Tag: science

Hubble data detects persistent water vapor on one of Europa’s hemispheres

1:30 pm

Using data from the Hubble Space Telescope spanning sixteen Earth years, scientists have detected the presence of water vapor on Europa, but strangely spread only across one of the moon’s hemispheres.

Previous observations of water vapor on Europa have been associated with plumes erupting through the ice, as photographed by Hubble in 2013. They are analogous to geysers on Earth, but extend more than 60 miles high. They produce transient blobs of water vapor in the moon’s atmosphere, which is only one-billionth the surface pressure of Earth’s atmosphere.

The new results, however, show similar amounts of water vapor spread over a larger area of Europa in Hubble observations spanning from 1999 to 2015. This suggests a long-term presence of a water vapor atmosphere only in Europa’s trailing hemisphere – that portion of the moon that is always opposite its direction of motion along its orbit. The cause of this asymmetry between the leading and trailing hemisphere is not fully understood.

First, it must be emphasized that the amounts of atmospheric water being discussed are tiny, so tiny that on Earth we might consider this a vacuum.

Second, that the water vapor is only seen on the trailing hemisphere suggests there is some sort of orbital influence involved, though what that influence is remains unknown.

Hopefully when Europa Clipper finally arrives in orbit around Jupiter in 2030, with a path that will fly past Europa fifty times, we will some clarity on these questions.

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A gecko on Mars

12:24 pm

Gecko on Mars
Click for full image.

Today’s cool image is also today’s picture of the day from the science team of the high resolution camera on Mars Reconnaissance Orbiter (MRO. That picture, rotated, cropped, and reduced to post here, can be seen to the right. As the caption authors Sharon Wilson and Sarah Sutton write:

The smooth volcanic surfaces in the Gordii Fossae region are sometimes interrupted by long, narrow troughs, or fissures. These fissures form when underground faults, possibly involving magma movement, reach the near-surface, allowing material to collapse into pits or an elongated trough. This fissure appears to have erupted material that flowed onto the surface.

If you use your imagination, this trough resembles a gecko with its long tail and web-shaped feet!

This impression is even more evident in the wider image taken by MRO’s context camera below.
» Read more

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Webb telescope finally arrives at launch site in French Guiana

2:54 pm

Webb deployment

After almost twenty years of construction (a decade behind schedule) and a cost of $10 billion, ($9.5 billion over budget), the James Webb Space Telescope today arrived at the processing facility at Arianespace’s French Guiana spaceport, where it will be prepared for a December 18, 2021 launch on an Ariane 5 rocket.

Once launched the telescope, which is not a replacement for Hubble because it observes in the infrared (not optical) and is optimized for deep space cosmology, will take two weeks to reach its orbital position about a million miles from Earth, as shown in the graphic.

Let us all cross our fingers and toes that it all works as designed, for if it doesn’t this will be the biggest failure ever in the history of NASA.

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Today’s blacklisted American: Brownstone Institute blackballed by LinkedIn for associating with famed Harvard epidemiologist

11:12 am

They’re coming for you next: The non-profit Brownstone Institute, founded in 2021 to provide an outlet for educated dissent on science and economic issues, has found itself repeatedly censored by LinkedIn in the past two weeks because one of its founders is famed Harvard epidemiologist Martin Kulldorff.

Brownstone Institute: Censored

If you are a regular reader of this column you might remember Kulldorff’s name. He was blacklisted by the CDC, Twitter, and LinkedIn in late August because he dissents from the oppressive lockdown policies those organizations advocate. He was also one of the leading authors of the Great Barrington Declaration [also available here a pdf], which strongly opposes the policies of lockdowns, mandates, and the other totalitarian actions taken by governments since 2020, and instead calls for the more traditional (and successful) “focused” approach for dealing with epidemics and diseases: Protect the vulnerable (the old and sick) from the disease while letting everyone else (the young and healthy) live normal lives and thus get infected quickly, become immune, and thus squelch off the virus.

Kulldorff is also one of the world’s preeminent experts on vaccine safety and “helped develop the CDC’s current system for monitoring potential vaccine risks.”

Anyway, it appears that on October 1st, LinkedIn suddenly discovered that Kulldorff was one of the senior scholars at the Brownstone Institute, and began deleting the institute’s posts.
» Read more

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Dusty chaos in Martian canyons

1:37 pm

Outcrops in dusty chaos on Mars
Click for full image.

Cool image time! The photo to the right, cropped and reduced to post here, was taken on May 30, 2021 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows the dusty dry floor of the chaos region of rough terrain in a side canyon of Valles Marineris, near its outlet. The color strip and the bright outcrops suggest that this terrain contains interesting minerals and resources. To determine exactly what those materials are however requires more information not available in this photo.

This ancient chaos terrain is the leftover eroded sea floor of a intermittent inland sea, leftover water from the catastrophic floods that are theorized to have flowed out of Valles Marineris and carved its gigantic canyons.

The overview map below shows this hypothesized sea.
» Read more

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Ancient fossil river in the very dry equatorial regions of Mars

1:27 pm

Inverted Channel on Mars
Click for full image.

Cool image time! The photo to the right, rotated, cropped, and reduced to post here, was taken on August 29, 2021 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows what the scientists label an “inverted channel in Arabia Terra,” a small example of the more than 10,000 miles of fossilized rivers in this region on Mars that scientists have identified using MRO.

They are made of sand and gravel deposited by a river and when the river becomes dry, the channels are left upstanding as the surrounding material erodes. On Earth, inverted channels often occur in dry, desert environments like Oman, Egypt, or Utah, where erosion rates are low – in most other environments, the channels are worn away before they can become inverted. “The networks of inverted channels in Arabia Terra are about 30m high and up to 1–2km wide, so we think they are probably the remains of giant rivers that flowed billions of years ago. [emphasis mine]

Since this fossilized river is located at 11 degrees north latitude, smack in the middle of the dry equatorial regions of Mars, it has certainly been a dry desert for a very long time. You can see how barren the terrain appears by looking at the wider view afforded by MRO’s context camera below.
» Read more

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As expected, Pluto’s atmosphere is freezing as its orbit takes it from the Sun

10:48 am

Data from ground-based telescopes has now confirmed that Pluto’s nitrogen atmosphere has begun it annual winter freeze out as the planet’s somewhat elliptical 248-year-long orbit takes it away from the Sun.

For about 25 years, Pluto has been moving farther and farther away from the sun, so its surface temperature has been going down. And with these recent observations, the researchers found evidence showing that Pluto’s atmosphere is actually refreezing back onto its surface as the dwarf planet gets colder and colder. Pluto is so far from the sun that, as time goes on, it will get distinctly farther away (and colder) before getting closer to the sun in other regions of its immense orbit.

The astronomers were able to detect this refreezing by observing the planet as it eclipsed a star in 2018.

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Data from Perseverance confirms Jezero Crater once held a lake

6:52 am

figure 5 from paper showing ancient lake in Jezero Crater

According to a newly published paper, the data obtained by the rover Perseverance has confirmed and refined what orbital data has suggested, that Jezero Crater once held a lake. From the abstract:

We analyze images taken by the rover in the three months after landing. The fan has outcrop faces that were invisible from orbit, which record the hydrological evolution of Jezero crater. We interpret the presence of inclined strata in these outcrops as evidence of deltas that advanced into a lake. In contrast, the uppermost fan strata are composed of boulder conglomerates, which imply deposition by episodic high-energy floods. This sedimentary succession indicates a transition, from a sustained hydrologic activity in a persistent lake environment, to highly energetic short-duration fluvial flows.

In other words, the crater first held a lake, which as it slowly dried out was periodically renewed by flash floods. The distinct delta of material that made Jezero Crater the prime landing site was apparently formed during the period when the lake existed. The conditions that caused the subsequent flash floods is as yet not been determined, though it likely is related to the red planet’s long term evolution.

The image above, figure 5 from the paper, shows the inferred lake in that early history. The red cross marks Perseverance’s landing site.

This data reinforces the fundamental scientific mystery of Mars. It shows evidence that liquid water once flowed on the surface of Mars, even though other long term data of the planet’s history says the Martian atmosphere has been too thin and too cold to allow that to happen. There is evidence that the atmosphere might have once been thicker, but no computer model or theory has been able to produce a time when it was warm enough.

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Chang’e-5 lunar samples youngest ever found

6:28 am

The uncertainty of science: The lunar samples returned to Earth by China’s Chang’e-5 lander have been found to be the youngest ever found, about two billion years old and a billion years younger than any other previous sample, with a composition that confirms the material in this area was also the youngest volcanism so far found on the Moon.

Collecting young lunar rocks was one of the main objectives for the Chang’e-5 mission, which sent a lander to the Moon in December 2020. The craft grabbed 1.7 kilogram (4 pounds) of lunar regolith from the vast volcanic plain of Oceanus Procellarum and flew back to Earth within the month. Observations from lunar orbit had identified this mare to be younger than other areas by its paucity of craters, which suggested that the lava there had flowed more recently. By dating the samples returned to Earth, the scientists confirm that volcanism occurred later in Oceanus Procellarum than other areas of the Moon.

Many news stories are claiming that the young age of these samples is a surprise, but this isn’t true. It was expected, as the quote above indicates.

However, the composition of the rocks did not match what was expected. Though created by volcanism, it appears the material did not have kind of composition seen in other lunar volcanic rocks. This is now a new puzzle for scientists.

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Today’s blacklisted American: Woman denied kidney transplant in Colorado because she is unvaccinated

1:10 pm

The unvaccinated denied healthcare in Colorado
No healthcare in Colorado permitted for the unvaccinated. Let them die!

Persecution is now cool! A woman who has stage 5 renal failure was suddenly told by UCHealth (University of Colorado Health) — just before her kidney transplant operation — that she was banned from the hospital because both she and her donor are unvaccinated.

“Here I am, willing to be a direct donor to her. It does not affect any other patient on the transplant list,” Jaimee Fougner, Leilani Lutali’s kidney donor, told CBS4. “How can I sit here and allow them to murder my friend when I’ve got a perfectly good kidney and can save her life?”

Lutali said she received a letter from Colorado health system UCHealth at the end of September explaining that she and Fougner have 30 days to begin the vaccine process. They would be removed from the kidney transplant list if they refuse the shots. “I said I’ll sign a medical waiver. I have to sign a waiver anyway for the transplant itself, releasing them from anything that could possibly go wrong,” said Lutali. “It’s surgery, it’s invasive. I sign a waiver for my life. I’m not sure why I can’t sign a waiver for the COVID shot.”

According the article, when they first scheduled the surgery in August they were told by the hospital that being unvaccinated was not a problem. This changed suddenly in late September, at the last moment.
» Read more

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The wavy and beautiful edge of the northern ice cap of Mars

12:32 pm

The scarp of the north pole icecap on Mars
Click for full image.

Cool image time! The photo to the right, cropped and reduced to post here, was taken on August 7, 2021 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows the many layered scarp that forms the edge of the northern polar ice cap on Mars, probably more than 2,000 feet high.

Those layers are significant, as they indicate the many climate cycles that scientists think Mars has undergone over the eons as the red planet’s rotational tilt, or obliquity, rocked back and forth from 11 degrees inclination to as much as 60 degrees. At the extremes, the ice cap was either growing or shrinking, while today (at 25 degrees inclination) it appears to be in a steady state.

Why the layers alternate light and dark is not known. The shift from lighter colors at the top half and the dark bottom half marks the separation between the top water ice cap and what scientists label the basal unit. It also marks some major change in Mars’ climate and geology that occurred about 4.5 million years ago.
» Read more

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