Year: 2021

Astronomers: If there are artificial Dyson spheres out there, we can detect them

8:55 am

In a preprint science paper published on October 26, 2021, astronomers review the impact a Dyson sphere might have on its central star and conclude that modern astronomical instruments should be able to identify these changes. From the abstract:

The search for signs of extraterrestrial technology, or technosignatures, includes the search for objects which collect starlight for some technological use, such as those composing a Dyson sphere. These searches typically account for a star’s light and some blackbody temperature for the surrounding structure. However, such a structure inevitably returns some light back to the surface of its star, either from direct reflection or thermal re-emission. In this work, we explore how this feedback may affect the structure and evolution of stars, and when such feedback may affect observations. We find that in general this returned light can cause stars to expand and cool. Our MESA models show that this energy is only transported toward a star’s core effectively by convection, so low mass stars are strongly affected, while higher mass stars with radiative exteriors are not. Ultimately, the effect only has significant observational consequences for spheres with very high temperatures (much higher than the often assumed ~300 K) and/or high specular reflectivity. Lastly, we produce color-magnitude diagrams of combined star-Dyson sphere systems for a wide array of possible configurations.

A plain-language description of the paper can be found here, which summarizes this work as follows:

This study shows that Dyson spheres can result in measurable changes to stellar properties. Megastructures have long been confined to science fiction, imagination and certain video games. However, if there are indeed Dyson spheres out there waiting to be found, we could soon be in a position to find them.

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Enrollment decline continues in urban public schools

9:21 am

Some good news: In reporting today that the Chicago public school system this year lost 10,000 students, the Associated Press story also said this:

The enrollment decline, which has been happening each year for the past decade, comes as other big city districts including New York and Los Angeles have seen enrollment declines this year as well. … The enrollment drop this academic year is due to students moving elsewhere, going to private schools or homeschooling, according to recent district data.

The story also noted that this declines appears to be occurring among all ethnic groups, since the school demographics remained unchanged.

Finally, being the Associated Press and thus married to supporting governments run by Democrats, the story had to allow the final word to the city’s Democratic Party mayor as well as the unions that have routinely backed her:

Mayor Lori Lightfoot called the drop a “minor miracle,” saying she was surprised enrollment didn’t decline even more considering the COVID-19 pandemic. “We had to quickly transition to remote learning. We know that didn’t work for a lot of families. There’s been a lot of challenges and struggles that have been revealed throughout the course of this pandemic that hit our most vulnerable residents the hardest, many of whom” have children attending CPS, Lightfoot said.

Meanwhile, the Chicago Teachers Union blamed underfunded schools, particularly in largely Black and Hispanic neighborhoods, as a major driver.

That parents might have finally gotten disgusted with the government’s utter failure to teach reading, writing, or arithmetic does not occur to these political geniuses. Nor does it occur to them that their passion for forcing masks and racial indoctrination on little children might have also contributed to the decline in enrollment.

No, for leftists their failures are always explained by either a lack of funding or circumstances beyond their control. Give us more money and all will be well! We promise!

It appears however that an increasing number of parents are no longer buying these arguments. Thank goodness.

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Dragon crew launch to ISS delayed due to weather

10:57 pm

The early morning launch on October 31st of the next manned flight of SpaceX’s Endurance capsule to ISS, has been delayed because of poor weather downrange from the launch site.

The bad weather could have interfered with recovery operations should a launch abort had been necessary and the capsule was forced to land in the Atlantic.

The launch has now been rescheduled for 1:10 am (Eastern) on November 3rd.

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Hubble in safe mode again

10:50 pm

According to NASA’s Twitter feed for the Hubble Space Telescope, it went into safe mode earlier this week because of “issues with internal communications.”

Hubble’s science instruments went into safe mode on Monday after experiencing synchronization issues with internal spacecraft communications. Science observations have been temporarily suspended while the team investigates the issue. The instruments remain in good health.

Much of the press is using that lovely buzzword of bureaucrats, calling this a “glitch.” The goal of that word is to make the problem seem minor and no big deal.

It can’t be minor and no big deal however if the telescope shut down six days ago and remains out of service. This is not a “glitch.” This is a serious issue that is taking time to resolve.

Furthermore, I get more concerned when no further information is provided. As far as I can so far find, the quote above is the only information NASA has released. And that information is remarkably vague and uninformative.

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The Haunting

6:01 pm

An evening pause: For the Halloween weekend, one of Hollywood’s best ghost films, Robert Wise’s The Haunting (1963), based on a short story by Shirley Jackson.

No blood. No gore. No violence. Only an overwhelming sense of dread and fear, evoked by brilliant filmmaking.

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ABL leases space at Port of Los Angeles

2:58 pm

Capitalism in space: The rocket startup ABL has now leased space at the Port of Los Angeles for “spacecraft processing” and cargo shipment.

Included in the five-year lease is a 25,000-square-foot integration and payload processing facility, 20,000-square-foot warehouse space, and a 13,000-square-foot office space. The location, previously occupied by rocket launching ship company Sea Launch, will be used by ABL for a range of operations including vehicle processing, payload integration, and maritime operations supporting the company’s launch facilities around the world.

This deal comes on top of ABL’s announcement earlier this week that it has raised an addition $200 million in investment capital, and is planning its first launch in mid-December.

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Holes in snowy ice on Mars?

1:30 pm

Holes in snowy ice on Mars?
Click for full image.

Cool image time! Today we return to the regions surrounding Milankovic Crater in the high northern latitudes of Mars. The photo to the right, cropped and reduced to post here, was taken on June 1, 2021 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows a spray of impact craters where the bolides apparently landed in relatively soft material. The location itself is about 10 miles to the southeast of the 74-mile-wide crater, and sits within its rim ejecta blanket.

The label for the image says this is showing “crater modification,” which suggests that the rimless nature of these craters became so after their creation. This location, at 54 north latitude, is in a region of Mars where scientists have found a lot of evidence of near surface ice. For example, within Mikankovic Crater itself they have identified numerous scarps with clearly seen pure ice layers.

If ice is close to the surface here, then the ground could be like soft snow on Earth, especially because Mars’ lighter gravity would not compress that ice as much. Think about what happens when you toss pebbles into soft snow. They fall through, and leave behind holes not unlike the ones we see in this picture. Later, sunlight would begin to modify the holes so that their edges grow outward, once again exactly as we see here.

The overview map below as always gives some context, which in this case has less to do with Mars but with Elon Musk and Starship.
» Read more

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Today’s blacklisted American: Surgeon fired after telling school board its mask mandate on kids was wrong

11:33 am

Jeffrey Horak, speaking at school board against masks
Jeffrey Horak, speaking in opposition to mask mandates
at Fergus Falls school board on October 11th.

They’re coming for you next: Jeffrey Horak, a surgeon in Minnesota with 32 years of experience, was fired by his hospital just nine days after he publicly told a school board it had no business mandating masks on little children, that such a decision belonged solely to the parents.

When asked why Horak was so suddenly fired, officials at the hospital provided the typical weasel-worded answers designed to dodge responsibility.

A spokesperson for Lake Region Healthcare deferred questions to Lake Region Medical Group, saying that the “Medical Group Board made the decision about discontinuing Dr. Horak’s practice, not LRH.”

Dr. Greg Smith, the president of the Medical Group Board, said they made the “decision to discontinue Dr. Jeff Horak’s employment contract after a thorough review process.”

“The reasons for Dr. Horak’s separation are a confidential matter,” Dr. Smith said in a statement provided to Fox News on Tuesday. “To be clear, this was a decision that was made by Dr. Horak’s peers who serve on the Medical Group Board, not by Lake Region Healthcare, the community-based hospital where Dr. Horak practiced General Surgery.”

» Read more

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VC of Joint Chiefs: Not one, not two, but “hundreds” of Chinese hypersonic tests!

9:11 am

If I did not have confirmation of my skepticism about the claims by the military and anonymous sources that China this summer completed a successful hypersonic test flight, I have it now.

Today the Vice Chairman of the Joint Chiefs of Staff, Gen. John Hyten, made a speech demanding that the military stop building expensive gold-plated satellites and emulate SpaceX’s methods of frequent testing and quick development.

Hyten has been very correctly pushing for this change in strategy for years. However, in his remarks he said this:

China, he said, has performed “hundreds” of tests of hypersonic weapons in the last five years, compared to nine the United States has performed.

…[He also] implied this morning, but did not state categorically, that China has built and tested what appears to be a Fractional Orbital Bombardment System (FOBS).

FOBS technology is not new, but Hyten described it “as highly destabilizing.” And China’s reported use of a nuclear-capable hypersonic glide vehicle (HGV) as the pointy end of the stick would be a twist. The Soviets deployed a FOBS — which combines a low-flying missile and nuclear warhead that reaches Low Earth Orbit, but does not remain in space for a full turn about the Earth — from 1969 to 1983. China began an effort in the early 1970s, but suffered test failures with its launcher, and gave up. [emphasis mine]

As I say, Hyten’s goals — fast testing, fast development, and not fearing failure — are all correct and laudable. But to suddenly turn a questionable story about a possible single successful Chinese hypersonic test flight, based entirely on anonymous sources, into “hundreds” of flights, strongly confirms to me that the original story was planted by the military to create fear in Congress and the public so that both would eagerly give the military more money.

The result will be that Hyten won’t get what he really wants. His use of exaggeration and possible disinformation will only cause Congress to balloon the military’s budget for new programs, which will then be used to feed the Pentagon’s insatiable appetite for endless and slow-moving test programs that only function as jobs programs, the very thing Hyten rails against.

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Drop in aviation during COVID lockdowns caused no change in high cirrus clouds, contrary to predictions of climate models

11:06 pm

The uncertainty of climate science: In the twenty-five years since I became a science journalist, I cannot count the number of high profile press releases and scientific papers that I’ve read claiming that the increase in aviation and the resulting contrails from airplanes was going to be a major contributor to human-caused global warming. According to the models, the increase in contrails was increasing the high altitude cirrus cover, and thus in a variety of ways acting to warm the planet.

Well, a paper just published in Geophysical Research Letters took a look at the effect the sudden and almost complete cessation of aviation during the 2020 COVID lockdowns had on high altitude cirrus clouds. If the models were right, the lack of air traffic should have caused a reduction in cirrus clouds, thus demonstrating the models were correct.

The models were wrong, once again. From the abstract:

We find that, despite the very large reduction in air traffic, neither cirrus cover nor temperature ranges changed by enough to be detectable relative to the year-to-year variability of natural cirrus. Comparing the satellite observations to previous model-simulated aviation cirrus, we determine that any aviation-induced change in cirrus would have a much smaller magnitude than would be inferred from climate model simulations. These results suggest that the warming effect of cirrus clouds produced by aircraft may be smaller than previously believed. [emphasis mine]

In other words, air traffic apparently has no impact on the high altitude cloud cover. The models that said this traffic was a contributor to global warming were 100% wrong. It apparently is not.

Of course, there remains some uncertainty even with this result, as it is for only one year. The effect of air traffic on clouds could have been disguised in 2020 by the natural fluctuations normally seen from year to year, though the paper’s authors think not.

Assuming this data is confirmed, the authors also concede that the plans to mitigate contrails by rerouting planes so that they do not all fly along the same routes could be very counter-productive. It will cause those detours to burn more fossil fuels, while changing nothing in the cloud cover in the upper atmosphere.

Ah, the law or unintended consequences once again rears its ugly head. Too bad global warming activists never seem to admit it exists, even though it constantly bites them in the rear, time after time after time after time after time….

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Solid dry ice in Moon’s permanently shadowed craters?

10:30 pm

Stable dry ice at Moon's south pole
Click for full figure.

Using eleven years of data from Lunar Reconnaissance Orbiter (LRO), scientists think they have identified small areas in the Moon’s permanently shadowed interiors of some polar craters where the temperatures are always cold enough for dry ice (solid carbon dioxide) to be stable.

The map to the right, cropped and reduced to post here, is Figure 2 of the paper. It shows the areas at the south pole where stable dry ice is thought possible. The darker blue/purple are colder and thus are expected to have less sublimation. From the abstract:

Carbon-bearing species would be essential for sustained robotic or human presence on the Moon, for use in rocket fuel and biological materials. Various volatiles can be cold-trapped in permanently shadowed craters near the lunar poles. The existence of carbon dioxide cold traps has previously been surmised, but the required temperatures are near the lowest surface temperatures that have been reliably measured. Extensive and improved analysis of 11 years of orbital surface temperature measurements establishes the existence of carbon dioxide cold traps on the Moon, which potentially host high concentrations of solid carbon dioxide. Large CO2 cold traps are rare, however, and the geographic concentration of the resource will have policy implications. [emphasis mine]

The paper also adds in its conclusion that these regions are likely going to be of high value, and will thus likely be prime settlement and mining targets by everyone. As they note, “That this resource is highly concentrated geographically has implications for the governance of the lunar surface.”

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