Scientists: Betelgeuse dimmed because of giant dark spot on surface

The uncertainty of science: A new study by scientists in China now proposes that the dimming of the red giant star Betelgeuse in 2019-2020 was because of a giant dark and cold spot on its surface.

When Betelgeuse was at its dimmest on Jan. 31, 2020, its effective temperature — meaning, the temperature calculated from its emitted radiation — was measured at 3,476 degrees Kelvin (about 5,800 degrees Fahrenheit or 3,200 degrees Celsius.)

But once the star was back to a normal luminosity, measurements indicated an almost 5% temperature rise to 3,646 Kelvin (roughly 6,100 F or 3,370 degrees C.)

…[T]he astronomers … concluded it is unlikely the entire surface cooled temporarily by that amount. Rather, it must have been a sunspot — or rather, a “star spot” — blocking some of Betelgeuse’s radiation from escaping, they said.

This new hypothesis aligns partly with others that say it was a combination of a dark spot and intevening dust that caused the dimming.

None of these hypotheses however “solve” the mystery. Too little concrete information exists at present to do that.

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Perseverance’s first sample grab fails

Perseverance's first core sample drill location
Click for full image.

The first attempt by the Mars rover Perseverance to obtain a core sample has apparently failed.

The failure does not appear to be technical. All the hardware appears to have worked. When they inspected the interior of the hollow core drill however no sample was seen inside.

“The sampling process is autonomous from beginning to end,” said Jessica Samuels, the surface mission manager for Perseverance at NASA’s Jet Propulsion Laboratory in Southern California. “One of the steps that occurs after placing a probe into the collection tube is to measure the volume of the sample. The probe did not encounter the expected resistance that would be there if a sample were inside the tube.”

…”The initial thinking is that the empty tube is more likely a result of the rock target not reacting the way we expected during coring, and less likely a hardware issue with the Sampling and Caching System,” said Jennifer Trosper, project manager for Perseverance at JPL. “Over the next few days, the team will be spending more time analyzing the data we have, and also acquiring some additional diagnostic data to support understanding the root cause for the empty tube.” [emphasis mine]

Do the highlighted words remind you of anything? They do for me. The first thing I thought of when I read this was the drilling mole for InSight’s heat sensor. It failed in its effort to drill into the Martian surface because the nature of the Martian soil was different than expected. It was too structurally weak, and would break up into soft dust rather than hold together to hold the mole in place.

In the case of Perseverance, it appears right now (though this is not confirmed) that the drill successfully drilled into the ground, with its core filling with material, but when the core was retracted, that material simply fell out, as if it was too structurally weak to maintain itself inside the core.

The photo above of the drill hole and its thick pile of dust appears to support this hypothesis. Even though they drilled into what looked like bedrock the act of drilling fragmented that bedrock apart.

I am speculating based on limited information, so I am likely wrong. For example, the drill certainly has sensors to detect the density and structural strength of the rock it is drilling into. The engineers will check those numbers during drilling. If the rock doesn’t appear dense enough or structurally strong enough for a core sample, I would expect them to pick a different spot.

If true however it means that obtaining core samples at many locations in Jezero Crater will simply not be possible. This does not mean no samples will be obtained, because there are definitely places on Mars where the ground’s structure is solid enough for this method to work. Curiosity definitely found this to be true, when if found several places on Vera Rubin Ridge where its drill didn’t have the strength to penetrate the rock.

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Having an off day

To my readers: This is one of those days where I just cannot get up the oomph to write. First, I am becoming bored by my daily “Today’s blacklisted American” column. It is not that the number of people being ruined and harmed by the oppressive thugs of the left has dropped, it is that I am finding that people are becoming desensitized to the oppression. I get the impression that my posts are being skimmed or ignored, because they are merely repeating the same story over and over again.

“Oh, yeah, big deal, another person lost their job because they dared to express an opinion. Call me when something new happens.”

Such a situation I find so depressing words can’t express it. Makes it very hard to work.

Second, I have a bunch of new cool images to post, but I am either waiting for answers from scientists before posting, or I don’t have the mental energy today to work up a post. Sorry. I think I simply need a real day off.

Unless I get energerized later today, you all will simply have to wait until I return in full force on Monday (though if something exciting pops up on the weekend it might get my writing juices flowing sooner).

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The trials and tribulations of Blue Origin’s BE-4 engine

Link here. The article tries to provide some explanations for the delays at Blue Origin that have put the BE-4 engine years behind schedule.

The first and most important fact gleaned from the article is that flightworthy versions of this engine will not be ready this summer as promised, and will likely not get delivered to ULA for its Vulcan rocket before the end of the year, causing its inaugural launch to be delayed to the second half of ’22. This also means that Blue Origin’s own orbital rocket, New Glenn, will likely not launch until late next year, at the earliest.

Moreover, the engines that Blue Origin will deliver to ULA will not be fully tested, and might require replacement if tests on other engines reveal more problems.

The article’s most important revelation about the delays however is this:

One of the most persistent problems, sources said, is that the BE-4 engine testing and development program has been relatively “hardware poor” in recent years. Effectively, this means that the factory in Washington has not had enough components to build development engines, and this has led to extended periods during which no testing has occurred on the stands in Texas.

It was surprising to hear this because back in the spring of 2017 Blue Origin stated publicly that its development program was hardware rich. After arriving as CEO in late 2017, however, [Bob] Smith appears to have focused more on a substantial reorganization of Blue Origin’s leadership rather than hardware development. Other programs were prioritized, too, so the BE-4 team did not get all the resources and freedom it needed to proceed at full throttle. [emphasis mine]

To put it more bluntly, Smith decided it was more important to rearrange the deck chairs rather than launch lifeboats into the water. As a result, Blue Origin has essentially wasted the last four-plus years.

There are signs that the company has changed course away from Smith’s focus, but we shall have to wait and see. The childish press release issued by Blue Origin yesterday, claiming its manned lunar lander was far better than SpaceX’s Starship and should have been chosen by NASA, suggests that the course change has not been as thorough as one would hope. The amount of intellectual dishonesty contained in that release is somewhat disturbing, especially coming from a rocket company:

Blue Origin appears to be, at minimum, cherry picking its comparisons. The graphic notes that the Starship-Super Heavy system hasn’t launched yet. Starship has launched six miles into the air on several occasions, but not with its Super Heavy booster. It also points out that SpaceX’s Starship facilities in Boca Chica, Texas have never accommodated an orbital launch. Blue Origin, though has never launched any rocket to orbit from anywhere.

The graphic doesn’t, however, note the cost of the Starship lunar lander. SpaceX’s proposal estimates that it will cost NASA $2.9 billion, while Blue Origin’s gave a price of $5.9 billion. [emphasis mine]

For the management of a rocket company to not recognize the fundamental facts indicated by the highlighted words above, or to make believe they are unimportant, does not bode well for that rocket company. Rather than focusing on getting its rocket finally off the ground, the management appears instead unwilling to face some hard facts, and fix them.

Meanwhile, SpaceX keeps barrelling along, focused not on petty managment issues or whiny complaints, but on actually building rockets that fly.

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Zhurong travels another 700 feet on Mars

Zhurong's location

According to a new update from China’s state-run press today, since the last update of its Zhurong Mars rover on July 31st, the rover has traveled just over 700 feet, for a total travel distance of about 2,624 feet, just under a half mile.

As of August 6, 2021, the rover has worked on the surface of Mars for 82 Martian days and the orbiter has been in orbit for 379 days. The two are in good condition and functioning properly.

The report provides no other real information.. I have indicated on the map to the right the range in which this travel distance could have taken Zhurong. Hopefully they will release more information soon.

The nominal mission was originally planned for 90 days. Right now it looks like the rover will easily exceed that.

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SpaceX stacks Starship on top of Superheavy

Superheavy with Starship on top
Click for original image.

Capitalism in space: Only three days after the company had rolled Superheavy prototype #4 to the launchpad, SpaceX today stacked Starship prototype #20 on top, uniting for the first time the entire rocket.

All told, the rocket is 395 feet high, about 32 feet taller than the Saturn-5.

The photo to the right, reduced slightly to post here, was posted by Elon Musk earlier today. It also makes obvious several things that will be different for this Starship flight compared to the previous suborbital hops. Starship’s dark exterior is because it is covered with thermal tiles designed to protect it as it returns to Earth flying through the atmosphere at orbital speeds.

Note also the grid fins on Superheavy. Apparently they will be open during the entire flight, instead of unfurling shortly after stage separation as is done with Falcon 9.

I am not sure what the vertical attachments near the bottom of Superheavy are for. The plan is for the stage to land in the Gulf of Mexico, so it does not need landing legs. Could these be attachment points for holding the rocket to the launchpad?

I have been predicting a late September/early October date for this rocket’s first orbital launch test. SpaceX is sure working hard to beat that timeline. They still need to do tank tests and static fire tests of the whole assembly, but based on past schedules, they might get this done in only a few weeks. If so, it means they might be able to launch before the end of August.

My god, if only other American rocket companies worked in this manner. Imagine what wonders they all could accomplish.

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Astra to attempt orbital launch later in August

Capitalism in space: The smallsat rocket company Astra has announced that it will attempt to complete its first successful orbital launch before the end of this month, launching a Space Force satellite.

The U.S. Space Force has booked two missions with Astra, the Bay Area company announced today (Aug. 5). The first flight will launch a test payload for the Department of Defense’s Space Test Program from the Pacific Spaceport Complex in Kodiak, Alaska, during a window that runs from Aug. 27 through Sept. 11.

Astra has two previous test launches that attempted to reach orbit and failed. The second barely missed, because of a fuel mixture issue that had it run out of fuel prematurely.

If successful, this will make Astra the third operational American smallsat rocket company, following Rocket Lab and Virgin Orbit. Four others have promised launches in 2021. By next year the competition in this smallsat launch industry should be quite fierce.

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Virgin Galactic reopens suborbital ticket sale, raises price, delays next flight

Capitalism in space: Virgin Galactic announced yesterday that it is resuming ticket sales for flights on its reusable SpaceShipTwo spacecraft, raising the price from the old price of $250,000 to a new price of $450,000.

Virgin Galactic is offering customers three options: purchase a single seat, buy several together or book an entire flight on the eight-passenger Unity (or other space planes that come into operation, such as the recently built VSS Imagine). The company also sells seats for microgravity research and professional astronaut training. Those are in a different tier, going for $600,000 apiece, Colglazier said during a call with investors on Thursday afternoon.

The announcement also revealed that they are delaying their next flight until September. That flight has been scheduled for the summer for months. The company is also delaying the start of regular commercial flights until late in ’22, in order to make some upgrades to their spacecraft.

By that time, regular orbital tourist flights will have become almost routine. Moreover, one has the option to experience weightlessness for far less buying a ticket on one of the various companies that fly “vomit comet” airplanes.

One wonders if the demand for these flights will be sustainable. We shall see.

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China launches military communications satellite

China’s Long March 3B rocket yesterday successfully launched a military communications satellite.

This was China’s eighth government launch since the beginning of July, in a span of only five weeks.

The launch was from an interior spaceport, so the rocket’s strap-on boosters and first stage core landed within China. No word if any landed near or on habitable areas, or if the Chinese were using parachutes or grid fins to control their landing.

The leaders in the 2021 launch race:

26 China
20 SpaceX
12 Russia
3 Northrop Grumman
3 Rocket Lab

The U.S. still leads China 30 to 26 in the national rankings.

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