How the Earth gave the Moon a lemon shape

9:36 am

Scientists have found that the Earth’s gravity combined with the Moon’s rotation forced the satellite to become “lemon-shaped.”

As the Moon solidified, its rotation caused it to elongate along its polar axis. But because the length of the Moon’s rotation was the same as its orbit, with one hemisphere always facing the Earth, the tidal force of the Earth’s gravity then pulled at the center, distorting the Moon’s shape so that one hemisphere bulged Earthward.

This theory is not new, but these new calculations are more robust, lending greater weight to it.

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The first lunar close-up

9:28 am

Fifty years ago tomorrow Ranger 7 took the first close-up images of the Moon, just before the spacecraft crashed onto the surface.

“It was like looking at a soft quilt or something, no jagged edges on anything,” muses Jim Burke, as if he’s describing something every school kid hasn’t seen a hundred times. “It looked like fresh snow in a way, except it was grey instead of white.”

At the time—50 years ago tomorrow—Burke was one of the first people on Earth to see what the surface of the Moon looks like up close. Early on the morning of July 31, 1964, he joined his colleagues in poring over a series of printed photographs, the pockmarked Moon getting closer and closer until one final blurred image marked the moment when Ranger 7 impacted the surface, making its own brand-new crater. A stripe of static along one side of that last photo indicated the interruption of the final transmission.

The article details the frustrating history of the Ranger program, with the first six attempts all failing. Ranger 7 succeeded, however, working so well that the last image actually got truncated at impact. The full set of images revealed the surprising cratered history of the Moon, with the impact rate of large to small craters far more complex than expected.

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Genesis cover

On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.

 

The print edition can be purchased at Amazon or any other book seller. If you want an autographed copy the price is $60 for the hardback and $45 for the paperback, plus $8 shipping for each. Go here for purchasing details. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.


The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
 

"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News

The early bombardment of the Earth

9:04 am

Using computer models based on the Moon’s crater record, scientists have developed a simulation of the great early bombardment of the Earth around 4 billion years ago.

The model suggests that the biggest asteroids to hit Earth would have been as large as 3,000 kilometres across. Between one and four would have been 1,000 kilometres wide or larger, it predicts, with a total of three to seven exceeding 500 kilometres in width. The most recent of these would have hit around 4.2–4.3 billion years ago.

In comparison with Earth’s mass, the amount of rock hitting the planet would have been tiny. But it would have had an enormous effect on Earth’s surface, says Marchi. A 10-kilometre-wide asteroid was enough to kill the dinosaurs, and studies4 show that one 500 kilometres across would vaporize all of the planet’s oceans. “At 1,000 kilometres, the effects would be so wide the planet would probably be completely resurfaced with material from the mantle,” he says.

More here, including animated gifs showing this bombardment unfold.

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Conscious Choice cover

Now available in hardback and paperback as well as ebook!

 

From the press release: In this ground-breaking new history of early America, historian Robert Zimmerman not only exposes the lie behind The New York Times 1619 Project that falsely claims slavery is central to the history of the United States, he also provides profound lessons about the nature of human societies, lessons important for Americans today as well as for all future settlers on Mars and elsewhere in space.

 
Conscious Choice: The origins of slavery in America and why it matters today and for our future in outer space, is a riveting page-turning story that documents how slavery slowly became pervasive in the southern British colonies of North America, colonies founded by a people and culture that not only did not allow slavery but in every way were hostile to the practice.  
Conscious Choice does more however. In telling the tragic history of the Virginia colony and the rise of slavery there, Zimmerman lays out the proper path for creating healthy societies in places like the Moon and Mars.

 

“Zimmerman’s ground-breaking history provides every future generation the basic framework for establishing new societies on other worlds. We would be wise to heed what he says.” —Robert Zubrin, founder of the Mars Society.

 

All editions are available at Amazon, Barnes & Noble, and all book vendors, with the ebook priced at $5.99 before discount. All editions can also be purchased direct from the ebook publisher, ebookit, in which case you don't support the big tech companies and the author gets a bigger cut much sooner.

 

Autographed printed copies are also available at discount directly from the author (hardback $29.95; paperback $14.95; Shipping cost for either: $6.00). Just send an email to zimmerman @ nasw dot org.

Clarence White & Roland White – I Am A Pilgram/Soldiers Joy

6:01 pm

An evening pause: Performed live on Bob Baxter’s “Guitar Workshop” in 1973. Hat tip to jwing, who wrote the following when he sent me the link:

Clarence was instrumental in making flat-picking guitar a lead solo instrument in bluegrass, along with Doc Watson. He played as a session musician for many groups in the 60’s such as the Everly Brothers and The Monkees. Later he became the lead guitarist for Roger McGuinn’s Byrds. He developed the B-string bender invention that you can hear on the Eagles’ song “Take It Easy.” Sadly, in 1973 while packing up the band’s van after a late night gig he was hit by a drunk driver and was killed. A huge loss to music. This video was recorded in LA only a few months before that fateful night. Enjoy a true virtuoso.

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Leaving Earth cover

Leaving Earth: Space Stations, Rival Superpowers, and the Quest for Interplanetary Travel, can be purchased as an ebook everywhere for only $3.99 (before discount) at amazon, Barnes & Noble, all ebook vendors, or direct from my ebook publisher, ebookit.

 

If you buy it from ebookit you don't support the big oppressive tech companies and I get a bigger cut much sooner.

 

Winner of the 2003 Eugene M. Emme Award of the American Astronautical Society.

 
"Leaving Earth is one of the best and certainly the most comprehensive summary of our drive into space that I have ever read. It will be invaluable to future scholars because it will tell them how the next chapter of human history opened." -- Arthur C. Clarke

Chinese anti-satellite test?

3:28 pm

The U.S. State department is claiming that China completed a “non-destructive” anti-satellite test last week.

The State department also demanded that China refrain from further such actions.

China in turn said that the test was for a a ballistic missile defense system. According to these Chinese reports, the test was of a land-based missile designed to intercept an incoming rocket, much like Israel’s Iron Dome and the U.S. SDI systems. Such a system, however, is in many ways indistinguishable from an anti-sat system. In fact, the U.S. military proved that by firing a missile that successfully destroyed an orbiting satellite several years ago.

In the case of last week’s Chinese test, the interceptor did not apparently impact anything but instead demonstrated its ability to hit a prearranged simulated point in space.

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New emails reveal Lois Lerner’s hatred of conservatives

9:13 am

Working for the Democratic Party: In newly revealed emails, Lois Lerner refers to Obama’s conservative opponents as “–holes” and “terRorists”.

In that Nov. 9, 2012 email, Lerner further suggests that conservatives will ruin the country: “So we don’t need to worry about alien teRrorists (sic). It’s our own crazies that will take us down,” she wrote.

The evidence also shows that Lerner used her private email account to conduct official IRS business, while also clearly favoring liberal organizations.

I wonder what we would find if those lost emails could turn up?

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ExoMars will likely miss 2018 launch date

9:06 am

Because of technical and financial issues the European/Russian ExoMars rover mission is expected to miss its 2018 launch window.

The main reason for the delay would be the ExoMars’ brand-new landing system, which is designed to safely take the rover through a fiery descent in the Martian atmosphere and then softly land it on the surface of the Red Planet.

In addition to its late development start, the landing system has a complicated share of responsibilities between Russia and Europe, which greatly slows down the work. For example, the overall landing system is being developed by NPO Lavochkin in Moscow, while its parachute system will be provided by Europe. Many other aspects of the mission are similarly intertwined.

To further complicate matters, NPO Lavochkin, which traditionally builds all Russian planetary probes, but also some of the highly classified military satellites, is notorious for its Soviet-style secrecy. As a result, it is harder for the two sides to coordinate the work, Europeans sources said. Finally, the translation of documents between Russian and English further delays the work on the project.

The program is also significantly over budget.

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A new cheap rocket company

8:43 am

The competition heats up: A New Zealand company says it is building a rocket capable of launching cubesats into orbit for only $5 million.

Rocket Lab says it is building a carbon-composited launch vehicle –named Electron—which will send small satellites into earth’s orbit for five million U.S. dollars. The U.S. company, which is building the vehicle in New Zealand, expects the first to be ready next year and already has committed to its first 30 launch slots.

Though their low cost will once again increase the space launch customer base, they are not really in competition with any of the big players, who don’t really make their money launching cubesats. Instead, by focusing on the cubesat market, Rocket Lab is aimed at providing launch services to a niche that has, up until now, had no real launch services. If a university or small company wanted to launch a cubesat., they had to piggyback on a large launch.

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Last ATV launched to ISS

8:34 am

Arianespace today successfully launched the last European cargo ship to ISS.

After doing some flight tests in orbit and in conjunction with ISS, the docking will occur on August 12.

After this flight the Russian Progress freighter will be the only spacecraft with engines capable of changing the station’s orbit. It will also be the only spacecraft capable of refueling the engines on ISS’s Russian modules.

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The Milky Way shrinks

9:49 pm

The uncertainty of science: New research by astronomers suggests that the Milky Way is about half as massive as previously estimated.

In the sixties I remember astronomers claiming that the Milky Way was twice as big as Andromeda. Then it was considered half as big. Most recently it was considered about the same size. This new research makes it half as big as Andromeda again.

In other words, the data is very uncertain, and the scientists really don’t have a good handle on it. None of these conclusions should be taken very seriously. All we really know at this point is that the Milky Way and Andromeda are approximately comparable.

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SpaceShipTwo flies again

9:44 pm

The competition heats up: For the first time in six months SpaceShipTwo completed a test flight today.

The article above is from NBC, which also has a deal with Virgin Galactic to televise the first commercial flight. It is thus in their interest to promote the spacecraft and company. The following two sentences from the article however clearly confirm every rumor we have heard about the ship in the past year, that they needed to replace or completely refit the engine and that the resulting thrust might not be enough to get the ship to 100 kilometers or 62 miles:

In January, SpaceShipTwo blasted off for a powered test and sailed through a follow-up glide flight, but then it went into the shop for rocket refitting. It’s expected to go through a series of glide flights and powered flights that eventually rise beyond the boundary of outer space (50 miles or 100 kilometers in altitude, depending on who’s counting).

Hopefully this test flight indicates that they have installed the new engine and are now beginning flight tests with equipment that will actually get the ship into space.

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Jews attacked in Germany

3:58 pm

The evil returns: In Germany a synagogue is firebombed and a rabbi gets death threats merely because they are Jewish.

As one commenter at the website above explained when another commenter asked for an explanation of anti-semitism, “An example of anti-Semitism is where people in the middle east are shooting at each other and an uninvolved Jewish man in Wuppertal gets death threats because of it.”

Reading the comments and the amount of childish hate that exudes from too many of them will certainly depress you.

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ISEE-3 engine restart fails but the private effort continues

11:57 am

After numerous tries, the private effort to put ISEE-3 back into its original orbit has failed.

We have completely accomplished all of our original goals except for one: firing the ISEE-3 propulsion system in a sufficient fashion to alter its trajectory. We did operate the propulsion system briefly so as to correct the spin of the spacecraft, and to start the trajectory correction maneuver. The propulsion system works fine. The problem is that there is no longer any Nitrogen pressurant left in its tanks to allow it to work.

36 years and more than 30 billion miles have taken its toll on the spacecraft’s propulsion system. We have exhausted every option to bring the engines online so as to conduct the correction maneuver required to place it in its planned orbit. Without the pressurant it just won’t work.

Have they given up? No! Though the spacecraft will remain in a solar orbit where maintaining communications will be difficult if not impossible, they are going to try anyway, and are even going to run another crowd-sourcing campaign to finance it.

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Black bigots in California

10:54 am

Black leaders in Fresno, California want to stop the hiring of a teacher merely because his skin color happens to be white.

On Monday morning, a small band of activists showed up in front of the sparkling new school at the corner of Martin Luther King Jr. Boulevard and Church Avenue. The local press was also there. “We’re just saying what the community wants,” said Rev. Karen Crozier, one of the activists. “We didn’t fight for a white male or female teacher to educate our babies.” Crozier, who appears to be a professor at Fresno Pacific Biblical Seminary, also suggested that a white person cannot teach minority children in this instance because of racism.

Sometimes the bigotry and blindness of people just leaves me speechless.

In related news, the organizer of a “gay” job fair is outraged that non-gays keep showing up there looking for jobs.

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Gaia commissioning complete

9:47 am

After several months of in-orbit analysis, engineers have declared the European space telescope Gaia ready to begin research.

There have been several issues that had raised concerns, but from the article it sounds as if the engineers have either corrected the problems or have found ways to overcome or mitigate them.

Gaia will measure the movement and location of a billion stars, allowing astronomers to map the Milky Way better than ever before.

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Congress restores most VA bonuses

9:39 am

After the House voted 421-0 in June to eliminate all bonuses at the Veterans Administration in response to the scandals there, a compromise bill with the Senate has restored most of those bonuses.

The compromise bill announced Monday by the chairmen of the House and Senate Veterans’ Affairs Committees says VA bonuses will be capped at $360 million annually for the next ten years. But that cap is just 10 percent below the $400 million in bonuses the VA has distributed in recent fiscal years, and will allow up to $3.6 billion in bonuses to be awarded over the next decade.

“In each of fiscal years 2015 through 2024, the Secretary of Veterans Affairs shall ensure that the aggregate amount of awards and bonuses paid by the Secretary in a fiscal year… does not exceed $360,000,000,” the bill says. A description of the bill adds that members expect the VA to implement this cap in a way that does not “disproportionately impact lower-wage employees,” although the legislation itself does not include any restriction on how to award the money.

More evidence that our elected officials don’t represent us, but the employees of the government instead.

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World War I underground

9:28 am

Visiting the underground tunnels of World War I.

At the height of the underground war, in 1916, British tunneling units detonated some 750 mines along their hundred-mile sector of the front; the Germans responded with nearly 700 charges of their own. Hills and ridges that provided vital lookout points became riddled like Swiss cheese, while the biggest mines blew out huge craters that still scar the landscape to this day. Even a single small mine could wreak havoc: In the tunnel complex we crawled into, a charge set off by the Germans on January 26, 1915, killed 26 French infantrymen and wounded 22 more.

But the underground war was not confined to narrow tunnels. Beneath Picardy’s fields and forests are centuries-old abandoned quarries, some of which could shelter thousands of troops. On a misty morning we explore one such site, located along a cliff edge overlooking the Aisne Valley. We’re led there by the owner of the ancestral property, which we agree not to name to protect the quarry from vandals.

Read the whole thing. It reminds me of my experience exploring the mines under Tombstone. These tunnels provide an archeological window into the history of the first World War.

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Amazon’s 3D printshop opens

9:20 am

The competition heats up: Amazon has opened its first 3D-print shop, where customers can buy 3D printed products.

The store has launched with more than 200 print-on-demand designs. Users can customize items like earrings, pendants, rings and bobble head dolls using a special widget, before having the item 3D-printed and delivered. …

Although users of the store cannot upload and print their own designs, it is, as mentioned, possible to customize some of the available designs. Amazon has built a customization engine into the store, allowing for very simple changes to an item’s design, or more wholesale changes. Interactive 3D preview functionality is also provided, with which users can rotate an object and view it from any angle.

What does this story have to do with space exploration? Well, it marks the beginning of a major revolution in manufacturing that will change everything. And since 3D printing is going to be an essential need for future space explorers, having this new industry prosper and grow can only speed up the exploration and settlement of the solar system.

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Venus Express is alive

9:03 am

After diving into Venus’s atmosphere on an aerobraking test that could have destroyed the spacecraft, the European probe Venus Express has now successfully used its last bits of fuel to raise its orbit back to research height.

Its present orbit will probably decay sometime in December, when the spacecraft will burn up in the atmosphere. However, the scientists running the mission though that was likely to happen during the aerobraking maneuver. Instead, Venus Express is giving them about another half year of research.

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Planet of geysers

2:54 pm

Using Cassini data assembled over the past seven years, scientists have now identified 101 distinct geysers erupting on the surface of the Saturn’s moon Enceladus.

Over a period of almost seven years, Cassini’s cameras surveyed the south polar terrain of the small moon, a unique geological basin renowned for its four prominent “tiger stripe” fractures and the geysers of tiny icy particles and water vapor first sighted there nearly 10 years ago. The result of the survey is a map of 101 geysers, each erupting from one of the tiger stripe fractures, and the discovery that individual geysers are coincident with small hot spots. These relationships pointed the way to the geysers’ origin.

The really important discovery here however is this:
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