Tag: science

OSIRIS-REx to search for Earth’s Trojan asteroids

4:57 pm

As it heads outward for a rendezvous with the asteroid Bennu, OSIRIS-REx will turn on its instruments for 12 days in February 2017 to hunt for the Trojan asteroids that likely orbit the Sun in the Earth’s orbit 60 degrees ahead and behind it.

Six planets in our solar system are known to harbor Trojan asteroids — Jupiter, Neptune, Mars, Venus, Uranus and Earth. Although more than 6,000 Trojan asteroids are known to be orbiting along with Jupiter, scientists have discovered only one Earth Trojan to date: 2010 TK7, found by NASA’s NEOWISE project in 2010. Scientists predict that there should be more Trojans orbiting Earth, but these asteroids are difficult to detect because they appear close to the sun from Earth’s point of view. In mid-February 2017, however, the OSIRIS-REx spacecraft will be ideally positioned to undertake a survey of the stable point in front of Earth.

Over 12 days, the OSIRIS-REx Earth-Trojan asteroid search will employ the spacecraft’s MapCam imager to methodically scan the space where Earth Trojans are expected to exist. MapCam is part of the OSIRIS-REx Camera Suite, or OCAMS, which was designed and built by researchers at the UA’s Lunar and Planetary Laboratory.

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Did a giant black hole eat a star?

10:45 am

New data now suggests that what astronomers had thought was the brightest supernova ever detect might have instead been the ripping apart of a star as it passed too close to a supermassive black hole.

In this scenario, the extreme gravitational forces of a supermassive black hole, located in the centre of the host galaxy, ripped apart a Sun-like star that wandered too close — a so-called tidal disruption event, something so far only observed about 10 times. In the process, the star was “spaghettified” and shocks in the colliding debris as well as heat generated in accretion led to a burst of light. This gave the event the appearance of a very bright supernova explosion, even though the star would not have become a supernova on its own as it did not have enough mass. The team based their new conclusions on observations from a selection of telescopes, both on the ground and in space. Among them was the NASA/ESA Hubble Space Telescope, the Very Large Telescope at ESO’s Paranal Observatory and the New Technology Telescope at ESO’s La Silla Observatory

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Curiosity cleared to move but not drill

9:34 am

Engineers have cleared Curiosity to move once again, but have not yet cleared the rover to use its balky drill.

This morning we received downlink that indicated operation of the drill feed using standard commands. This is great news, and the anomaly response team has cleared the rover for use of the arm and driving (but not yet drilling).

It is not known when they will drill again, but the news suggests that they will do so eventually, once they get a full understanding of what prevented normal operations this last time. For moment, at least, they no longer have a need to keep the rover motionless so they could assess the situation.

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First dinosaur tail found, preserved in amber

8:22 am

Paleontologists have discovered the first completely preserved dinosaur tail, feathers and all, preserved in amber.

Inside the lump of resin is a 1.4-inch appendage covered in delicate feathers, described as chestnut brown with a pale or white underside. CT scans and microscopic analysis of the sample revealed eight vertebrae from the middle or end of a long, thin tail that may have been originally made up of more than 25 vertebrae. Based on the structure of the tail, researchers believe it belongs to a juvenile coelurosaur, part of a group of theropod dinosaurs that includes everything from tyrannosaurs to modern birds.

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Juno’s upcoming December 11 Jupiter flyby

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The Juno science team prepares for the next close flyby of Jupiter on December 11.

At the time of closest approach (called perijove), Juno will be about 2,580 miles (4,150 kilometers) above the gas giant’s roiling cloud tops and traveling at a speed of about 129,000 mph (57.8 kilometers per second) relative to the planet. Seven of Juno’s eight science instruments will be energized and collecting data during the flyby. “This will be the first time we are planning to operate the full Juno capability to investigate Jupiter’s interior structure via its gravity field,” said Scott Bolton, principal investigator of Juno from the Southwest Research Institute in San Antonio. “We are looking forward to what Jupiter’s gravity may reveal about the gas giant’s past and its future.”

Mission managers have decided not to collect data with the Jovian Infrared Auroral Mapper (JIRAM) instrument during the December flyby, to allow the team to complete an update to the spacecraft software that processes JIRAM’s science data. A software patch allowing JIRAM’s operation is expected to be available prior to the next perijove pass (PJ4) on Feb. 2, 2017.

It increasingly appears they do not want to risk firing the spacecraft’s main engine to shorten the 53 day orbit to 14 days because of a fear that the burn could fail catastrophically. This means that Juno’s mission will be extended significantly because it will take longer to gather data with such a long orbit.

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Jupiter’s chaotic storms

9:32 am

Jupiter's storms, as seen by Juno after processing

Cool image time! The image on the right shows what anyone can do if they want to play with images that have been taken by the Juno spacecraft. On top is the raw Juno image of a storm on Jupiter. On the bottom is that same storm after significant processing by an ordinary citizen. A larger version can be seen here.

While the Juno science team’s policy of making all their raw images available to the public is routine for a NASA mission, they are doing something a bit different by allowing the public to play with the images and then upload them on a Juno website for everyone to see. While some of the subsequent images have been a little silly, the image on the right illustrates how this policy can help scientists (and the public) better study the atmosphere on Jupiter. The processing has brought out all the storm’s swirls and twirls, and shown clearly how chaotic the storms are in Jupiter’s high latitudes.

The scientists don’t have the resources or the time to do this kind of processing on every image, or even every piece of every image. Allowing the public to do it will increase the variety of results and make it more likely for everyone to gain some understanding of what is going on in the gas giant’s atmosphere. Or not, but then that’s okay, as a realization that we don’t understand something is the first step towards wisdom and real knowledge.

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Mars rover update: December 8, 2016

4:23 pm

Curiosity

Mars' dusty sky

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

Since my last rover update on November 14th, Curiosity moved relatively little. They drove a short distance to the southeast to a point where they wanted to drill, but have not moved from this location for the past two weeks because of drill issues.

While the engineers study the drill problem, which requires them to not move either the rover or the drill arm, the scientists have still used Curiosity to take images of the dust in the sky, to take hourly images of the dust on the ground (to see how it is changed by the wind), and to take images of nearby interesting nearby features (below the fold).
» Read more

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Two new studies say different things about Greenland’s icecap history

9:00 am

The uncertainty of science: Two new studies of Greenland’s icecap suggest completely opposite histories, with one saying that Greenland was ice free at least once in the past 2.6 million years, with the other saying that the icecap covered Greenland continuously for the past 7.5 million years.

Evidence buried in Greenland’s bedrock shows the island’s massive ice sheet melted nearly completely at least once in the last 2.6 million years. This suggests that Greenland’s ice may be less stable than previously believed. “Our study puts Greenland back on the endangered ice-sheet map,” says Joerg Schaefer, a palaeoclimatologist at the Lamont-Doherty Earth Observatory in Palisades, New York, and co-author of a paper published on 7 December in Nature.

A second paper in the same issue paints a slightly different view of the ice sheet’s past stability. A group led by Paul Bierman, a geomorphologist at the University of Vermont in Burlington, found that ice covered eastern Greenland for all of the past 7.5 million years. Experts say the two papers do not necessarily contradict one another: at times, nearly all of Greenland’s ice could have melted (as seen by Schaefer’s team) while a frosty cap remained in the eastern highlands (as seen by Bierman’s group).

If all of Greenland’s ice melted, it would raise sea levels by seven metres. Models suggest that Greenland could become ice-free as soon as 2,500 years from now, depending on the concentration of greenhouse gases in the atmosphere. [emphasis mine]

This story is a perfect example of how the passionate belief in a theory (that global warming is happening, is a threat, and will melt the icecaps) can warp a scientist’s thinking. Both studies used a single drilled ice core, with the first from Greenland’s central region and the second from Greenland’s eastern region. Thus, there is no reason to say that the entire Greenland icecap had melted, as noted in the highlighted text that describes the first study. What the data merely suggests is that these two regions might have had different histories.

Instead, the article, in its effort to confirm the possibility that Greenland’s icecap could melt entirely and thus pose a threat of a big sea level rise, ignores this simple detail and struggles to justify the concept that the entire cap certainly melted in the past, even though one study suggests otherwise. This causes everyone to misunderstand the results, and draw conclusions that are uncalled for, based on the available data.

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Design flaw in India’s Mars Orbiter

8:52 pm

According to American researchers, a fundamental design flaw in the primary scientific instrument on India’s Mangalyaan Mars orbiter prevents it from carrying out its mission of measuring the methane in the Martian atmosphere.

“They did not design this properly for the detection of methane on Mars,” Michael Mumma, senior scientist at NASA’s Goddard Space Flight Center, told Seeker. In 2003, Mumma led a team that made the first definitive measurements of methane on Mars using an infrared telescope in Hawaii. The methane, which appeared in plumes over specific regions of Mars, reached a maximum density of about 60 parts per billion. “The (MOM) instrument is beautifully engineered, but not for the methane task. It has other value, but unfortunately they will not be able to provide measurements of methane at the levels needed to sample even the plumes we saw,” Mumma said.

They are re-purposing the instrument to measure the reflected sunlight coming off the Martian surface, useful data to be sure but hardly worth an entire space mission.

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The weird south pole of Mars

5:45 pm

Mars' south pole region

Cool image time (literally)! The photo above, cropped slightly to show here, was taken by Mars Reconnaissance Orbit (MRO) in August 2016 and was released today as part of the monthly release of captioned images. And though it looks like a fractal computer-generated animation still, it is instead real, showing the strange and quite alien terrain that routinely forms at the carbon dioxide ice cap there.

The polar cap is made from carbon dioxide (dry ice), which does not occur naturally on the Earth. The circular pits are holes in this dry ice layer that expand by a few meters each Martian year. New dry ice is constantly being added to this landscape by freezing directly out of the carbon dioxide atmosphere or falling as snow. Freezing out the atmosphere like this limits how cold the surface can get to the frost point at -130 degrees Celsius (-200 F). Nowhere on Mars can ever get any colder this, making this this coolest landscape on Earth and Mars combined!

This region is about 4 degrees north of the south pole itself.

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ExoMars’ Trace Gas Orbiter images Phobos

9:08 pm

As part of its checkout, Europe’s ExoMars’ Trace Gas Orbiter has taken test images of the Martian moon Phobos.

The camera imaged the moon on 26 November from a distance of 7700 km, during the closest part of the spacecraft’s orbit around Mars. TGO’s elliptical orbit currently takes it to within 230–310 km of the surface at its closest point and around 98 000 km at its furthest every 4.2 days. A colour composite has been created from several individual images taken through several filters. The camera’s filters are optimised to reveal differences in mineralogical composition, seen as ‘bluer’ or ‘redder’ colours in the processed image. An anaglyph created from a stereo pair of images captured is also presented, and can be viewed using red–blue 3D glasses.

The images were done to test the spacecraft’s operation, and have apparently shown that it is functioning well.

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First images from Cassini’s first Saturn ring flyby

9:01 pm

Saturn's polar vortex

Cool image time! And this is only the start. The Cassini science team has released the first images taken by Cassini during its first of 42 close flybys of the rings of Saturn. The image on the right, cropped from the full image, shows Saturn’s north polar vortex. The storm at the polar really does look like a whirlpool that is descending down into the gas giant’s depth.

I must emphasize that photography was not the focus of this first flyby. These images were taken the two days before the flyby on December 4. Later flybys are going to produce far better images, as they will be taking pictures throughout.

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Sunspot activity continues to drop

3:21 pm

NOAA yesterday posted its monthly update of the solar cycle, covering sunspot activity for November. Below is my monthly annotated version of that update.

November 2016 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.

In November sunspot activity dropped again, to the second lowest point seen since 2010. Essentially, activity today is about where it was in 2010 when the solar minimum was finally ending. Now, the solar maximum is ending and we are beginning the next solar minimum.

Throughout the entire just completed solar maximum, the Sun continuously under-performed all predictions. Even now, despite following almost precisely the prediction of the 2007 low prediction during 2014 and 2015, in 2016 the ramp down has begun to slip below that prediction. The trend continues to suggest the arrival of solar minimum will be early, possibly as early as sometime late next year.

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Drill issues at Curiosity

9:05 am

The recent failure by Curiosity to drill has caused engineers to stop the rover in its tracks while they analyze the cause of the problem.

The rover team learned Dec. 1 that Curiosity did not complete the commands for drilling. The rover detected a fault in an early step in which the “drill feed” mechanism did not extend the drill to touch the rock target with the bit. “We are in the process of defining a set of diagnostic tests to carefully assess the drill feed mechanism. We are using our test rover here on Earth to try out these tests before we run them on Mars,” Curiosity Deputy Project Manager Steven Lee, at NASA’s Jet Propulsion Laboratory in Pasadena, California, said Monday. “To be cautious, until we run the tests on Curiosity, we want to restrict any dynamic changes that could affect the diagnosis. That means not moving the arm and not driving, which could shake it.”

Two among the set of possible causes being assessed are that a brake on the drill feed mechanism did not disengage fully or that an electronic encoder for the mechanism’s motor did not function as expected. Lee said that workarounds may exist for both of those scenarios, but the first step is to identify why the motor did not operate properly last week.

Though they do not say so, the problem is almost certainly related to a fundamental design flaw in the drill’s design that causes intermittent short-circuits when they use it, and has the possibility of shorting out the entire rover if they are not careful.

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Cassini makes its first close ring flyby of Saturn

2:46 pm

Cassini has begun its last year at Saturn, making its first close fly-by of the gas giant’s rings yesterday.

Cassini’s imaging cameras obtained views of Saturn about two days before crossing through the ring plane, but not near the time of closest approach. The focus of this first close pass was the engine maneuver and observations by Cassini’s other science instruments. Future dives past the rings will feature some of the mission’s best views of the outer regions of the rings and small, nearby moons.

Each of Cassini’s orbits for the remainder of the mission will last one week. The next pass by the rings’ outer edges is planned for Dec. 11. The ring-grazing orbits — 20 in all — will continue until April 22, when the last close flyby of Saturn’s moon Titan will reshape Cassini’s flight path. With that encounter, Cassini will leap over the rings, making the first of 22 plunges through the 1,500-mile-wide (2,400-kilometer) gap between Saturn and its innermost ring on April 26.

On Sept. 15, the mission will conclude with a final plunge into Saturn’s atmosphere. During the plunge, Cassini will transmit data on the atmosphere’s composition until its signal is lost.

Now for a bit of reality: When Cassini’s mission ends on September 15, 2017, it will likely be a minimum of 20 years before another spacecraft returns.

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The beginning of Cassini’s final year at Saturn

6:06 pm

Link here. The article does a nice job of outlining, with videos, what will happen as the spacecraft makes multiple dives inside rings.

Cassini’s final acts, which will play out over the next year. That pass placed Cassini in a high-inclination orbit tilted 60° relative to the ring plane. Cassini will perform 20 passes just 620 miles (1000 kilometers) outside the F ring of Saturn in a phase known as the Ring-Grazing Orbits, which runs from late November 2016 through April 2017.

Cassini already reached apoapse, or its farthest point from Saturn, on Wednesday, November 30th. The first ring crossing is coming right up this weekend on Sunday, December 4th, at 7:09 a.m. EST / 13:09 UT. During the first periapse pass on Sunday, Cassini will also burn its main engine for the 183rd and final time for the mission. All later fine course corrections will be made using thrusters only.

Things get even more interesting after April, when the series of Grand Finale Orbits will begin, taking the spacecraft through the 1240-mile-wide (2000-kilometer-wide) gap between the planet’s cloud tops and rings for 22 final orbits. The Grand Finale Orbits start with the spacecraft’s 126th and final pass near Titan, which will set the spacecraft up for much tighter final orbits.

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ESA approves ExoMars 2020 funding

5:58 pm

Despite the failure of the Schiaparelli lander on ExoMars 2016, the European Space Agency today approved funds to build and fly the ExoMars 2020 rover mission.

At a meeting of European government ministers in Lucerne, Switzerland, on 1 and 2 December, ESA member states agreed to provide an extra €339 million for ExoMars 2020. ESA also announced that it will find a further €97 million by moving funds internally. Speaking at a press briefing after the meeting, ESA director-general Jan Wörner said this would be done “without detriment” to ESA’s wider science budget.

But not all projects were so fortunate. Member states did not commit the €250 million needed to fund a plan for ESA to participate in a mission to deflect the moon of an asteroid, although they left door open to future, similar projects.

I am not at present sure how they are going to divide up the work between Europe and Russia. Earlier it was my understanding that Russia would provide the roving technology, but right now I am very unsure about this.

One side note: At this same meeting ESA committed to sticking with ISS through 2024.

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The science lobby looks at Trump’s pick for Health Secretary

10:11 am

Link here. The Nature article clearly takes a partisan and opposition view of Trump’s pick, Congressman Tom Price (R-Georgia). Nonetheless, it does give good insight into Price himself. I especially like this quote, used by Nature to imply that Price is somehow hostile to science:

But Price’s stance on biomedical research issues is harder to parse. He has taken few public positions on science, but has consistently pushed to cut overall federal spending. Last year, he voted against a bill that would overhaul FDA regulations and provide US$8.75 billion in mandatory funding to the NIH over five years.

Price also opposes President Barack Obama’s proposed $755-million Cancer Moonshot, which seeks to double the pace of cancer research over the next decade. “We’re all in favour of increasing funding for cancer research,” Price told STAT News in January. “The problem that the administration has is that they always want to add funding on, they never want to decrease funding somewhere else. That’s what needs to happen.” [emphasis mine]

There was once a time where Price’s approach would have been considered plain common sense. In today’s mad leftwing world however the idea that resources are not unlimited and that people have to make careful choices is considered evil and anti-science.

Expect these kinds of attacks to continue nonstop throughout the entire Trump administration, especially if that administration and Congress continue to push for a bit of restraint on budget issues. This is what happened during Reagan’s first term in the 1980s. The result was that eventually Reagan was never able to trim costs or eliminate any federal agencies, as the attacks caused many of his more radical cabinet picks to resign and the Republicans in Congress to eventually back down.

Today, however, things are different in one major way. Then, there was no alternative to the liberal press. Today, there are such alternatives. Moreover, the bias of the liberal press today is much more evident. Many more people recognize it, and do not take their howls of indignation as seriously. If Trump and the Republicans have some courage and do not back down, they can win this battle. All it will take is some courage. We shall see if they have it.

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Dispute in ESA over Schiaparelli failure

8:54 am

Prior to the release of ESA’s preliminary report on the failure of Schiaparelli, the Italian space agency had claimed the problem was caused by the failure of a Romanian subcontractor to do sufficient simulations and testing.

ESA released the preliminary conclusions after the Italian Space Agency had accused that the decisive tests for the Sciaparelli lander simulations had been entrusted to an organization “which hadn’t enough expertize”. It’s about Arca Space Romanian company, based in Las Cruces, USA, as La Repubblica reported.

In retort, the Arca Space Corporation manager, Dumitru Popescu warned the Italian space agency to be more careful, as they don’t have proves to support their accusations. “They could pay the price. We are at ease that we did all we could do: to run a specific test we should have flown very closely to the Russian base in Sevastopol. Russia has just annexed Crimea and we risked generating a conflict between the Russian Federation and NATO,” the Romanian manager argued.

There is something fishy here, but I’m not sure what. That they didn’t do a test because they feared instigating an international incident with Russia does not seem right. In fact, this whole story suggests that the very management structure of ESA, designed to spread work to as many of its partner nations as possible, is the fundamental source of the problem.

Hat tip reader Local Fluff.

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Drilling for the oldest ice

8:45 am

Using new drill technology scientists are now searching for the best place in Antarctica to obtain the oldest ice core ever drilled.

More than a decade ago, the European Project for Ice Coring in Antarctica (EPICA) drilled the oldest existing core, which contains 800,000-year-old ice, from an ice dome in East Antarctica known as Dome C. The core reaches only as far back as the latter part of the Pleistocene epoch, when Earth began cycling between warm and cold periods every 100,000 years. Before 1 million years ago, the cycle occurred every 40,000 years (L. E. Lisiecki and M. E. Raymo Paleoceanography 20, PA1003; 2005), so scientists want an ice core that is twice as old as EPICA to better understand this transition.

Digging such a core would cost about US$50 million and take several years, so researchers want to be sure that the location is optimal — with ice that is sufficiently deep but not melted at the bottom by geothermal activity. “It’s absolutely crucial to thoroughly investigate all options,” says Eisen. Enter a new breed of drill, designed to do fast, cheap reconnaissance instead of extracting a single, intact ice core, as previous deep drills have done.

One promising location, ‘little Dome C’, lies just 40 kilometres away from the EPICA site — and is where the £500,000 (US$620,000) Rapid Access Isotope Drill (RAID) will start boring this month, led by climate scientist Robert Mulvaney of the British Antarctic Survey in Cambridge, UK. A narrow drill, RAID will excavate to 600 metres in about 7 days — compared with 5 years for a 3.4-kilometre core such as EPICA’s. And rather than extract a core, RAID will measure the ice’s temperature and collect chips of ice. Scientists will then comb these for clues from isotopes as to the age and temperature of the ice at the bottom of the sheet.

There is competition here as well. Another more conventional drill operation, run by Chinese scientists, has already been drilling for several years and might actually obtain a core sample 1.5 million years old first.

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ExoMars’ Trace Gas Orbiter takes first pictures

8:30 am

The European Trace Gas Orbiter (TGO), part of the ExoMars 2016 mission, has successfully transmitted its first images back to Earth.

I have posted a video they have assembled of the first images below the fold. It is quite spectacular. As for TGO’s future misssion:

In the next months, the team will be starting preparations for the prime mission. “The test was very successful but we have identified a couple of things that need to be improved in the onboard software and in the ground post-processing», says Thomas. “It’s an incredibly exciting time.” Eventually, TGO will use “aerobraking” (skimming into the atmosphere) to slow the spacecraft down and enter a roughly circular orbit 400 km above this surface. This process will start in March 2017 and take around 9-12 months. The primary science phase will start around the end of 2017. CaSSIS will then enter nominal operations acquiring 12-20 high resolution stereo and colour images of selected targets per day.

» Read more

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SpaceX wins NASA satellite launch contract

6:28 pm

The competition heats up: NASA has awarded SpaceX the contract to launch its Earth science satellite, Surface Water and Ocean Topography (SWOT).

This sentence from the press release is puzzling:

The total cost for NASA to launch SWOT is approximately $112 million, which includes the launch service; spacecraft processing; payload integration; and tracking, data and telemetry support.

Since SpaceX touts a launch price for its Falcon 9 rocket as $62 million, I wonder why this launch will cost NASA almost twice as much. Was there so little competition in the bidding that SpaceX could bid higher and thus get more money? Or is NASA so disinterested in saving money that it left itself open to overpaying for something that everyone else gets for far else?

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Ceres’ cratered surface

10:27 am

Ceres' crated surface

Cool image time! The picture on the right, reduced to show here, was taken on October 17 and was the tenth image taken by Dawn in its new extended mission in orbit around Ceres.

This image of the limb of dwarf planet Ceres shows a section of the northern hemisphere. A shadowy portion of Occator Crater can be seen at the lower right — its bright “spot” areas are outside of the frame of view. Part of Kaikara Crater (45 miles, 72 kilometers in diameter) is visible at top left.

The image was taken from 920 miles away and has a resolution of about 460 feet per pixel.

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Drilling at the Chicxulub impact site has unveiled the crater’s shape

10:19 am

The new rock core drilled at the crater impact site that is thought to have help cause the extinction of the dinosaurs 65 million years ago has helped reveal the crater’s formation and shape, including the existence of an inner ring of mountains which scientists call a peak-ring.

After a decade of planning, the project penetrated 1,335 metres into the sea floor off the coast of Progreso, Mexico, in April and May. Drillers hit the first peak-ring rocks at a depth of 618 metres, and a pinkish granite at 748 metres. Geologists know that the granite must have come from relatively deep in the crust — perhaps 8–10 kilometres down — because it contains big crystals. The size of these crystals suggests that they formed by the slow cooling of deep, molten rock; in contrast, rapid cooling at shallow depth tends to form small crystals. Finding the granite relatively high in the drill core means that something must have lifted it up and then thrown down it on top of other rocks.

That rules out one idea of how craters form, in which the pulverized rock stays mostly in place like hot soup in a bowl. Instead, the core confirms the ‘dynamic collapse’ model of cosmic impacts, in which the asteroid punches a deep hole in the crust, causing the rock to flow like a liquid and spurt skyward. That rock then falls back to Earth, splattering around in a peak ring.

To put it another way, the impact moved the earth like a pebble dropped into a pond of water, causing at least two big circular ripples that flowed just like water but then quickly froze in place to form the two concentric peak-ring mountain ranges.

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Scientists puzzle over possible connection between a fast radio burst and a gamma ray burst

9:31 am

The uncertainty of science: In trying to explain the relatively new mystery of fast radio bursts (FRB), of which only about 20 have been detected and of which very little is known, scientists are intrigued by a gamma ray burst (GRB) that apparently occurred at the same time and place of one FRB.

Seeing the FRB event in a different wavelength would normally help astronomers better understand the FRB The problem is that this particular GRB only makes the mystery of FRBs more baffling.

One puzzle is that the two signals portray different pictures of the underlying source, which seems to be as much as 10 billion light years (3.2 gigaparsecs) away. Whereas the radio burst lasted just a few milliseconds, the γ-ray signal lasted between two and six minutes, and it released much more energy in total than the radio burst. “We’ve pumped up the energy budget more than a billion times,” says study co-author Derek Fox, an astrophysicist at Penn State.

This has big implications for the FRB’s origin. One leading theory suggests that FRBs are flares from distant magnetars — neutron stars with enormous magnetic fields that could generate short, energetic blasts of energy, and do so repeatedly, as at least one FRB is known to do. Although magnetars are thought to produce γ-rays, they would not emit such high energy and over such a long time, says Fox. “This is a severe challenge for magnetar models,” he says.

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New conclusions about Pluto from New Horizons data

1:00 am

Based on New Horizons data scientists have proposed that Pluto’s equatorial tilt has been shifted because of a seasonal pile-up of nitrogen that literally causes the planet to tip over.

Over the course of a Pluto year, nitrogen and other exotic gases condense on the permanently shadowed regions, and eventually, as Pluto goes around the sun, those frozen gases heat up, become gaseous again and re-condense on the other side of the planet, resulting in seasonal “snowfall” on Sputnik Planitia. “Each time Pluto goes around the sun, a bit of nitrogen accumulates in the heart,” Keane said. “And once enough ice has piled up, maybe a hundred meters thick, it starts to overwhelm the planet’s shape, which dictates the planet’s orientation. And if you have an excess of mass in one spot on the planet, it wants to go to the equator. Eventually, over millions of years, it will drag the whole planet over.”

The theory also requires there to be a subsurface ocean as well.

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TMT legal case in Hawaii gets messier

7:02 pm

The permit process in Hawaii for the Thirty Meter Telescope has gotten far messier, with the telescope’s opponents appealing to the state’s Supreme Court, complaining about witness procedures and the lawyers who are working for the state, while the land board running the procedures has asked the court to dismiss this appeal.

Essentially, the opponents are using every trick in the book to delay the permit process, and it appears that the law in Hawaii, including one just passed in August, is designed to aid them in this tactic.

TMT will not be built in Hawaii.The consortium that is building it needs a decision by early next year at the latest. They ain’t gonna get it. The luddites going to win, and Hawaii will be far poorer because of it.

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The Fact and Fiction of the NASA EmDrive Paper Leak

9:00 am

A NASA paper outlining work that appears to substantiate the EmDrive concept that involves the production of a thrust in a way that violates the laws of physics was leaked last week, and this story tries to figure out what has been learned.

To me, the key is this paragraph:

In essence, the NASA EmDrive in the paper consists of a closed copper cone, the inside of which is being bombarded with microwaves. To test the EmDrive, the researchers powered it with 40, 60, and 80 watts and found that it generated up to 58, 128, and 119 micronewtons of thrust, respectively. Given that this “anomaly” was still observed by White and his colleagues after accounting for error, this suggests that the results of the experiment show an EmDrive is indeed possible.

Based on these results, the researchers estimated that their contraption would be capable of generating approximately 1.2 millinewtons of thrust per kilowatt were they to scale up the power input. To put this in perspective, the Hall thruster—one of the most powerful in development and powered by ejecting plasma—generates about 60 millinewtons of thrust per kilowatt. [emphasis mine]

Interestingly , the article did not comment on how little thrust this EmDrive test produced. This tiny amount, however, to me suggests strongly that what they are measuring is some outside force acting on the drive that they have missed that would invalidate all the theories listed in the article. And even if the thrust drive does prove a new component of fundamental physics, as suggested in the article, the system simply doesn’t appear to produce enough thrust to make it practical.

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