Solar eclipse tomorrow, other astronomical news


This video says about itself:

United States Total Solar Eclipse 21 Aug 2017

19 August 2017

On August 21, 2017 a total solar eclipse occurs from the Northwest to the Southeast. This video explains what happens and why and the possible influence coming from an eclipse.

Eclipse watchers will go after the biggest solar mystery: Why is the corona so hot? Usually when you move away from a heat source, it gets cooler. Not so in the sun’s atmosphere. By Lisa Grossman, 6:00am, August 20, 2017.

Does the corona look different when solar activity is high versus when it’s low? One U.S. town will get two eclipses in seven years, making it the best place to watch the sun’s cycle in action. By Lisa Grossman, 7:00am, August 19, 2017.

Where does the solar wind come from? The eclipse may offer answers. A look at where the sun’s surface meets its atmosphere could reveal the wind’s origins. By Lisa Grossman, 7:00am, August 18, 2017.

Here are the paths of the next 15 total solar eclipses. From 2017 to 2040, there will be 15 total solar eclipses. Here‘s a map of where to see them. By Emily DeMarco, 2:30pm, August 18, 2017.

Cosmic lens lets astronomers zoom in on a black hole’s burps. Seeing into the heart of a faraway galaxy could explain how jets of hot material get their start. By Lisa Grossman, 5:01pm, August 18, 2017.

We share the Milky Way with 100 million black holes. New census estimates the number of cosmic chasms based on galaxy size and makeup. By Emily Conover, 9:00am, August 18, 2017.

Solar eclipse in the USA 21 August update


This video from the USA says about itself:

August 21st Solar Eclipse Will Be Extraordinary And Rare Celestial Event! Watch To Know Why

16 August 2017

2017 Solar Eclipse Will Be Extraordinary.

Historic Solar Eclipse Just One Week Away.

What can the eclipse tell us about the corona’s magnetic field? Scientists want to directly measure the forces behind the wispy dancing plasma in the sun’s atmosphere. By Lisa Grossman, 7:00am, August 16, 2017.

Protect little ones’ eyes from the sun during the eclipse. By Laura Sanders, 5:20pm, August 15, 2017.

Eclipses show wrong physics can give right results. Success of astronomical predictions reveals power of science, by Tom Siegfried. 3:30pm, August 17, 2017.

Solar eclipse, 21 August 2017


This video from the USA says about itself:

Eclipses Throughout our Universe | Out There | Solar Eclipse 2017

14 aug. 2017

On the 21st day of August, 2017, the moon will slide between the Earth and the sun, painting a swath of darkness across North America. The Great American Solar Eclipse.

An exercise in cosmic geometry. A reminder that we live on one sphere among many, all moving to the laws of Kepler, Newton and Einstein. The moon’s orbit around the Earth is slightly tilted, so the shadow of the new moon usually passes above or below us. About twice a year, the three bodies briefly align, and the moon’s long shadow cuts across our planet. The day dies and is reborn. The sun is replaced by an inky hole, feathered with the pale corona, a million degrees hotter than the sun itself. Staring up into the cone of blackness you can feel the cosmic gears grinding. Two minutes of beauty and terror.

What happens in Earth’s atmosphere during an eclipse? Using smartphones and radio kits, researchers will track changes in how radio waves travel through the ionosphere. By Lisa Grossman, 7:00am, August 13, 2017.

Can the eclipse tell us if Einstein was right about general relativity? He probably was, but astronomers will put his 1915 theory to the test with DIY experiments. By Lisa Grossman, 7:00am, August 15, 2017.

What can we learn about Mercury’s surface during the eclipse? A telescope aboard a pair of research jets will make a thermal map of the planet during the eclipse. By Lisa Grossman, 7:00am, August 14, 2017.

Solar eclipse in the USA, August 21


This video from the USA says about itself:

Get ready for the total solar eclipse: Here’s what to expect | CNBC

11 August 2017

Jeffrey Kluger, Time Magazine editor-at-large and author of “Apollo 8,” discusses the cross-country total solar eclipse on August 21st.

As the moon passes in front of the sun during the Aug. 21 Great American Eclipse, scientists will be doing some serious work: here.

The Great American Eclipse on August 21 will be much more than a spectacle. As the moon passes in front of the sun, scientists will be doing some serious work. A fleet of telescopes, spectrometers and polarizers will turn skyward to look directly at the parts of our nearest star that are usually invisible: here.

What do plants and animals do during an eclipse? A citizen science project aims to gather data to put science behind anecdotal evidence. By Lisa Grossman, 7:00am, August 12, 2017.

Moon had a magnetic field for at least a billion years longer than thought: here.

August solar eclipse, more astronomy


This video from the USA says about itself:

August solar eclipse may be most viewed ever

21 June 2017

On Aug. 21, the moon will pass between the Earth and the sun, casting a shadow that will race across the heartland of America at some 1,500 mph, moving over 14 states from Oregon to South Carolina as the United States experiences its first total eclipse of the sun since 1979 and the first coast-to-coast eclipse in 99 years.

More than 200 million people live within a one-day drive of the 70-mile-wide path of totality, officials said Wednesday, which will carry the moon’s shadow across hundreds of towns and cities and 20 national parks where record crowds are expected. Researchers said it may be the most watched, best observed solar eclipse in history.

Passing over Salem, Oregon, around 1:15 p.m. EDT, the moon’s shadow will race across Idaho Falls, Casper, Wyoming, most of Kansas City and parts of St. Louis before passing over Nashville — the largest city directly in the path of totality — and then darkening the sky over Greenville, Columbia and Charleston, South Carolina. The central shadow will move out over the Atlantic Ocean around 2:48 p.m. NASA has posted a variety of maps, animations and videos showing the path of the eclipse, including a zoomable pdf and an interactive map showing when the eclipse begins, reaches maximum and ends for any point in the nation. It also shows the duration of the eclipse for each location in the path of totality.

“This is a really amazing chance to just open the public’s eyes to wonder, and to get people thinking about the most amazing natural phenomenon that happens on the surface of the Earth, a total solar eclipse, and to incorporate that into thinking about what’s going on in our cosmos,” said Angela Des Jardins, a researcher at Montana State University.

Balloons will broadcast the 2017 solar eclipse live from on high. Astrophysicist Angela Des Jardins wants to show the world in first-of-its-kind livestream. By Lisa Grossman, 1:30pm, July 26, 2017.

Half of the Milky Way comes from other galaxies. Simulations suggest that galactic winds blew the material in from elsewhere. By Ashley Yeager, 9:00pm, July 26, 2017.

Astronomical update


This video says about itself:

Jill Tarter: Why the search for alien intelligence matters

20 February 2009

The SETI Institute‘s Jill Tarter makes her TED Prize wish: to accelerate our search for cosmic company. Using a growing array of radio telescopes, she and her team listen for patterns that may be a sign of intelligence elsewhere in the universe.

‘Making Contact’ chronicles an astronomer’s struggle to find E.T. For decades, Jill Tarter led the hunt for extraterrestrial intelligence. By Emily Conover, 4:33pm, July 24, 2017.

Fewer big rogue planets roam the galaxy, recount shows. New estimate of wandering Jupiter-mass worlds better matches ideas of how planets become orphans. By Ashley Yeager, 11:00am, July 24, 2017.

Origin of life on land, not in the sea?


This video says about itself:

2 May 2017

3.5 billion year old fossils hint life evolved in pond, not sea

It’s the age-old question: where do we come from? New fossil evidence suggests the first spark of life may have occurred in a hot spring on land rather than a hydrothermal vent in the deep sea.

Charles Darwin proposed in 1871 that life originated in a “warm little pond”. But the dominant theory nowadays is that primitive microorganisms first assembled in hot, chemical-rich water at hydrothermal vents at the bottom of the ocean.

One reason for favouring this marine model is that fossil evidence of early land-based microbial life has been lacking. Until recently, the oldest evidence of life on land was only 2.8 billion years old, whereas the oldest evidence from the sea was 3.7 billion years old.

Now, a team led by Tara Djokic at the University of New South Wales in Australia has discovered fossils of land-based microorganisms. They were found in 3.5-billion-year-old rocks in an extinct volcano in the Dresser Formation in the hot, dry, remote Pilbara region of Western Australia.

The fossils include stromatolites – layered rock structures created by microorganisms – and circular holes left in the rock by gas bubbles that look like they were once trapped by sticky microbial substances. Both types of structures are preserved in geyserite, a type of rock that is only found in and around freshwater hot springs in volcanic areas on land.

Land-based launch pad?

The findings suggest that microbes were present on land and in the ocean around the same time, says Djokic. The question is – which came first?

“There are now a number of converging lines of evidence that point to terrestrial hot springs over hydrothermal vents for the origin of life,” says Djokic.

Small bodies of water like hot springs may have been more conducive to the formation of life because they can evaporate and concentrate the building blocks of life, says Djokic. “In hot springs, you’ve also got a nutritious concoction of elements because hot fluids circulate through the underlying rocks and bring up different minerals,” she says.

Recent research suggests that the element mix in ancient hot springs would have been more likely to give rise to life than that of deep sea vents.

Primitive microorganisms formed in the springs could have then spread to the sea, where they could have adapted and continued to evolve, Djokic says.

The findings are compelling, says Gregory Webb at the University of Queensland in Australia. “There are lots of microbes that live in terrestrial hot springs today, so it’s not a stretch to believe that an ancient hot spring could have accommodated life,” he says.

Then again, making assertions about life on early Earth is tricky, says Webb. “Microbial life isn’t easy to see, even today, so rocks that preserve evidence of ancient bacteria are hard to find and hard to study.” He is not ruling out the deep sea model of the origin of life.

Ancient life on Mars

Djokic and her colleagues believe the research could have implications for the search for ancient life on Mars. Earth and Mars both formed around 4.5 billion years ago and had volcanoes and hot springs dotted across their surfaces.

“If life can be preserved in hot springs so far back in Earth’s history, then there is a good chance it could be preserved in Martian hot springs too,” says Djokic.

One of the three potential landing sites for NASA’s Mars 2020 rover mission is Columbia Hills, a rocky formation that is thought to have once been a hot spring environment.

From the University of California – Santa Cruz in the USA:

Did life begin on land rather than in the sea?

A paradigm-shifting hypothesis could reshape our idea about the origin of life

July 18, 2017

Summary: A new discovery pushes back the time for the emergence of microbial life on land by 580 million years and also bolsters a paradigm-shifting hypothesis that life began, not in the sea, but on land.

For three years, Tara Djokic, a Ph.D. student at the University of New South Wales Sydney, scoured the forbidding landscape of the Pilbara region of Western Australia looking for clues to how ancient microbes could have produced the abundant stromatolites that were discovered there in the 1970s.

Stromatolites are round, multilayered mineral structures that range from the size of golf balls to weather balloons and represent the oldest evidence that there were living organisms on Earth 3.5 billion years ago.

Scientists who believed life began in the ocean thought these mineral formations had formed in shallow, salty seawater, just like living stromatolites in the World Heritage-listed area of Shark Bay, which is a two-day drive from the Pilbara.

But what Djokic discovered amid the strangling heat and blood-red rocks of the region was evidence that the stromatolites had not formed in salt water but instead in conditions more like the hot springs of Yellowstone.

The discovery pushed back the time for the emergence of microbial life on land by 580 million years and also bolstered a paradigm-shifting hypothesis laid out by UC Santa Cruz astrobiologists David Deamer and Bruce Damer: that life began, not in the sea, but on land.

Djokic’s discovery — together with research carried out by the UC Santa Cruz team, Djokic, and Martin Van Kranendonk, director of the Australian Centre for Astrobiology — is described in an eight-page cover story in the August issue of Scientific American.

“What she (Djokic) showed was that the oldest fossil evidence for life was in fresh water,” said Deamer, a lanky 78-year-old who explored the region with Djokic, Damer, and Van Kranendonk in 2015. “It’s a logical continuation to life beginning in a freshwater environment.”

The model for life beginning on land rather than in the sea could not only reshape our idea about the origin of life and where else it might be, but even change the way we view ourselves.

The right conditions for life

For four decades, ever since the research vessel Alvin discovered deep-sea hydrothermal vents that were habitats for specialized bacteria and worms that looked like something out of a science-fiction novel, scientists have theorized that these mineral- and gas-pumping vents were just what was needed for life to begin.

But Deamer, who describes himself as a scientist who loves playing with new ideas, thought the theory had flaws. For instance, molecules essential for the origin of life would be dispersed too quickly into a vast ocean, he thought, and salty seawater would inhibit some of the processes he knew are necessary for life to begin.

Deamer had spent the early part of his career studying the biophysics of membranes composed of soap-like molecules that form the microscopic boundaries of all living cells. Later, given a piece of the Murchison meteorite that had landed in Australia in 1969, Deamer found that the space rock also contained soap-like molecules nearly 5 billion years old that could form stable membranes. Still later, he demonstrated that membranes helped small molecules join together to form longer information-carrying molecules called polymers.

Trekking to volcanoes from Russia to Iceland and hiking through the Pilbara desert, Deamer and his colleagues observed volcanic activity that suggested the idea that hot springs provided the right environment for the beginning of life. Deamer even built a machine that simulated the heat, acidity, and wet-and-dry cycles of hot springs and installed it in his lab on the UC Santa Cruz campus.

“I think, every once in awhile, you have to be brave enough and bold enough to try new ideas,” Deamer said. “Of course, some of my colleagues think even ‘foolish enough.’ But that’s the chance you take.”

Rethinking the timeline

In Deamer’s vision, ancient Earth consisted of a huge ocean spotted with volcanic land masses. Rain would fall on the land, creating pools of fresh water that would be heated by geothermal energy and then cooled by runoff. Some of the key building blocks of life, created during the formation of our solar system, would have fallen to Earth and gathered in these pools, becoming concentrated enough to form more complex organic compounds.

The edges of the pools would go through periods of wetting and drying as water levels rose and fell. During these periods of wet and dry, lipid membranes would first help stitch together the organic compounds called polymers and then form compartments that encapsulated different sets of these polymers. The membranes would act like incubators for the functions of life.

Deamer and his team believe the first life emerged from the natural production of vast numbers of such membrane-encased “protocells.”

While there is still debate about whether life began on land or in the sea, the discovery of ancient microbial fossils in a place like the Pilbara shows that these geothermal areas — full of energy and rich in the minerals necessary for life — harbored living microorganisms far earlier than believed.

The search for life on other planets

According to Deamer and his colleagues, this discovery and their hot-springs-origins model also have implications for the search for life on other planets. If life began on land, then Mars, which was found to have a 3.65-billion-year-old hot spring deposits similar to those found in the Pilbara region of Australia, might be a good place to look.

For Damer, the new “end-to-end hypothesis” of how life began on land offers something else: that the origin of life was not just a simple story of individual, competing cells. Rather that a plausible new vision of life’s start could be a communal unit of protocells that survived and evolved through collaboration and sharing of innovation rather than strict competition.

“That,” he said, “is a fundamental shift that might impact how we think of our world, ourselves, and our future: as dependent on collaboration as much as being driven by competition.”

Sitting in his fourth-floor office on campus, Deamer smiled as he recounted the letter Charles Darwin wrote to a friend in 1871, which speculated that life might have begun in “some warm little pond.”

That’s not far off the mark, Deamer said, “except we call ours ‘hot little puddles.'”

Conventional scientific wisdom has it that plants and other creatures have only lived on land for about 500 million years, but a new study is pointing to evidence for life on land that is four times as old — at 2.2 billion years ago and almost half way back to the inception of the planet: here.

The earliest example of an organism living on land — an early type of fungus — has been identified. The organism, from 440 million years ago, likely kick-started the process of rot and soil formation, which encouraged the later growth and diversification of life on land: here.