Tag: science

Titan’s fizzy oceans?

11:36 am

New research suggests that the hydrocarbon lakes of Titan might periodically fizz with nitrogen bubbles.

A recent NASA-funded study has shown how the hydrocarbon lakes and seas of Saturn’s moon Titan might occasionally erupt with dramatic patches of bubbles.

For the study, researchers at NASA’s Jet Propulsion Laboratory in Pasadena, California, simulated the frigid surface conditions on Titan, finding that significant amounts of nitrogen can be dissolved in the extremely cold liquid methane that rains from the skies and collects in rivers, lakes and seas. They demonstrated that slight changes in temperature, air pressure or composition can cause the nitrogen to rapidly separate out of solution, like the fizz that results when opening a bottle of carbonated soda.

These results might help explain the mysterious islands that seem to appear and disappear and then reappear in Titan’s lakes. Rather than islands, they might be patches of nitrogen bubbles.

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Saturn’s weird moon Pan

9:34 am

Pan

New images from Cassini have provided scientists their first sharp images of Saturn’s moon Pan, and what those images show is something really weird. The image on the right is only one sample, with the link providing more.

Pan orbits in a gap between two rings, and the ridge might have accumulated from material from those rings. Then again, maybe not. It will take more data to I think completely unravel how this moon got to look like it does.

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At the crest

12:15 pm

Looking north at the crest

Cool images time! The image above, cropped and reduced to show here, is a panorama that I have created from the most recent images sent down from Opportunity yesterday. The rover sits on the crest of the rim of Endeavour Crater, and this panorama looks north at that crest, back in the direction where the rover has come. The rovers tracks can be seen fading away into the distance slightly to the left of the crestline..If you click on the picture you can see the full resolution image.

The crater floor is to the right, the plains that surround the crater are to the left.

Below is another panorama, created by me from the same images sent down today, this time looking south at the crest in the direction Opportunity is heading. Once again, if you click on the picture you can see the full resolution version.

The full set of today’s images from Opportunity suggest that the science team took them to assemble a full 360 degree panorama before they begin the journey south to the gully that is just now becoming visible at the southernmost edge of the most recent overhead traverse image. To get to that gully they will now have to descend off the crest and down outside the rim of Endeavour Crater, moving to the right in the panorama below. This is therefore their last opportunity for awhile to get a good view from a high overlook.

Looking south at the crest

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Sunspot update for February 2017

10:04 am

On Sunday NOAA posted its monthly update of the solar cycle, covering sunspot activity for February. As I have been doing every month since 2010, I am posting it here with annotations to give it context.

February 2017 Solar Cycle graph

The graph above has been modified to show the predictions of the solar science community. 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.

The decline in sunspots continues. Though the increase in activity from January held in February, the overall activity remains significantly below the predictions, and continues to point to a much earlier arrival of the solar minimum, sometime in 2019.

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Scientists estimate age of bright spots in Occator Crater on Ceres

8:22 am

Using crater counts and a careful analysis of features in Occator Crater on Ceres, scientists have estimated that the last major eruption occurred about 4 million years ago.

Nathues and his team interpret the central pit with its rocky, jagged ridge as a remnant of a former central mountain. It formed as a result of the impact that created Occator Crater some 34 million years ago and collapsed later. The dome of bright material is much younger: only approximately four million years. The key to determining these ages was the accurate counting and measuring of smaller craters torn by later impacts. This method’s basic assumption is that surfaces showing many craters are older than those that are less strongly “perforated”. Since even very small craters are visible in highly resolved images, the new study contains the most accurate dating so far.

“The age and appearance of the material surrounding the bright dome indicate that Cerealia Facula was formed by a recurring, eruptive process, which also hurled material into more outward regions of the central pit”, says Nathues. “A single eruptive event is rather unlikely,” he adds. A look into the Jupiter system supports this theory. The moons Callisto and Ganymede show similar domes. Researchers interpret them as volcanic deposits and thus as signs of cryovolcanism.

The volcano itself has slumped away, leaving behind the bright depression. Whether any cryovolcanism is still occurring underground remains unknown.

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Cuts to NOAA, EPA, and the environmental bureaucracy

8:57 am

Two articles today outline some of the proposed cuts the Trump administration is considering for the EPA and NOAA and their generally bloated and politicized administrative bureaucracies.

The first article focuses on the proposed cuts to the EPA, which would reduce the overall budget to that agency by about 25%.

The Trump administration wants to cut spending by EPA’s Office of Research and Development (ORD) by more than 40% from roughly $510 million to $290 million, according to sources that have seen preliminary directives from the White House’s Office of Management and Budget (OMB). The cuts target scientific work in fields including climate change, air and water quality, and chemical safety. EPA’s $50 million external grant program for environmental scientists at universities would disappear altogether. Such erasures represent just part of a larger plan to shrink EPA’s budget by 25% to $6.1 billion, and cut its workforce by 20% to 12,400 employees, in the 2018 fiscal year that begins 1 October.

The second article focuses on proposed cuts aimed at NOAA and within the Commerce Department, with cuts in specific departments ranging from 5% to 26%, with an overall cut to NOAA of 17%.
» Read more

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A propeller in Saturn’s A ring

3:45 pm

A propeller in Saturn's A ring

Cool image time! The image on the right, cropped and reduced to show here, captures the same propeller feature in Saturn’s A ring, with the top image showing the sunlight side and the bottom image the side away from the Sun.

Cassini scientists have been tracking the orbit of this object for the past decade, tracing the effect that the ring has upon it. Now, as Cassini has moved in close to the ring as part of its ring-grazing orbits, it was able to obtain this extreme close-up view of the propeller, enabling researchers to examine its effects on the ring. These views, and others like them, will inform models and studies in new ways going forward.

…The propeller’s central moonlet would only be a couple of pixels across in these images, and may not actually be resolved here. The lit-side image shows that a bright, narrow band of material connects the moonlet directly to the larger ring, in agreement with dynamical models. That same thin band of material may also be obscuring the moonlet from view.

Lengthwise along the propeller is a gap in the ring that the moonlet has pried open. The gap appears dark on both the lit and unlit sides. Flanking the gap near the moonlet are regions of enhanced density, which appear bright on the lit side and more mottled on the unlit side.

The scale of the two images is slightly different, 0.33 and 0.44 miles, as they were taken as Cassini was zipping past during one of its ring-grazing orbits on February 21.

To my eye, the effect here faintly resembles a wake produced by a boat in water, except that the wake moves in opposite directions on opposite sides of the tiny moonlet as it plows through the A ring.

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Two of five cameras on Japan’s Venus orbiter Akatsuki shut down

12:08 pm

Japan has been forced to shut down operation on two of the five cameras on its Venus orbiter Akatsuki.

They think the problem has been caused by the additional five years required to get into Venus orbit when its main engine failed to fire during the first orbital attempt in 2010. During those five years the spacecraft was exposed to more radiation that expected, possibly damaging its equipment.

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Asteroid breaks in two, each piece develops a tail

2:08 pm

Astronomers have discovered a main belt asteroid that six years ago broke in two, after which both pieces developed tails resembling comets.

“The results derived from the evolution of the orbit show that the asteroid fragmented approximately six years ago, which makes it the youngest known asteroid pair in the Solar System to date,” says Fernando Moreno, researcher at the Institute of Astrophysics of Andalusia (IAA-CSIC), in charge of the project.

P/2016 J1 presents another important peculiarity, which makes it very unusual. “Both fragments are activated, i.e., they display dust structures similar to comets. This is the first time we observe an asteroid pair with simultaneous activity,” says Fernando Moreno (IAA-CSIC).

Analyses revealed that the asteroids were activated near their perihelion – the point on the orbit nearest to de Sun – between the end of 2015 and the beginning of 2016, and that they remained for a period of between six and nine months. The span of time between the moment of fragmentation and their bout of activity implies that the two events are not related. In fact, the data suggests that the fragmentation also happened near the perihelion but during the previous orbit (it takes P/2016 J1 5.65 years to spin around the Sun). “In all likelihood, the dust emission is due to the sublimation of ice that was left exposed after the fragmentation,” says Moreno (IAA-CSIC).

I suspect that the more we learn about asteroids and comets the more we will blur the line that separates them.

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The winds of Mars

10:00 am

New data from Curiosity has confirmed that the winds of Mars have been the primary force shaping the red planet’s landscape for billions of years.

The new data suggests that Mount Sharp once filled Gale Crater, and it was the winds that eroded it away to create the impression that it is the crater’s central peak. Instead it appears that it is the crater’s original floor!

Below the fold is the video from the link showing a number of dust devils imaged by Curiosity.

This link provides a gif animation showing the surprisingly significant changes to the ripples in the sand dunes directly below Curiosity that take place in only one day. The changes are astonishing, and show that even though Mars’ atmosphere is far thinner than Earth’s, it is capable of moving things quickly across the Martian surface.
» Read more

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The oldest fossils ever?

7:35 pm

Scientists think they have found the oldest fossils ever in Canada.

Scientists say they have found the world’s oldest fossils, thought to have formed between 3.77bn and 4.28bn years ago. Comprised of tiny tubes and filaments made of an iron oxide known as haematite, the microfossils are believed to be the remains of bacteria that once thrived underwater around hydrothermal vents, relying on chemical reactions involving iron for their energy.

If correct, these fossils offer the oldest direct evidence for life on the planet. And that, the study’s authors say, offers insights into the origins of life on Earth. “If these rocks do indeed turn out to be 4.28 [bn years old] then we are talking about the origins of life developing very soon after the oceans formed 4.4bn years ago,” said Matthew Dodd, the first author of the research from University College, London.

This discovery reminds me of the Mars fossils discovered in the late 1990s. There were enormous uncertainties with that discovery, all of which eventually caused most scientists in the field to reject the result. The same thing could be the case here.

Still in Dallas. I hope to get caught up tomorrow.

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China considering multi-asteroid mission

7:16 pm

The competition heats up: China is considering an unmanned probe to visit three different asteroids, including Apophis.

According to details that have previously emerged, one proposal is for a launch via Long March 3B rocket to take place in early 2022, with rendezvous with Apophis a year later and spend 220 days in orbit.

Then the probe would depart Apophis for a flyby of 2002 EX11 in 2025, and finally landing on 1996 FG3 in 2027, where it would, in Ji’s words, “conduct in-situ sampling analysis on the surface”.

The proposal is only in the design stage, but it should definitely be taken seriously. China is committing more and more of its resources to its space program, as that program is giving that government a big payoff in international recognition.

Posted in the airport in Dallas, where I have to wait an extra three hours because American Airlines practically shut the door to my connecting flight in my face. Their flight from Belize was late, and then Customs and the TSA conspired to create giant lines for no reason. Even though I had a friend at the gate with whom we were in contact by text who could tell them I was only a minute away, they shut the door anyway.

I have avoided American for more than a decade because they did something as obnoxious to me before. I think it might be a decade before I fly them again.

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A solar system of exoEarths!

1:53 pm

Astronomers have discovered a nearby solar system of exoplanets, all approximately Earth-sized with at least three in the habitable.

Following these initial findings, the star was systematically monitored to find out whether it contained any other planets. The result of this follow-up exceeded all expectations: TRAPPIST-1 has at least seven planets, all of which are Earth-sized (to within 15%). The six nearest planets (b to g) orbit their star in 1.5 to 12 days (the period of the seventh planet remains to be determined), and are 20 to 90 times closer to their star than the distance from the Earth to the Sun. At such distances, the tidal forces exerted by the star are considerable, locking the planets into synchronous rotation, which means that they rotate about their axis exactly once in one orbit, thus always showing the same face to their star (just as the Moon does relative to the Earth).

The planets of TRAPPIST-1 have insolations, and therefore average temperatures, similar to Earth’s: the insolation of the innermost planet (b) is slightly higher than that of Mercury, while the outermost planets (g and h) have an insolation that is a little lower than that of Mars. The insolations of at least three of the planets (e, f and g) are compatible with the existence of liquid water on their surface for a wide range of atmospheric compositions, as is shown by numerical simulations of their climate. Due to their synchronous rotation, it cannot be excluded that the planets with the highest irradiation (b, c and d) may harbor liquid water in temperate regions with little or no sunlight.

More here. The star, a cool dwarf, is only 40 light years away.

Posted in the Belize City airport, as we wait for our pickup.

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Scientists propose new planet definition that reinstates Pluto

6:03 pm

Unhappy since 2006 with the definition of “planet” imposed by the International Astronomical Union (IAU) that demoted Pluto, planetary scientists, including New Horizons principal investigator Alan Stern, have now proposed a new definition that they think is more appropriate and would reinstate Pluto.

The scientists suggest planets should constitute as “round objects in space that are smaller than stars,” thus excluding white dwarfs, neutron stars, and black holes from the planetary status. “A planet is a sub-stellar mass body that has never undergone nuclear fusion and that has sufficient self-gravitation to assume a spheroidal shape adequately described by a triaxial ellipsoid regardless of its orbital parameters,” the proposal elaborates, noting that the Earth’s moon would constitute as a planet under the new definition.

Stern and his colleagues note that the IAU’s definition of a planet is too narrow and recognizes planets only as objects that orbit our sun and “requires zone clearing, which no planet in our solar system can satisfy since new small bodies are constantly injected into planet-crossing orbits.”

Make sense to me as well as a lot of people. The definition created in 2006 was never very satisfactory, and I know many planetary scientists who have never accepted it.

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Juno to remain in 53-day orbit

1:47 pm

The scientists and engineers running the Juno mission to Jupiter have decided to keep the spacecraft in its 53-day orbit for the rest of its mission rather than fire its engines to lower the orbit to its planned 14 days duration.

The original Juno flight plan envisioned the spacecraft looping around Jupiter twice in 53-day orbits, then reducing its orbital period to 14 days for the remainder of the mission. However, two helium check valves that are part of the plumbing for the spacecraft’s main engine did not operate as expected when the propulsion system was pressurized in October. Telemetry from the spacecraft indicated that it took several minutes for the valves to open, while it took only a few seconds during past main engine firings. “During a thorough review, we looked at multiple scenarios that would place Juno in a shorter-period orbit, but there was concern that another main engine burn could result in a less-than-desirable orbit,” said Rick Nybakken, Juno project manager at NASA’s Jet Propulsion Laboratory in Pasadena, California. “The bottom line is a burn represented a risk to completion of Juno’s science objectives.”

There are both pros and cons for using this longer orbit, detailed at the link, with.the most important being that doing nothing avoids losing the mission entirely.

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Dawn finds organics on Ceres

9:34 pm

The spacecraft Dawn has detected evidence of organic molecules in Ceres’ northern hemisphere.

The organic materials on Ceres are mainly located in an area covering approximately 400 square miles (about 1,000 square kilometers). The signature of organics is very clear on the floor of Ernutet Crater, on its southern rim and in an area just outside the crater to the southwest. Another large area with well-defined signatures is found across the northwest part of the crater rim and ejecta. There are other smaller organic-rich areas several miles (kilometers) west and east of the crater. Organics also were found in a very small area in Inamahari Crater, about 250 miles (400 kilometers) away from Ernutet.

This detection does not mean that Dawn has found life on Ceres. It means that the spacecraft has detected molecules that contain carbon, which is the chemical definition of organics. Nor is it unusual for asteroids to have carbon molecules. In fact, there is an entire asteroid class dubbed carbonaceous chondrites that are rich in carbon. In addition, the press release overplays this narrative by making it seem as if the discovery of organics in the solar system is rare and unusual. It is not. Molecules containing carbon have been found in many places, on Mars, on Venus, in asteroids, and elsewhere. All that is happened here is that the scientists have gained more information about the make-up Ceres itself. This is good, but it isn’t what is being sold by the press release.

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UAE proposes building Martian city within a century

12:13 pm

The competition heats up? The United Arab Emirates announced on Tuesday its plan to construct a city on Mars and have it completed by 2117, a hundred years from now.

On Tuesday, at the sidelines of the World Government Summit in Dubai, the UAE announced that it was planning to build the first city on Mars by 2117. According to CNBC, UAE engineers presented a concept city at the event about the size of Chicago for guests to explore.

In a statement, Sheikh Mohammed bin Rashid Al Maktoum, ruler of Dubai and vice president of the UAE, sounded confident about the project. “Human ambitions have no limits, and whoever looks into the scientific breakthroughs in the current century believes that human abilities can realize the most important human dream,” Maktoum said.

And despite the grandiose nature of the idea, the 100-year-plan does emphasize some practical steps. “The Mars 2117 Project is a long-term project,” Maktoum explained in the statement, adding that the first order of business would be making space travel appeal to young Emiratis, with special programs in space sciences being set up at universities in the UAE.

Maktoum is the guy that pushed to create the UAE’s space agency, and is leading its effort to fly an unmanned mission to Mars by 2020. It is very clear that his goal is to inspire his country and its youth so that they will aim high in future years. I wish him well, as this is a far better goal for an Islamic nation than sending out suicide bombers to kill innocent people.

I must add that I remain very skeptical about this particular plan. I fully expect us to finally get to Mars in the next century, but whether we will have the ability to build cities there in that time frame remains questionable.

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Maybe the Earth’s magnetic field is not weakening

3:31 pm

The uncertainty of science: New data using date-stamped jars covering the period from the 8th to the 2nd century BC suggest that the 8th century BC was a period when the Earth’s magnetic field was particularly strong, leading the scientists doing the research to conclude that the Earth’s magnetic field might not be weakening and that the recent field strength decline detected in the past two hundred years might simply be part of the field’s normal fluctuations.

This new data is certainly worthwhile, but the press release surely doesn’t reveal how the scientists were able to extrapolate future magnetic field strength from 8th century BC fluctuations. At a minimum, I would need to see a graph showing the measured field strength from the 8th century BC to the present time to see how today’s field strength compares with the past. Unfortunately, the press release does not provide this.

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Mars rover update: February 14, 2017

2:54 pm

Curiosity

Ireson Hill, Sol 1604

Dune fields

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

Taking a close look at rock

Since my last update in January, Curiosity done more or less what I predicted. It headed southwest through the dune area and then made a side trip to the small mesa there, dubbed Ireson Hill by the Curiosity science team and shown on the right. They then made an additional side trip past the hill to get a close look a the large sandy dune field beyond, also shown on the right. After getting some nice closeups as well as scooping up some sand for observation, they have now gone back to Ireson Hill to get another close look at the dark rocks that have rolled off the top of the hill and are now in reach at its base. The image on the left shows the arm positioned above one of those rocks.

The drill remains out of commission, with no word when they will try using it again. In addition, there had been a problem with the ChemCam laser that does spectroscopic analysis, but as of this week it is back in action, and is being used to analysis the small rock above.

Below is an overview of their route so far as well as my annotations on where I think they will be heading in the future.
» Read more

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A comet breaks apart

9:27 am

On February 12 members of the amateur astronomy organization Slooh actually viewed the break-up of Comet 73P/Schwassmann-Wachmann into two large fragments.

On the night of February 12th, Slooh members using the company’s telescopes in Chile were able to view the comet as it broke into two pieces. This seems to be the continuation of a process that was first witnessed in 1995, then again in 2006.

Slooh members were among the first to confirm that the nucleus of comet 73P/Schwassmann-Wachmann had split into at least two large pieces. “They immediately pointed Slooh’s telescopes to capture the event,” says Slooh Astronomer, Paul Cox. “Members will continue to monitor the comet live over the coming weeks – assuming the comet survives that long.”

They have created an animation from their images, but it appears that they only started taking images after the actual breakup, so the animation shows the two fragments, but not the moment they broke apart.

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Heart risks from secondhand smoke completely bogus

7:09 pm

The uncertainty of science: New more carefully done research now proves that secondhand smoke from smoking does almost nothing to increase the risk of heart disease.

In the early 2000s, as jurisdictions across the country fought over expanding smoking bans to bars and restaurants, anti-smoking advocates seized on the Helena study and related research showing that secondhand smoke exposure can affect coronary functions to promote fear of secondhand smoke. Groups across the country stated that “even half an hour of secondhand smoke exposure causes heart damage similar to that of habitual smokers.” Not to be outdone, the Association for Nonsmokers in Minnesota wrote in a press release that just 30 seconds of exposure could “make coronary artery function of non-smokers indistinguishable from smokers.” The message to nonsmokers was clear: The briefest exposure to secondhand smoke can kill you.

A decade later, comprehensive smoking bans have proliferated globally. And now that the evidence has had time to accumulate, it’s also become clear that the extravagant promises made by anti-smoking groups—that implementing bans would bring about extraordinary improvements in cardiac health—never materialized. Newer, better studies with much larger sample sizes have found little to no correlation between smoking bans and short-term incidence of heart attacks, and certainly nothing remotely close to the 60 percent reduction that was claimed in Helena. The updated science debunks the alarmist fantasies that were used to sell smoking bans to the public, allowing for a more sober analysis suggesting that current restrictions on smoking are extreme from a risk-reduction standpoint.

As almost always happens, the people pushing for the ban really weren’t that interested in protecting people’s health. They might have thought so, but in reality what they were really interested in was exerting their power over others, banning smoking and telling everyone else how to live their lives.

Read the whole article. It is very damning, and illustrates again why it is very important to not pass laws quickly based on some preliminary scientific results. Care must be taken, and patience is required. The science is never clear right from the beginning, especially on complex issues like climate and the health effects involving large numbers of people.

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NSF voids punishment of scientists who committed plagiarism and data fabrication

10:34 am

An inspector general report has found that the National Science Foundation has routinely cancelled or reduced the punishments of scientists who had committed either plagiarism or data fabrication, allowing them to continue to get grants and advise the government.

The inspector general for the National Science Foundation identified at least 23 instances of plagiarism in proposals, NSF-funded research, and agency publications in 2015 and 2016. It found at least eight instances of data manipulation and fabrication in those years. NSF officials disregarded recommended sanctions against some of the scientists and academics implicated in those findings. Though many were temporarily barred from receiving additional federal funding, nearly all will be eligible for taxpayer support and official roles in NSF-funded research in the future.

In one investigation that concluded in Nov. 2015, the IG found that an NSF-supported researcher had “knowingly plagiarized text into five NSF proposals.”

“These actions were a significant departure from the standards of the research community, and therefore constituted research misconduct,” according to a report on the investigation’s findings.

No wonder the public has become very skeptical of government science. Worse, by turning a blind eye to this bad behavior the National Science Foundation ends up giving a black eye to all science.

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NASA narrows to three the Mars rover landing sites in 2020

2:59 pm

Jezero Crater

Scientists have now narrowed to three the candidate landing sites for NASA’s 2020 Mars rover mission.

The three sites include Jezero crater, which was once home to an ancient Martian lake and which could preserve the remains of microbial life, if it ever existed on Mars. “You’ve got a large river bringing water and sediment into a very large lake, comparable to Lake Tahoe,” says Timothy Goudge, a planetary scientist at the University of Texas at Austin. Jezero scored highest on a community vote of scientists attending the workshop.

Other possible targets include Northeast Syrtis, where hot waters once circulated through the crust and could have supported life, and Columbia Hills, the area explored for years by NASA’s Spirit rover.

From the Nature article above as well as this Science article, it sounds like the Columbia Hills choice is unlikely. The Science article pushes Jezero crater, which had the most votes at the workshop and is shown in the image on the right.

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How Differential Gear works

6:02 pm

An evening pause: Though the first 1:50 of this very well done 1930s industrial is somewhat irrelevant and can be skipped, I think it is worth watching anyway. And the rest does a great job of explaining this mysterious piece of automobile equipment.

Hat tip Edward Thelen.

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An orbital change extends the life of India’s Mars orbiter

8:32 am

An orbital maneuver has allowed India’s Mars Orbiter Mission avoid an eight hour period with no sunlight — thus draining its batteries — so that the mission can be extended until 2020.

The on-board battery which was to take over had a life of just about 1.4 hours, while the eclipse was to last for 8 hours. The spacecraft’s future was bleak.

The scientists thought of a solution. On the night of January 17, a team of eight engineers at Indian Space Research Organisation’s Telemetry, Tracking and Command Network, Bengaluru, sent a time-delayed command to the Mars probe. The command set in motion firing of eight on-board thruster rockets. Each of them were fired for 431 seconds, pushing the Mars Orbiter Mission (MOM) space probe to a new orbit that completely avoids an eclipse up to September 2017. The shadowing in September is of a smaller duration, which the satellite’s batteries can handle. “Because of the crucial orbital change, the MOM now gets three additional years’ life. We are expecting it to transmit data till 2020,” Isro chairman A S Kiran Kumar told DH.

The mission’s science data is not as important as the experience it is giving Indian engineers in operating a planetary probe remotely from Earth. This success speaks well for the future of India’s space effort.

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New Curiosity data leaves scientists baffled about past evidence of water

2:37 pm

The uncertainty of science: Despite substantial evidence by Curiosity that Gale Crater once had running water and even lakes, the rover has also found no evidence that the atmosphere ever had enough carbon dioxide in its atmosphere to warm the climate enough to allow that water to flow as a liquid.

Mars scientists are wrestling with a problem. Ample evidence says ancient Mars was sometimes wet, with water flowing and pooling on the planet’s surface. Yet, the ancient sun was about one-third less warm and climate modelers struggle to produce scenarios that get the surface of Mars warm enough for keeping water unfrozen.

A leading theory is to have a thicker carbon-dioxide atmosphere forming a greenhouse-gas blanket, helping to warm the surface of ancient Mars. However, according to a new analysis of data from NASA’s Mars rover Curiosity, Mars had far too little carbon dioxide about 3.5 billion years ago to provide enough greenhouse-effect warming to thaw water ice.

The same Martian bedrock in which Curiosity found sediments from an ancient lake where microbes could have thrived is the source of the evidence adding to the quandary about how such a lake could have existed. Curiosity detected no carbonate minerals in the samples of the bedrock it analyzed. The new analysis concludes that the dearth of carbonates in that bedrock means Mars’ atmosphere when the lake existed — about 3.5 billion years ago — could not have held much carbon dioxide.

Does anyone but me see the faulty scientific reasoning here? Basically, these scientists appear to be assuming that the only global warming atmospheric molecule that exists is carbon dioxide. And because Mars has little carbonates in its surface, meaning it had little past CO2 in its atmosphere, there thus no way Mars’ atmosphere could have been warmed enough to allow water to flow as a liquid.

Balderdash! On Earth, the most important global warming component in the atmosphere is water, not carbon dioxide. Moreover, there are other atmospheric components, such as methane, that are also more important than CO2 in warming the climate. In fact, carbon dioxide as a trace gas in the atmosphere plays only a tiny global warming role. On Mars it is just as likely that other atmospheric components, such as water and methane, provided the necessary warming. To assume it has to be carbon dioxide suggests to me that these scientists have become so caught up with the human-caused global warming scare here on Earth that they have lost the ability to consider other possibilities on Mars.

Nonetheless, this remains the fundamental scientific mystery of Mars. We have found enormous evidence on Mars that water once flowed on its surface. We have also found no explanation so far that would explain how that was possible.

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The Sun turns

11:33 am

NOAA today posted its monthly update of the solar cycle, covering sunspot activity for January. As I do every month, I am posting it here with annotations to give it context.

January 2017 Solar Cycle graph

The graph above has been modified to show the predictions of the solar science community. 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.

Since my last solar cycle update, sunspot activity showed a slight increase in activity when compared to the previous month. Overall, however, the ramp down from solar maximum continues to underperform the predictions, and suggests that this solar maximum will not only be a very weak one, but a short one as well.

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.

Silso daily sunspot graph, January to February 2017

This pattern was very evident in January, as shown by the graph on the right and obtained from here. During the first two weeks of the month the Sun was blank. Then that inactive face rotated out of view. For the next two weeks or so the sunspot count went up, then began to drop as the active face began to rotate out of view to be replaced by the blank face last seen in early January.

This pattern of course is very fluid, as at any time the inactive face can become more active and the active face less so. Nonetheless, for short periods covering one to three months it helps to partly explain the up-and-down pattern of sunspot fluctuations during this time period when large portions of the Sun’s face are blank.

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At Jupiter reality imitates art

9:20 am

Jupiter's south pole, fourth flyby

NASA this week released images taken by Juno during its fourth close fly-by of Jupiter on February 2. The image highlighted by that press release focused on a wide lightly processed view of the south pole, different from the image above. As the release states,

Prior to the Feb. 2 flyby, the public was invited to vote for their favorite points of interest in the Jovian atmosphere for JunoCam to image. The point of interest captured here was titled “Jovian Antarctica” by a member of the public, in reference to Earth’s Antarctica.

The image above, cropped and reduced here, was more heavily processed by another member of the public, and shows more clearly the mad, chaotic storms at the south pole.

What instantly struck me when I saw this however was how much it reminded me of this piece of art, painted in 1889 in France by a man who was slowly going insane.

The Starry Night

Vincent Van Gogh never saw the storms on Jupiter, but his imagination conceived their existence in paint. Juno has now imaged them in reality.

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