Tag: astronomy

Astronomers find 20 more exoplanet candidates in Kepler archive

8:30 am

Worlds without end: Astronomers reviewing the Kepler archive have found 20 more exoplanet candidates, including one that has a mass about 97 percent of the Earth with an orbit 395 days long circling a star like the Sun.

The planet would be colder than Earth, as its star is slightly cooler than the Sun, and its orbit is slightly farther away. Nonetheless, this is an amazing twin, and would certainly be a prime target when interstellar travel becomes routine.

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The first large object identified coming from interstellar space

6:38 pm

Astronomers think they have spotted the first large object to come from beyond the solar system.

Based on its apparent brightness, dynamicist Bill Gray calculates that it would have a diameter of about 160 meters (525 feet) if it were a rock with a surface reflectivity of 10%. “It went past the Sun really fast,” Gray notes, “and may not have had time to heat up enough to break apart.”

Now it’s headed out of the solar system, never to return. It passed closest to Earth on October 14th at a distance of about 24,000,000 km (15,000,000 miles), and astronomers worldwide have been tracking it in the hopes of divining its true nature — especially whether it’s displaying any cometary activity.

…According to Gray, Comet PanSTARRS appears to have entered the solar system from the direction of the constellation Lyra, within a couple of degrees of right ascension 18h 50m, declination +35° 13′. That’s tantalizingly close to Vega — and eerily reminiscent of the plot of the movie Contact — but its exact path doesn’t (yet) appear to link any particular star.

This object entered the solar system moving at 26 km (16 miles) per second. At that speed, in 10 million years it would traverse 8,200,000,000,000,000 km — more than 850 light-years.

Reminds me of a really good science fiction novel I read recently. They should keep an eye on it for as long as they can, just in case it suddenly changes course and settles into a more circular orbit around the Sun. In the unlikely case it does that, it might just be the biggest discovery in history.

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NASA instrument for European space telescope flawed and must be rebuilt

5:29 pm

The NASA instrument for Europe’s Euclid optical/near-infrared space telescope has been found defective and must be rebuilt, thus delaying the launch of the telescope by at least one year.

What interested me about this telescope is its goals and specifications:

Euclid is a two-ton space telescope selected by ESA in 2011 as a medium-class mission in its Cosmic Vision program of space science missions. The spacecraft features a 1.2-meter telescope with visible and near-infrared instruments to study dark energy and dark matter, which combined account for about 95 percent of the universe. Euclid will operate at the Earth-sun L-2 Lagrange point, 1.5 million kilometers from Earth, that is used by other infrared astronomy missions.

With a mirror about half the size of Hubble’s, this telescope will act as a partial replacement and back up for it. In fact, it will likely make numerous ground-breaking discoveries, as every optical telescope placed above the atmosphere has so far done.

Meanwhile, the article provided no information on the flaws, who built the flawed instrument, and who will pay for the delays its failure will cause.

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Astronomers reduce estimate of still undiscovered dangerous asteroids

11:49 am

Astronomers have now reduced [pdf] their estimate of the number of still undiscovered dangerous Near Earth Asteroids (NEAs) that could impact the Earth from 100 to less than 40.

Observers have been cataloging potentially hazardous asteroids for decades. Based on the number of finds, the area of sky explored, and the limiting brightness our telescopes and cameras can reach, researchers can estimate what fraction of the NEA population has been detected so far and how many more objects lurk undiscovered. Harris has published numerous such estimates over the years. Recently he realized that his estimates have been plagued by a seemingly innocuous but nonetheless consequential round-off error. Once corrected, the estimated number of large (diameter > 1 kilometer) NEAs remaining to be discovered decreases from more than 100 to less than 40.

To put it mildly, there is a lot of uncertainty here. This also reminds me of the cavers’ joke question: “How many miles of unexplored passages does this cave have?”

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Nearby asteroid orbits both the Earth and the Sun

11:42 am

Worlds without end: Astronomers have determined that a recently discovered object with a weird solar orbit that also has it loop around the Earth each year is an asteroid, not space junk.

The asteroid is dubbed 2016 HO3. What is most interesting about this story to me however was this tidbit:

“Of the near-Earth objects we know of, these types of objects would be the easiest to reach, so they could potentially make suitable targets for exploration,” said Veillet, director of the LBT Observatory. “With its binocular arrangement of two 8.4-meter mirrors, coupled with a very efficient pair of imagers and spectrographs like MODS, LBT is ideally suited to the characterization of these Earth’s companions.”

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Astronomers detect neutron star merger in both light and gravitational waves

9:00 am

Big news! Astronomers from dozens of telescopes on the ground and in space have observed for the first time the light burst caused by the merger of two neutron stars because earlier observations of the merger’s gravitational wave and gamma ray burst told them where to look in the sky.

On 17 August 2017 the NSF’s Laser Interferometer Gravitational-Wave Observatory (LIGO) in the United States, working with the Virgo Interferometer in Italy, detected gravitational waves passing the Earth. This event, the fifth ever detected, was named GW170817. About two seconds later, two space observatories, NASA’s Fermi Gamma-ray Space Telescope and ESA’s INTErnational Gamma Ray Astrophysics Laboratory (INTEGRAL), detected a short gamma-ray burst from the same area of the sky.

The LIGO–Virgo observatory network positioned the source within a large region of the southern sky, the size of several hundred full Moons and containing millions of stars. As night fell in Chile many telescopes peered at this patch of sky, searching for new sources. These included ESO’s Visible and Infrared Survey Telescope for Astronomy (VISTA) and VLT Survey Telescope (VST) at the Paranal Observatory, the Italian Rapid Eye Mount (REM) telescope at ESO’s La Silla Observatory, the LCO 0.4-meter telescope at Las Cumbres Observatory, and the American DECam at Cerro Tololo Inter-American Observatory. The Swope 1-metre telescope was the first to announce a new point of light. It appeared very close to NGC 4993, a lenticular galaxy in the constellation of Hydra, and VISTA observations pinpointed this source at infrared wavelengths almost at the same time. As night marched west across the globe, the Hawaiian island telescopes Pan-STARRS and Subaru also picked it up and watched it evolve rapidly.

Press releases today from numerous other observatories are too numerous to link here, and most essentially say the same thing. The key facts so far gleaned however are intriguing:

Distance estimates from both the gravitational wave data and other observations agree that GW170817 was at the same distance as NGC 4993, about 130 million light-years from Earth. This makes the source both the closest gravitational wave event detected so far and also one of the closest gamma-ray burst sources ever seen

This event also highlights the advantages of observing the universe in as many ways as possible. Some phenomenon get to us sooner, and thus provide us clues on where to look with other tools. Without the gravitational wave and gamma ray burst detectors, on Earth and in space, the other optical and infrared telescopes would have almost certainly not have recorded this merger.

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Astronomers discover ring around object beyond Neptune

10:14 am

Observations of the trans-Neptunian object Haumea has revealed that not only is is shaped like a football due to its fast rotation, it has a ring.

Haumea is an interesting object: it rotates around the Sun in an elliptic orbit which takes it 284 years to complete (it presently lies fifty times further from the Sun than the Earth), and it takes 3.9 hours to rotate around its axis, much less than any other body measuring more than a hundred kilometers long in the entire Solar System. This rotational speed causes it to flatten out, giving it an ellipsoid shape similar to a rugby ball. The recently published data reveal that Haumea measures 2.320 kilometers in its largest axis – almost the same as Pluto – but lacks the global atmosphere that Pluto has.

“One of the most interesting and unexpected findings was the discovery of a ring around Haumea. Until a few years ago we only knew of the existence of rings around the giant planets; then, recently, our team discovered that two small bodies situated between Jupiter and Neptune, belonging to a group called centaurs, have dense rings around them, which came as a big surprise. Now we have discovered that bodies even farther away than the centaurs, bigger and with very different general characteristics, can also have rings,” says Pablo Santos-Sanz, another member of the IAA-CSIC team.

The more we see of these distant objects beyond Neptune the more I suspect that they are going to be puffy, not very dense, and surrounded by miscellaneous objects. The gravity and environment that far from the Sun simply allows them to not coalesce as happened in the inner solar system.

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First discoveries from China’s FAST radio telescope

8:58 am

Astronomers using China’s new FAST radio telescope have announced its first discoveries, the identification of two pulsars,

The new pulsars PSR J1859-01 and PSR J1931-02, also referred to as FAST pulsar #1 and #2 (FP1 and FP2), were detected on August 22 and 25, and were confirmed by the Parkes telescope in Australia on September 10. “FP1 is a pulsar with a spin period of 1.83 second and an estimated distance of 16 thousand light-years, and FP2, is a pulsar with a spin period of 0.59 second and an estimated distance of 4,100 light years,” said Li Di, Deputy Chief Engineer of FAST Project at the National Astronomical Observatories (NAOC), on Tuesday.

FAST’s gigantic size will allow it to pinpoint many similar astronomical objects previously beyond the resolution of radio telescopes.

Note that there is still no word on whether China has found a scientist to head FAST operations.

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More strange behavior from Tabby’s Star

8:56 am

Astronomers reviewing past data of KIC 8462852, known as Tabby’s Star to the public, have discovered that not only has it been dimming in a variety of inexplicable ways, it also has brightened twice in a manner that eliminates all past theories for its behavior, including alien megastructures.

The latest findings from Carnegie’s Josh Simon and Benjamin Shappee and collaborators take a longer look at the star, going back to 2006—before its strange behavior was detected by Kepler. Astronomers had thought that the star was only getting fainter with time, but the new study shows that it also brightened significantly in 2007 and 2014. These unexpected episodes complicate or rule out nearly all the proposed ideas to explain the star’s observed strangeness.

Up until now, all the changes to the star had involved dimming, though in ways that did not fit any present theory of stellar evolution. Thus, astronomers theorized that the dimming was caused by something moving in front of the star, from comets to dust to alien structures. This new data of two significant brightening events makes all those theories invalid.

Update: More news about Tabby’s Star: Using two space telescopes as well as amateur telescopes on the ground scientists have determined that the dimming must come from an uneven dust cloud.

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Hawaii’s land board votes 5-2 in favor of TMT

9:17 am

After lengthy hearings, Hawaii’s land board has voted 5 to 2 to approve the construction permit for building the Thirty Meter Telescope on top of Mauna Kea.

The board placed 43 conditions on the permit, including a previously negotiated plan requiring the University of Hawaii to decommission three existing telescopes atop Mauna Kea, where the TMT is to be built, and barring any future telescopes on the mountain. In a statement, Suzanne Case, chair of the board, said: “This was one of the most difficult decisions this Board has ever made. The members greatly respected and considered the concerns raised by those opposed to the construction of the Thirty-Meter Telescope at the Mauna Kea Science Reserve.”

TMT opponents tell ScienceInsider that they will appeal the decision. Kealoha Pisciotta, a Hawaiian cultural practitioner and a plaintiff in the case against the TMT permit, said she believed the board had rubber-stamped the permit, and the decision seemed like a foregone conclusion. “They did not deliberate. They did not properly consider or take into account the evidence,” she said. [emphasis mine]

They did not deliberate? The decision was announced with a 345 page document [pdf] outlining the long history of this permit process, including a detailed description of the previous process that had given its approval before protests required a second hearing followed by the numerous and endless testimony since.

This “Hawaiian cultural practitioner” (or what I call a typical race hustler) is either lying or willfully ignorant, and actually could be a poster-boy for modern intellectualism, which always puts race and ethnicity above facts and reasoned debate. And if you don’t believe me, read the pdf at the link above. Search for Pisciotta’s name and read her testimony. It reeks of ignorance and dishonesty, all colored by a racist love of her native race and a hatred of all others.

I still do not expect TMT to be built in Hawaii. The race hustlers rule the Democratic Party, and the Democratic Party rules Hawaii. They will allow the stalling to continue until the consortium building TMT will be forced to go elsewhere.

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Webb Space Telescope delayed again

11:32 pm

NASA announced today that they are further delaying the launch of the James Webb Space Telescope from October 2018 to late spring 2019.

NASA’s James Webb Space Telescope now is planning to launch between March and June 2019 from French Guiana, following a schedule assessment of the remaining integration and test activities. Previously Webb was targeted to launch in October 2018. “The change in launch timing is not indicative of hardware or technical performance concerns,” said Thomas Zurbuchen, associate administrator for NASA’s Science Mission Directorate at Headquarters in Washington. “Rather, the integration of the various spacecraft elements is taking longer than expected.”

As part of an international agreement with the ESA (European Space Agency) to provide a desired launch window one year prior to launch, NASA recently performed a routine schedule assessment to ensure launch preparedness and determined a launch schedule change was necessary. The careful analysis took into account the remaining tasks that needed to be completed, the lessons learned from unique environmental testing of the telescope and science instruments at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, and the current performance rates of integrating the spacecraft element.

Webb’s original launch date was supposed to be 2011, making its launch now verging on a decade late. The original budget for the telescope was supposed to be $1 billion. It is now expected to cost more than $9 billion. Like SLS/Orion, this project more resembles feather-bedding, providing NASA employees and the contractors involved a steady paycheck, regardless of whether they ever get anything done. In fact, both Webb and SLS/Orion seemed designed to encourage failure. The project never gets cancelled no matter what goes wrong. Instead, more money gets poured in.

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Hubble spots most distance active comet yet

11:13 am

Comet C/2017 K2

Using the Hubble Space Telescope astronomers have imaged a comet that is sublimating material at a distance from the Sun farther than any previously known comet, out beyond Saturn.

“K2 is so far from the Sun and so cold, we know for sure that the activity — all the fuzzy stuff making it look like a comet — is not produced, as in other comets, by the evaporation of water ice,” said lead researcher David Jewitt of the University of California, Los Angeles. “Instead, we think the activity is due to the sublimation [a solid changing directly into a gas] of super-volatiles as K2 makes its maiden entry into the solar system’s planetary zone. That’s why it’s special. This comet is so far away and so incredibly cold that water ice there is frozen like a rock.”

Based on the Hubble observations of K2’s coma, Jewitt suggests that sunlight is heating frozen volatile gases – such as oxygen, nitrogen, carbon dioxide, and carbon monoxide – that coat the comet’s frigid surface. These icy volatiles lift off from the comet and release dust, forming the coma. Past studies of the composition of comets near the Sun have revealed the same mixture of volatile ices.

The significance here is that by studying the comet’s activity scientists will be able to identify some of these volatile gases, which in turn will tell them something about the make-up of the outermost fringes of the solar system.

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Status of Arecibo radio observatory

9:16 am

It appears that, while Puerto Rico itself suffered devastating damage from Hurricane Maria, the Arecibo Observatory came through relatively unscathed.

The surface of the dish was largely unscathed, and the observatory’s most vulnerable component, the instrument platform suspended high above the dish by cables strung from three towers, each more than 80 meters tall, was still in place and seemed undamaged, says Schmelz. She is based at the Columbia, Maryland, headquarters of one of Arecibo’s operators, the Universities Space Research Association, and spoke with staff in Puerto Rico who first used a ham radio and then a single working satellite phone. But the roofs on some observatory buildings were blown off, the sinkhole under the dish was flooded, and other equipment was damaged by rain and fallen trees. Most significantly, a large portion of a 29-meter-long antenna—the 430-megahertz line feed used for studying the upper atmosphere—appears to have broken off and fallen from the platform into the dish. Mathews estimates a bill of several million dollars to replace the line feed alone.

Because of the significant infrastructure damage across the island, there will be significant delays in getting any of this fixed. Since the telescope is already being considered for shut down due to budget issues, these delays could lead to that shut down.

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Gravitational waves from black hole collision detected

10:47 am

Three Earth gravitational wave observatories have detected the waves coming from the same collision of two black holes.

The collision was observed Aug. 14 at 10:30:43 a.m. Coordinated Universal Time (UTC) using the two National Science Foundation (NSF)-funded Laser Interferometer Gravitational-Wave Observatory (LIGO) detectors located in Livingston, Louisiana, and Hanford, Washington, and the Virgo detector, funded by CNRS and INFN and located near Pisa, Italy.

The detection by the LIGO Scientific Collaboration (LSC) and the Virgo collaboration is the first confirmed gravitational wave signal recorded by the Virgo detector.

Based on the data obtained, they estimate that the two black holes 25 and 31 times the mass of the Sun and are about 1.8 billion light years away.

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Dark energy might not exist

6:22 pm

The uncertainty of science: A new model for the universe that omits dark energy produces a better fit to what is know than previous theories that included it.

The new theory, dubbed timescape cosmology, includes the known lumpiness of the universe, while the older traditional models that require dark energy do not.

Timescape cosmology has no dark energy. Instead, it includes variations in the effects of gravity caused by the lumpiness in the structure in the universe. Clocks carried by observers in galaxies differ from the clock that best describes average expansion once variations within the universe (known as “inhomogeneity” in the trade) becomes significant. Whether or not one infers accelerating expansion then depends crucially on the clock used. “Timescape cosmology gives a slightly better fit to the largest supernova data catalogue than Lambda Cold Dark Matter cosmology,” says Wiltshire.

He admits the statistical evidence is not yet strong enough to definitively rule in favour of one model over the other, and adds that future missions such as the European Space Agency’s Euclid spacecraft will have the power to distinguish between differing cosmology models.

Both models rely on a very weak data set, based on assumptions about Type 1a supernovae that are likely wrong. It is thus likely that neither explains anything, as neither really has a good picture of the actual universe.

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The kittens of Saturn’s rings

11:16 am

The scientists who used Cassini to identify about 60 transient clumps in Saturn’s rings have dubbed them “kittens” and have been naming them appropriately.

Saturn’s kittens are a group of small clumps and baby moons, or moonlets, that occupy the planet’s F ring. Like the rest of Saturn’s rings, this thin outer ring is made up of countless particles that range in size. When enough of those particles bump into one another and stick together, they aggregate into larger clumps — and become eligible for a kitten name.

So far, the list of Saturn’s kitten names includes several classics, like Fluffy, Garfield, Socks and Whiskers. These are unofficial nicknames for more-complicated (and less adorable) official titles like “Alpha Leonis Rev 9” (aka, Mittens). The technical names for these features come from events called stellar occultations, during which Cassini was able to detect the little clumps. In a stellar occultation, a star passes behind Saturn’s rings from Cassini’s point of view.

Most of these clumps will likely never be found again, so their unofficial kitten names are essentially just for fun.

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Scientists finally image SMART-1 lunar impact site

11:00 am

SMART-1 impact site

Eleven years after the European SMART-1 probe was sent crashing onto the Moon’s surface, scientists have finally identified in a Lunar Reconnaissance Orbiter image that crash site.

The image is shown on the right, reduced and cropped to post here.

The images show a linear gouge in the surface, about four metres wide and 20 metres long, cutting across a small pre-existing crater. At the far end, a faint fan of ejecta sprays out to the south. Foing said: “The high resolution LRO images show white ejecta, about seven metres across, from the first contact. A north-south channel has then been carved out by the SMART-1 spacecraft body, before its bouncing ricochet. We can make out three faint but distinct ejecta streams from the impact, about 40 metres long and separated by 20-degree angles.”

Stooke said: “Orbit tracking and the impact flash gave a good estimate of the impact location, and very close to that point was a very unusual small feature. It now seems that impacts of orbiting spacecraft, seen here from SMART-1, and also in the cases from GRAIL and LADEE, will form elongated craters, most of whose rather faint ejecta extends downrange”.

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Post-hurricane update from Arecibo radio telescope

4:55 pm

USRA, the university consortium that operates the Arecibo radio telescope in Puerto Rico, has released an update on the observatory’s condition following Hurricane Maria.

Currently, we have no contact with the Observatory. One observatory staff member located in Arecibo Town contacted via short-wave radio reports that trees are down, power is out, houses damaged and roads impassable. We have no reason to believe that staff sheltered at Arecibo Observatory are in immediate danger since they have generators, well water and plenty of food. This is a rapidly changing situation, and we are trying to do the best we can to contact USRA employees and find out their status.

Essentially, they don’t know much at this point.

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More hearings stalling TMT

5:31 pm

Stall, stall: After spending 44 days of hearings before a retired judge, Hawaii is now forcing the consortium that wants to build the Thirty Meter Telescope on Mauna Kea to undergo further hearings before the local land board.

Wednesday’s hearing in a Hilo hotel comes after the retired judge overseeing contested-case hearings for the Thirty Meter Telescope recommended granting the project a construction permit. Riki May Amano issued her recommendation in July after hearing testimony that spanned 44 days. Opponents and supporters are echoing much of the arguments made during those oftentimes emotional days of testimony.

This short article, which really says little, ends by noting that “it’s not clear when the board will make a decision.”

Well, it is clear to me that the authorities in Hawaii, run exclusively by today’s racially-focused Democratic Party, is stalling as much as they can in order to force TMT to go elsewhere. They know it will not be a popular decision to block the telescope, but they also don’t want it because the hustlers of race on the island are against it. And to the Democratic Party today, the only thing that matters is to appease these race hustlers. So, they stall, figuring they can get rid of the telescope that way without ever having to block it outright.

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Hubble finds binary asteroid that also acts like a comet

10:54 am

Worlds without end: Astronomers using the Hubble Space Telescope have identified a strange new object in the asteroid belt, two asteroids closely orbiting each other while also acting like a comet.

The images of 288P, which is located in the asteroid belt between Mars and Jupiter, revealed that it was actually not a single object, but two asteroids of almost the same mass and size, orbiting each other at a distance of about 100 kilometres. That discovery was in itself an important find; because they orbit each other, the masses of the objects in such systems can be measured.

But the observations also revealed ongoing activity in the binary system. “We detected strong indications of the sublimation of water ice due to the increased solar heating — similar to how the tail of a comet is created,” explains Jessica Agarwal (Max Planck Institute for Solar System Research, Germany), the team leader and main author of the research paper. This makes 288P the first known binary asteroid that is also classified as a main-belt comet.

The data also suggests that this binary has only existed as such for a few thousand years, and probably broke into two pieces because of its rotation. When this happened, it exposed water ice buried below the surface, which having been exposed to sunlight is sublimating away and producing the binary’s cometlike of a tail and coma.

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New theory for formation of main asteroid belt

11:56 am

The uncertainty of science: Using computer models, astronomers have developed a new completely different theory to explain the existence of the asteroid belt between Mars and Jupiter.

The asteroid belt (sometimes referred to as the main asteroid belt) orbits between Mars and Jupiter. It consists of asteroids and minor planets forming a disk around the sun. It also serves as a sort of dividing line between the inner rocky planets and outer gas giants. Current theory suggests that the asteroid belt was once much more heavily populated, but the gravitational pull of Jupiter flung approximately 99 percent of its former material to other parts of the solar system or beyond. Astronomers also assumed that Jupiter’s gravity prevented the material in the belt from coalescing into larger planets. In this new effort, the researchers propose a completely different explanation of the asteroid belt’s origin—suggesting that the belt started out as an empty space and was subsequently filled by material flung from the inner and outer planets.

The new theory is interesting in that it really illustrates how little we really know about the formation of our solar system. The simple fact is that either one of these theories might be the answer, even though they propose completely opposite initial conditions. We simply do not have enough information about solar system formation in general to constrain our models and determine which of these theories is right.

Until scientists have been able to study hundreds, if not thousands, of solar systems up close, these models will be nothing more than interesting exercises in computer modeling.

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Hubble spots a pitch-black exoplanet

9:44 am

Astronomers using the Hubble Space Telescope have determined that an exoplanet is practically pitch black, reflecting almost no light.

NASA’s Hubble Space Telescope has observed a planet outside our solar system that looks as black as fresh asphalt because it eats light rather than reflecting it back into space. This light-eating prowess is due to the planet’s unique capability to trap at least 94 percent of the visible starlight falling into its atmosphere.

The oddball exoplanet, called WASP-12b, is one of a class of so-called “hot Jupiters,” gigantic, gaseous planets that orbit very close to their host star and are heated to extreme temperatures. The planet’s atmosphere is so hot that most molecules are unable to survive on the blistering day side of the planet, where the temperature is 4,600 degrees Fahrenheit. Therefore, clouds probably cannot form to reflect light back into space. Instead, incoming light penetrates deep into the planet’s atmosphere where it is absorbed by hydrogen atoms and converted to heat energy.

Because the exoplanet is tidally locked, with one side always facing its sun and the other always in nightime, the nighttime face is estimated to be about 2,000 degrees cooler, and actually shows evidence of the existence of water vapor and clouds.

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Astronomers search for water on Trappist-1 ecoplanets

10:54 am

The uncertainty of science: New research suggests that the Earth-sized exoplanets circling Trappist-1 might have water, or might not.

The data suggests the inner planets likely have lost all their water, but the outer planets, some of which are in the habitable zone, could have water. The key word is “could.” They actually don’t yet have any data that says for sure whether water is there..

Posted as we drive through Kayenta in the Navaho Reservation.

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Astronomers produce best image yet of a star

2:11 pm

The uncertainty of science: Astronomers have produced the best image so far of the surface face of a star.

The star is Antares, and it provides some details of the star’s complex outer layers. If I was home and had good internet access, I’d post it here.

At the same time, it should be noted that this is not a real image. It is recreated from four telescopes, using interferometry to combine the images, and also includes it a great deal of assumptions and uncertainties in its creation.

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To protect students from eclipse some schools will close Monday, or will keep their students indoors

9:54 am

The coming dark age: Fearful of the thunder gods, some school administrators have decided to close their schools or to keep their students indoors so they can’t see the eclipse on Monday.

CBS Miami reports some local schools in South Florida are giving kids an excused absence or even the day off to enjoy the eclipse, while others have decided to keep students inside for their safety.

The Scottsdale Unified School District in Arizona decided it was just too dangerous to let kids view the eclipse, especially after some reports of fake eclipse glasses on the market that might put eyes at risk, CBS Phoenix affiliate KPHO reports. “So without us being able to control the equipment that’s being used, if it’s donated or something, and also when you’re talking about a large amount of children it’s also very difficult to convince all of the kids to not look up. That’s not to say our kids won’t be very well behaved but if there’s even a question that there could be something unsafe, Scottsdale’s not going to take the chance,” said Erin Helm with Scottsdale Unified.

The quote is from the second link above. The first link describes the decision of Ohio schools to close.

It is horrifying that there are school officials out there who would actually act to prevent children from experiencing the eclipse out of fear. Kids are smart enough to know not to look at the Sun, if you tell them not to. And it is the responsibility of the school to provide them the right kinds of eclipse glasses, which do not cost a lot and can easily be purchased.

In fact, it is revealing that the schools doing this are all public schools, and thus provides more evidence that the public schools might be the worst place to send kids to get educated.

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“One of the greatest discoveries of the century is based on these things and we don’t even know what they are, really.”

9:42 am

The uncertainty of science: New research suggests that astronomers have little understanding of the supernovae that they use to estimate the distance to most galaxies, estimates they then used to discover dark energy as well as measure the universe’s expansion rate.

The exploding stars known as type Ia supernovae are so consistently bright that astronomers refer to them as standard candles — beacons that are used to measure vast cosmological distances. But these cosmic mileposts may not be so uniform. A new study finds evidence that the supernovae can arise by two different processes, adding to lingering suspicions that standard candles aren’t so standard after all.

The findings, which have been posted on the arXiv preprint server and accepted for publication in the Astrophysical Journal, could help astronomers to calibrate measurements of the Universe’s expansion. Tracking type Ia supernovae showed that the Universe is expanding at an ever-increasing rate, and helped to prove the existence of dark energy — advances that secured the 2011 Nobel Prize in Physics.

The fact that scientists don’t fully understand these cosmological tools is embarrassing, says the latest study’s lead author, Griffin Hosseinzadeh, an astronomer at the University of California, Santa Barbara. “One of the greatest discoveries of the century is based on these things and we don’t even know what they are, really.”

The key to understanding this situation is to maintain a healthy skepticism about any cosmological theory or discovery, no matter how enthusiastically touted by the press and astronomers. The good astronomers do not push these theories with great enthusiasm as they know the feet of clay on which they stand. The bad ones try to use the ignorant mainstream press to garner attention, and thus funding.

For the past two decades the good astronomers have been diligently checking and rechecking the data and the supernovae used to discover dark energy. Up to now this checking seems to still suggest the universe’s expansion is accelerating on large scales. At the same time, our knowledge of supernovae remains sketchy, and thus no one should assume we understand the universe’s expansion rate with any confidence.

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Ten planetary probes track a solar eruption through the solar system

9:02 am

The path of an October 2014 solar eruption was tracked by ten different spacecraft, including Curiosity on the surface of Mars, as its blast moved outward through the solar system.

The measurements give an indication of the speed and direction of travel of the CME [Coronal Mass Ejection], which spread out over an angle of at least 116 degrees to reach Venus Express and STEREO-A on the eastern flank, and the spacecraft at Mars and Comet 67P Churyumov–Gerasimenko on the western flank.

From an initial maximum of about 1000 kilometers per second (621 miles per second) estimated at the sun, a strong drop to 647 kilometers per second (402 miles per second) was measured by Mars Express three days later, falling further to 550 kilometers per second (342 miles per second) at Rosetta after five days. This was followed by a more gradual decrease to 450–500 kilometers per second (280-311 miles per second) at the distance of Saturn a month since the event.

The CME was first detected by solar observatories Proba-2, SOHO, Solar Dynamics Observatory, and STEREO-A.It was then tracked as it moved outward by Venus Express, Mars Express, MAVEN, Mars Odyssey, Curiosity, Rosetta, Cassini, and even New Horizons and Voyager 2.

On my last appearance on Coast to Coast, I was specifically asked if the probes to Venus, Mars, and other planets have the capability to track solar events. I knew that the Voyager spacecraft had equipment to do this, but was unsure about other planetary probes. This article answers that question.

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Amazon refunding customers who bought fake eclipse glasses

9:43 am

Amazon is issuing refunds to any customers who bought fake eclipse glasses through the site.

It is essential for people who are going to view the eclipse to understand that as long as the Sun is even partially visible, even by a sliver, it can cause significant eye damage if viewed without proper protection. Make sure your eclipse glasses or filters are safe! And remember, only during the short 2 minute or so totality that will occur in the narrow strip across the country will it be safe to look at the Sun without protection. Even so, you must do so with great caution so that you don’t mistakenly view the Sun unprotected when it is partially exposed.

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Unexpected big storm on Neptune

9:17 am

The uncertainty of science: Astronomers have spotted a new very big storm on Neptune, occurring unexpectedly near the plane’s equator.

A large, high-pressure vortex system deep within Neptune’s atmosphere is thought to drive the white storm clouds. As methane gases rise up in the vortex, they cool below the condensation temperature, forming clouds in the same way that water vapor does on Earth.

The location of the vortex caught astronomers by surprise, though. “Historically, bright clouds have occasionally been seen on Neptune, but usually at latitudes closer to the poles, around 10 to 60 degrees north or south” says de Pater. “Never before has a cloud been seen at, nor close to the equator, or anything so bright.”

Neptune is the windiest planet in the solar system, with observed equatorial wind speeds of up to 1,000 miles per hour (450 m/s). Since wind speeds vary drastically with latitude, a storm crossing more than 30° of latitude should quickly break apart. Something, such as an underlying vortex, must be holding it together. But a long-lasting vortex right at the equator would be hard to reconcile with our current understanding of the planet’s atmosphere.

I think any theory about Neptune’s weather should treated with a great deal of skepticism. I am sure the theories are based on what is known, but what is known is very little. Until we have been able to observe this gas giant up close and for decades, our understanding of its weather is going to be sketchy, at best.

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Chinese engineers and astronomers fight over new telescope design

9:10 am

A dispute over the design of a new Chinese optical telescope has broken out between the astronomers who will use it and the engineers who will build it.

In April, an international committee convened by [Chinese Academy of Science’s] Center for Astronomical Mega-Science, which is responsible for the project, reviewed the competing designs and recommended the three-mirror option [the preference of astronomer Jiansheng Chen and China’s astronomers]. On 10 July, [Xiangqun Cui, the instrument’s chief engineer] organized her own review committee that picked the SYZ design as better. Cui’s panel “leaned toward one side,” Chen says. And one member says that the three-mirror design was not sufficiently presented, partly because no one from the Huazhong team was there. Cui and Su explain in their open letter that a member of their own group who knows it well introduced the Huazhong design. “Members were repeatedly reminded they could abstain from voting,” they write. One-third of the 21 committee members did abstain.

Meanwhile, to date, more than 130 young astronomers have signed an open letter to the astronomical community urging that the recommendations of the international panel be respected.

The fundamental disagreement, according to Chen, is “whether a large science project should be technically or scientifically oriented.” Cui and Su say the choice is between incorporating “rapidly developing new technologies” that ensure a long life for the facility, or “simply replicating a 10-meter telescope built 30 years ago.”

This spat reinforces the impression gained from the recent other story about China’s inability to find a manager for its newly built radio telescope. Its top-down management approach (where decisions are made by well-connected powerful bureaucrats at the top of the chain of command) produces office politics that generally does not lead to good technical decisions.

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