Tag: astronomy

Is mercury release cause of New Mexico solar observatory shutdown?

1:28 am

Story here. From the link:

The issue may be related to Mercury (the metal, not the planet). On a tip from a science journalist friend who covers telescopes and who has been there, I verified the observatory uses a vat of liquid mercury as a float bearing for the giant solar telescope. According to an internal NSO/NMSU document, that bearing is “high-risk” during maintenance. If there was a major mercury spill, it might explain why the Feds are there, with FBI providing security. The amount of Mercury is said to be in the “tens of gallons” range, which is next to impossible to come by in the commercial market these days, and if it were weaponized, it would make a very nasty dirty bomb. Perhaps there’s some security issue with the mercury on-site.

This is third hand, so it should be taken with a great deal of skepticism.

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Solar observatory closed for unstated security reasons

10:38 am

The National Solar Observatory facility at Sacramento Peak in New Mexico, managed by a consortium of universities, has been shut down temporarily for unstated security reasons.

The Sunspot Observatory is temporarily closed due to a security issue at the facility that’s located 17 miles south of Cloudcroft in the Sacramento Mountains Friday, an Association of Universities for Research in Astronomy (AURA) spokeswoman Shari Lifson said.

“The Association of Universities for Research in Astronomy who manages the facility is addressing a security issue at this time,” Lifson said. “We have decided to vacate the facility at this time as precautionary measure. It was our decision to evacuate the facility.”

She said she cannot comment on the specifics of the security issue.

This is a very strange story, especially because of the lack of information being released. What could have happened that required them to evacuate? And why can’t they release more details?

I can’t deny that my first thought was aliens, but this is a laughable and ridiculous idea. The facility merely looks up at the Sun, and is also a somewhat minor research facility. More likely they have had a serious employee problem, and are trying to take steps to prevent anyone from getting hurt.

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TESS releases its first batch of exoplanet candidates

9:59 am

The science team for the U.S.’s exoplanet space telescope TESS this week released its first batch of exoplanet candidates.

TESS scientists released the list so that other astronomers could make an initial determination as to whether these candidates are planets. There are 73 objects in this first batch, including some planets previously known from ground-based searches, says George Ricker, the mission’s principal investigator at the Massachusetts Institute of Technology in Cambridge. Perhaps 5 to 20% of the objects on the list will turn out to be false alarms, he says. Others, if confirmed, will join the ranks of newly discovered exoplanets.

Researchers expect TESS to find as many as 10,000 large planets. But its main goal is to discover and measure the masses of at least 50 small worlds no more than four times the size of Earth.

Meanwhile, Kepler has resumed operations despite being almost out of fuel. The science team there is attempting to squeeze every last ounce of data it can before the spacecraft’s fuel runs out.

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Arecibo gets upgrade, new funding

9:33 am

Back from the dead: Threatened with closure only last year due to lack of funds, then damaged badly from Hurricane Maria, the Arecibo radio telescope in Puerto Rico has not only obtained a new operational funding from a new partner but also a $6 million upgrade.

The money will help design and build a super-sensitive set of antennas to be installed at the focal point of Arecibo’s dish. The 166 antennas, together part of the phased-array feed to be installed in 2022, are expected to significantly increase Arecibo’s capabilities. The phased-array feed will boost the telescope’s sky survey speed, making it five to six times faster than it is now, and it’ll enable the telescope to look at a larger piece of sky at one time.

…This month’s announced upgrade comes after years of uncertainty about Arecibo’s operations. In September 2017 Hurricane Maria caused about $14 million in damage to the telescope and ancillary buildings, some of which is still being repaired today. The facility lost its 430-megahertz line feed, which was used for atmospheric studies. Pieces of the antenna fell and punctured panels in the primary reflector of the main dish, forcing the replacement of 80–90 of the panels. There was also significant flooding under the primary reflector, which damaged some of the lines and heating facilities. In addition, several pieces of electronic equipment, some imagers, and laser rangers were damaged. Three buildings — a maintenance facility, a heater/transmitter building and a family unit — were also partially or completely destroyed due to rock and tree debris.

The hurricane was only the latest challenge for the observatory, after Arecibo had fought off repeated threats of closure over the previous decade due to NSF funding concerns. The latest situation was resolved last February, when a consortium led by the University of Central Florida took over operation and management of the observatory, significantly lessening the burden on NSF.

While Arecibo is no longer the world’s largest single radio dish, having been topped by China’s FAST radio telescope, it appears at least for now better positioned to do research. China does not yet have the radio astronomers experienced enough to operate its telescope, and so FAST at present is significantly under-utilized.

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A gas giant exoplanet so hot it resembles a star

8:45 am

Link here. Key quote:

This sweltering exoplanet, located about 620 light-years away from Earth in the constellation Cygnus, is what astronomers call an “ultrahot Jupiter.” KELT-9b is a giant gas world like Jupiter, the largest planet in our solar system. But it’s way bigger — it has three times the mass and twice the diameter of Jupiter — and it orbits extremely close to its hot parent star, KELT-9.

“Ultrahot Jupiter” is an unofficial term for a hot Jupiter exoplanet with temperatures exceeding 3,100 degrees Fahrenheit (1,700 degrees Celsius). They “are so hot that they have some resemblance to being stars even though they’re planets,” Kevin Heng, an astrophysicist at the University of Bern in Switzerland who participated in the study, told Space.com. KELT-9b can reach temperatures of up to 7,800 degrees F (4,300 degrees C).

This record-breaking heat enabled astronomers to detect iron and titanium in KELT-9b’s atmosphere. While researchers have long suspected that these elements are present on some exoplanets — iron is one of the most abundant elements in the universe — it’s difficult to detect them in cooler environments because the atoms are mostly “trapped in other molecules,” Heng said. However, KELT-9b is so hot that the clouds don’t condense in its atmosphere, allowing individual atoms of iron and other metals to fly solo.

Titanium has been found previously in the atmosphere’s of other exoplanets, but only as part of a molecule.

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Excavation begins on site for Giant Magellan Telescope

9:05 am

Excavation has begun for the site where the Giant Magellan Telescope (GMT) will be built in Chile.

Using a combination of hydraulic drilling and hammering, the excavation work is expected to take about five months to complete. Excavation is a key step towards the construction of the GMT, which is expected to see first light as early as 2024.

The 25-meter diameter GMT, expected to have a final weight of about 1,600 metric tons, will comprise seven 8.4-meter mirrors supported by a steel telescope structure that will be seated on the concrete pier. It will be housed inside a rotating enclosure that will measure 65 meters (~22 stories) tall and 56 meters wide. As well as working on the enclosure and telescope pier foundations, Conpax will excavate a recess in the summit rock for the lower portion of the mirror coating chamber and foundations for a utility building and tunnel on the summit.

Of the next generation of big telescopes, GMT is the closest to completion.

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No habitable planets for at least one globular cluster

10:17 am

Calculations by astronomers now suggest that the crowded nature of the giant globular cluster Omega Centauri will probably make it impossible for habitable planets to exist there.

In the hunt for habitable exoplanets, Omega Centauri, the largest globular cluster in the Milky Way, seemed like a good place to look. Comprising an estimated 10 million stars, the cluster is nearly 16,000 light years from Earth, making it visible to the naked eye and a relatively close target for observations by the Hubble Space Telescope.

…[T]he cozy nature of stars in Omega Centauri forced the researchers to conclude that [habitable] planetary systems, however compact, cannot exist in the cluster’s core. While our own sun is a comfortable 4.22 light years from its nearest neighbor, the average distance between stars in Omega Centauri’s core is 0.16 light years, meaning they would encounter neighboring stars about once every 1 million years.

“The rate at which stars gravitationally interact with each other would be too high to harbor stable habitable planets,” Deveny said. “Looking at clusters with similar or higher encounter rates to Omega Centauri’s could lead to the same conclusion. So, studying globular clusters with lower encounter rates might lead to a higher probability of finding stable habitable planets.”

Science thus concludes that Isaac Asimov’s classic science fiction short story, Nightfall, is unlikely.

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Computer simulations suggest solar system was partly shaped by star flyby

9:29 am

The uncertainty of science: New computer simulations now suggest that the solar systems outer regions were shaped by the near approach of another sun-like star billions of years ago.

Susanne Pfalzner and her co-workers suggest that a star was approaching the Sun at an early stage, ‘stealing’ most of the outer material from the Sun’s protoplanetary disk and throwing what was left over into inclined and eccentric orbits. Performing thousands of computer simulations they checked what would happen when a star passes very close-by and perturbs the once larger disk. It turned out that the best fit for today’s outer solar systems comes from a perturbing star which had the same mass as the Sun or somewhat lighter (0.5-1 solar masses) and flew past at approximately 3 times the distance of Neptune.

However, the most surprising thing for the researchers was that a fly-by does not only explain the strange orbits of the objects of the outer solar system, but also gives a natural explanation for several unexplained features of our Solar System, including the mass ratio between Neptune and Uranus, and the existence of two distinct populations of Kuiper Belt objects.

An intriguing result, but to put it mildly it carries a great deal of uncertainty. If true, however, it suggests — as does other research — that our solar system might be somewhat unique. The other research into the solar system’s history suggests we have been traveling through galactic quiet regions for a long time, which helped make things more friendly for the development of life. Together all this work says that in the beginning the solar system was in crowded regions, with its later history then drifting into empty regions.

Thus, the history of our solar system within the galaxy might play a very important part in why we are here.

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Perseid meteor shower this weekend

10:24 am

The annual Perseid meteor shower upcoming on August 12 is expected to be especially good this year because there will be no moon in the sky.

The Perseid meteors seem to come from a single point, the `radiant’, situated in the constellation Perseus, giving the shower its name. This is however just an effect of perspective, as the meteors move parallel to each other, much like drivers see when driving in heavy rain.

The radiant will be visible from around 10pm and at this time there will be the highest chance of seeing `Earth grazing meteors’. These are meteors that skim the Earth’s atmosphere and so have long, blazing tails.

Observers can expect to see a few tens of meteors per hour, or one every few minutes, once darkness has fallen on 12 August. The number of meteors will peak in the early hours of 13 August, when up to around seventy each hour should be visible.

It is worth it to find a nice dark place and stay up all night at least once in your life to watch this shower. Get a nice camp chair that allows you to lie back, make sure you are dressed comfortably, and sit back and enjoy.

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Tess captures comet, variable stars, asteroids, and Martian light

8:44 am

During its testing period prior to beginning science operations this month, the exoplanet space telescope TESS spotted in one series of images a comet, a host of variable stars, some asteroids, and even the faint hint of some reflected light from Mars.

Over the course of these tests, TESS took images of C/2018 N1, a comet discovered by NASA’s Near-Earth Object Wide-field Infrared Survey Explorer (NEOWISE) satellite on June 29. The comet, located about 29 million miles (48 million kilometers) from Earth in the southern constellation Piscis Austrinus, is seen to move across the frame from right to left as it orbits the Sun. The comet’s tail, which consists of gases carried away from the comet by an outflow from the Sun called the solar wind, extends to the top of the frame and gradually pivots as the comet glides across the field of view.

In addition to the comet, the images reveal a treasure trove of other astronomical activity. The stars appear to shift between white and black as a result of image processing. The shift also highlights variable stars — which change brightness either as a result of pulsation, rapid rotation, or by eclipsing binary neighbors. Asteroids in our solar system appear as small white dots moving across the field of view. Towards the end of the video, one can see a faint broad arc of light moving across the middle section of the frame from left to right. This is stray light from Mars, which is located outside the frame. The images were taken when Mars was at its brightest near opposition, or its closest distance, to Earth.

The video that was compiled from these images is embedded below the fold.
» Read more

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Rogue giant exoplanet or brown dwarf discovered about 20 light years away

5:16 pm

Using the Jansky VLA radio telescope astronomers have detected evidence of rogue giant exoplanet or brown dwarf about 20 light years away

Astronomers using the National Science Foundation’s Karl G. Jansky Very Large Array (VLA) have made the first radio-telescope detection of a planetary-mass object beyond our Solar System. The object, about a dozen times more massive than Jupiter, is a surprisingly strong magnetic powerhouse and a “rogue,” traveling through space unaccompanied by any parent star.

“This object is right at the boundary between a planet and a brown dwarf, or ‘failed star,’ and is giving us some surprises that can potentially help us understand magnetic processes on both stars and planets,” said Melodie Kao, who led this study while a graduate student at Caltech, and is now a Hubble Postdoctoral Fellow at Arizona State University.

The data is not sufficient yet to determine whether this is an exoplanet or a brown dwarf. It is big, and it is floating independent of any other objects, which makes it interesting in of itself.

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Astronomers discover 10 more Jupiter moons

9:48 am

Worlds without end: Astronomers, while searching for objects in the Kuiper Belt, have discovered 10 more Jupiter moons.

All the newfound moons are small, between about 1 and 3 kilometres across. Seven of them travel in remote orbits more than 20 million kilometres away from Jupiter, and in the opposite direction from the planet’s rotation. That puts them in the category known as retrograde moons.

The eighth moon stands out because it travels in the same region of space as the retrograde moons, but in the opposite direction (that is, in the same direction as Jupiter’s spin). Its orbit is also tilted with respect to those of the retrograde moons. That means it could easily smash into the retrograde moons, pulverizing itself into oblivion. It may be the leftovers of a bigger cosmic collision in the past, Sheppard says.

Jupiter’s moons are named after gods with connections to the mythological Jupiter or Zeus. Sheppard has proposed naming the oddball Valetudo, after one of Jupiter’s descendants, the Roman goddess of hygiene and health.

The ninth and tenth newfound moons orbit closer to Jupiter, moving in the same direction as the planet.

I predict that these are not the last moons of Jupiter to be discovered. As our observing skills improve, more are certain to pop up.

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Binary asteroid imaged by radio telescopes

10:18 am

Three radio telescopes have successfully imaged the rotation of a binary asteroid, the fourth such binary so far discovered.

On June 21, the asteroid 2017 YE5 made its closest approach to Earth for at least the next 170 years, coming to within 3.7 million miles (6 million kilometers) of Earth, or about 16 times the distance between Earth and the Moon. On June 21 and 22, observations by NASA’s Goldstone Solar System Radar (GSSR) in California showed the first signs that 2017 YE5 could be a binary system. The observations revealed two distinct lobes, but the asteroid’s orientation was such that scientists could not see if the two bodies were separate or joined. Eventually, the two objects rotated to expose a distinct gap between them.

Scientists at the Arecibo Observatory in Puerto Rico had already planned to observe 2017 YE5, and they were alerted by their colleagues at Goldstone of the asteroid’s unique properties. On June 24, the scientists teamed up with researchers at the Green Bank Observatory (GBO) in West Virginia and used the two observatories together in a bi-static radar configuration (in which Arecibo transmits the radar signal and Green Bank receives the return signal). Together, they were able to confirm that 2017 YE5 consists of two separated objects. By June 26, both Goldstone and Arecibo had independently confirmed the asteroid’s binary nature.

The new observations obtained between June 21 and 26 indicate that the two objects revolve around each other once every 20 to 24 hours. This was confirmed with visible-light observations of brightness variations by Brian Warner at the Center for Solar System Studies in Rancho Cucamonga, California.

I have embedded below the fold a short video that includes the radio images showing this rotation. Most cool!
» Read more

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Astronomers track neutrino from galaxy 3.7 billion light years away

10:04 am

Using multiple telescopes astronomers have successfully tracked the source of a neutrino that was detected on September 22 2017 by the IceCube neutrino telescope in Antarctica to a galaxy 3.7 billion light years away.

Because scientists on the IceCube experiment had worked out the path the particle took through their subterranean ice instrument, astronomers knew where in the sky to look for the particle’s source. A string of early observations came up blank, but days later Nasa’s Fermi Gamma-ray Space Telescope spotted the likely source: a flaring “blazar”.

Most galaxies are thought to have spinning supermassive black holes at their centres. But some of these black holes appear to pull in material at ferocious rates, a process that simultaneously sends streams of highly energetic particles out into space. Such galaxies are called blazars, although the term only applies when one of these streams is directed straight at Earth.

The blazar that appears to have sent the neutrino our way lies 3.7bn light years from Earth, just off the left shoulder of the constellation of Orion. While a single detection is not strong evidence, the IceCube scientists went back through their records and found a flurry of neutrinos coming from the same spot over 150 days in 2014 and 2015.

This I think is the first time scientists have linked a neutrino to its source, outside our solar system. Most neutrino detections come from the Sun. That they could trace this one back to a blazar so far away means their neutrino telescopes are now becoming sensitive enough to find and study the neutrinos coming from other sources.

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Conflict in Hubble constant increases with new data from Hubble and Gaia

8:52 am

The uncertainty of science: New data from the Hubble Space Telescope and Gaia continues to measure a different Hubble constant for the expansion rate of the universe, when compared with data from the Planck space telescope.

Using Hubble and newly released data from Gaia, Riess’ team measured the present rate of expansion to be 73.5 kilometers (45.6 miles) per second per megaparsec. This means that for every 3.3 million light-years farther away a galaxy is from us, it appears to be moving 73.5 kilometers per second faster. However, the Planck results predict the universe should be expanding today at only 67.0 kilometers (41.6 miles) per second per megaparsec. As the teams’ measurements have become more and more precise, the chasm between them has continued to widen, and is now about 4 times the size of their combined uncertainty.

The problem really is very simple: We haven’t the faintest idea what is going on. We have some data, but we also have enormous gaps in our knowledge of the cosmos. Moreover, most of our cosmological data is reliant on too many assumptions that could be wrong, or simply in error. And the errors can be tiny and still throw the results off by large amounts.

The one thing that good science and skepticism teaches is humbleness. Do not be too sure of your conclusions. The universe is a large and complex place. It likes to throw curve balls at us, and if we swing too soon we will certainly miss.

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Astronomers dispute existence of galaxy without dark matter

10:40 am

The uncertainty of science: A new analysis by astronomers disputes the conclusion of different astronomers earlier this year that they had found a galaxy that lacked any dark matter.

The original paper from March based its stunning claim of a dark-matter-free galaxy on the way clusters of stars moved through the thin, diffuse galaxy called NGC1052–DF2: They appeared to move at exactly the speed Einstein’s equations of general relativity would predict based on the visible matter (so, slower than they would if the galaxy held dark matter).

This new paper on arXiv suggested otherwise: First, the authors pointed out that NGC1052–DF2 was already discovered way back in 1976 and has previously been referred to by three different names: KKSG04, PGC3097693 and [KKS2000]04.

Then, using those names and then finding all the available data on the galaxy, the researchers argued that the researchers from the March paper simply mismeasured the distance between that galaxy and Earth. This means the galaxy is probably much closer to us than the original researchers thought.

Astronomers calculate the mass of galaxies based on the objects’ brightness and distance. If the galaxy examined in the paper is closer to Earth than previously thought, then its dimness means it’s also much less massive than researchers thought. And at the newly calculated, lighter mass, all the other features of the galaxy make a lot more sense, the researchers in the new paper said. Its globular clusters aren’t moving slowly because they’re in some strange dark matter-desert; instead, they’re moving at the regular speed for a very lightweight galaxy, the arXiv authors said.

To put it bluntly, the astronomers don’t have enough solid data to decide this issue one way or the other. Moreover, the dispute indicates once again that the whole dark matter theory itself is based on very limited data with large margins of error. It might be the best theory we’ve got to explain the data we have, but no good scientist takes it too seriously. We just don’t know enough yet.

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Searchers find fragment of asteroid that hit Earth June 2nd

10:00 am

Researchers and local park volunteers in Botswana’s Central Kalahari Game Reserve on July 8 announced the discovery of a fragment from an asteroid that hit the Earth June 2 only eight hours after it was discovered.

“The biggest uncertainty we faced was to determine where exactly the meteorites fell,” says Peter Jenniskens a subject expert of the SETI Institute in California, who traveled to Botswana to assist in the search. He teamed up with Oliver Moses of the University of Botswana’s Okavango Research Institute (ORI), to gather security surveillance videos in Rakops and Maun to get better constraints on the position and altitude of the fireball’s explosion. Team member Tim Cooper of the Astronomical Society of Southern Africa calibrated videos to the south.

After disruption, the asteroid fragments scattered over a wide area, blown by the wind while falling down. Calculations of the landing area were done independently by the NASA-sponsored group headed by Jenniskens, as well as by Esko Lyytinen and Jarmo Moilanen of the Finnish Fireball Network. These calculations were defining the fall area well enough to warrant the deployment of a search expedition.

The first meteorite was found after five days of walking and scouring a landscape of sand, thick tall grass, shrubs and thorn bushes by a team of geoscientists from the Botswana International University of Science and Technology (BUIST), the Botswana Geoscience Institute (BGI) and from ORI, guided by Jenniskens. The Botswana Department of Wildlife and National Parks granted access and deployed their park rangers to provide protection and participate in the search. BUIST student Lesedi Seitshiro was first to spot the stone.

This is only the second time in history that a small asteroid observed in space was recovered following its impact on Earth.

I have amateur astronomer friends who attempted to do this exact thing, here in Tucson. We actually went out one day hunting for a meteorite they had tracked, but were unsuccessful in finding anything. To have had success we would have likely required more search time and a better constraint on the asteroid’s landing zone.

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Galaxies collide!

7:07 am

Using data from then space telescope Gaia, astronomers have identified evidence that 8 to 10 billion years ago the Milky Way collided with a dwarf galaxy.

The astronomers propose that around 8 billion to 10 billion years ago, an unknown dwarf galaxy smashed into our own Milky Way. The dwarf did not survive the impact: It quickly fell apart, and the wreckage is now all around us.

“The collision ripped the dwarf to shreds, leaving its stars moving in very radial orbits” that are long and narrow like needles, said Vasily Belokurov of the University of Cambridge and the Center for Computational Astrophysics at the Flatiron Institute in New York City. The stars’ paths take them “very close to the center of our galaxy. This is a telltale sign that the dwarf galaxy came in on a really eccentric orbit and its fate was sealed.”

It is thought that this dwarf galaxy was quite large for a dwarf galaxy.

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A star that shoots cosmic rays

7:02 am

New data from the space telescope NuSTAR suggests that the giant star Eta Carina, expected to be a supernova sometime in the future, emits cosmic rays, some of which reach the Earth.

The cosmic rays are produced by shock waves resulting from the clash between the intense solar winds of the system’s two stars.

Go to the link to see a truly beautiful image of this star system. You will immediately see that it is a system exploding.

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James Webb Space Telescope delayed again, with budget rising

11:30 am

Based the conclusions [pdf] of an Independent Review Board (IRB), NASA has once again delayed the launch of the James Webb Space Telescope, now set for 2021, while increasing its construction budget from $8 billion to almost $9 billion.

In its report, the IRB found that technical issues, including human errors, have greatly impacted the development schedule.

The agency previously had estimated an earlier launch date, but awaited findings from the IRB before making a final determination and considered data from Webb’s Standing Review Board. The agency established the new launch date estimate [March 30, 2021] to accommodate changes in the schedule due to environmental testing and work performance challenges by Northrop Grumman on the spacecraft’s sunshield and propulsion system. The telescope’s new total lifecycle cost, to support the revised launch date, is estimated at $9.66 billion; its new development cost estimate is $8.8 billion.

It is important to remember that Webb was originally supposed to cost $1 billion, and launch in 2011. It is now a decade behind schedule, with a cost almost ten times higher.

It really does appear like SLS and Webb are in a race to see who can get launched last. And right now, the race is neck and neck.

I should add that if the launch gets delayed much more, NASA will have further problems with the launch rocket. The Ariane 5 rocket, designated as the launch vehicle, is being retired around 2021. Beyond that date there might be problems using one.

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New observations of interstellar Oumuamua give it comet-like properties

11:10 am

The uncertainty of science: New observations of interstellar object Oumuamua suggest that it is a comet, not an asteroid.

[B]y combining data from the NASA/ESA Hubble Space Telescope, the Canada-France-Hawaii Telescope, ESO’s Very Large Telescope and the Gemini South Telescope, an international team of astronomers has found that the object is moving faster than predicted. The measured gain in speed is tiny and `Oumuamua is still slowing down because of the pull of the Sun — just not as fast as predicted by celestial mechanics.

The team, led by Marco Micheli (European Space Agency) explored several scenarios to explain the faster-than-predicted speed of this peculiar interstellar visitor. The most likely explanation is that `Oumuamua is venting material from its surface due to solar heating — a behaviour known as outgassing. The thrust from this ejected material is thought to provide the small but steady push that is sending `Oumuamua hurtling out of the Solar System faster than expected — as of 1 June, it is travelling with about 114 000 kilometres per hour.

Such outgassing is a typical behaviour for comets and contradicts the previous classification of `Oumuamua as an interstellar asteroid. “We think this is a tiny, weird comet,” comments Marco Micheli. “We can see in the data that its boost is getting smaller the farther away it travels from the Sun, which is typical for comets.”

If I was to speculate wildly, I could also wonder if maybe the aliens on board have decided they needed to get the heck out of here as fast as possible, and have fired their thrusters to make that happen.

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Grease in space

9:16 am

Based on observed data and lab recreations, astronomers have found that much of the galaxy’s interstellar dust is made of grease-like carbon molecules.

Organic matter of different kinds contains carbon, an element considered essential for life. There is though real uncertainty over its abundance, and only half the carbon expected is found between the stars in its pure form. The rest is chemically bound in two main forms, grease-like (aliphatic) and mothball-like (aromatic).

The UNSW / Ege team used a laboratory to create material with the same properties as interstellar dust. They mimicked the process by which organic molecules are synthesised in the outflows of carbon stars, by expanding a carbon-containing plasma into a vacuum at low temperature. The material was collected and then analysed by a combination of techniques. Using magnetic resonance and spectroscopy (splitting light into its constituent wavelengths) they were able to determine how strongly the material absorbed light with a certain infrared wavelength, a marker for aliphatic carbon.

“Combining our lab results with observations from astronomical observatories allows us to measure the amount of aliphatic carbon between us and the stars”, explained Professor Tim Schmidt, from the Australian Research Council Centre of Excellence in Exciton Science in the School of Chemistry at UNSW Sydney.

The researchers found that there are about 100 greasy carbon atoms for every million hydrogen atoms, accounting for between a quarter and a half of the available carbon. In the Milky Way Galaxy, this amounts to about 10 billion trillion trillion tonnes of greasy matter, or enough for 40 trillion trillion trillion packs of butter.

I guarantee that these results have a large margin of error. I also guarantee that they contain a significant element of truth.

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Hawaii’s Supreme Court to review TMT’s permit, again

8:36 am

Hawaii’s Supreme Court is set to review, for the second time, the construction permit for the Thirty Meter Telescope.

Much of the arguments centered around whether it was a conflict of interest for a hearings officer who made a key recommendation in favor of the project to be a member of a Hawaii astronomy center. The state allowed retired judge Riki May Amano to preside over contested-case hearings for the contentious project despite complaints from telescope opponents who decried her paid membership to the Imiloa Astronomy Center.

The Big Island center is connected to the University of Hawaii, which is the permit applicant.

Opponents appealed to the Supreme Court after Amano recommended granting the permit and the state land board approved it. “She should have never presided over the case,” Richard Wurdeman, an attorney representing telescope opponents, told the justices. He noted the center included exhibits about the project planned for the Big Island’s Mauna Kea, Hawaii’s tallest mountain.

The details don’t really matter. Nor will the decision. The protesters will simply find another petty issue if they lose, and will appeal again. Their goal, apparently supported covertly by Hawaii’s Democratic government, is to delay, delay, and delay, until the consortium building TMT is forced to abandon Hawaii.

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The mysterious dust surrounding Tabby’s Star

8:44 am

New studies of Tabby’s Star suggest that the dust clouds that cause it to fluctuate in brightness in apparently random ways are unusual and baffling in their own right.

[I]t appears that the dimming of Tabby’s star comes not from large objects such as swarms of asteroids, comets, or alien solar collectors, but from drifting bands of dust particles. But like any good mystery, it’s not quite that simple.

Each of the four dimming events observed in 2017 affected red and blue light differently, suggesting that they involved dust particles of different sizes. And the long-term brightness changes appear to be associated with much larger grains. “So the dust cloud is extremely complex,” Bodman says. “Each dip is a different kind of dust … What we’re seeing is different parts of the [dust] cloud as they pass in front of the star.”

A first guess, probably wrong, is that the four dimming events were caused by dust streams orbiting the star at different distances, each a different patchy ring around the star made up of slightly different materials.

And if you accept my guess as right, I also have bridge in Brooklyn I want to sell you. Real cheap too!

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More Earthlike exoplanets!

9:13 am

Astronomers using data from Kepler have discovered two stars, both with multiple orbiting Earth-sized planets. One has three planets all almost exactly the mass of Earth.

The first exoplanetary system is located in the star K2-239, characterized by these researchers as a red dwarf type M3V from observations made with the Gran Telescopio Canarias (GTC), at the Roque de los Muchachos Observatory (Garafía, La Palma). It is located in the constellation of the Sextant at 50 parsecs from the Sun (at about 160 light years). It has a compact system of at least three rocky planets of similar size to the Earth (1.1, 1.0 and 1.1 Earth radii) that orbit the star every 5.2, 7.8 and 10.1 days, respectively.

The other red dwarf star called K2-240 has two super-Earth-like planets about twice the size of our planet. Although the atmospheric temperature of red dwarf stars, around which these planets revolve, is 3,450 and 3,800 K respectively, almost half the temperature of our Sun, these researchers estimate that all planets discovered will have temperatures superficial tens of degrees higher than those of the planet Earth due to the strong radiation they receive in these close orbits to their stars.

Knowing more about the surface environments of these very Earthlike exoplanets, as hostile as they might be to life, would teach us a great deal about our own planet and its birth and evolution.

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More problems for James Webb Space Telescope?

9:45 am

The impending release of an independent NASA review of the state of the James Webb Space Telescope project suggests that the project is faced with additional issues.

NASA is in the process of evaluating the report from the Independent Review Board chaired by Tom Young to assess the status of the James Webb Space Telescope (JWST). Established in March, the Board was due to submit its report on May 31. NASA said today that the Board has completed its work and briefed NASA. The report will be released later this month after NASA determines the impact on cost and schedule.

Thomas Zurbuchen, NASA Associate Administrator for the Science Mission Directorate, created the Webb Independent Review Board (WIRB) on March 27, the same day he announced another delay in the telescope’s launch. WIRB held its first meeting the next week.

For many years, JWST appeared to be on track for launch in October 2018 after a 2011 restructuring that followed a series of earlier cost overruns and schedule delays. Congress capped the development cost (not operations) at $8 billion in law. Pursuant to the 2005 NASA Authorization Act, if a program exceeds 30 percent of its baseline estimated cost, NASA must notify Congress and no money may be spent on it after 18 months from the time of that notification unless Congress reauthorizes it.

The project will not die, Congress will simply extend it with lots more money. That is how big NASA projects really function, to take as long as possible so that they can continue their real goal of providing pork barrel jobs in congressional districts.

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No giant planet needed in Kuiper Belt to shape orbits of outer known planets

9:27 am

Using computer models astronomers have found that the tiny objects in the Kuiper Belt could be sufficient, instead of one giant undiscovered planet, to provide the gravity necessary to explain the orbits of the solar system’s outer planets.

They call theorized giant planet “Planet Nine,” which seems silly since Pluto really still fills that role. Nonetheless, this work also might explain the process that flung some surprisingly large objects so far out into the Kuiper Belt.

They ran supercomputer simulations of how bodies might interact in the outer Solar System far beyond Pluto, in the icy region known as the Kuiper belt. They found that a flock of Moon-sized worlds could do many of the same things as Planet Nine.

Over millions of years, the collective gravity of these smaller worlds would nudge the orbits of distant objects. The worlds would jostle one another like bumper cars and, occasionally, cause an object to move into a very distant orbit. Their simulations suggest that more-massive objects would be flung into the most distant orbits — as some observations have suggested.

We must also remind ourselves that this conclusion is based on a computer model, and is filled with uncertainty. We also do not yet have a full census of objects in the Kuiper Belt, which means this model required many assumptions.

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