Escape velocity on Phobos changes a lot depending on location

A new computer analysis of the shape of the gravitational field of the Martian moon Phobos suggests that the escape velocity varies significantly, depending on where you are on the moon’s surface.

Phobos is an odd duck among our solar system’s moons. It’s tiny (a fraction of a percent the size of our own moon) and is shaped like a potato; that weird shape draws gravity to different places, depending on where you are.

All these features make Phobos a challenge to travel on, researchers report in Advances in Space Research. In some places, moving any faster than 5 kilometers per hour would be enough to free you from the moon’s meager gravitational pull, sending you off into space where you’d likely be captured by Mars’s gravity and end up orbiting the Red Planet. The fastest you could travel anywhere on Phobos would be about 36 kilometers per hour, or a little faster than a golf cart, the team finds.

Obviously, this must be recognized for any mission trying to land and explore the moon.

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Rocket Lab raises an additional $140 million

Capitalism in space: Rocket Lab has raised an additional $140 million in investment capital following its successful first operational launch last week.

The company announced Nov. 15 that it closed a Series E funding round, led by existing investor Future Fund, an Australian sovereign wealth fund. Several other existing investors also joined the round, including Greenspring Associates, Khosla Ventures, Bessemer Venture Partners, DCVC (Data Collective), Promus Ventures and K1W1. One new investor, Accident Compensation Corporation of New Zealand, joined the round.

The Series E round comes after the company raised $75 million in a Series D round in March 2017. The company has now raised more than $288 million to date. Rocket Lab did not disclose the valuation of the latest round, but said it exceeded the “$1-billion-plus” valuation from its Series D round.

In the race to grab the smallsat market, Rocket Lab is far ahead of its nearest competitors, Virgin Orbit and Vector. If I had to rank them at this moment, I would say that Virgin Orbit is second with Vector third.

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Defense offers much lower $5 billion Space Force cost

The deputy defense secretary yesterday said that the cost for creating a Space Force should be around $5 billion, not $13 billion as proposed by the Air Force.

The cost to create President Trump’s Space Force could be lower than $5 billion and certainly will be in the single-digit billions, Deputy Defense Secretary Patrick Shanahan said at a briefing Thursday, pushing back against Air Force estimates that put the price tag at $13 billion or more.

Shanahan, the lead Pentagon official working on the Space Force, expressed confidence the project would come to fruition — even though Democrats taking over the House have opposed it and the White House has broadly ordered the Pentagon to cut costs.

It appears that he is proposing that the military avoid the creation of a full-fledged new branch of the military and simply reorganize its space bureaucracy into a single office. This would not require Congressional approval, and is also what the military has been considering for the last few years.

Five billion however for an office still seems an ungodly amount of money to me. But then, this is how corrupt Washington functions.

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Astronomers identify first progenitor star for Type 1C supernovae

Astronomers have for the first time identified a progenitor star for a Type 1C supernovae.

[The search for supernovae progenitor stars has found] a few pre-supernova stars. But the doomed stars for one class of supernova have eluded discovery: the hefty stars that explode as Type Ic supernovas. These stars, weighing more than 30 times our Sun’s mass, lose their hydrogen and helium layers before their cataclysmic death. Researchers thought they should be easy to find because they are big and bright. However, they have come up empty. Finally, in 2017, astronomers got lucky. A nearby star ended its life as a Type Ic supernova. Two teams of researchers pored through the archive of Hubble images to uncover the putative precursor star in pre-explosion photos taken in 2007. The supernova, catalogued as SN 2017ein, appeared near the center of the nearby spiral galaxy NGC 3938, located roughly 65 million light-years away.

An analysis of the candidate star’s colors shows that it is blue and extremely hot. Based on that assessment, both teams suggest two possibilities for the source’s identity. The progenitor could be a single star between 45 and 55 times more massive than our Sun. Another idea is that it could have been a binary-star system in which one of the stars weighs between 60 and 80 times our Sun’s mass and the other roughly 48 solar masses. In this latter scenario, the stars are orbiting closely and interact with each other. The more massive star is stripped of its hydrogen and helium layers by the close companion, and eventually explodes as a supernova.

As can be seen by the quote above, identifying the star that exploded still leaves much unknown, including whether the star is a single or a binary. Still, they finally have some idea what kind of star erupts in a Type IIC supernovae, which will help constrain the theories for explaining the cause of these explosions.

Note also that this identification will not be confirmed until the supernova itself completely fades in about two years. They might find when that happens that the candidate progenitor is still there, meaning it was not the progenitor of the supernova at all.

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SpaceX successfully launches Qatar communications satellite

Capitalism in space: SpaceX today successfully launched a communications satellite for Qatar.

The first stage, previously flown in July, successfully landed on their drone ship. They intend to fly it for an unprecedented third time in the very near future. With this launch SpaceX has tied its record for most launches in a year, 18, which is also the most ever in a single year by a private company.

The leaders in the 2018 launch race:

31 China
18 SpaceX
10 Russia
8 ULA
8 Europe (Arianespace)

China continues to lead the U.S. in the national rankings, 31 to 29.

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Sixty documented-as-false anti-Trump news stories

Link here. A review of the sources for these stories show them coming mostly from the usual liberal news sources, places like CNN, the New York Times, the Washington Post, MSNBC, etc. I especially like #48:

48. May 28, 2018: The New York Times’ Magazine editor-in-chief Jake Silverstein and CNN’s Hadas Gold shared a story with photos of immigrant children in cages as if they were new photos taken under the Trump administration. The article and photos were actually taken in 2014 under the Obama administration.

Even after it was clearly documented that the fenced facilities were established during the Obama administration and that the Trump administration was simply continuing Obama policy in this area, these news organizations actually ramped up their coverage to make it seem as if Trump was the person who created this policy.

Liberals might wonder why Trump’s support remains strong, and rail against his crude attacks on the liberal press, but the bottom line remains: What he has been saying about the liberal press is largely true. They have stopped doing real reporting and have instead allowed their opposition to a Republican president to turn into blind hatred.

Moreover, Trump’s crude attacks have been a response to the left’s own crudeness and dishonesty, something the left refuses to admit to. And until we see a introspective reassessment by the liberal press, the crude attacks from both sides are only going to get worse.

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India to attempt four more launches in 2018

The new colonial movement: In outlining the success of yesterday’s GSLV launch, the head of India’s space agency noted that they will attempt to complete four more launches before the end of the year.

Following the missions, Mr Sivan said, in January next, ISRO would launch the Chandrayaan-II mission (lunar lander) which will be the first operational mission of the GSLV-Mk III-vehicle.

Addressing reporters after the successful launch of the second developmental flight GSLV-MkIII-D2 carrying communication satellite GSAT-29, he said, “we have to achieve 10 missions before January.”

“That is six satellite missions as well as four launch vehicle missions. Definitely, the task in front of us is very huge,” he said.

According to him, after Wednesday’s flight, the heaviest launcher of India has completed its development flights and is entering into the operational group of launchers of ISRO, that is along with the PSLV (polar satellite launch vehicle) and GSLV.

Four launches in six weeks would require a launch every week and a half. IF ISRO can do this, they will demonstrate the ability to launch almost weekly, a capability that would place them close to becoming a world power in space.

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Scientists admit to many errors in ocean warming paper

The uncertainty of science: The scientists who wrote a much heralded paper a few weeks ago claiming that the oceans are retaining far more heat than previously believed have admitted that their paper has many errors that make its conclusions far more uncertain.

Scientists behind a major study that claimed the Earth’s oceans are warming faster than previously thought now say their work contained inadvertent errors that made their conclusions seem more certain than they actually are.

Two weeks after the high-profile study was published in the journal Nature, its authors have submitted corrections to the publication. The Scripps Institution of Oceanography, home to several of the researchers involved, also noted the problems in the scientists’ work and corrected a news release on its website, which previously had asserted that the study detailed how the Earth’s oceans “have absorbed 60 percent more heat than previously thought.”

“Unfortunately, we made mistakes here,” said Ralph Keeling, a climate scientist at Scripps, who was a co-author of the study. “I think the main lesson is that you work as fast as you can to fix mistakes when you find them.”

The central problem, according to Keeling, came in how the researchers dealt with the uncertainty in their measurements. As a result, the findings suffer from too much doubt to definitively support the paper’s conclusion about how much heat the oceans have absorbed over time. [emphasis mine]

To put it more bluntly, their conclusions are worthless, the data being too uncertain.

When this paper came out two weeks ago I looked at it, and found myself questioning its results. They seemed too certain. Moreover, their work was too perfect for confirming the theory that the oceans are retaining more heat and thus causing the pause in global warming that no global warming model predicted. It fit the model of most climate research these days, unreliable and unconvincing, which is why I did not post it on Behind the Black.

Now, only two weeks later, we find the researchers backing off from their certain conclusions. If anything is a perfect demonstration of confirmation bias, this story is it. These global warming scientists want desperately to prove their theories, and since their models haven’t been working they are desperately searching everywhere they can for explanations. In this case that search led them astray.

The truth is that maybe the climate field should take a step back and reconsider its entire assumptions about carbon dioxide and global warming. They might actually end up doing better science, and thus do a better job at getting us closer to the truth.

A side note: That this paper passed peer review, and was strongly touted by the media and the science community, illustrates once again how much that media and science community has allowed its biases to cloud its vision. This paper should never have been published with these errors. Period.

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Scientists discover giant impact crater buried under Greenland ice

Scientists have discovered the existence of a giant impact crater buried under the Greenland ice.

An international team of researchers, including a NASA glaciologist, has discovered a large meteorite impact crater hiding beneath more than a half-mile of ice in northwest Greenland. The crater — the first of any size found under the Greenland ice sheet — is one of the 25 largest impact craters on Earth, measuring roughly 1,000 feet deep and more than 19 miles in diameter, an area slightly larger than that inside Washington’s Capital Beltway.

They think, based on the data, that this crater is very young, one of the youngest known on Earth. At the most is is no more than 3 million years old.

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Null result from Spitzer suggests Oumuamua was small

The uncertainty of science: The inability of the infrared Spitzer Space Telescope to detect the interstellar object Oumuamua as it exited the solar system suggests the object is small.

The fact that ‘Oumuamua was too faint for Spitzer to detect sets a limit on the object’s total surface area. However, since the non-detection can’t be used to infer shape, the size limits are presented as what ‘Oumuamua’s diameter would be if it were spherical. Using three separate models that make slightly different assumptions about the object’s composition, Spitzer’s non-detection limited ‘Oumuamua’s “spherical diameter” to 1,440 feet (440 meters), 460 feet (140 meters) or perhaps as little as 320 feet (100 meters). The wide range of results stems from the assumptions about ‘Oumuamua’s composition, which influences how visible (or faint) it would appear to Spitzer were it a particular size.

The new study also suggests that ‘Oumuamua may be up to 10 times more reflective than the comets that reside in our solar system – a surprising result, according to the paper’s authors.

These results fit the models that explain Oumuamua’s fluctuations in speed as caused by the out gassing of material, like a comet. They also do not contradict the recent hypothesis that the object might have been an alien-built light sail.

The simple fact is that we do not have enough data to confirm any of these theories.

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