Crater? Pit? Volcano?

Crater? Pit? Volcano?
Click for full image.

Cool image time! The photograph on the right, cropped to post here, was taken by the high resolution camera of Mars Reconnaissance Orbiter (MRO) on April 16, 2019 of the slope of a mountain inside a region dubbed Eridania that is part of the planet’s southern highlands.

The photograph, released as part of the June image release from MRO, came with no caption. Furthermore, the image title, “Eridania Mons,” provided no additional information, which is why I clicked on it. The vagueness of the title made me curious.

The full image shows a generally featureless plain. Near the image’s bottom however was the geological feature shown in the cropped section to the right. At first glance one thinks it is a crater. This first impression can’t be the entire story, because the feature is raised above the surrounding terrain, and in that sense is more like a small volcano with a caldera. The irregular pit inside the caldera kind of confirms this conclusion.

I would not bet much money on this conclusion. The overall terrain of the Eridania quadrangle is filled with craters, large and small. There does not seem to be any obvious evidence of past volcanic activity, and if there had been it has not expressed itself in large volcanoes.

However, other images of this mountain show many circular features that at first glance appear to be craters like the featured image. They appear slightly raised above the surrounding terrain, though not in as pronounced a manner.

They all could be small volcanoes. Or maybe they are impacts that hit a dense surface which prevented them from drilling too deep down, and instead caused the crater to be raised above the surrounding terrain.

‘Tis a puzzle. The irregular pit in this particular feature adds to the mystery. It does not look like the kind of pits one sees in calderas. Instead, its rough edge suggests wind erosion.

Sunspot update May 2019: The long ramp down

NOAA yesterday released its May update for the Sun’s sunspot cycle. The graph is posted below, annotated by me to give it some context.

The Sun in May continued to show the exact same amount of activity as it had shown for March and April. This steady uptick in sunspot activity once again shows that the ramp down to full solar minimum will be long and extended.

May 2019 sunspot activity

The graph above has been modified to show the predictions of the solar science community for the previous solar maximum. The green curves show the community’s two original predictions from April 2007, with half the scientists predicting a very strong maximum and half predicting a weak one. The red curve is their revised May 2009 prediction, extended in November 2018 four years into the future.

That we are definitely ramping downward to minimum, even with the slight increase in the past three months, is shown by the fact that the Sun has shown no sunspots for the past fifteen days. In fact, all the activity shown in May comes from the first half of the month. This pattern is actually a reflection of the Sun’s 27-day rotation period. As I noted in my February 2017 update,

January’s activity however illustrated a statistical phenomenon that is typical of the sunspot count. That count is determined not by the numbers of sunspots on the entire surface of the Sun, but on the sunspots visible on the side of the Sun facing the Earth. Since it is not unusual for one face to be more active than the other, as we transition from maximum to minimum the sunspot counts will often show a more pronounced up-and-down curve reflecting this fact. Since the Sun’s day equals about 27 Earth days, this means that about every two weeks the active side will dominate our view until it rotates away and the inactive side reveals itself for two weeks.

In 2017 the number of spots were greater, so the period of inactivity was generally less. Now, it is not unusual for the Sun to be blank for weeks at a time. When it does become active, it is also not unusual for that activity to be confined to one hemisphere, so we get two weeks or less of activity, followed by two weeks or more of blankness.

So far there have been no sunspots in June. Expect that to continue for at least another week, when the more active hemisphere of the Sun returns to face us. I would not be surprise however if that other hemisphere arrives with its sunspots gone, so that the present streak of blankness continues unabated.

Meanwhile, solar scientists struggle to figure out what is going to happen next. Unlike climate scientists, who know as little about the climate, the solar science community admits to its ignorance about the Sun, and the uncertainty of its solar models.

VLT snaps image of double asteroid zipping past Earth

Double asteroid imaged by VLT

The Very Large Telescope (VLT) in Chile was successfully able to photograph the double asteroid that flew past the Earth on May 25 at a distance of 3.2 million miles and a speed of 43 thousand miles per hour.

The left image on the right is the raw image, while the right image is their reconstruction after applying adaptive-optics (AO) to the raw image. From the press release:

Bin Yang, VLT astronomer, declared “When we saw the satellite in the AO-corrected images, we were extremely thrilled. At that moment, we felt that all the pain, all the efforts were worth it.” Mathias Jones, another VLT astronomer involved in these observations, elaborated on the difficulties. “During the observations the atmospheric conditions were a bit unstable. In addition, the asteroid was relatively faint and moving very fast in the sky, making these observations particularly challenging, and causing the AO system to crash several times. It was great to see our hard work pay off despite the difficulties!”

To put it mildly, that right image is a fantasy. Astronomers love to tout the wonders of adaptive optics, but no matter how good it might be, it still is garbage-in-garbage-out, a computer simulation based on their guess at what the object would look like if there was no atmosphere in the way. In this particular case, they are being especially fantastic, and guaranteed to be wrong. It is impossible for them to extrapolate such minute surface details from the fuzzy image on the left.

Still, getting an image of this asteroid as it zipped by at that speed using such a large telescope is an achievement, and bodes well for the use of ground-based astronomy of near Earth asteroids.

Republican senators move to stop Trump’s Mexico tariffs

The stupid party: A half dozen Republican senators have announced their opposition to the escalating tariffs Trump has imposed on Mexico designed to force that country to cooperate on gaining control of illegal immigration.

Joining [Chuck] Grassley [R-Iowa] in opposition to the tariffs were pro-trade Senate Republicans Pat Toomey of Pennsylvania, Martha McSally of Arizona, John Cornyn of Texas, Joni Ernst of Iowa and Rob Portman of Ohio, whose votes Trump will need to pass the USMCA.

This is the same pattern I’ve seen from Republicans for the past half century. Anytime anyone attempts to do anything that might clean up any of the mess we are in, a bunch jump in, for their own aggrandizement, to stymie it.

The article makes the claim that a border state like Arizona will be hurt by these tariffs. Bah. I live here, and see the harm the illegal immigration is actually doing. First, the flood of illegals is damaging the state’s natural environment, as they leave an incredible amount of trash throughout the wildernesses they travel.

Second, the flood has caused the government to make entering the U.S. a miserable and time-consuming experience for people doing it legally, one that is actually discouraging trade. You want to go to Mexico? You walk or drive across the border in seconds. You want to come back? Expect the wait to be one to two to three hours.

Third, the flood is distorting the market. Illegals have to work in the black market, which means they get badly taken advantage of. At the same time, their presence hurts legal workers, who can’t get work.

Fourth, and most important, the flood of illegals is fueling a rising contempt of the law, both by the illegals as well as American citizens. This in the long run is likely the worst consequence of the federal government’s inability to do its job here effectively.

And as usual, we have a lot of dumb Republicans who will team up with the partisan Democrats (who only want power) to block Trump’s effort, an effort that has already shown a positive effect and might actually fix the problem.

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