Tag: science

More delays threaten the Thirty Meter Telescope in Hawaii

9:48 pm

The coming dark age: The delaying tactics of the opponents to building the Thirty Meter Telescope in Hawaii has caused the consortium to announce that it now seriously considering moving the telescope to Spain’s Canary Islands.

These have been the most recent delaying tactics:

On Thursday, the Hawaii Senate approved a bill to ban new construction atop Mauna Kea, and included a series of audits and other requirements before the ban could be lifted. But House leaders said they don’t have plans to advance the bill. Democratic House Speaker Scott Saiki told the Honolulu Star-Advertiser that the “bill is dead on arrival in the House.”

There are also two appeals before the Hawaii Supreme Court. One challenges the sublease and land use permit issued by the Hawaii Board of Land and Natural Resources. The other has been brought by a Native Hawaiian man who says use of the land interferes with his right to exercise cultural practices and is thus entitled to a case hearing.

When the telescope gets moved, expect these barbarians in Hawaii to celebrate loudly, claiming their victory as a victory for “native rights.” What they will really be telling us is two things. First, they are against gaining new knowledge and new technology in a manner that does no one any harm. And two, they put racial rights above all, making them the worst sort of bigots.

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Is it a volcano or an impact crater? Mars Express wants to know!

9:58 am

Europe’s Mars Express orbiter has taken a high resolution image of Ismenia Patera, a very large crater located in the Arabia Terra region of Mars, the largest part of the transition zone between the low flat northern plains and the high rough southern terrain.

The crater is intriguing to scientists because they are not sure if it was created by an impact, or a volcano.

Certain properties of the surface features seen in Arabia Terra suggest a volcanic origin: for example, their irregular shapes, low topographic relief, their relatively uplifted rims and apparent lack of ejected material that would usually be present around an impact crater.

However, some of these features and irregular shapes could also be present in impact craters that have simply evolved and interacted with their environment in particular ways over time.

There is also additional evidence that this region was once home to volcanic activity. If so, that activity would have changed the terrain, and thus made its geological history more complex and difficult to decipher, a fact that is important since this is also a region that might have been at the edge of theorized northern Martian Ocean.

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Jupiter’s North Pole, as seen in infrared by Juno

9:06 am

The Juno science team has released an animation that shows, in infrared and in three dimensions, the storms of Jupiter’s north pole.

The link has three videos. One shows the gas giant’s surprisingly irregular magnetic field, as found by Juno. The first and third show a low and a high fly-over of the north pole, in infrared. I have embedded both fly-overs below the fold. First watch the high fly-over, which is the first video. This will make the low fly-over more understandable as it flies over the eight smaller storms that encircle the pole’s central vortex.
» Read more

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A Martian snake of collapsed hills

10:21 am

A Martian snake of collapsed hills

Close-up of collapsed hills

Time to once again delve into this month’s release of high resolution images from Mars Reconnaissance Orbiter. The image above, cropped, rotated, and reduced in resolution to post here, shows a string of strange mounds or hills, each with similar collapse features on their tops. If you click on the picture, you can see the full resolution image, rotated properly with north up. You can also go to the MRO post, which provides some additional information.

The white box indicates the location of the cropped close-up, at full resolution, to the right. This area is typical across the entire snake-like ridge. You have these mounds or hills, each with chaotic depressions at their tops. The depressions suggest that this ridge follows an underground void, like a lava tube. The ridge-like nature of the line of hills also suggest that this tube has been exposed by erosion over time, with the surrounding terrain more easily blown or washed away while the more resistant ridge remains.

At the same time, the line of hills is baffling. Why would a lava tube expand periodically to form something that looks like a string of pearls?

The location of this snaking ridge provides some additional context.
» Read more

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Issue with thermometers on Parker Solar Probe

8:56 am

As NASA prepares the Parker Solar Probe for its summer launch, engineers are reviewing an issue with the spacecraft’s thermometers.

As those preparations continue, officials are studying problems with devices known as platinum resistance thermometers that are part of the spacecraft’s thermal control system. Those devices have suffered a higher-than-expected failure rate, according to a presentation at an April 5 meeting of NASA’s Heliophysics Advisory Committee.

The thermometers are lightweight, highly sensitive temperature sensors used to help provide feedback to the spacecraft’s cooling system and solar arrays, NASA spokesman Dwayne Brown said April 9. “We put all spacecraft through a rigorous test program to make sure all systems are working as designed and it is normal for a test program to uncover issues.”

“The team is looking very carefully at whether any change is needed,” Peg Luce, acting director of NASA’s heliophysics division, said at the meeting. The issue, she said, was debated “quite significantly” at a review last week to approve the shipment of the spacecraft to Florida, including whether to delay that shipment to study the problem. “There are certain, possible fixes if we need to fix something that could be done at the Cape, so the decision was to go ahead and ship,” she said.

This issue is especially critical as the spacecraft is intended to fly as close as four million miles from the Sun. If these thermometers fail too easily, the spacecraft will not be able to monitor its temperature properly, and it will likely fail much sooner than planned.

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Europe’s Trace Gas Orbiter achieves operational orbit around Mars

8:33 am

After a year of aerobraking to lower its orbit, the European Space Agency’s Trace Gas Orbiter has reached its planned orbit around Mars, and is about to begin studying the red planet’s atmosphere.

The primary goal is to take a detailed inventory of trace gases – those that make up less than 1% of the total volume of the planet’s atmosphere. In particular, the orbiter will seek evidence of methane and other gases that could be signatures of active biological or geological activity.

On Earth, living organisms release much of the planet’s methane. It is also the main component of naturally occurring hydrocarbon gas reservoirs, and a contribution is also provided by volcanic and hydrothermal activity. Methane on Mars is expected to have a rather short lifetime – around 400 years – because it is broken down by ultraviolet light from the Sun. It also reacts with other species in the atmosphere, and is subject to mixing and dispersal by winds. That means, if it is detected today, it was likely created or released from an ancient reservoir relatively recently. Previous possible detections of methane by ESA’s Mars Express and more recently by NASA’s Curiosity rover have been hinted at, but are still the subject of much debate.

The Trace Gas Orbiter can detect and analyse methane and other trace gases even in extremely low concentrations, with an improved accuracy of three orders of magnitude over previous measurements. It will also be able to help distinguish between the different possible origins. [emphasis mine]

The highlighted sentence is important. Pinpointing a region where methane is concentrated will allow scientists to better understand where it is coming from, and what is causing its release. It could be microbiological life, but it also could be from active volcanic processes. Finding either or both would be significant, to put it mildly.

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Sunspot update for March 2018: the sun crashes!

11:49 am

It surely looks like the solar minimum has arrived, and it has done so far earlier than expected! On Sunday NOAA posted its monthly update of the solar cycle, covering sunspot activity for March 2018. Below is my annotated version of that graph.

March 2018 was the least active month for sunspots since the middle of 2009, almost nine years ago. In fact, activity in the past few months has been so low it matches the low activity seen in late 2007 and early 2008, ten years ago when the last solar minimum began and indicated by the yellow line that I have added to the graph below. If the solar minimum has actually arrived now, this would make this cycle only ten years long, one of the shortest solar cycles on record. More important, it is a weak cycle. In the past, all short cycles were active cycles. This is the first time we have seen a short and weak cycle since scientists began tracking the solar cycle in the 1700s, following the last grand minimum in the 1600s when there were almost no sunspots.
» Read more

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Revisiting Biosphere 2

1:22 pm

Biosphere 2

This week Diane and I have a friend visiting from back east. As locals generally do when guests visit, we used this visit as an excuse to go sightseeing at local attractions that we somehow never got the time to visit on our own.

So on Tuesday we drove north to take a tour of Biosphere 2, what has been called “a giant space-age ark in the middle of the desert.” The idea, as sold heavily to the public when it was built in the late 1980s and early 1990s, was that eight people would try to live in a closed system for two years, demonstrating the technology needed to both build colonies on other worlds as well as protect the environment here on Earth.

The system wasn’t really closed however (power came from outside), and during the first two year mission it seemed they were somewhat lax about keeping the system closed.

One Biospherian accidentally cut off the tip of her finger and left for medical care. When she returned, she carried in two duffle bags of supplies to the supposedly self-sustaining environment (which presumably would not have been feasible on, say, Mars).

There were also financial issues, as mentioned by our tour guide and confirmed by news stories. Its backer, Texas oil man Edward Bass, spent somewhere between $150 to $200 million. It seems however that the managers running Biosphere 2 didn’t keep good books, and when Bass asked for an accounting they couldn’t provide it. Instead, they attempted to sabotage the project’s second mission.
» Read more

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A spray of volcanic ejecta on Mars?

10:38 am

pit features on floor of crater

Time for some more weird Mars geology! Today the science team for the high resolution camera on Mars Reconnaissance Orbiter released its monthly batch of new images. There is a lot of interesting stuff buried therein, some of which I will feature periodically in the next month.

The image on the right, reduced in resolution to post here, is a good example. (If you click on the image you can see the full resolution version.) It shows a scattering of pits in three specific areas on the crater floor, all in a line going from the northeast to the southwest. Yet, the rest of the crater floor lacks similar pits, and is either very smooth or has a mottled appearance. Both the smooth and the mottled areas appear to have a very faint trend going from the northwest to the southeast, which to my eye appears caused by the general wind direction that flows across the crater floor.

Even more intriguing, the pits in these three areas appear to be mostly oblong and also trend from the northeast to the southwest, cutting across the general trend of the rest of the crater floor. You can see this in the cropped closeups from the full resolution image below, showing the two boxed areas indicated on the image on the right.
» Read more

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Astronomers find a dozen black holes near center of Milky Way

8:40 am

Astronomers have discovered a dozen smaller black holes orbiting near Sagittarius A* (pronounced “A-star”), the supermassive black hole at the center of the Milky Way.

Charles Hailey from Columbia University in New York and colleagues used archival data from Nasa’s Chandra X-ray telescope to come to their conclusions. They report the discovery of a dozen inactive and low-mass “binary systems”, in which a star orbits an unseen companion – the black hole.

The supermassive black hole at the centre of the Milky Way, known as Sagittarius A* (Sgr A*), is surrounded by a halo of gas and dust that provides the perfect breeding ground for the birth of massive stars. These stars live, die and could turn into black holes there. In addition, black holes from outside the halo are believed to fall under the influence of Sgr A* as they lose their energy, causing them to be pulled into its vicinity, where they are held captive by its force. Some of these bind – or “mate” – to passing stars, forming binary systems.

They have extrapolated their data to predict the existence of thousands more of these small black holes near the galaxy’s center.

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Sightseeing

8:48 am

Biosphere-2

Posting has been light the past few days, and will be today, because we have a friend visiting from back east. This of course provides an excuse to do some sightseeing. Yesterday we visited Biosphere-2, the first time I have ever been there, as shown in the picture above. Today we are heading down to Bisbee, Arizona.

I plan to write up my impressions of Biosphere-2 tomorrow. Stay tuned!

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Near the Martian shoreline

1:20 pm

One of the prime areas of research for Mars planetary geologists is the region on Mars where the geography appears to transition from the southern cratered, rough terrain to the northern low, generally smooth, and flat plains. It is theorized by some scientists that the northern plains were once an ocean, probably shallow and probably intermittent, but wet nonetheless for considerable periods. The global map of Mars below, created by the laser altimeter on Mars Global Surveyor, clearly shows the obvious elevation differences between the low northern plans (blue) and the high, more cratered southern regions (changing from yellow to orange as you move higher).

Labeled global Map of Mars

Scientists have spent a considerable effort studying this transition zone (green on the map), illustrated by just one example I recently highlighted, showing that, though there does not appear to be a clear shoreline in many places, there is strong evidence that a shallow ocean repeatedly rose and fell in this transition zone, leaving behind geological ripple marks vaguely reminiscent of those seen on a beach caused by the rise and fall of the tides.

Today we highlight another example, taken in January 2018 at the location indicated by the cross on the above map.
» Read more

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Hubble finds galaxy with no evidence of dark matter

12:29 pm

The uncertainty of science: Using the Hubble Space Telescope astronomers have discovered a nearby galaxy that apparently has little or no evidence of dark matter.

The unique galaxy, called NGC 1052-DF2, contains at most 1/400th the amount of dark matter that astronomers had expected. The galaxy is as large as our Milky Way, but it had escaped attention because it contains only 1/200th the number of stars. Given the object’s large size and faint appearance, astronomers classify NGC 1052-DF2 as an ultra-diffuse galaxy. A 2015 survey of the Coma galaxy cluster showed these large, faint objects to be surprisingly common.

But none of the ultra-diffuse galaxies discovered so far have been found to be lacking in dark matter. So even among this unusual class of galaxy, NGC 1052-DF2 is an oddball.

Van Dokkum and his team spotted the galaxy with the Dragonfly Telephoto Array, a custom-built telescope in New Mexico they designed to find these ghostly galaxies. They then used the W.M. Keck Observatory in Hawaii to measure the motions of 10 giant groupings of stars called globular clusters in the galaxy. Keck revealed that the globular clusters were moving at relatively low speeds, less than 23,000 miles per hour. Stars and clusters in the outskirts of galaxies containing dark matter move at least three times faster. From those measurements, the team calculated the galaxy’s mass. “If there is any dark matter at all, it’s very little,” van Dokkum explained. “The stars in the galaxy can account for all the mass, and there doesn’t seem to be any room for dark matter.”

The galaxy is unusual in many other ways.

The Hubble images also revealed the galaxy’s unusual appearance. “I spent an hour just staring at the Hubble image,” van Dokkum recalled. “It’s so rare, particularly these days after so many years of Hubble, that you get an image of something and you say, ‘I’ve never seen that before.’ This thing is astonishing: a gigantic blob that you can look through. It’s so sparse that you see all of the galaxies behind it. It is literally a see-through galaxy.”

The ghostly galaxy doesn’t have a noticeable central region, or even spiral arms and a disk, typical features of a spiral galaxy. But it doesn’t look like an elliptical galaxy, either. The galaxy also shows no evidence that it houses a central black hole. Based on the colors of its globular clusters, the galaxy is about 10 billion years old. Even the globular clusters are oddballs: they are twice as large as typical stellar groupings seen in other galaxies.

The bottom line here is that we have only circumstantial evidence that dark matter exists, based solely on the fact that in all other measured galaxies, the outer stars rotate much faster than they should. That rotation speed however does not guarantee the existence of dark matter, only that something is causing the fast rotation. And the lack thereof in this galaxy puts a big crimp in the theory that dark matter exists, since the theories that posit its existence almost require it to be present in every galaxy.

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The James Webb Telescope: a signpost for identifying fake news sources

11:35 am

The news yesterday that NASA will once again have to delay the launch of the James Webb Space Telescope due to a variety of technical issues and management errors not only exemplified the fundamental failure of the federal government, it also illustrated the routine failures of today’s mainstream press.

First, Webb’s new delay epitomizes the systemic incompetence of Washington. Despite being 13 years behind schedule and costing eight times more than originally planned, NASA and its contractors still couldn’t get things right.

Most of the problems have occurred with the spacecraft half of the project, which was built by Northrop Grumman in California and is undergoing testing there. During the teleconference, NASA officials, including acting Administrator Robert Lightfoot, expanded upon technical problems first reported publicly by the agency’s inspector general last month.

These include leaky valves within the spacecraft’s propulsion system and difficulties encountered during deployment tests of the sun shield. Not only did the thin, five-layer sun shield snag during the deployment, but technicians also found seven tears up to 10cm long within the material. NASA and Northrop Grumman have identified fixes for these problems, but their repair has added months of delays to the project, and engineers cannot be sure that more issues will not crop up during further testing.

Such failures, in NASA and in all big federal projects in recent years, are hardly news. Only the willfully blind or those who support wasting tax dollars to distribute pork will deny they exist.

The failures of the federal government however is not the focus of this essay. Instead, the announcement yesterday and the coverage of it by the press provides us a perfect and very obvious signpost for differentiating between the fake news sources that are generally unreliable or too often allow their biases to influence their reporting, and those sources that do a good job.

That signpost is one simple fact: Webb is not a replacement or successor to the Hubble Space Telescope, despite NASA making this false claim for decades. Hubble is an optical telescope. Webb will view the universe in the infrared. These are too entirely different things.

Yet, too many news sources today repeated NASA’s false claim, illustrating how little they know about both telescopes and their design, while revealing their complete inability to do some basic journalistic research. Instead they merely rewrite old press releases, and thus prove clearly by their bad reporting why so many people have so little respect for the modern press.

The worst examples made this false claim right in the headline:
» Read more

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Webb telescope delayed again to 2020

10:34 am

NASA has announced that it is once again delaying the launch of the James Webb Space Telescope, from 2019 to 2020.

The observatory was supposed to fly this year. But last fall, NASA bumped the launch to 2019. NASA announced the latest delay on Tuesday. “We have one shot to get this right before going into space,” said Thomas Zurbuchen, NASA’s associate administrator of science. He said some mistakes were made while preparing the telescope, and NASA underestimated the scale of the job. [emphasis mine]

None of this is a surprise. Webb is more pork than science. It was originally budgeted at $1 billion, with a planned launch in 2011. It will now cost more than $9 billion, and be delayed almost a decade. Since the project began in the early 2000s, by the time it launches it will have been in development for almost two decades, which is almost a lifetime career for some people.

And note, the article includes the lie that Webb is “a successor to the Hubble Space Telescope.” It is not. Hubble is an optical telescope. Webb will only look in the infrared. These are very different things.

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Tabby’s Star dims again

8:37 am

Scientists studying Tabby’s Star have revealed that it suddenly dimmed last week, the most since 2013, and then just as quickly returned almost to normal.

The latest dimming event started with a slow decline and ended with a rapid increase in brightness, Boyajian and her team wrote on their blog. Dust from a backward comet tail and then larger chunks from the broken-up body would explain that uneven pattern.

At this time the evidence clearly points not to alien megastructures but to clouds of fine dust whose structure and origin remain puzzling.

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India delays Chandrayaan-2 six months

5:46 pm

Because engineers wished more time, India has delayed the launch of its second unmanned Moon mission, Chandrayaan-2, from April to October.

Union Minister of State in the Prime Minister’s Office, in-charge of the Department of Space, Jitendra Singh had on 16 February last said the lunar mission under which the Isro will for the first time attempt to land a rover on the moon’s south pole, will be launched in April.

Sivan (head of ISRO) had earlier said the window to launch the Rs800 crore mission was between April and November 2018. While the “targeted date” was April, Isro would launch the mission in October or November, he had said.

This is a very ambitious mission, so pushing the launch back to October seems quite reasonable. That they are aiming for the south pole is also smart, especially since NASA has abandoned that location as a target to instead build a giant Potemkin village orbiting the Moon, where it can accomplish nothing.

Posted between Flagstaff and Phoenix as we head back from a very successful four-day caving expedition in the Grand Canyon.

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Mars rover update: March 21, 2018

2:10 pm

Summary: Curiosity continues its exploration of Vera Rubin Ridge, including several drilling attempts. Opportunity is halfway down Perseverance Valley.

For a complete list of all past updates going back to July 2016, see my February 8, 2018 update.

Curiosity

Curiosity's traverse map, Sol 1993

For the overall context of Curiosity’s travels, see Pinpointing Curiosity’s location in Gale Crater.

Since my February 8, 2018 update, the Curiosity science team has apparently been loath to leave Vera Rubin Ridge. They had begun the trek to the northeast that would take them towards the exit ridge heading to the southeast, as indicated by the dotted red line on the traverse map above, but then continued past that planned route to continue to the northeast. Along the way they attempted to drill twice using an improvised approach that they hoped would bypass the drill’s stuck feed mechanism, without apparent success.

The panorama below is looking to the west and south, as indicated by the yellow lines in the image above.
» Read more

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Star’s close approach 70,000 years ago pinned to cometary orbits

10:03 am

Astronomers now think they have pinned the orbits of about 340 comets to another star’s close approach to our solar system 70,000 years ago.

About 70,000 years ago, when the human species was already on Earth, a small reddish star approached our solar system and gravitationally disturbed comets and asteroids. Astronomers from the Complutense University of Madrid and the University of Cambridge have verified that the movement of some of these objects is still marked by that stellar encounter. At a time when modern humans were beginning to leave Africa and the Neanderthals were living on our planet, Scholz’s star – named after the German astronomer who discovered it – approached less than a light-year from the Sun. Nowadays it is almost 20 light-years away, but 70,000 years ago it entered the Oort cloud, a reservoir of trans-Neptunian objects located at the confines of the solar system.

This discovery was made public in 2015 by a team of astronomers led by Professor Eric Mamajek of the University of Rochester (USA). The details of that stellar flyby, the closest documented so far, were presented in The Astrophysical Journal Letters.

Now two astronomers from the Complutense University of Madrid, the brothers Carlos and Raúl de la Fuente Marcos, together with the researcher Sverre J. Aarseth of the University of Cambridge (United Kingdom), have analyzed for the first time the nearly 340 objects of the solar system with hyperbolic orbits (very open V-shaped, not the typical elliptical), and in doing so they have detected that the trajectory of some of them is influenced by the passage of Scholz´s star.

It is likely that the close approach influenced a lot more objects, many of which might not have yet arrived in the inner solar system. Moreover, their computer models suggest that the star might have come closer to the Sun than 0.6 light years.

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New theory suggests Mars’ oceans formed earlier and intermittently

11:19 am

Scientists have proposed a new model for the existence of oceans on Mars’ northern plains that proposes they formed earlier, were shallower, were variable in size, and formed in conjunction with the eruptions that formed the planet’s giant volcanoes.

The proposal by UC Berkeley geophysicists links the existence of oceans early in Mars history to the rise of the solar system’s largest volcanic system, Tharsis, and highlights the key role played by global warming in allowing liquid water to exist on Mars. “Volcanoes may be important in creating the conditions for Mars to be wet,” said Michael Manga, a UC Berkeley professor of earth and planetary science and senior author of a paper appearing in Nature this week and posted online March 19.

…The new model proposes that the oceans formed before or at the same time as Mars’ largest volcanic feature, Tharsis, instead of after Tharsis formed 3.7 billion years ago. Because Tharsis was smaller at that time, it did not distort the planet as much as it did later, in particular the plains that cover most of the northern hemisphere and are the presumed ancient seabed. The absence of crustal deformation from Tharsis means the seas would have been shallower, holding about half the water of earlier estimates. “The assumption was that Tharsis formed quickly and early, rather than gradually, and that the oceans came later,” Manga said. “We’re saying that the oceans predate and accompany the lava outpourings that made Tharsis.”

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Scientists theorize that Oumuamua came from a binary star system

8:17 am

Based on statistics and computer modeling, some scientists believe that the interstellar object Oumuamau likely came from stellar binary system.

For the new study, published in the journal Monthly Notices of the Royal Astronomical Society, Jackson and his co-authors set about testing how efficient binary star systems are at ejecting objects. They also looked at how common these star systems are in the Galaxy. They found that rocky objects like ‘Oumuamua are far more likely to come from binary than single star systems. They were also able to determine that rocky objects are ejected from binary systems in comparable numbers to icy objects.

Their conclusion does make sense, though any good scientist would retain a gigantic sense of skepticism. While it is statistically reasonable to conclude that a majority of interstellar objects should come from binary systems, there is no guarantee that Oumuamua in particular did so. Even if the odds were one in a million, there is always that one, and the universe often seems prone to fooling us.

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North American mountains get 3Xs the snow previously estimated

8:30 am

The uncertainty of science: A new analysis based on computer models suggests that the mountains of North America get three times more snow each year than scientists has previously estimated.

Those figures come thanks to a new analysis in which researchers used computer simulations to estimate the typical annual snowfall in each of 11 North American mountain ranges. After supercomputer simulations of regional climate that would have taken 50 years on the average laptop, the team found that those mountain ranges receive about 3018 cubic kilometers of snow a year. Although those ranges together cover only about 25% of the area stretching from the Arctic Ocean down to Mexico’s southern border, they get about 60% of its snow, the researchers report in Geophysical Research Letters. That’s nearly three times the estimate for mountain snow from one previous study, the team notes.

First, this is based on computer simulations, not actual data in the field. I wouldn’t put much money on it. Second, it does show us how little climate scientists really know about the climate, as this simulation is still using all the knowledge they have, and it comes up with a conclusion that confounds them. Third, I was astonished the article didn’t try to push the idea that this larger estimate should be blamed on human-caused global warming. It didn’t, which I suppose is a sign of some progress.

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Dawn finds recent changes on Ceres

4:28 pm

New data from Dawn has found at least one spot on Ceres where recent changes appear to have occurred on the surface.

Observations obtained by the visible and infrared mapping spectrometer (VIR) on the Dawn spacecraft previously found water ice in a dozen sites on Ceres. The new study revealed the abundance of ice on the northern wall of Juling Crater, a crater 12 miles (20 kilometers) in diameter. The new observations, conducted from April through October 2016, show an increase in the amount of ice on the crater wall. “This is the first direct detection of change on the surface of Ceres,” said Andrea Raponi of the Institute of Astrophysics and Planetary Science in Rome.

Raponi led the new study, which found changes in the amount of ice exposed on the dwarf planet. “The combination of Ceres moving closer to the sun in its orbit, along with seasonal change, triggers the release of water vapor from the subsurface, which then condenses on the cold crater wall. This causes an increase in the amount of exposed ice. The warming might also cause landslides on the crater walls that expose fresh ice patches.”

There is a certain irony here. For eons, the only alien body that humans were able to get a good look at, the Moon, was also an object where almost nothing changed. Even today, after humans have visited its surface and numerous orbiting spacecraft have photographed its surface in numbing detail, the Moon has generally been found to be stable and unchanging. Though impacts do occur, and the surface does evolve over time, the Moon is probably one of the most static bodies in the solar system.

The irony is that this lunar stability gave us an incorrect impression of the rest of the solar system. Based on the Moon, it was assumed that airless or almost airless bodies like Mercury, Mars, Pluto, the large moons of Jupiter and Saturn, and asteroids like Ceres would also be stable and unchanging. What we have instead found is that the Moon is the exception that proves the rule. Most of these other worlds are unlike the Moon. They show a lot of surface evolution, over relatively short time scales. They change.

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Kepler to run out of fuel in the coming months

1:08 pm

After nine years of success, the Kepler space telescope is running out of fuel, which will force an end to the mission sometime in the next several months.

The Kepler team is planning to collect as much science data as possible in its remaining time and beam it back to Earth before the loss of the fuel-powered thrusters means that we can’t aim the spacecraft for data transfer. We even have plans to take some final calibration data with the last bit of fuel, if the opportunity presents itself.

Without a gas gauge, we have been monitoring the spacecraft for warning signs of low fuel— such as a drop in the fuel tank’s pressure and changes in the performance of the thrusters. But in the end, we only have an estimate – not precise knowledge. Taking these measurements helps us decide how long we can comfortably keep collecting scientific data.

They are doing a dance here. If they run out of fuel while collecting data, that data will be lost. If they stop collecting data too soon, however, to transmit it to Earth, they will not maximize the data obtained.

Meanwhile, the next exoplanet hunter, TESS, is scheduled for launch on April 16 on a Falcon 9 rocket.

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Chandra looks back at the Crab Nebula

8:22 am

Link here. It is almost twenty years since the Chandra X-Ray Observatory was launched, and in celebration the science team have released another X-ray image of the Crab Nebula, taken in 2017 in league with an optical image from the Hubble Space Telescope and an infrared image from the Spitzer Space Telescope. They have also provided links to all similar past images, going back to 1999.

Some of the images are actually videos, in 2002 and 2011, showing the Crab’s dynamic nature. You can actually see flares and waves of radiation rippling out from its center.

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New Horizons team picks Ultima Thule as nickname for 2014 MU69

5:27 pm

In their continuing effort to give interesting names to their targets, the New Horizons team has chosen the name Ultima Thule for 2014 MU69, the Kuiper Belt object it will fly past on January 1, 2019.

With substantial public input, the team has chosen “Ultima Thule” (pronounced ultima thoo-lee”) for the Kuiper Belt object the New Horizons spacecraft will explore on Jan. 1, 2019. Officially known as 2014 MU69, the object, which orbits a billion miles beyond Pluto, will be the most primitive world ever observed by spacecraft – in the farthest planetary encounter in history.

Thule was a mythical, far-northern island in medieval literature and cartography. Ultima Thule means “beyond Thule”– beyond the borders of the known world—symbolizing the exploration of the distant Kuiper Belt and Kuiper Belt objects that New Horizons is performing, something never before done.

“MU69 is humanity’s next Ultima Thule,” said Alan Stern, New Horizons principal investigator from Southwest Research Institute in Boulder, Colorado. “Our spacecraft is heading beyond the limits of the known worlds, to what will be this mission’s next achievement. Since this will be the farthest exploration of any object in space in history, I like to call our flyby target Ultima, for short, symbolizing this ultimate exploration by NASA and our team.”

Their spacecraft will be the first to see this object up close. It is their right to name it. And if the International Astronomical Union objects, they can go to hell. I guarantee that future generations of space-farers will know this tiny world by this name, and this name alone.

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An even more spectacular movie of Jupiter’s storms

8:45 am

Cool image time! Yesterday I posted a short gif created by citizen scientist Gerald Eichstädt, using twelve Juno images, that showed some cloud changes over time. Today, I discovered that Eichstädt has created an even more spectacular movie, which I have embedded below the fold, based on images taken during Juno’s tenth close fly-by.

This movie shows the short-term dynamics Jupiter’s southern storms derived from raw JunoCam images of Juno’s Perijove-10 flyby on Dec 16, 2017.

You might also notice the effect of changing solar illumination on the appearance of the haze bands. JunoCam usually takes a time-lapse sequence of images during each perijove showing Jupiter’s polar regions. These images are taken from different perspectives along Juno’s trajectory. But it’s possible to reproject the JunoCam images to a common perspective. Displaying such a sequence rapidly reveals cloud motion in Jupiter’s storm systems.

This movie applies this technique. At the same time, it is changing the simulated perspective along Juno’s trajectory. The same short sequence of images is displayed in a loop, but due to the changing way of reprojecting the raw images, the shown surface area is changing more or less continuously.

Eichstädt warns that the blinking nature of the film might make it unsuitable for those with epilepsy. If this is not an issue for you, you should then definitely take a look.
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A Juno movie of cloud motions

9:12 am

Cool image time! Citizen scientist Gerald Eichstädt, using twelve Juno images, has compiled a short gif movie that shows a tiny amount of cloud movement.

I think this is one of the first times Juno has show us even a tiny bit of cloud evolution, information that is essential for gaining a true understanding of Jupiter’s slightly less than 2000 mile deep atmosphere. To see it, go to the link. As Eichstadt notes, “Individual images are noisy, but we see cloud motion.”

When you watch, zoom in on the upper right quarter. This is the area that the cloud motion is seen best.

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Martian craters go splat!

2:17 pm

Overview of the volcanic Tharsis Bulge on Mars

Cool image time! In continuing my exploration of this month’s Mars Reconnaissance Orbiter (MRO) image release, I found two interesting images of small craters, one as part of that image release, the other found completely by accident.

The map on the right, taken from the MRO HiRISE archive page, shows the locations of these two images. Both are located in the lava plains that surround the giant volcano Pavonis Mons, the central volcano of the three volcanoes to the east of Olympus Mons. Previously, I have done posts focusing specifically on both Pavonis Mons and Arsia Mons. Not only is the geology of these gigantic volcanoes fascinating, there is evidence that ancient glacial ice lurks in lava tubes on their slopes, making them potentially prime real estate for future explorers.

The first image, labeled #1 on the image above, was taken in January 2018 to get a better look at a small crater on the surrounding lava plains, and was part of the MRO March image release. I have cropped it to post here, focusing on the crater itself.

My first reaction on seeing the image was, “Did this impact not go splat when it hit?”
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