Tag: science

A Mars mesa carved by floods and lava?

1:29 pm

Overview map of Kasei Valles

With today’s cool image we once again start our journey from afar, and zoom in. The overview map to the right focuses in on the thousand-mile-long Kasei Valley on Mars.

The blue area is where scientists postulate a lake once existed, held there by an ice dam (indicated by the white line). At some point that ice dam burst, releasing the water in a catastrophic flood that created the braided flow features that continue down Kasei Valles to the northern lowland plain of Chryse Planitia.

The black area marks a giant lava flow that scientists believe came later, following the already carved stream channels for a distance of 1,000 miles, traveling at speeds of 10 to 45 miles per hour.

The red dot near the Kasei Valles resurgence is today’s cool image.
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Government shutdown threatens Lucy asteroid mission

9:00 am

Government marches on! The possibility that the federal government could shut down because of the inability of Congress and the Biden administration to pass a funding bill or raise the debt limit now threatens the launch of the Lucy mission to the asteroid belt.

If no budget agreement is reached the government will shut down on October 1st. If the debt limit isn’t raised that shutdown could follow soon thereafter, even if a budget is passed.

The launch window for the mission is from October 16 to November 7, 2021. If the spacecraft does not launch in that window the science team says it will likely require a major rethinking of the entire project, as it will be difficult to find another opportunity to visit the same set of asteroids.

Right now the chances of a shutdown are very high, as the Democrats are pushing big spending bills without any negotiations with the Republicans. In answer, the Republican caucus has said that none of its members will support raising the debt limit. Without the latter any passed spending bill will soon be moot, as the debt limit will soon be reached, blocking further government spending.

Though I personally would be very saddened if Lucy was prevented from launching, that loss would be well compensated for by having the federal government out of business. The evil and corruption promoted by it far outweighs the good work done by several minor space missions.

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Perseverance as seen from orbit

12:00 pm

Perseverance as seen from orbit
Click for full image.

Overview map
Click for interactive map.

The science team for the high resolution camera on Mars Reconnaissance Orbiter (MRO) have snapped a picture of Perseverance at its present location in Jezero Crater.

The first image to the right, cropped to post here, shows the rover as a white dot to the right of the two long sand dunes. If you look close image, you can see the rover’s tracks near the bottom of the image.

Ingenuity is likely also in the full image, but is likely too small for MRO’s high resolution camera to pick out.

The second image is a overview map. The green dot marks the rover’s position, with the red dot Ingenuity’s present position. The dotted white line shows the route the rover has taken so far. The light brown line indicates the flight paths for all of Ingenuity’s flights. The yellow dotted line indicates the future planned route of Perseverance.

With Mars about to slip behind the Sun, communications with both rovers, Perseverance and Curiosity, as well as all the orbiters, will shortly go silent for about two weeks.

When that pause ends, the question will be where Perseverance goes next. The original plan was to retreat back along its previous path, going to the southeast before heading north past the landing site. I strongly suspect that they will instead head directly to the landing site, going to the northeast across the rough terrain, both to see something new as well as further test the rover’s ability to travel tougher ground.

They avoided that area initially because they were still in the rover’s check out period. Now that they know it works, there is no reason to avoid that ground, especially because it will be ground they have not viewed before. They could even use Ingenuity to scout it out more thoroughly.

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BepiColombo about to make first of six Mercury flybys

11:16 am

The European/Japanese BepiColombo probe will make its first of six fly-bys of Mercury on October 1, 2021, as it steadily adjusts its flight path to enter orbit around the planet in 2025.

The mission is made up of two Mercury orbiters, Europe’s Mercury Planetary Orbiter and Japan’s Mio orbiter.

During the flybys it is not possible to take high-resolution imagery with the main science camera because it is shielded by the transfer module while the spacecraft is in cruise configuration. However, two of BepiColombo’s three monitoring cameras (MCAMs) will be taking photos from about five minutes after the time of close approach and up to four hours later. Because BepiColombo is arriving on the planet’s nightside, conditions are not ideal to take images directly at the closest approach, thus the closest image will be captured from a distance of about 1000 km.

The first image to be downlinked will be from about 30 minutes after closest approach, and is expected to be available for public release at around 08:00 CEST on Saturday morning. The close approach and subsequent images will be downlinked one by one during Saturday morning.

The cameras provide black-and-white snapshots in 1024 x 1024 pixel resolution, and are positioned on the Mercury Transfer Module such that they also capture the spacecraft’s solar arrays and antennas. As the spacecraft changes its orientation during the flyby, Mercury will be seen passing behind the spacecraft structural elements.

These will be the first close-up pictures of Mercury since the Messenger orbiter mission ended in 2015.

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Data suggests the winds in Jupiter’s Great Red Spot are changing

2:46 pm

Changing wind speeds in Great Red Spot
Click for original image.

Data accumulated from 2009 to 2020 by the Hubble Space Telescope suggest that the outer winds in Jupiter’s Great Red Spot have speeded up by about 8%, while the winds in the spot’s inner regions have slowed.

The change in wind speeds they have measured with Hubble amount to less than 1.6 miles per hour per Earth year. “We’re talking about such a small change that if you didn’t have eleven years of Hubble data, we wouldn’t know it happened,” said Simon. “With Hubble we have the precision we need to spot a trend.” Hubble’s ongoing monitoring allows researchers to revisit and analyze its data very precisely as they keep adding to it. The smallest features Hubble can reveal in the storm are a mere 105 miles across, about twice the length of the state of Rhode Island.

“We find that the average wind speed in the Great Red Spot has been slightly increasing over the past decade,” Wong added. “We have one example where our analysis of the two-dimensional wind map found abrupt changes in 2017 when there was a major convective storm nearby.”

The graphic above shows the different wind speeds between the spot’s inner and outer regions, not the increase in speed described in this press release.

To put it mildly, these results are uncertain. We simply could be seeing the long term random fluctuations in the storm, or the change could simply be a reflection of the data’s margin of error. Moreover, since the data covers only the top layer of the Great Red Spot, it tells us nothing about the storm’s deeper regions or its more fundamental origins.

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Rivulets in Martian lava

2:14 pm

Overview map

Today’s cool image is another example of scientists finding cool things hidden within distant pictures. The small white rectangle on the overview map to the right shows us where we are heading, to the severely eroded lava plains to the southwest of Mars’ largest volcano, Olympus Mons.

The white spot is about 500 miles from the caldera of Olympus Mons. In elevation it sits about 58,000 feet below that caldera, more than twice the height of Mt. Everest. Yet, despite these great distances, the material at that white rectangle was almost certainly laid down during an eruption from Olympus Mons, thus illustrating the gigantic scale of volcanic events on Mars. Because of the red planet’s light gravity, about 38% of Earth’s, not only can lava flow farther, it does so much faster.

The second image below is a wide angle photo taken by the context camera on Mars Reconnaissance Orbiter (MRO) in January, 2012, rotated, cropped, expanded, and enhanced to post here.
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Glaciers in the Martian south latitudes

1:12 pm

Glaciers in Mars' southern hemisphere
Click for full image.

Most of the glacier cool images I have posted in the past few years from the high resolution camera on Mars Reconnaissance Orbiter (MRO) have shown the obvious glacial features found in the northern hemisphere in that 2,000 mile long strip of chaos terrain at about 40 degrees latitude I dub “Glacier Country.”

Today’s glacier image to the right, cropped and reduced to post here, takes us instead to the southern hemisphere, into Hellas Basin, the death valley of Mars. The picture was taken on April 8, 2021, and in the full picture gives us a myriad of examples of glacial features. The section featured to the right focuses in on what appears to be an ice covered south facing slope, which in the southern hemisphere will get the least sunlight.

Think of the last bits of snow that refuse to melt after a big blizzard. They are always found in shadowed areas, which in the southern hemisphere would be this south-facing slope.

The overview map below shows how this location, marked by the small white rectangle, is inside Hellas Basin, at a low altitude comparable to the northern lowland plains. The feature is also a comparable latitude, 43 degrees south, to the glacier country of the north.
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InSight detects the three more large quakes on Mars, the most powerful measured so far

8:40 am

In the past month InSight’s seismometer has detected the three most powerful earthquakes so far measured on Mars, with one located in a region where no quakes had as yet been seen.

InSight spotted 4.2- and 4.1-magnitude temblors on Aug. 25, then picked up another roughly 4.2-magnitude quake on Sept. 18 that lasted for nearly 90 minutes, NASA officials announced on Wednesday (Sept. 22).

The previous record holder, which InSight measured in 2019, clocked in at magnitude 3.7 — about five times less powerful than a 4.2-magnitude quake.

At this time scientists have only been able to roughly pinpoint the location of the two August quakes, with the 4.1 quake occurring about 575 miles away, putting it in the volcanic plains where InSight sits and closer than the location of most of the previous large quakes near the long surface fissures dubbed Cerberus Fossae 1,000 miles away.

The August 4.2 quake’s is even more interesting, as its location is the farthest away of any so far detected, at an estimated distance of 5,280 miles away. The scientists presently suspect but have not yet confirmed that it may be located in the western end of Valles Marineris, Mars’ largest canyon.

The lander itself continues to fight a loss of power due to the amount of dust on its solar panels, forcing the science team to shut down practically all its other instruments so that the seismometer could continue operating.

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A clue to the Martian history of volcanic eruptions

1:00 pm

Dark layers in Medusae Fossae Formation
Click for full image.

Anyone who has taken even a single glance at a map of Mars cannot help but recognize that the red planet was once engulfed with repeated gigantic volcanic eruptions able to build numerous volcanoes larger than anything seen anywhere else in the solar system.

The cool image to the right, rotated, cropped, and enlarged to post here, provides a clue into those past eruptions, now thought to have been active for more than several billion years, with the most recent large activity ending several tens of millions of years ago. The photo was taken on May 7, 2021 by the high resolution camera on Mars Reconnaissance Orbiter (MRO), and shows just one tiny portion of the vast Medusae Fossae Formation, the largest thick volcanic ash deposit on Mars, about the size of India and what scientists think is the source of most of the planet’s dust.

What makes this picture interesting are the dark layers in the lower hollows. They indicate that this deposit was placed down in multiple eruptions, some of which produced material that appears dark blue in MRO images, and suggest that eruption was different than previous and subsequent eruptions.

The white cross on the overview map below notes the location of this picture in the Medusae Fossae Formation.
» Read more

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Martian mountaintop

11:03 am

Mountains on Mars
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The outcrop top
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Cool image time! The photo to the right, cropped, reduced, and enhanced to post here, was taken on September 21, 2021 by Curiosity’s high resolution mast camera, and shows the top of that spectacular rock outcrop about 200 feet to the west of where the rover presently sits. The top image, from my September 16, 2021 post, “Curiosity: Into the Mountains!”, indicates the location of the photo with the black rectangle. The red dotted line indicates the rover’s future planned route.

I estimate the whole outcrop is about 100 feet high, which means the cliff section seen in the photo to the right is probably about 30 feet high. It would make a great challenge for any number of rock climbers I know.

What makes this image especially striking are the overhanging rocks at the peak’s top. In the Martian gravity, about one third that of Earth’s, it is possible for much more delicate rock shapes to remain structurally stable, and the sharp jagged boulders hanging out at the top of this cliff demonstrate that in a quite breath-taking way. On Earth such delicate rocks would likely have quickly fallen.

The Curiosity science team is obviously most interested in the massive layers revealed by this cliff. I am also sure they are also as enthralled by the scenery as I am.

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Galaxies in the early universe don’t fit the theories

9:33 am

The uncertainty of science: New data from both the ALMA telescope in Chile and the Hubble Space Telescope about six massive galaxies in the early universe suggest that there are problems and gaps in the presently accepted theories about the universe’s formation.

Early massive galaxies—those that formed in the three billion years following the Big Bang should have contained large amounts of cold hydrogen gas, the fuel required to make stars. But scientists observing the early Universe with the Atacama Large Millimeter/submillimeter Array (ALMA) and the Hubble Space Telescope have spotted something strange: half a dozen early massive galaxies that ran out of fuel. The results of the research are published today in Nature.

Known as “quenched” galaxies—or galaxies that have shut down star formation—the six galaxies selected for observation from the REsolving QUIEscent Magnified galaxies at high redshift. or the REQUIEM survey, are inconsistent with what astronomers expect of the early Universe.

It was expected that the early universe would have lots of that cold hydrogen for making stars. For some galaxies to lack that gas is inexplicable, and raises questions about the assumptions inherent in the theory of the Big Bang. It doesn’t disprove it, it simply makes it harder to fit the facts to the theory, suggesting — as is always the case — that the reality is far more complicated than the theories of scientists.

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How to discover interesting things on Mars

2:13 pm

Overview map

Today’s cool image will do something a little different. We are going to begin in orbit, and by step-by-step zooming in we will hopefully illustrate the great challenge of finding cool geological features on the surface of Mars.

The first image to the right is an overview map of the Valles Marineris region. To its east, centered at the white dot, is a vast region of chaos terrain, endless small buttes and mesas and criss-crossing canyons. Travel in this region will always be difficult, and will likely always require some form of helicopter to get from point to point.

What is hidden in that terrain? Well, to find out you need to take a global survey from orbit with a good enough resolution to reveal some details. Below is a mosaic made from two wide angle context camera pictures taken by Mars Reconnaissance Orbiter (MRO).

Context mosaic of chaos terrain
For full images go here and here.

This mosaic, rotated, cropped, and reduced to post here, only captures a small section of the long north-south strips taken by MRO. The orbiter has taken tens of thousands of these strips, in its effort to produce a global map of Mars that shows some reasonable detail.

Do you see anything in this mosaic that looks interesting? Scientists need to pore over such images, one by one, searching for geology that is both puzzling and revealing. Sometimes the features are obvious, such as a single blobby crater in the flat relatively featureless northern lowlands.

Sometimes however the search can be slow and time-consuming because the terrain is complex, as is the example to the right. The many mesas and canyons can hide many interesting features. Since MRO can’t possibly take high resolution photos of everything, scientists have to pick and choose.

The planetary scientists who use MRO did find something here worth looking at in high resolution. Can you find it? Normally I’d provide a box to indicate it, but this time I’d thought I’d challenge my readers. Before you click below to see the feature, see if you can find it yourself in this mosaic. What would you want to photograph in high resolution?
» Read more

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Landing site chosen for VIPER lunar rover

9:49 am

Overview map

NASA has now chosen the landing site for its VIPER rover, in a relatively flat area about 85 miles from the Moon’s south pole and near the western edge of Nobile Crater (pronounced No-BEEL-e).

The white rectangle on the overview map to the right shows the landing zone. The green cross on the rim of Shackleton Crater marks the South Pole. The red outlines inside craters are regions that are believed to be permanently shadowed, and thus locations that might have water ice within them. Additionally, the data suggests there are a handful of small areas inside craters within the landing zone that might also have ice.

From the press release:

The area VIPER will study in the Nobile region covers an approximate surface area of 36 square miles (93 square kilometers), 10 to 15 miles (16 to 24 km) of which VIPER is expected to traverse through during the course of its mission. During this time, the rover will visit carefully chosen areas of scientific interest that will provide further insight into a wide array of different kinds of lunar environments. The VIPER team will look to characterize ice and other resources in these areas using VIPER’s sensors and drill.

The mission’s planned lifespan is presently set at 100 days. While the Moon’s day/night is 28 days long, the rover will likely see little darkness, since at this very high latitude the Sun will simply circle the sky near the horizon.

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Glacial falls on Mars

11:01 am

A glacial falls on Mars
Click for full image.

Cool image time! The photo to the right, cropped and reduced to post here, was taken on July 2, 2021 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It provides us just one more clear example of the many glaciers found in that 2,000-mile-long strip of chaos terrain at 30 to 47 degrees north latitude that runs between the northern lowland plains and the southern cratered highlands, a region I like to call Mars’ glacier country.

What makes this glacial feature interesting is that these ice-filled alcoves are south-facing, which in the northern hemisphere means they get the most sunlight. Yet, the ice here remains, well-protected by its layer of dust and debris. Think of the dirty ice slush that manages to survive the longest on city streets in the spring. The dirt acts as protection so that the ice takes more time to melt.

The overview map as always provides our context.
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SpaceX targeting 6 commercial manned flights per year

9:06 am

Capitalism in space: With the successfully completion of its first manned orbital private space, SpaceX officials announced yesterday that they are expecting to fly about six such commercial manned flights per year.

Benji Reed, SpaceX’s senior director for its human spaceflight program projected as many as a half a dozen flights a year. “There’s nothing really that limits our capability to launch,” he said. “It’s about having rockets and Dragons ready to go and having everything in the manifest align with our other launches.”

…“The reality is the Dragon manifest is getting busier by the moment,” Reed said, noting the planned flight in early 2022 of four passengers for customer Axiom Space that will actually fly to and stay on the ISS for a few days. “It just goes on from there. We have a number of NASA missions that we’ll do, and we also have a growing backlog of commercial astronaut missions that we’re looking forward to perform.” [emphasis mine]

The highlighted words are most intriguing, suggesting that SpaceX might have an already signed line-up of customers ready to pay the ticket price to fly on a Dragon capsule.

Meanwhile, Elon Musk announced late yesterday that he has decided to donate $50 million of his own money to St. Jude Children’s Research Hospital, in celebration of the completion of the Inspiration4 flight.

“This brings tears to my eyes,” wrote Inspiration4 medical officer Hayley Arceneaux, a St. Jude physicians assistant and survivor of childhood bone cancer, of Musk’s donation. “Thank you Elon Musk for this generous donation toward our $200 million dollar fundraising goal for St. Jude!!!”

Isaacman also thanked Musk and reminded the public that the fundraiser is still underway. Isaacman donated $100 million of his own money to the fundraising goal, then donated the three other seats on Inspiration4 to raise awareness for St. Jude. Arceneaux was selected by St. Jude to fill the “Hope” seat on the crew.

If you wish to make your own donation to St. Jude, you can do so here. You can donate cash directly, or you can bid to win one or more of a variety of items that were carried on the flight.

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Badlands on the floor of a Martian crater

1:27 pm

Badlands on the floor of a Martian crater
Click for full image.

Cool image time! The photo to the right, rotated, cropped, and reduced to post here, shows one small section of a 30-mile-wide unnamed crater in the cratered equatorial regions of Mars northeast of Hellas Basin. Taken on July 21, 2021 by the high resolution camera on Mars Reconnaissance Orbiter (MRO), the science team labeled merely as “Rocky crater fill.”

Being at 17 degrees south latitude, there shouldn’t be any ice features in this crater, and the high resolution image to the right seems to confirm this. All we see is an endless plain made up of innumerable small sharp rock ridges interspersed with small low areas filled with sand dunes. This is bed rock, and if its strange stucco-like appearance was caused by a past glacial era, that era is long gone.

Below is a mosaic showing the entire crater, created from two MRO context camera images.
» Read more

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Curiosity: Into the mountains!

12:46 pm

Curiosity's path into the mountains
Click for full image.

Overview map
Click for interactive map.

Time for another cool image from Curiosity. The photo above was taken by one of the rover’s navigation cameras today, and looks south in the direction of Curiosity’s future travels. The red dotted line shows that planned route, along the cliff face to then turn west into what the science team has dubbed Maria Gordon Notch, in honor of a Scottish scientist from the early 20th century.

The map to the right gives the context as seen from above, as well as the planned travels beyond the notch. The white dotted route marks Curiosity’s actual travel route. The red dotted line marks the planned route. The yellow lines the area seen in the above picture.

At present Curiosity is paused as it performs a new drilling campaign about 200 feet from the base of that cliff face, drilling the rover’s 33rd hole on Mars.

The outcrop resembling a ship’s prow on the image’s right, which I still consider the most spectacular rock outcrop seen yet on any planetary mission anywhere, is about 100 feet high.

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Lozenge-shaped hole in Martian crater

12:15 pm

Hole in crater floor
Click for full image.

Cool image time! The photo to the right, rotated, cropped, reduced, and enhanced to post here, was taken on June 7, 2021 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

The left image shows what the scientists have dubbed a “lozenge-shaped depression” in the middle of an unnamed 60-mile-wide crater in the southern cratered highlands of Mars. The right image shows the same exact depression, but I have brightened the photo in order to see the details in the shadowed depression.

Though the image is inconclusive, the bottom of the darkest spot in that depression cannot be seen, suggesting it could be an entrance into a larger void below.

Even if there is no voids below, why is this depression here? What caused it? The wider view of MRO’s context camera below might give us a hint.
» Read more

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The layered history of Mars as revealed in Valles Marineris

1:01 pm

Layered cliff in Valles Marineris
Click for full image.

Cool image time! The photo to the right, rotated, cropped, and reduced, shows just one tiny cliff face in the gigantic canyon on Mars dubbed Valles Marineris. The photo was taken on June 13, 2021 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

Like many other similar cliff faces that MRO has photographed and that I have previously highlighted, there are many many layers visible here. In fact, it appears that almost every cliff in this part of Valles Marineris is many layered, suggesting that like the Grand Canyon on Earth, the canyon as it was carved exposed in great detail the long geological history of Mars.

In this part of Mars, each layer probably represents the placementof a new layer of volcanic material, pouring out from the giant volcanoes in the Tharsis Bulge to the west. In addition, overlain on this volcanic record are probably deposits lain down by the atmosphere as Mars underwent its many climate cycles due to the regular shifts in its orbit and rotational tilt.
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Make concrete on Mars using human blood?

9:17 am

What could possibly go wrong? Scientists at the University of Manchester in the United Kingdom have developed a new formulation that can use material known to exist on Mars, combined with the addition of astronaut blood, to produce useful concrete.

Working with simulated lunar and Martian soils, the team experimented with using human blood and waste products as binding material, and turned up some interesting results.

The work showed that a common protein in the blood called serum albumin could be used as a binder to produce a concrete-like material with compressive strength comparable to ordinary concrete. In investigating the mechanisms at play, the team found the blood proteins “curdle” to form “beta sheets” that extend outward to hold the material together.

Even more interestingly, the team found that urea, a waste product found in urine, sweat and tears, could be incorporated to increase this compressive strength by more than 300 percent. That is to say, the key to cosmic concrete stronger than what we have here on Earth might be found in our blood, sweat and tears (and urine).

This work was inspired by ancient building techniques, which often used pig blood in concrete for similar reasons.

Though a lot of this makes sense, especially the utilization of waste products like urine, the idea that future colonies will tap the blood of their citizens for construction purposes raises so many moral questions I can’t list them all here.

For example, let me throw out one possibility should no one think about this too much on Mars. Why not use this need for blood as a method of criminal punishment? Do something the ruling powers think is wrong and we will suck your blood from you to build the colony!

The moral consequences of our actions require long careful thought. Unfortunately, long careful thought simply no longer exists among today’s intellectual and political classes. Instead, they make almost all their decisions off the cuff, based on what “feels” right to them. You merely have to watch the many interviews of Dr. Anthony Fauci in the past year to see what I mean. Nothing he says about masks or mandates is really based on new research or data. He merely throws out an opinion that feels right, at the moment. Thus, he contradicts himself repeatedly, and most of his advice has been worse than useless, resulting in so many unexpected negative consequences they almost cannot be counted.

Try to imagine the horrors that could take place in a colony on Mars, where resources are in short supply, should construction require the use of human blood and the leadership there approaches its problems with the same cavalier attitude toward moral consequences? I can, and it chills my own blood to the core (no pun intended).

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An example why scientists think there were catastrophic floods on Mars

1:30 pm

Broken mesas on Mars
Click for full image.

Today’s cool image provides a nice illustration why scientists have long assumed that in the distance past there had been catastrophic floods of liquid water on Mars. The photo to the right, rotated, cropped, and reduced to post here, was taken on July 6, 2021 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows an east-west gully cutting between mesas to the north and south.

Because the highest mesas seem to be aligned, this suggests they were once part of the same formation, and something came along to carve that gap and gully between them.

What made the break? The overview map below as usual provides some context, which also provides a possible explanation.
» Read more

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Data from Opportunity suggests surface dew periodically appears even in the dry equatorial regions

4:43 pm

Using data from the rover Opportunity, scientists now think that the renewal of Martian salt crusts on rock surfaces on the rim of Endeavour Crater could possibly by caused by the appearance of rare thin wetting events, and that such events could have even occurred very recently and be on-going..

The scientists looked at the rate of erosion and renewal of the salt crusts, and found them to be in a steady state. The erosion is slow, taking from 200,000 to 2,000,000 years to remove 1 to 2 millimeters. However, periodically a thin film of water or wetting occurs, not unlike dew on Earth, which quickly acts to renew the crust. As David Mittlefehldt of the Astromaterials Research Office at the Johnson Space Center and the lead author of the paper explained to me,

Taken together, the data leaves open the possibility the salt mobilization has occurred within the last few thousand years. It could be ongoing in the sense that over a period of thousands? or hundreds? of years it might happen again.

In other words, the evidence suggests that every few hundred or thousand years the surface of these rocks gets wet, which results in the placement of a new thin layer of salt crusts.

Mittlefehldt also emphasized to me that these wetting events are rare, and “there is also the case that such an event may never come again because of changing conditions.”

The situation is essentially like on Earth, where in some places hydrologists measure the size of floods by how rare they are. A 1,000 year flood is big, but it happens very rarely. At Endeavour Crater these wetting events are comparably rare, but they do not involve big floods, but a mere moistening of the ground.

The location of Endeavour Crater is about 2 degrees south latitude, so it sits in the dry equatorial regions where no surface or near surface ice has so far been found. However, the cyclic nature of Mars’ orbit and obliquity could have changed this in the past, and could change this again in the future. At this time we simply don’t have enough information to know.

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On the edge of Mars’ glacier country

1:25 pm

Color dry mesas on Mars
Click for full image.

Today’s cool image sits right on the southern edge of Mars’ northern glacier country, at 29 degrees north latitude. The picture to the right, cropped and reduced to post here, was taken of this location on June 4, 2021 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows what appears to be the exposed and scraped bedrock and mesas on the floor of an unnamed 60-mile-wide crater.

That scraped bedrock is quite beautiful, reminiscent of the bare carved mesas and bedrock one sees throughout the southwest of the United States. To hike from that central valley to the top of the bright mesa would be a fine experience, especially because of the suggested change in colors in the color strip.

The overview map below gives more context.
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Sunspot update: Activity declines in August to just above prediction

12:02 pm

On September 1st NOAA released its update of its monthly sunspot cycle graph, showing the Sun’s sunspot activity for the past month. That graph is below, annotated to show the previous solar cycle predictions and thus provide context.

In August sunspot activity dropped from July so that it was only slightly above the prediction of NOAA’s panel of solar scientists, as indicated by the red curve. The blank streak at the very end of July ended on August 2nd (a streak of seven days and the longest in years), but was followed during the month by an additional five blank days.

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Glaciers and mesas on Mars

2:19 pm

Overview map

Cool image time! Today we return to glacier country on Mars, that band of mensae mesas and glaciers that stretches more than 2,000 miles in the northern mid-latitudes, as shown on the overview map above.

No rovers or landers have yet visited this region, nor are any planned. To the west just beyond the map’s left edge is the planned landing site of Europe’s Franklin rover. To the east and south and just beyond the map’s right edge is where America’s Perseverance rover presently travels in Jezero Crater.

Our journey today begins from afar, and will steadily zoom into the area of the red cross and a most intriguing feature seen in a recent picture taken by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

Before we look at that high resolution image, it is better to view the area using MRO’s context camera, as what it shows helps make sense of the features in the close-up.
» Read more

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NASA now targets December 18, 2021 for launch of Webb

1:12 pm

NASA today announced that it and the European Space Agency have scheduled the Ariane 5 launch of the James Webb Space Telescope from French Guiana for December 18, 2021.

The agency set the new target launch date in coordination with Arianespace after Webb recently and successfully completed its rigorous testing regimen – a major turning point for the mission. The new date also follows Arianespace successfully launching an Ariane 5 rocket in late July and scheduling a launch that will precede Webb. The July launch was the first for an Ariane 5 since August 2020.

Launching before the end of ’21 will allow NASA to claim that Webb is only be ten years behind schedule, not eleven. The cost overruns however remain astronomical (no pun intended). Initially budgeted at $500 million, Webb is now estimated to have cost $10 billion.

Once launched the telescope will take about six months to slowly move to its Lagrange point location about a million miles from the Earth, in the Earth’s shadow. During that time it will also be steadily deploying its many segmented mirror for infrared observations (an important detail as Webb is not a replacement for Hubble, which does most of its observations in the optical wavelengths).

Should deployment and placement go as planned, Webb will undoubtedly do ground-breaking astronomy, especially in the field of deep space cosmology. If anything should go wrong, any repair mission will take at a minimum five years to mount, if ever.

Keep those fingers and toes crossed!

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Astronomers discover white dwarf stars still burning hydrogen

9:50 am

The uncertainty of science: Using Hubble observations of the white dwarfs in two different globular clusters, astronomers have discovered that — contrary to the consensus opinion — some white dwarf stars are not slowly cooling embers of a dead star, but are still generating nuclear fusion by burning hydrogen in their outer layers.

Using Hubble’s Wide Field Camera 3 the team observed [globular clusters] M3 and M13 at near-ultraviolet wavelengths, allowing them to compare more than 700 white dwarfs in the two clusters. They found that M3 contains standard white dwarfs, which are simply cooling stellar cores. M13, on the other hand, contains two populations of white dwarfs: standard white dwarfs and those which have managed to hold on to an outer envelope of hydrogen, allowing them to burn for longer and hence cool more slowly.

Comparing their results with computer simulations of stellar evolution in M13, the researchers were able to show that roughly 70% of the white dwarfs in M13 are burning hydrogen on their surfaces, slowing down the rate at which they are cooling.

This discovery could have consequences for how astronomers measure the ages of stars in the Milky Way galaxy. The evolution of white dwarfs has previously been modeled as a predictable cooling process. This relatively straightforward relationship between age and temperature has led astronomers to use the white dwarf cooling rate as a natural clock to determine the ages of star clusters, particularly globular and open clusters. However, white dwarfs burning hydrogen could cause these age estimates to be inaccurate by as much as 1 billion years.

In other words, many past age estimates for star clusters could be very wrong, which in turn could mean the general understanding of the evolution of these objects could be very wrong as well.

These results also illustrate a fact that astronomers seem to always forget. The stars in any one category (white dwarfs, red super giants, yellow stars like the Sun, etc.) are not all identical, and thus their life and death processes will not all follow the predicted stages, like clockwork. Things are always far more complicated. Though the predictions might be broadly right, there will be many variations, so many that it will often be difficult to draw a generalized conclusion.

It seems that with white dwarfs astronomers have made this mistake, and now must rethink many of their conclusions.

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China’s Chang’e-5 orbiter returning to lunar space

9:25 am

The new colonial movement: In a somewhat bold move, Chinese engineers appear to now be shifting the Chang’e-5 orbiter so that it will be able to return to lunar space to fly past the Moon.

The orbiter, one of four distinct Chang’e-5 mission spacecraft, delivered a return module containing 1.731 kilograms of lunar samples to Earth Dec. 16 before firing its engines to deep space for an extended mission.

The Chang’e-5 orbiter later successfully entered an intended orbit around Sun-Earth Lagrange point 1, roughly 1.5 million kilometers, in March. There it carried out tests related to orbit control and observations of the Earth and Sun.

New data from satellite trackers now suggests Chang’e-5 has left its orbit around Sun-Earth L1 and is destined for a lunar flyby early September 9 Eastern time.

This data comes not from China but from amateur astronomers who specialize in tracking satellites.

The fly-by could provide the spacecraft the velocity it needs to reach near Earth asteroid Kamo’oalewa, which China has said it is targeting for a 2024 sample return mission. Such a reconnaissance will help them design the sample return mission.

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Ingenuity completes 13th flight

9:15 am

Ingenuity landing on September 5, 2021
Click for full image.

Though the full slate of images taken has not yet been released, it appears from the five images available that the thirteenth flight of Ingenuity on September 5, 2021 ended successfully. The photo to the right is the last available, and shows the helicopter’s shadow on the ground mere seconds before touch down. The landing legs’ shadows suggest it is oriented properly for that landing.

No word yet on how successful the flight itself was. The goal had been to fly back over the South Seitah area from a different angle and lower altitude, getting different perspectives of the ridges there to help plan Perseverance’s coming travels across that terrain.

The second picture below, cropped, reduced, and enhanced to post here, was taken about forty minutes before take-off by Perseverance and captures Ingenuity in the lower left, as indicated by the arrow.
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