Tag: science

Japan’s Venus probe zeros in on Dec 7 arrival

9:53 pm

A Japanese Venus research spacecraft, dubbed Akatsuki, has completed all its preliminary course corrections and is ready for a December 7 orbital insertion attempt, the second since the spacecraft’s main engine failed during the first attempt in 2010.

The space probe accomplished its last targeting maneuver Oct. 11 to aim for its Dec. 7 arrival at Venus, and all systems are go for the encounter, said Takeshi Imamura, Akatsuki’s project scientist at JAXA’s Institute of Space and Astronautical Science. Imamura said the Akatsuki spacecraft, named for the Japanese word for dawn, will zoom 541 kilometers, or 336 miles, above Venus for a 20-minute insertion burn using the probe’s secondary attitude control thrusters. Japanese ground controllers have programmed the probe to use the backup rocket jets after a faulty valve knocked out Akatsuki’s main engine during its first attempt to enter orbit around Venus in December 2010.

Four of the eight attitude control thrusters aboard Akatsuki will fire for 20 minutes and 33 seconds to slow the spacecraft down enough for Venus’ gravity to pull it into an egg-shaped orbit that skims above the planet’s cloud tops on the low end and ranges several hundred thousand miles in altitude at peak altitude. The reaction control thrusters, originally designed to help point the spacecraft, were not rated for such a hefty propulsive maneuver.

To make this second chance possible, they have spent the last five years improvising. First they dumped the fuel from the now-useless main engine to make the spacecraft lighter so that the attitude control thrusters could handle the maneuvers. Then they used those thrusters repeatedly to adjust the course to bring Akatsuki back to Venus after it zipped past in 2010.

If they succeed in getting it in a useful orbit on December 7, it will be real triumph for these Japanese engineers.

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The first image of a newly formed exoplanet

9:45 pm

Astronomers have captured the first image, using ground-based telescopes, of an exoplanet in the process of forming.

The star is 450 light years away, and the image is really a combined image using data taken by two different telescopes, one in infrared light and the other gathering visible light spectroscopy. So, this really isn’t a photograph like you’d take with your camera, but a re-creation. Nonetheless it provides us a first look at the star and the new planet forming in orbit around it.

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Why the English language is odd

10:39 pm

Link here.

The writer outlines the history of English and how the many different languages that contributed to it caused it to be so different from most other languages. Some of the oddities he notes are quite fascinating because we English-speakers take them so much for granted. He only hints, however, at what is probably the English language’s greatest gift — its gigantic vocabulary resulting from its remarkable ability to absorb new words — which probably comes from that same polyglot history.

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Curiosity heads for the dunes

7:10 pm

Bagnold Dunes

The Curiosity science team has decided to send the rover towards some large active dunes, visible in its journey ahead up Mt. Sharp.

On its way to higher layers of the mountain where it is investigating how Mars’ environment changed billions of years ago, NASA’s Curiosity Mars rover will take advantage of a chance to study some modern Martian activity at mobile sand dunes.

In the next few days, the rover will get its first close-up look at these dark dunes, called the “Bagnold Dunes,” which skirt the northwestern flank of Mount Sharp. No Mars rover has previously visited a sand dune, as opposed to smaller sand ripples or drifts. One dune Curiosity will investigate is as tall as a two-story building and as broad as a football field. The Bagnold Dunes are active: Images from orbit indicate some of them are migrating as much as about 3 feet (1 meter) per Earth year. No active dunes have been visited anywhere in the solar system besides Earth.

In the image on the right the target dune is in the center beyond the dark ridge line in the foreground. It looks kind of like a pointed mesa. the dark sandy area on the center right just below the dark ridge line in the center of the image. (Newer images released today gave me a more correct idea of the dunes as shown in this image.) Click here to see the full image. The rover is presently about 200 yards from the first dune, and should reach it in the next few days.

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Enceladus rises over Dione

10:13 am

Enceladus rising behind Dione

Cool image time! The image on the right was taken by Cassini in September 2015, and shows two Saturn moons, bright Enceladus partly blocked by darker and nearer Dione.

Although Dione (near) and Enceladus (far) are composed of nearly the same materials, Enceladus has a considerably higher reflectivity than Dione. As a result, it appears brighter against the dark night sky.

The surface of Enceladus (313 miles or 504 kilometers across) endures a constant rain of ice grains from its south polar jets. As a result, its surface is more like fresh, bright, snow than Dione’s (698 miles or 1123 kilometers across) older, weathered surface. As clean, fresh surfaces are left exposed in space, they slowly gather dust and radiation damage and darken in a process known as “space weathering.”

The image doesn’t contain any earth-shattering discoveries. It is simply beautiful. And in these dark times, seeing beauty is sometimes the most important thing one can do.

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Mysterious piece of space junk burns up over Indian Ocean

9:05 am

Though scientists have not yet identified it, the piece of space junk discovered last month in an unusual orbit with a predictable moment of decay has burned up over the Indian Ocean,

Estimated to measure 1–2 metres across, WT1190F had circled the Earth–Moon system since at least 2009, says independent astronomy-software developer Bill Gray, who has been working with NASA to track the debris. It most likely came off a recent lunar spacecraft, but it is not out of the question that it could have dated to the Apollo era.

In at least one case, scientists were able to image the object as it burned up. The data from this will allow them to determine its chemical composition, which in turn might help them identify it.

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Astronomers measure 5,400 mph winds on exoplanet

8:55 am

Category 5! Astronomers have for the first time measured wind speeds on an exoplanet and they are a doozy!

Discovered on the exoplanet HD 189733b, the Warwick researchers measured the velocities on the two sides of HD 189733b and found a strong wind moving at over 5400 mph blowing from its dayside to its night side. Mr Louden explains: “HD 189733b’s velocity was measured using high resolution spectroscopy of the sodium absorption featured in its atmosphere. As parts of HD 189733b’s atmosphere move towards or away from the Earth the Doppler effect changes the wavelength of this feature, which allows the velocity to be measured.”.

This exoplanet was one of the first discovered by Kepler, which means its orbit transits its sun. In this case it does so every 2.2 days, and astronomers have taken advantage of these frequent transits to study the planet’s atmosphere as the star’s light travels through it. The result is that HD 187733b is probably one of the most studied exoplanets.

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Decline to solar minimum continues

11:26 am

It’s that time again buckos! On Monday NOAA posted its monthly update of the solar cycle, showing the Sun’s sunspot activity in October. As I have done every month since 2010, I am posting it here, with annotations to give it context.

The decline in sunspot continue steadily, matching the red prediction curve except that, as it has for this entire solar maximum, the number of sunspots continues to be less than expected. Not only did the ramp up start later and not quite reach the levels predicted, the ramp down started early. Overall, this now ending solar maximum is the weakest in a century. The big question remains: Is the Sun about to head into its first Grand Minimum since the 1600s, or is this weak maximum a one-time event to be followed by stronger activity in later cycles.

No matter what anyone tells you, no one knows.

October 2015 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.

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Failed GPS satellites to test Einstein’s theory

8:52 am

Making lemonade from lemons: Scientists are going to repurpose two GPS satellites — launched into wrong orbits and thus useless for GPS — to conduct a test of Einstein’s theory of general relativity.

The satellites, operated by the European Space Agency (ESA), were mislaunched last year by a Russian Soyuz rocket that put them into elliptical, rather than circular, orbits. This left them unfit for their intended use as part of a European global-navigation system called Galileo.

But the two crafts still have atomic clocks on board. According to general relativity, the clocks’ ‘ticking’ should slow down as the satellites move closer to Earth in their wonky orbits, because the heavy planet’s gravity bends the fabric of space-time. The clocks should then speed up as the crafts recede.

On 9 November, ESA announced that teams at Germany’s Center of Applied Space Technology and Microgravity (ZARM) in Bremen and the department of Time–Space Reference Systems at the Paris Observatory will now track this rise and fall. By comparing the speed of the clocks’ ticking with the crafts’ known altitudes — pinpointed within a few centimetres by monitoring stations on the ground, which bounce lasers off the satellites — the teams can test the accuracy of Einstein’s theory.

There actually is little uncertainty here. No one expects this experiment to disprove Einstein’s theory, but the failed spacecraft provide a great opportunity to measure things at an accuracy never previously attempted, which in turn will help improve future GPS design.

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Planning the coming end of Rosetta

8:44 am

The scientists and engineers operating Rosetta have begun planning the mission’s spectacular finale, when they will spend several months orbiting within six miles of Comet 67P/C-G’s surface before very gently crashing the spacecraft on the surface.

Because of many factors, Rosetta is not expected to survive the impact, no matter how gently it lands. However, the data it will send back in its final months as it makes tighter and tighter orbits should be well worthwhile.

In related news, the science team has released an animation, posted below the fold, of their re-creation of the flight and crash landing of Philae on the comet.
» Read more

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Ground-breaking for the Giant Magellan Telescope in Chile

10:07 pm

Even as construction of the Thirty Meter Telescope (TMT) in Hawaii remains stalled because of protesters, ground has now been broken in Chile for the construction of the Giant Magellan Telescope (GMT).

The unique design of the telescope combines seven of the largest mirrors that can be manufactured, each 8.4 meters (27 feet) across, to create a single telescope effectively 25 meters or 85 feet in diameter. The giant mirrors are being developed at the University of Arizona’s Richard F. Caris Mirror Laboratory. Each mirror must be polished to an accuracy of 25 nanometers or one millionth of an inch.

One giant mirror has been polished to meet its exacting specifications. Three others are being processed, and production of the additional mirrors will be started at the rate of one per year. The telescope will begin early operations with these first mirrors in 2021, and the telescope is expected to reach full operational capacity within the next decade.

Assuming TMT ever gets built, it will, unlike GMT, be made up of many small segments.

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Earth-sized exoplanet found only 39 light years away

10:01 pm

Worlds without end: Astronomers have discovered an exoplanet only slightly bigger then the Earth, and it’s only 39 light years away.

Berta-Thompson and the others estimate that GJ 1132b has a diameter of about 9,200 miles, slightly bigger than Earth. Its mass, however, is thought to be 60 percent greater than Earth’s. Its home star — GJ 1132 — is a red dwarf one-fifth the size of our sun. The planet circles every 1.6 days from just 1.4 million miles out, thus the heat wave. A slight dip in the starlight every 1.6 days was the giveaway for the observing team. “Our ultimate goal is to find a twin Earth,” said astronomer David Charbonneau of the Harvard-Smithsonian Center for Astrophysics, one of the authors, “but along the way we’ve found a twin Venus.”

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Stars in the Milky Way so old they predate it

5:00 pm

Astronomers have discovered stars inside the Milky Way that are thought to be so old that they were formed prior to the existence of the galaxy, and that the Milky Way formed around them.

The stars, found near the centre of the Milky Way, are surprisingly pure but contain material from an even earlier star, which died in an enormous explosion called a hypernova. “These pristine stars are among the oldest surviving stars in the Universe, and certainly the oldest stars we have ever seen,” said Louise Howes, lead author of the study published in the latest issue of Nature. “These stars formed before the Milky Way, and the galaxy formed around them,” said Ms Howes, a PhD student at the ANU Research School of Astronomy and Astrophysics.

Not surprisingly, the discovery challenges theories that describe the early universe.

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Ice volcanoes, spinning moons, and more proof of geologic activity

3:28 pm

The New Horizons science team has released more results from the spacecraft’s July 14 fly-by, revealing the existence of what look like two giant ice volcanoes on Pluto, data that suggests the smaller moons spin like tops, and a census of Pluto’s craters that show them distributed very unevenly across the planet’s surface, suggesting that large parts of Pluto’s surface have been resurfaced and thus have been geologically active.

One discovery gleaned from the crater counts also challenges the most popular theory about the formation of objects in the Kuiper Belt.

Crater counts are giving the New Horizons team insight into the structure of the Kuiper Belt itself. The dearth of smaller craters across Pluto and its large moon Charon indicate that the Kuiper Belt likely had fewer smaller objects than some models had predicted. This leads New Horizons scientists to doubt a longstanding model that all Kuiper Belt objects formed by accumulating much smaller objects of less than a mile wide. The absence of small craters on Pluto and Charon support other models theorizing that Kuiper Belt objects tens of miles across may have formed directly, at their current—or close to current—size.

In fact, the evidence that many Kuiper Belt objects could have been “born large” has scientists excited that New Horizons’ next potential target – the 30-mile-wide (40-50 kilometer wide) KBO named 2014 MU69 – which may offer the first detailed look at just such a pristine, ancient building block of the solar system.

As always, the results here are significantly uncertain. They are giving us a glimpse into the geology of rocky planets far from stars, but only a glimpse. I guarantee that any theories formed from this data will be incomplete and will likely be proven wrong.

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Why cold fusion and NASA’s EM Drive are most likely frauds

7:55 am

Link here. The writer does a nice job of explaining why impossible engines that appear to defy basic laws of physics are almost certainly incapable of doing what they promise, and are likely frauds.

An extraordinary result has to come with extraordinary evidence. When someone claims they have come up with something that can do something that engineers have been unable to do for centuries — since the very beginnings of the Industrial Age — I get very very suspicious, especially when their evidence is scanty and their data is not open for study.

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Two Mauna Kea protesters convicted but get minor sentences

8:29 am

Two protesters who blocked a road leading to the summit of Mauna Kea to block construction vehicles for the Thirty Meter Telescope (TMT) have been convicted of misdeamenors and given very minor sentences.

The state requested six months’ probation, and that they stay off Mauna Kea Access Road for the period of probation. Prosecutors also requested 72 hours of community service in lieu of a $500 fine. Fujiyoshi [one of the protesters] asked for a jail sentence instead of community service, and was sentenced to five days. He will serve one day in jail, with credit for time served; six months’ probation; and was ordered to remain off the access road. Lindsey-Kaapuni [the other protester] argued against probation, and was sentenced to 100 hours of community service.

The state here has no easy solution. If it demands severe punishment the press will make the protesters martyrs. If it lets them off then the protesters will know they can protest as much as they want and face no consequences.

Right now I do not see TMT ever getting built on Mauna Kea. I also see the slow removal of the telescopes already there to be certain, given time. The protesters are in control, and they oppose this search for knowledge about the universe.

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No sign of alien civilization at distant star

9:09 pm

The uncertainty of science: Two weeks of targeted observations by the Allen Telescope Array in California have detected no clear signal of an alien civilization at the star KIC 8462852 where Kepler observations have seen variations that could possibly be caused by giant alien structures.

Two different types of radio signals were sought: (1) Narrow-band signals, of order 1 Hz in width, such as would be generated as a “hailing signal” for societies wishing to announce their presence. This is the type of signal most frequently looked for by radio SETI experiments.  (2) Broad-band signals that might be due to beamed propulsion within this star system.  If astroengineering projects are really underway in the vicinity of KIC 8462852, one might reasonably expect the presence of spacecraft to service this activity.  If these craft are propelled by intense microwave beams, some of that energy might manifest itself as broad-band radio leakage. “This is the first time we’ve used the Allen Telescope Array to look for relatively wide-band signals, a type of emission that is generally not considered in SETI searches,” said SETI Institute scientist Gerry Harp.

Analysis of the Array data show no clear evidence for either type of signal between the frequencies of 1 and 10 GHz.  This rules out omnidirectional transmitters of approximately 100 times today’s total terrestrial energy usage in the case of the narrow-band signals, and ten million times that usage for broad band emissions.

The data shows no sign of alien civilization, but it also does not eliminate the possibility. More detailed observations are required to do that.

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A closer look at the fake sea level data

7:22 am

On Saturday I had posted a link to a very detailed article that strongly suggested that the alterations to the sea level rise data that scientists at the Colorado Sea Level Research Group were doing were either fraudalent or very very poorly thought out. One of the regular readers of Behind the Black, Edward, posted such a detailed and well-researched analysis of this story that I thought it worthwhile to promote it to the main page. Edward has given me permission to do so and so here it is:

It is reasonable for us to consider the possibility that a fraud is being perpetrated upon us.

1) Explaining data and the differences between the data taken and the data used is basic science; more basic than Science 101, it is middle school science. It is the first thing taught about data reporting in the first science class in which a student is required to collect data. Thus for the Colorado Sea Level Research Group at the University of Colorado to ignore the data discrepancy is a violation of basic science.
» Read more

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Recreating the changing giant starspots on a distant star

11:46 pm

Astronomers have recreated what they think is the evolution of the giant sunspots on a distant star, covering the period from 2006 to 2012.

More importantly, Künstler’s team measured the time it takes for starspots to decay and used that information to estimate properties of the star’s magnetic field. For example, the star’s activity cycle appears to last about 26 years, more than double the Sun’s 11-year cycle.

You can see a video of this recreation at the link.

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Crowded Mexico City and colonization of space

11:15 pm

This week Diane and I are in Mexico with friends doing some sightseeing. As is my habit, I can’t just enjoy the sights I have to ask a lot of questions while trying to get an impression of the place, its culture, its environment, its atmosphere, and its politics. Not surprisingly, the answers to some of those questions pointed me upward beyond the surface of the Earth. To understand why, read on.

Today we toured the inner parts of Mexico City, both on foot and by bus and subway (or the Metro as they call it here). I have spent considerable time in many of the world’s major cities, growing up in New York and visiting at length Moscow, Kiev, Prague, London, Chicago, Los Angeles and others. Mexico City has many of the same features you’d expect for this kind of big city, lots of people, lots of traffic, lots of buildings packed tight together, and lots of wealth and poverty sitting side-by-side.

Mexico City traffic

Mexico City however to me seemed to be most crowded and the most packed of any city I have ever visited or lived in. Its size and population probably rivals that of the entire New York metropolitan area, but somehow the traffic and crowds and architecture seemed more piled on top of each other with far less breathing room.

First was the traffic. Everywhere we went it was wall to wall vehicles. The major highways were never quiet, even at night. Nor could I see much difference between midday and rush hours. The picture on the right shows us heading from in from an outer neighborhood where we were staying to take the subway into the center of the city. Not only was it bumper-to-bumper, but if you look out in the distance the road is bumper-to-bumper as far as the eye can see. My host Alfonso added at one point that in order to avoid this traffic many people routinely leave for work before 5 am and come home after 8 pm. Schools have multiple shifts, including ones at night.

A side note: The tall rectangular structures in the foreground are not buildings. This is a work of art, five several hundred foot tall cinderblock structures supposedly forming a hand pointing up, with the thicker yellow tower in the front representing the thumb.
» Read more

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Tomato harvesting

6:01 pm

An evening pause: Another video suggested by Phill Oltmann illustrating how engineering has revolutionized the agricultural field. In this case its tomatoes, which I think illustrates quite well why mass produced tomatoes are simply not as good as vine grown tomatoes from your garden. Assuming the tomatoes in this video are not intended for canning, they have to be tough to withstand the harvesting process so that they remain whole for the fruit stand.

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Grizzly bear no longer endangered in Yellowstone

4:57 pm

Good news! Federal wildlife officials have determined that the grizzly bear population in and around Yellowstone has recovered so well that they have the option of removing the species from the endangered species list.

The latest count of grizzlies in the Yellowstone region puts the estimated population of the hump-shouldered bruins at just over 750, well exceeding the government’s recovery goal of 500 animals, according to the U.S. Fish and Wildlife Service. That compares with just 136 believed left in the Yellowstone ecosystem – encompassing parts of Wyoming, Montana and Idaho – when grizzlies were formally listed as threatened throughout the Lower 48 states in 1975, after they were hunted, trapped and poisoned to near extinction.

Not surprisingly, the article notes how environmental and American Indian groups oppose changing the bear’s status. Want to bet that they win the day and the bear remains endangered? Science really has very little to do with the endangered species act these days. It is all politics.

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A hybrid coyote/wolf prospers in the eastern U.S.

4:45 pm

A new hybrid species, two-thirds coyote and one-third wolf with a little bit of dog, has spread throughout the eastern United States in the past century.

The animal’s range has encompassed America’s entire north-east, urban areas included, for at least a decade, and is continuing to expand in the south-east following coywolves’ arrival there half a century ago. This is astonishing. Purebred coyotes never managed to establish themselves east of the prairies. Wolves were killed off in eastern forests long ago. But by combining their DNA, the two have given rise to an animal that is able to spread into a vast and otherwise uninhabitable territory.

Called either the eastern coyote or the coywolf, it is estimated that their population could now be as high as a million.

Posted from Mexico City.

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China unveils model of planned 2020 Martian probe

7:58 am

The competition heats up: China today unveiled a one-third scale model of its planned Martian lander/rover, scheduled for launch in 2020.

If they succeed in putting a lander and rover on Mars, China will have clearly demonstrated the capability to do almost anything in space that the United States can do. The competition in the coming decades should thus be most interesting.

Posted from Tucson International Airport.

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French television weatherman fired for doubting global warming

10:16 am

The coming dark age: A leading French television weatherman has been fired because he published a book expressing skepticism about global warming.

He said he was inspired to write the book after France’s Foreign Minister Laurent Fabius met with TV meteorologists and asked them to highlight climate change issues in their broadcasts. “I was horrified by this speech,” Verdier told French magazine Les Inrockuptibles last month. In his book, Verdier accuses state-funded climate change scientists of having been “manipulated” and “politicised”, even accusing the Intergovernmental Panel on Climate Change (IPCC) of publishing deliberately misleading data

In other words, he dared to expose the political roots of global warming that has nothing to do with science, and was thus immediately fired.

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Rosetta special science issue

9:23 am

For those who want to read some interesting science papers, on Friday the journal Astronomy & Astrophysics published a special issue devoted to the results from Rosetta and Philae.

The issue includes 46 papers, many of which are open access and thus available at no cost to the general public. Many were published previously and include their press releases. These earlier results have already been posted here at BtB, but now they the results are gathered together in one place.

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