Tag Archives: astronomy

Giant planets around young star defy model predictions

The uncertainty of science: The recent discovery of four Saturn/Jupiter-sized planets orbiting a star only about two million years old throws a wrench into all existing solar system formation theories.

The star, CI Tau, is located about 500 light years away in a highly-productive stellar ‘nursery’ region of the galaxy. Its four planets differ greatly in their orbits: the closest (the hot Jupiter) is within the equivalent of the orbit of Mercury, while the farthest orbits at a distance more than three times greater than that of Neptune. The two outer planets are about the mass of Saturn, while the two inner planets are respectively around one and 10 times the mass of Jupiter.

The discovery raises many questions for astronomers. Around 1% of stars host hot Jupiters, but most of the known hot Jupiters are hundreds of times older than CI Tau. “It is currently impossible to say whether the extreme planetary architecture seen in CI Tau is common in hot Jupiter systems because the way that these sibling planets were detected – through their effect on the protoplanetary disc – would not work in older systems which no longer have a protoplanetary disc,” said Professor Cathie Clarke from Cambridge’s Institute of Astronomy, the study’s first author.

According to the researchers, it is also unclear whether the sibling planets played a role in driving the innermost planet into its ultra-close orbit, and whether this is a mechanism that works in making hot Jupiters in general. And a further mystery is how the outer two planets formed at all.

“Planet formation models tend to focus on being able to make the types of planets that have been observed already, so new discoveries don’t necessarily fit the models,” said Clarke. “Saturn mass planets are supposed to form by first accumulating a solid core and then pulling in a layer of gas on top, but these processes are supposed to be very slow at large distances from the star. Most models will struggle to make planets of this mass at this distance.” [emphasis mine]

In other words, the present models are absurdly premature. We simply don’t know enough to formulate any theory that can be taken seriously.

This is not to say that models shouldn’t be formulated, only to emphasize that no one should consider them predictive of any part of reality. They give astronomers some guidance on what to look for, but if they take them too seriously they might not look in the right places.

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Chandra goes into safe mode

When it rains it pours: The Chandra X-ray Observatory went into into safe mode on October 10 for reasons that are either not yet understood or have not yet been revealed.

Chandra, Spitzer, and Hubble are the three remaining of the original four great observatories proposed in the late 1980s, with the Compton Gamma-Ray Observatory the fourth. Compton was de-orbited in 2000. Spitzer’s infrared observational capabilities became limited when its cryogenic cooling gas became exhaused in 2009.

Hubble and now Chandra are both in safe mode, leaving astronomy badly crippled.

This situation is actually the fault of the astronomical community, which in the early 2000s put all its money behind the James Webb Space Telescope, leaving little for the construction of replacement space telescopes for either Hubble or Chandra. In addition, the astronomical community has continued to put is money behind similar big, expensive, and giant projects like Webb, pushing for WFIRST with its 2011 decadal survey. Like Webb, WFIRST will cost billions and take almost a decade to build and launch, assuming there are no delays.

Meanwhile, the workhorses in orbit are failing one by one.

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Update on Hubble: no real news

NASA today released an update on the effort to bring the Hubble Space Telescope out of safe mode and back to full operation.

The only new information they really provide is what they will do, depending on whether they can fix the back up gyroscope or not.

If the team is successful in solving the problem, Hubble will return to normal, three-gyro operations. If it is not, the spacecraft will be configured for one-gyro operations, which will still provide excellent science well into the 2020s, enabling it to work alongside the James Webb Space Telescope and continue groundbreaking science.

In other words, if they cannot find a way to get this third gyro functioning properly, they will shut down one of the two remaining working gyros so that it can operate as a backup, and operate the telescope on one gyroscope.

I find the last section of the quote above very amusing, in a dark sort of way. Not only does NASA rationalize the sad loss of Hubble’s ability to take sharp images, it tries to rationalize the decade-long delays it has experienced building the James Webb Space Telescope. Webb was supposed to have been launched in 2011. It should have been up there already, working alongside Hubble for the past seven years.

Now, the best we can hope for is that Webb will finally reach space while Hubble is still functioning, in a crippled condition. I would not be surprised however if Webb is further delayed, and Hubble is gone before it gets into space.

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Astronomers double the number of known fast radio bursts

Using a radio telescope in Australia astronomers have now doubled the number of known fast radio bursts.

Fast radio bursts come from all over the sky and last for just milliseconds. Scientists don’t know what causes them but it must involve incredible energy—equivalent to the amount released by the Sun in 80 years.

“We’ve found 20 fast radio bursts in a year, almost doubling the number detected worldwide since they were discovered in 2007,” said lead author Dr Ryan Shannon, from Swinburne University of Technology and the OzGrav ARC Centre of Excellence.

In other words, only forty bursts total have ever been detected. The data here however suggests that the bursts are coming from very far away and from the early universe, information which will help scientists figure out what is causing them.

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Hubble in safe mode, down to two gyroscopes

The end might be near: The Hubble Space Telescope went into safe mode this weekend when one of its three working gyroscopes failed.

Hubble has six gyroscopes, all of which were replaced by spacewalking astronauts during a servicing mission in May 2009. The telescope needs three working gyroscopes to “ensure optimal efficiency,” mission team members have written, and the failure brings that number down to two (if the “problematic” one that had been off can’t be brought back online).

But that doesn’t mean it’s time to panic. Hubble can do good science with two gyroscopes, or even one, astrophysicist Grant Tremblay, of the Harvard-Smithsonian Center for Astrophysics, said via Twitter Sunday.

While it is true that Hubble can do science on one or two gyroscopes, in that mode it will no longer be able to take the sharp spectacular pictures that represent its great glory.

Hubble was launched in 1990, fixed in 1993, and has been the most successful science robot ever launched. Scientists had hoped, when they made the James Webb Space Telescope their priority in the very early 2000s that both would be in space and operating to provide top notch science data, with Hubble working in visible wavelengths and Webb in the infrared. Webb’s endless delays and cost overruns has now probably made that impossible.

Worse, there are no plans to build a replacement for Hubble. For the first time since 1993, the human race will no longer be able to see, with our own eyes, the universe sharply.

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Data from Voyager 2 suggests it is entering interstellar space

New data since August from Voyager 2 now suggests it is finally leaving the heliosphere of the solar system and entering interstellar space.

Since late August, the Cosmic Ray Subsystem instrument on Voyager 2 has measured about a 5 percent increase in the rate of cosmic rays hitting the spacecraft compared to early August. The probe’s Low-Energy Charged Particle instrument has detected a similar increase in higher-energy cosmic rays.

Cosmic rays are fast-moving particles that originate outside the solar system. Some of these cosmic rays are blocked by the heliosphere, so mission planners expect that Voyager 2 will measure an increase in the rate of cosmic rays as it approaches and crosses the boundary of the heliosphere.

In May 2012, Voyager 1 experienced an increase in the rate of cosmic rays similar to what Voyager 2 is now detecting. That was about three months before Voyager 1 crossed the heliopause and entered interstellar space.

The scientists warn that there is great uncertainty here, and that the actual transition into interstellar space might take longer than with Voyager 1 since Voyager 2 is traveling in a different direction and is leaving during a different time in the solar cycle.

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The first exomoon found?

Worlds without end: Scientists using data from the Hubble Space Telescope and Kepler have detected evidence that suggests the discovery of the first moon outside our solar system.

The data indicate an exomoon the size of Neptune, in a stellar system 8000 light-years from Earth. The new results are presented in the journal Science Advances.

…In 2017 NASA’s Kepler Space Telescope detected hints of an exomoon orbiting the planet Kepler-1625b. Now, two scientists from Columbia University in New York (USA) have used the incomparable capabilities of the NASA/ESA Hubble Space Telescope to study the star Kepler-1625, 8000 light-years away, and its planet in more detail. The new observations made with Hubble show compelling evidence for a large exomoon orbiting the only known planet of Kepler-1625. If confirmed, this would be the first discovery of a moon outside our Solar System.

The candidate moon, with the designation Kepler-1625b-i, is unusual because of its large size; it is comparable in diameter to the planet Neptune. Such gargantuan moons are unknown in our own Solar System. “This may yield new insights into the development of planetary systems and may cause astronomers to revisit theories of how moons form,” Alex Teachey, a graduate student who led the study, explained excitedly.

Like its moon, Kepler-1625b is also bigger than its counterparts in the Solar System. The exoplanet is a gas giant, several times more massive than Jupiter. It orbits its parent star at a distance similar to the distance between the Sun and Earth, which puts it — and its candidate moon — at the inner edge of the habitable zone of the star system.

The alien nature of this solar system should not surprise us. If anything, it is only a hint at the wild and exotic solar systems we have yet to discover.

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Astronomers discover very distant object orbiting the Sun

Astronomers have discovered a very distant object in a solar orbit ranging from 6 billion to 213 billion miles from the Sun.

Designated 2015 TG387 and nicknamed “The Goblin” by its discoverers, this object resides in the inner Oort Cloud, a region beyond the Kuiper Belt that until now harbored only two other known bodies: the dwarf planet Sedna and the less well-known 2012 VP113.

The scientists estimate its size to be about 200 miles in diameter. Based on the existence of the three known objects in this region of space, the scientists estimate there could be as many as 2 million objects there bigger than 25 miles in diameter. There is a lot of uncertainty in that number.

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More intergalactic stars discovered

Worlds without end: Using the data from Gaia’s second data release astronomers have identified twenty stars that are moving too fast to be permanent members of the Milky Way galaxy.

More significantly, most appeared to be approaching the galaxy, not flying away from it, suggesting they are visitors from other galaxies.

It is possible that these intergalactic interlopers come from the Large Magellanic Cloud, a relatively small galaxy orbiting the Milky Way, or they may originate from a galaxy even further afield. If that is the case, they carry the imprint of their site of origin, and studying them at much closer distances than their parent galaxy could provide unprecedented information on the nature of stars in another galaxy – similar in a way to studying Martian material brought to our planet by meteorites.

…An alternative explanation is that the newly identified sprinting stars could be native to our Galaxy’s halo, accelerated and pushed inwards through interactions with one of the dwarf galaxies that fell towards the Milky Way during its build-up history. Additional information about the age and composition of the stars could help the astronomers clarify their origin.

At least two more data releases shall come from Gaia, launched by Europe to precisely track the location and motions of a billion stars. So far, they have complete 3D velocity information for about seven million stars. After these additional data releases they expect to have complete 3D velocity information for 150 million stars, and should identify a lot more intergalactic stars at that time.

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Breakthrough Listen adds southern hemisphere telescope to extraterrestrial listening campaign

Breakthrough Listen has added the MeerKAT telescope in South Africa to its extraterrestrial listening campaign, thereby expanding the campaign to cover almost the entire sky.

Breakthrough Listen’s MeerKAT survey will examine a million individual stars – 1,000 times the number of targets in any previous search – in the quietest part of the radio spectrum, monitoring for signs of extraterrestrial technology. With the addition of MeerKAT’s observations to its existing surveys, Listen will operate 24 hours a day, seven days a week, in parallel with other surveys. “Collaborating with MeerKAT will significantly enhance the capabilities of Breakthrough Listen”, said Yuri Milner, founder of the Breakthrough Initiatives. “This is now a truly global project.”

Built and operated by the South African Radio Astronomy Observatory (SARAO), and inaugurated in July 2018, MeerKAT is a powerful array of 64 radio antennas in the remote Karoo Desert of South Africa. By partnering with SARAO, Breakthrough Listen gains access to one of the world’s premier observing facilities at radio wavelengths. Signals from the 64 dishes (each 13.5 meters in diameter) are combined electronically to yield an impressive combination of sensitivity, resolution and field of view on the sky. MeerKAT also serves as a precursor for the Square Kilometre Array, which will expand and enhance the current facility in the coming decades, eventually spanning a million square meters across South Africa and Australia to create by far the world’s largest radio telescope.

They have also widened their approach. They are not simply looking for intelligent radio communications, they are looking for any signs of technology.

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NASA extends Chandra telescope operation to 2024

NASA has extended its contract with the Smithsonian Astrophysical Observatory in Massachusetts to run the Chandra X-ray Observatory through 2024.

In many ways the longevity of both Hubble and Chandra as well as other space telescopes has demonstrated the robustness of much in-space engineering these days. It suggests that when we finally begin building manned interplanetary spaceships we should have confidence they will operate reliably for long periods.

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Four candidate stars identified as home for Oumuamua

The uncertainty of science: Astronomers have identified four stars as possible home stars for the interstellar object Oumuamua.

Bailer-Jones and his colleagues found four stars that are possible candidates for ‘Oumuamua’s home world. All four of them are dwarf stars. The one that came closest to ‘Oumuamua, at least about one million year ago, is the reddish dwarf star HIP 3757. It approached within about 1.96 light-years. Given the uncertainties unaccounted for in this reconstruction, that is close enough for ‘Oumuamua to have originated from its planetary system (if the star has one). However, the comparatively large relative speed (around 25 km/s) makes it less probable for this to be ‘Oumuamua’s home.

The next candidate, HD 292249, is similar to our Sun, was a little bit less close to the object’s trajectory 3.8 million years ago, but with a smaller relative speed of 10 km/s. The two additional candidates met ‘Oumuamua 1.1 and 6.3 million years ago, respectively, at intermediate speeds and distances. These stars have been previously catalogued by other surveys, but little is known about them.

There is much uncertainty here. None of these stars might be Oumuamua’s actual original star, but might have instead shifted its orbit from its past course.

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Historian discovers long-lost original of Galileo letter

An historian doing different research in the library of Great Britain’s Royal Society has accidentally discovered a long-lost original of a letter by Galileo that might clarify the events surrounding his eventual trial with the Inquisition.

The seven-page letter, written to a friend on 21 December 1613 and signed “G.G.”, provides the strongest evidence yet that, at the start of his battle with the religious authorities, Galileo actively engaged in damage control and tried to spread a toned-down version of his claims.

The question that has been bothering historians for hundreds of years is whether the letter, used as evidence against Galileo during his inquisition trail, was doctored by the inquisition or Galileo. During the trial Galileo presented a milder version that he claimed was the original. This original, with corrections in Galileo’s hand, suggests it was he that did the rewrite.

The story of how postdoctoral student from Italy, Salvatore Ricciardo, found it in a British library however is as interesting:

Ricciardo uncovered the document when he was spending a month this summer touring British libraries to study any handwritten comments that readers might have left on Galileo’s printed works. When his one day at the Royal Society was finished, he idly flicked through the online catalogue looking for anything to do with Castelli, whose writings he had recently finished editing.

One entry jumped out at him — a letter that Galileo wrote to Castelli. According to the catalogue, it was dated 21 October 1613. When Ricciardo examined it, his heart leapt. It appeared to include Galileo’s own signature, “G.G.”; was actually dated 21 December 1613; and contained many crossings out. He immediately realized the letter’s potential importance and asked for permission to photograph all seven pages.

“Strange as it might seem, it has gone unnoticed for centuries, as if it were transparent,” says Giudice [Ricciardo’s doctoral supervisor]. The misdating might be one reason that the letter has been overlooked by Galileo scholars, says Giudice. The letter was included in an 1840 Royal Society catalogue — but was also misdated there, as 21 December 1618.Another reason might be that the Royal Society is not the go-to place in the United Kingdom for this type of historical document, whose more natural home would have been the British Library.

The historians are now trying to trace how long the letter has been in the Royal Society library, and how it arrived there. They know that it has been there since at least the mid-eighteenth century, and they have found hints in old catalogues that it might even have been there a century or more earlier. The researchers speculate that it might have arrived at the society thanks to close connections between the Royal Society and the Academy of Experiments in Florence, which was founded in 1657 by Galileo’s students but fizzled out within a decade or so.

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More details about Sunspot Observatory closure confirms child porn investigation

News stories this morning provide further confirmation that the closure of the Sunspot Observatory in New Mexico occurred in connection with a child porn investigation. The key quote that explains why the FBI closed the facility:

The search warrant provided to a judge the justifications for agents to search computers, cellphones or tablets owned by the janitor, Joshua Lee Cope, and the house trailer where he lives. An FBI agent seized the laptop at the observatory on Aug. 21, 2018, and took it to the FBI office in Las Cruces, court documents said. FBI spokesman Frank Fisher said Thursday that no one has been charged and the investigation is ongoing.

Cope, 30, lives on property owned by his parents in La Luz, the search warrant said. A phone message left for Cope at a telephone number listed for his parents seeking comment was not immediately returned.

After Cope could not find his laptop, the court documents said, he began to act frantically and told the chief observer that there was a “serial killer in the area, and that he was fearful that the killer might enter the facility and execute someone.”

The observatory closed, without consulting FBI agents, after Cope’s comments about the serial killer and his erratic behavior, the warrant said.

My guess is that the observatory became concerned about Cope’s behavior, and closed to protect itself and its other employees, forcing everyone to leave. This also explains the cryptic nature of their closure announcement, as they also did not want to implicate anyone and risk a lawsuit.

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Astronomers detect matter falling into black hole at 30% of the speed of light

Using the XMM-Newton X-ray space telescope astronomers have detected matter falling into the central supermassive black hole at 30% of the speed of light in a galaxy a billion light years away.

Using data from XMM-Newton, Prof. Pounds and his collaborators looked at X-ray spectra (where X-rays are dispersed by wavelength) from the galaxy PG211+143. This object lies more than one billion light years away in the direction of the constellation Coma Berenices, and is a Seyfert galaxy, characterised by a very bright AGN [active galactic nucleus] resulting from the presence of the massive black hole at its nucleus.

The researchers found the spectra to be strongly red-shifted, showing the observed matter to be falling into the black hole at the enormous speed of 30 per cent of the speed of light, or around 100,000 kilometres per second. The gas has almost no rotation around the hole, and is detected extremely close to it in astronomical terms, at a distance of only 20 times the hole’s size (its event horizon, the boundary of the region where escape is no longer possible).

Astronomers have theorized for several decades that the reason Seyfert galaxies have such active nuclei is exactly because matter is falling into the central black hole. This observation appears to confirm that theory.

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Sunspot observatory shut down for child porn investigation?

According to one New Mexico television station, the Sunspot Observatory was shut down last week in connection with a investigation into child porn.

A federal search warrant reveals that Sunspot Solar Observatory was shut down as FBI agents conducted computer forensic searches for child pornography.

The source of child pornography was traced to an IP address used at the observatory and a source within the building observed a computer with “not good” images on it, the warrant states.

An investigation by the FBI revealed that a janitor is the main suspect in the search, however he has not been charged with a crime even though his name in on the warrant.

This might also explain why the post office was searched, assuming they were trying to trace further porn material there.

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Vulcan found?

Scientists have found a super-earth orbiting 40 Eridani-A, a star located sixteen light years away and proposed by Gene Roddenberry in 1991 as the home star for his race of logical Vulcans.

It turns out the letter authors’ prediction was right — a world really does orbit the primary star of the three-star 40 Eridani system. (Whether it’s home to a logic-based alien society, though, is anyone’s guess!)

The world is a super-Earth, the most common type of planet in the galaxy (though a type that’s missing from our solar system). At twice Earth’s radius and eight to nine times its mass, 40 Eridani b sits on the line that divides rocky super-Earths from gaseous ones. The planet orbits its star every 42 days, putting just inside the system’s habitable zone — in other words, where it’s nice and hot. At 16 light-years away, it’s the closest super-Earth known and therefore a good potential target for followup observations.

The discovery was made by a survey taking place using a relatively small telescope right here in the Tucson area, on top of Mount Lemmon. Most cool!

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Statement about closure of solar observatory

AURA, the university consortium that operates the closed Sunspot Solar Observatory in New Mexico, issued a statement today about that closure.

AURA has been cooperating with an on-going law enforcement investigation of criminal activity that occurred at Sacramento Peak. During this time, we became concerned that a suspect in the investigation potentially posed a threat to the safety of local staff and residents. For this reason, AURA temporarily vacated the facility and ceased science activities at this location.

The decision to vacate was based on the logistical challenges associated with protecting personnel at such a remote location, and the need for expeditious response to the potential threat. AURA determined that moving the small number of on-site staff and residents off the mountain was the most prudent and effective action to ensure their safety.

In light of recent developments in the investigation, we have determined there is no risk to staff, and Sunspot Solar Observatory is transitioning back to regular operations as of September 17th. Given the significant amount of publicity the temporary closure has generated, and the consequent expectation of an unusual number of visitors to the site, we are temporarily engaging a security service while the facility returns to a normal working environment.

We recognize that the lack of communications while the facility was vacated was concerning and frustrating for some. However, our desire to provide additional information had to be balanced against the risk that, if spread at the time, the news would alert the suspect and impede the law enforcement investigation. That was a risk we could not take.

This news release, while still very vague about the criminal investigation, implies that there was a dangerous criminal suspect on the mountain that federal officials were pursuing, and they evacuated to protect their employees.

This explanation still leaves serious questions. Why for example were local police kept in the dark about this investigation? It makes no sense not to include them, unless they might be a target of the investigation, something that in this case does not appear to be true.

Also, if there was a criminal on the mountain, secrecy is not really an effective way to catch him. It might make sense, but they have not provided us any information that would explain this.

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Astronomers use radio emissions from distant galaxy to observe asteroid

The wonders of science: Astronomers have successfully used the faint radio emissions from very distant galaxy to roughly determine the shape and size of a nearby asteroid.

In an unusual observation, astronomers used the National Science Foundation’s Very Long Baseline Array (VLBA) to study the effects on radio waves coming from a distant radio galaxy when an asteroid in our Solar System passed in front of the galaxy. The observation allowed them to measure the size of the asteroid, gain new information about its shape, and greatly improve the accuracy with which its orbital path can be calculated.

When the asteroid passed in front of the galaxy, radio waves coming from the galaxy were slightly bent around the asteroid’s edge, in a process called diffraction. As these waves interacted with each other, they produced a circular pattern of stronger and weaker waves, similar to the patterns of bright and dark circles produced in terrestrial laboratory experiments with light waves. “By analyzing the patterns of the diffracted radio waves during this event, we were able to learn much about the asteroid, including its size and precise position, and to get some valuable clues about its shape,” said Jorma Harju, of the University of Helsinki in Finland.

The amount of information is not great, and there is an enormous amount of uncertainty in the data. Nonetheless, this is an amazing and fascinating observation.

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Is mercury release cause of New Mexico solar observatory shutdown?

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

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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Astronomers retract prediction of star merger

The uncertainty of science: A review of the data has caused astronomers to retract a prediction that the two stars in a binary system were going to merge in 2022.

It appears that the mistaken prediction occurred because of a typo in the dataset they were using. The new analysis pinpointed this, which once corrected showed that no star merger is going to take place.

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TESS releases its first batch of exoplanet candidates

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

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

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

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

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

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

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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