC) / J. Schmidt
An unexpected 'heat wave' of 700 degrees Celsius, extending 130,000 kilometres (10 Earth diameters) in Jupiter's atmosphere, has been discovered. James O'Donoghue, of the Japanese Aerospace Exploration Agency (JAXA), has presented the results this week at the Europlanet Science Congress (EPSC) 2022 in Granada.

Jupiter's atmosphere, famous for its characteristic multicoloured vortices, is also unexpectedly hot: in fact, it is hundreds of degrees hotter than models predict. Due to its orbital distance millions of kilometres from the Sun, the giant planet receives under 4% of the amount of sunlight compared to Earth, and its upper atmosphere should theoretically be a frigid -70 degrees Celsius. Instead, its cloud tops are measured everywhere at over 400 degrees Celsius.

"Last year we produced - and presented at EPSC2021 - the first maps of Jupiter's upper atmosphere capable of identifying the dominant heat sources," said Dr O'Donoghue. "Thanks to these maps, we demonstrated that Jupiter's auroras were a possible mechanism that could explain these temperatures."

Just like the Earth, Jupiter experiences auroras around its poles as an effect of the solar wind. However, while Earth's auroras are transient and only occur when solar activity is intense, auroras at Jupiter are permanent and have a variable intensity. The powerful auroras can heat the region around the poles to over 700 degrees Celsius, and global winds can redistribute the heat globally around Jupiter.

Comment: See also: Cosmic climate change: 'Space plasma hurricane' observed in ionosphere above North Pole!


Attention

NASA alarmed as astronauts' spacesuits keep filling up with water

spacesuit internation space station ISS
© NASA
German astronaut Matthias Maurer floats outside the International Space Station during a March 23 spacewalk. At the end of the outing, excess water made its way into his helmet, the first such intrusion since a similar but much more serious event in 2013. NASA has mounted an investigation to locate and correct the problem.
The spacesuits that allow astronauts to venture outside of the International Space Station have been declared "no-go" for upcoming spacewalks.

That's because the suits' helmets keep filling with excess water, a potentially life threatening scenario astronauts have been battling with on multiple occasions, CBS reports.

The massive and unwieldy suits, referred to as "extra-vehicular mobility units," (EMUs) aren't entirely off the table and could still be used in emergencies, according to NASA.

"Until we understand better what the causal factors might have been during the last EVA with our EMU, we are no-go for nominal [extra-vehicular activity]," Dana Weigel, deputy manager of the space station program at the Johnson Space Center, told reporters on Tuesday, as quoted by CBS. "So we won't do a planned EVA until we've had a chance to really address and rule out major system failure modes."

Comment: Is it that NASA isn't having the best of luck recently? Sabotage? Or is it yet another sign of how incompetence and corruption, that is destroying the US, has infiltrated even NASA?


Satellite

James Webb Space Telescope sends back stunning new images of Neptune

JWST neptune
© NASA, ESA, CSA, STScI
Webb’s Near-Infrared Camera (NIRCam) images objects in the near-infrared range from 0.6 to 5 microns, so Neptune does not appear blue to Webb. In fact, the methane gas so strongly absorbs red and infrared light that the planet is quite dark at these near-infrared wavelengths, except where high-altitude clouds are present. Such methane-ice clouds are prominent as bright streaks and spots, which reflect sunlight before it is absorbed by methane gas
NASA's James Webb Space Telescope shows off its capabilities closer to home with its first image of Neptune. Not only has Webb captured the clearest view of this distant planet's rings in more than 30 years, but its cameras reveal the ice giant in a whole new light.

Most striking in Webb's new image is the crisp view of the planet's rings - some of which have not been detected since NASA's Voyager 2 became the first spacecraft to observe Neptune during its flyby in 1989. In addition to several bright, narrow rings, the Webb image clearly shows Neptune's fainter dust bands.

"It has been three decades since we last saw these faint, dusty rings, and this is the first time we've seen them in the infrared," notes Heidi Hammel, a Neptune system expert and interdisciplinary scientist for Webb. Webb's extremely stable and precise image quality permits these very faint rings to be detected so close to Neptune.

Blue Planet

Indian subcontinent prone to regular, multi-year droughts, new study reveals

Mawmluh cave
© Ashish Sinha
Stalagmites in the Mawmluh cave, near the town of Cherrapunji in the state of Meghalaya — one of the wettest locations in the world.
A new study published in the Proceedings of the National Academy of Sciences reveals that catastrophic droughts — unlike anything observed in the last 150 years — have been a regular occurrence within the Indian subcontinent throughout the last 1,000 years. The troubling new data indicates that the region's current rainfall predictability could give way to decades-long drought, posing an enormous potential threat to human life if no mitigating measures are taken.

California State University, Dominguez Hills Professor of Earth Science Ashish Sinha was a lead author on the study, working alongside an international team of researchers to develop the new record. The team analyzed oxygen isotopes in stalagmites from the Mawmluh cave, near the town of Cherrapunji in the state of Meghalaya — one of the wettest locations in the world. The stalagmites work similarly to tree rings, recording the region's rainfall history within their geochemistry.

Comment: And it's not just India that has experienced repeated, seemingly cyclical, mega-droughts:


Info

Astronomers unveil new and puzzling features of mysterious Fast Radio Bursts

New study by international team of scientists reveals an evolving, magnetized environment and surprising source location for deep-space fast radio bursts - observations that defy current understanding.
Aperture Spherical radio Telescope (FAST) in China
© Jingchuan Yu
Artist's conception of Five-hundred-meter Aperture Spherical radio Telescope (FAST) in China.
Fast radio bursts (FRBs) are millisecond-long cosmic explosions that each produce the energy equivalent to the sun's annual output. More than 15 years after the deep-space pulses of electromagnetic radio waves were first discovered, their perplexing nature continues to surprise scientists - and newly published research only deepens the mystery surrounding them.

In the Sept. 21 issue of the journal Nature, unexpected new observations from a series of cosmic radio bursts by an international team of scientists - including UNLV astrophysicist Bing Zhang - challenge the prevailing understanding of the physical nature and central engine of FRBs.

The cosmic FRB observations were made in late spring 2021 using the massive Five-hundred-meter Aperture Spherical radio Telescope (FAST) in China. The team, led by Heng Xu, Kejia Lee, Subo Dong from Peking University, and Weiwei Zhu from the National Astronomical Observatories of China, along with Zhang, detected 1,863 bursts in 82 hours over 54 days from an active fast radio burst source called FRB 20201124A.

"This is the largest sample of FRB data with polarization information from one single source", said Lee.

Recent observations of a fast radio burst from our Milky Way galaxy suggest that it originated from a magnetar, which is a dense, city-sized neutron star with an incredibly powerful magnetic field. The origin of very distant cosmological fast radio bursts, on the other hand, remains unknown. And the latest observations leave scientists questioning what they thought they knew about them.

Microscope 1

Gene sharing is more widespread than thought, with implications for Darwinism

fern, plants
© Clyde Gravenberch via Unsplash
Evidence is growing that organisms share existing genetic information horizontally, not just vertically. This has immense implications for neo-Darwinian theory that are not yet fully recognized. If traits can be shared across species, genera and even phyla, they are not being inherited from common ancestors. The findings might also cast stories about convergence and co-evolution in a completely different light. Let's look at some of the news on this front.

Introgression

Last month, Current Biology posted a Primer on Introgression by four authors. Introgression refers to "lasting transfer of DNA from one of the species into the genome of the other" by means of hybridization and backcrossing. Basically, it describes "the incorporation of the DNA from one species into another."
Over the last few decades, advances in genomics have transformed our understanding of the frequency of gene flow between species and with it our ideas about reproductive isolation in nature. These advances have uncovered a rich and often complicated history of genetic exchange between species — demonstrating that such genetic introgression is an important evolutionary process widespread across the tree of life (Figure 1). [Emphasis added.]
Figure 1 in this open-access paper shows nine photos of creatures where "gene flow" has been inferred. They include vastly different organisms, from bacteria to birds, fish, and mammals — including humans. The authors strive to maintain Darwinism in their explanation, but this realization undermines what previously was explained by convergence or by independent origins of traits:
Instead of waiting for a beneficial mutation to arise, gene flow can instead introduce variation that has been 'pre-tested' by selection, allowing species to evolve rapidly. For instance, alleles causing brown winter coat color in snowshoe hares (Figure 1E), early flowering time in sunflowers or serpentine soil tolerance in Arabidopsis have introgressed from closely related species, which has facilitated adaptation to new environments.
The authors do not speculate at this time how common adaptive introgression might be.

Info

Mars might have been covered in lakes in the ancient past

Ancient MArs
© Ittiz/Wikipedia Commons
Artist's impression of Mars during the Noachian Era.
Ever since robotic explorers began visiting the Red Planet during the 1960s and 70s, scientists have puzzled over Mars' surface features. These included flow channels, valleys, lakebeds, and deltas that appear to have formed in the presence of water. Since then, dozens of missions have been sent to Mars to explore its atmosphere, surface, and climate to learn more about its warmer, wetter past. In particular, scientists want to know how long water flowed on the surface of Mars and whether it was persistent or periodic in nature.

The ultimate purpose here is to determine whether rivers, streams, and standing bodies of water existed long enough for life to emerge. So far, missions like Curiosity and Perseverance have gathered volumes of evidence that show how hundreds of large lakebeds once dotted the Martian landscape. But according to a new study by an international team of researchers, our current estimates of Mars' surface water may be a dramatic understatement. Based on a meta-analysis of years' worth of satellite data, the team argues that ancient lakes may have once been a very common feature on Mars.

The research was led by Dr. Joseph Michalksi, an associate professor with the Department of Earth Sciences and the Deputy Director of the Laboratory for Space Research (LSR) at the University of Hong Kong (HKU). He was joined by researchers from the Canadian Institute for Advanced Research (CIFAR), the Center for Planetary Systems Habitability at UT Austin, the University of British Columbia (UBC), the Natural History Museum, and Brown and Georgetown University. The paper that describes their findings, titled "Geological diversity and microbiological potential of lakes on Mars," recently appeared in the journal Nature.