Tag: science

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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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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