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Member since: Wed Oct 13, 2004, 05:42 PM
Number of posts: 6,897

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The Magic of the Summer Solstice

From Huffington Post: Stunning Photos From Around the World Show the Power of the Summer Solstice:

If you peered up into the sky at any point on Monday, you likely would have seen a big, beautiful full moon shining down at you. The June full moon, nicknamed the “Strawberry Moon” by indigenous American tribes, fell on the summer solstice this year — the first time the two coincided since the 1967 Summer of Love.

Summer solstice is the longest day of the year, and it’s one of celebration and reverence for many around the world, including some Pagans, Druids, Incans, and spiritual seekers. Celebrations typically honor the power of the sun, but this year, the full moon also showed off its glory by lighting the sky long into the night.

A full moon behind Glastonbury Tor near Somerset, UK

The full moon rises behind above the ancient marble Temple of Poseidon at Cape Sounion, southeast of Athens.

Aymara indigenous hold up their hands to receive the first rays of sunlight in a New Year’s ritual in the ruins of the ancient city Tiwanaku, Bolivia, early Tuesday, June 21, 2016.

Photos of revelers at Stonehenge, on Salisbury Plain in southern England, Britain June 21, 2016.

Israelis gather to watch the sunrise on the summer solstice, the longest day of the year, at Rujum el-Hiri located in the central part of the Golan Heights on June 21, 2016.

Cpl. Kareem Rashad Sultan Khan Was An American Soldier

...and a Muslim, who died for this country!

This picture of Elsheba Khan mourning at her son's grave has, deservedly, gone viral:

Crazy Bernie -AD | Bernie Sanders vs Trump

New Paradigms for SETI: Cosmic Archeology

The Centauri Dreams website has run several recent posts on the Search for Extra-Terrestrial Intelligence that suggest new directions for the search. The most recent: Perspectives on Cosmic Archeology discusses the implications of the final factor in the Drake Equation: The lifetime of a technological civilization.

By ‘technological,’ Drake was referring to those civilizations that were capable of producing detectable signals; i.e., releasing electromagnetic radiation into space. And when we have but one civilization to work with as example, we’re hard pressed to know what this factor is. This is where Adam Frank (University of Rochester) and Woodruff Sullivan (University of Washington, Seattle) come into the picture. In a new paper in Astrobiology, the researchers argue that there are other ways of addressing the ‘lifetime’ question.

What Came Before Us

The idea is to calculate how unlikely our advanced civilization would be if none has ever arisen before us. In other words, Frank and Sullivan want to put a lower limit on the probability that technological species have, at any time in the past, evolved elsewhere than on Earth. Here’s how their paper describes this quest:

Standard astrobiological discussions of intelligent life focus on how many technological species currently exist with which we might communicate (Vakoch and Dowd, 2015). But rather than asking whether we are now alone, we ask whether we are the only technological species that has ever arisen. Such an approach allows us to set limits on what might be called the ‘‘cosmic archaeological question’’: How often in the history of the Universe has evolution ever led to a technological species, whether short- or long-lived? As we shall show, providing constraints on an answer to this question has profound philosophical and practical implications.


The paper is short and interesting; I commend it to you. The result it produces is that human civilization can be considered unique in the cosmos only if the odds of a civilization developing are less than one part in 10 to the 22nd power. Frank and Sullivan call this the ‘pessimism’ line. If the probability of a technological civilization developing is greater than this standard, then we can assume civilizations have formed before us at some time in the universe’s history.

And yes, this is a tiny number — one in ten billion trillion. Frank says in this University of Rochester news release that he believes it implies technology-producing species have evolved before us. Even if the chances of civilization arising were one in a trillion, there would be about ten billion civilizations in the observable universe since the first one arose. As for our own galaxy, another civilization is likely to have appeared at some point in its history if the odds against it evolving on any one habitable planet are better than one in 60 billion.


I always appreciate work that frames an issue in a new perspective, which is what Frank and Sullivan’s paper does. We can’t know whether there are other civilizations currently active in our galaxy, but it appears that the odds favor their having arisen at some time in the past. In fact, these numbers show us that we are almost certainly not the first technological civilization to have emerged. Is the galaxy filled with the ruins of civilizations that were unable to survive, or is it a place where some cultures have mastered the art of keeping themselves alive?

As a commentary on that last paragraph, I'd like to offer Randall Munroe's famed statement:

That sentiment has been shared by Prof. Steven Hawking, as well as the late Dr. Carl Sagan and Arthur C. Clarke.

NASA Marks Earth Day With #24/7 Celebration

Join NASA for a #24Seven Celebration of Earth Day:

On April 22, NASA will post about 200 images across nearly 100 different social media channels that capture the breadth of the agency’s 24-hour-a-day work to study Earth. The images were captured during the week of March 27, but have been assembled chronologically to tell a story of a “day in the life” of NASA’s Earth science work. The time-stamped posts -- hashtagged #24Seven -- will begin publishing at 12:01 a.m. EDT and will continue throughout the day.

Share your posts on Twitter or Instagram with the hashtag #24Seven, or on our Facebook Event page.We know we aren’t the only people working to safeguard and understand our home planet. As you celebrate Earth Day, we’re asking you to share on social media what you’re doing to mark the day and celebrate our fragile home in space.

Share your posts on Twitter or Instagram with the hashtag #24Seven, or on our Facebook Event page.


How can I take part?

Millions of people will take time out of their day this April 22 to do their part to make Earth a better place. Others will mark the day by spending it outside, celebrating the beauty, ruggedness and life-giving elements that make Earth our home in the solar system.

Take a picture or a short video of whatever Earth-focused activity you are doing on Earth Day and post it on social media with the hashtag #24Seven. Pictures and videos can be posted to Twitter, Instagram and to the official NASA Facebook Event page.

Begin posting at 6 a.m. EDT on April 21 – which marks the beginning of Earth Day on the international date line at Samoa and Christmas Island, Kiribati – and continue posting until 8 a.m. EDT on April 23, which marks the end of Earth Day on the other side of the international date line at Baker Island.

Some of the first images from NASA's 24/Seven Earth Day Celebration:

Gallery of Pics from the Marches for Low-Wage Workers in Kansas City

There was a day of strikes, protests and marches in Kansas City Thursday. The movement was originally started for fast-food workers in 2013; since then, janitors, child-care workers, hospital workers and even adjunct professors have joined the movement.

There are protests going on in 300 US cities and 40 countries. The demands are the same:
  • A decent, living wage - $15 in the US,
  • The right to unionize,
  • Affordable child care.

Voyage to Planet Nine

The Centauri Dreams blog can be a fun place to visit; subject range from planetary science to Search for Extra-Terrestrial Intelligence to interstellar travel. Their most recent post is speculation on missions to the hypothetical 'Planet Nine' way out in the 'burbs of the solar system. The author, Adam Crowl is a member of the Icarus Interstellar project to redesign the Daedalus interstellar probe, proposed by the British Interplanetary Society in the late '70s.

In The Snowbank Orbit, Redux, Adam speculates about the hypothetical planet and how a future mission might not only reach the planet, but go into orbit around it:

Fritz Leiber is better known for his fantasy and SF-fantasy, but he could write hard-SF too. A fine example is his 1962 story, “The Snowbank Orbit”, the title of which alludes to World War II tales of pilots surviving bailouts without parachutes by plunging into snow-drifts. Five spacecraft, racing towards Uranus at 100 miles per second with empty tanks, intend a fiery plunge through the planet’s atmosphere to brake into orbit. The rest of that story I will leave to the interested reader (available here) but the idea of aerobraking into orbit around a distant Planet Nine is worth discussing.

Presently we know very little about Telisto – the mellifluous name suggested for Planet Nine by physicist Lorenzo Iorio which I’ll use for convenience. Brown & Batygin suggest an orbit averaging about 700 AU and a mass of at least 10 Earth masses. The mass could be somewhat higher, though certainly not of the order of a Saturn-mass as its infra-red glow would’ve been seen by earlier surveys. Modelling suggests a 10 Earth-mass planet, with a substantial hydrogen-helium envelope, could be as ‘warm’ as 50 K – about 40 degrees warmer than the ~10 K from sunlight alone. A range of compositions were modelled. A Super-Earth, an Ice-Giant (like Uranus/Neptune) and a miniature version of Jupiter/Saturn are all possible. Some cosmogonic simulations suggest a Neptune like object is likely to have been flung from amongst the other giant planets during their formation, so it seems the most likely option.

A Neptune-like Telisto would then be an ice-wrapped rocky core wrapped in a layer of captured hydrogen/helium mixture. It’s likely that hydrogen will be depleted from its atmosphere by some fraction being chemically bound and mixed with its core, so helium will be a higher fraction of the atmosphere, as appears to be the case for Neptune. If the atmosphere is a small fraction of Telisto’s mass, then it’s possible it will have an icy surface or even a liquid water ocean under a hydrogen atmosphere via its greenhouse effect trapping the planet’s internal heat. In that case Telisto will be very interesting from an astrobiological perspective, though the energy sources available to sustain life are impossible to quantify at present.

Adam, and others, are already thinking about how a future probe might reach Tellisto and set up orbit around it.

Deep Space Propulsion

Given sufficient motivation we’ll send a probe and eventually follow in person. Getting there will be a challenge. At the present 3.5 AU/year of “Voyager 1” the journey would take 200 years. Leiber’s 100 miles per second would get a probe there in 20 years, which might be acceptable if the probe has a compelling secondary mission it can pursue during the long cruise phase. Long baseline telescopic observations might be sufficiently attractive to combine the two. A flyby at 100 miles per second is probably too quick to provide sufficient science return for the investment, so stopping will be required.

The article discusses various means of propulsion, including ion engines powered by advanced forms of nuclear reactors and various sails: lightsails, 'e-sails' and magsails. I'm disappointed that Adam didn't include the VASIMR (Variable Specific Impulse Magnetoplasma Rocket engine), which might have advantages over ion engines.

Adam suggests the proposed Telisto probe use a aerobraking to slow enough to enter orbit around the planet.

Let's start a Bernie Playlist in celebration of Victory!!!!!

I've been hearing these tunes at Bernie Rallies ever since Iowa:

Muse: Uprising

Neil Young: Rockin' in the Free World:

Power to the People

Please add your your choices.......

President Cthulhu?????

Could Cthulhu trump the other Super Tuesday contenders?:

A mighty bruiser is rising in the US presidential race, aiming to lead the country into ‘a new golden age of mass sacrifice and unmentionable horror’

If you thought Donald Trump in the White House was your worst US presidential election nightmare, think again: none other than HP Lovecraft’s slime-encrusted cosmic horror Cthulhu is running in the 2016 election.

But what do voters need to know on this Super Tuesday about the tentacled candidate who aims to blow open the two-party race? The aspiring leader has a usefully informative website for those interested. Here we learn that like the current Oval Office incumbent, Cthulhu – who is standing on the “eldritch horror” ticket – hails from an island in the Pacific. It’s not Hawaii, though: it’s R’lyeh, the lost sunken city where, according to Lovecraft, Cthulhu waits to take control of the world.

And there’s no point asking to see his passport … millennia-old Cthulhu predates such bona fides. In fact, he predates countries. And people. So why the US – and why now?

I tracked down his campaign manager Eminence Waite to find out. “His influence on US history is subtle but potent; from stock market crashes to rising global tensions. He has been a part of our nation from its inception,” Waite says. “His presidential campaign is about unleashing an unending wave of insanity. He has selected the US population as his chosen people and he will lead them to a new golden age of mass sacrifice and unmentionable horror.”

Loving Vincent: A beautiful tribute to Vincent van Gogh

Loving Vincent will be a totally hand-painted animated film tribute to the beloved painter.

Here's the website for the film.
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