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for the time being the Arecibo radio telescope can continue operations:


Press Statement 17-008
Arecibo: Statement on NSF Record of Decision

Decision formalizes NSF’s preferred path for maintaining science operations

November 16, 2017

On Nov. 15, 2017, the National Science Foundation (NSF) signed its Record of Decision for the Arecibo Observatory in Puerto Rico. This important step concludes the agency's decision-making process with respect to the general path forward for facility operations in a budget-constrained environment and provides the basis for a future decision regarding a new collaborator.

NSF issued its Record of Decision following authorization from the National Science Board on Nov. 9, 2017. That followed an extensive environmental impact analysis and broad input from the public and the scientific community, including the National Academies 6th Decadal Survey released in 2010, the NSF Division of Astronomical Sciences Portfolio Review Committee Report released in 2012 and the NSF Geospace Sciences Portfolio Review Committee Report released in 2016.

The decision formalizes the selection of NSF's preferred alternative: to collaborate with interested parties to maintain science-focused operations at the observatory with reduced agency funding. This plan will allow important research to continue while accommodating the agency's budgetary constraints and its core mission to support cutting-edge science and education.

NSF remains deeply concerned about the impacts from recent hurricanes on Arecibo Observatory staff, the facility and all citizens of Puerto Rico. The Record of Decision arrives at a challenging time, but is necessary for the agency to secure a future for the observatory. It will allow negotiations to begin with potential collaborators who may take over management and operations as NSF funding for the observatory is reduced.

-NSF-

 

 

 

https://www.nsf.gov/news/news_summ.jsp?cntn_id=243729

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Meanwhile China has opened the biggest radio bowl for business:

 

FAST Radio Telescope Open for Business
By: David Dickinson | September 27, 2016

China recently unveiled its FAST radio telescope, the world's largest single-dish radio telescope.

The Chinese Academy of Sciences announced this week that its new 500-meter Aperture Spherical Telescope (FAST) is now ready to scan the skies. With a dish 500 meters across, this behemoth is now the largest filled-in, single-dish radio telescope in the world. With an area equal to 30 soccer fields, a Nimitz-class aircraft carrier could easily float in the 500 meter FAST radio telescope's dish from bow to stern, with room to spare.

The completed Five-hundred-meter Aperture Spherical Telescope (FAST) as seen from the air.
Chinese Academy of Sciences

Only the 576-meter diameter of Russia's RATAN-600 system is physically larger than FAST, though its collecting surface is a large ring rather than a dish. It's not all about size though — RATAN-600 actually only has an effective collecting area of 12,000 m2. FAST radio telescope's effective collecting area is 70,000 m2. The 305-m-wide Arecibo Observatory in Puerto Rico, which formerly held the title of largest single dish radio telescope in the world, has an effective collecting area of about 31,000 m2.

Taking the FAST Track in Radio Astronomy

The enormous FAST radio telescope is in a sparsely populated region of southern China.
China Travel Service Group USA

FAST radio telescope is located in southwestern China in the sparsely populated Guizhou Province. Like Arecibo, the radio telescope was built inside a natural depression in the limestone-dominated terrain, and it uses mountainous karst features surrounding the observatory to block out radio interference.

In order to create a zone free of radio interference, China also relocated 9,110 people from villages in the surrounding area while building the FAST radio telescope.

First proposed in 1994, the project was green-lighted by the Chinese government in 2007, and groundbreaking followed the next year. Formal construction began in 2011. The last of the instrument's 4,450 reflecting panels was finally put into position earlier this year on July 3rd.

 

 

FAST will probe the universe at radio wavelengths, hunting for faint pulsars, mapping neutral hydrogen in distant galaxies, and searching for signs of extraterrestrial communications and intelligence.

“Once completed, FAST will lead the world for at least 10 to 20 years,” says director general and telescope designer Yan Jun (National Astronomical Observatories of China) in a recent press release.

FAST's expected resolution is 2.9 arcminutes, which is pretty good for single-dish radio astronomy. Although its surface is spherical overall, FAST uses actuators to push and pull on the corners of a 300-m-wide subset of the individual panels to attain a near-paraboloidal shape to achieve this focus.

The radio telescope now enters an extensive commissioning phase. FAST made its first observation of a pulsar 1,351 light-years away this past month.

FAST will also use the Next Generation Archive System (NGAS) developed by the International Center for Radio Astronomy (ICRAR) in Perth, Australia, and the European Southern Observatory to store and maintain the large amount of data it's expected to collect. NGAS expects to handle about 3 petabytes (3 × 1015 bytes) of data from FAST every year, enough to fill 120,000 single-layer, 25-gigabyte Blu-ray disks.

“This system is already being used by a whole suite of observatories around the world,” says Andreas Wicenec (University of Western Australia). “During the last few years the software has been significantly upgraded to support very large data streams like the ones coming out of SKA precursors.”

FAST at night.
Chinese Academy of Sciences

As with Arecibo, FAST's receivers, suspended high above the dish, are only partially steerable. Located at latitude 26°N, the radio telescope points straight overhead, allowing Earth's rotation to "point" the dish as the sky sweeps past. FAST's significantly deeper dish lends it a wider field of view than Arecibo's, though. It can cover a swath of sky within 40° of its zenith — Arecibo is limited to 20° from its zenith.

However, FAST uses a smaller receiver platform than Arecibo and does not house the large radar transmitters needed to ping large near Earth asteroids as part of planetary defense.

Big Radio Dishes: Past, Present & Future

The historic Lovell radio telescope at Jodrell Bank.
David Dickinson

FAST carries on the tradition of large radio telescope construction that started shortly after the Second World War. The 76.2-m Lovell Telescope at Jodrell Bank outside of Manchester, England, was completed in 1957. It was surpassed first by Green Bank in West Virginia, and later by the 100-m Effelsberg radio telescope in Germany. Since 1963, Arecibo has held the title of largest single-filled dish radio telescope until this year.

Perhaps, like the 40-inch Yerkes refractor, FAST's record-setting dimensions will never be exceeded. Future radio observatories such as the Square Kilometer Array will be "dish farms," like the Very Large Array in New Mexico, using the interference between the radio signal collected by many dishes to assemble high-resolution images.

FAST is set to usher in a new generation of radio astronomy, with more exciting science to come. Learn more about it at the facility's website.

 

 

 

Five-hundred-meter Aperture Spherical radio Telescope

 

FAST starts operation

The Five-hundred-meter Aperture Spherical radio Telescope (FAST) is a Chinese mega-science project aiming to build the largest single dish radio telescope in the world, with innovative concepts. It is funded by the National Development and Reform Commission (NDRC) and managed by the National Astronomical Observatories of Chinese Academy of Sciences (NAOC), with the government of Guizhou province as a cooperation partner. The project is expected to be completed by 25 September 2016.


 

http://fast.bao.ac.cn/en/

 

 

 

They missed the chance to name it Wide Open Kepler Telescope.

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Meanwhile China has opened the biggest radio bowl for business:

 

 

FAST Radio Telescope Open for Business
By: David Dickinson | September 27, 2016

China recently unveiled its FAST radio telescope, the world's largest single-dish radio telescope.

The Chinese Academy of Sciences announced this week that its new 500-meter Aperture Spherical Telescope (FAST) is now ready to scan the skies. With a dish 500 meters across, this behemoth is now the largest filled-in, single-dish radio telescope in the world. With an area equal to 30 soccer fields, a Nimitz-class aircraft carrier could easily float in the 500 meter FAST radio telescope's dish from bow to stern, with room to spare.

The completed Five-hundred-meter Aperture Spherical Telescope (FAST) as seen from the air.

Chinese Academy of Sciences

Only the 576-meter diameter of Russia's RATAN-600 system is physically larger than FAST, though its collecting surface is a large ring rather than a dish. It's not all about size though — RATAN-600 actually only has an effective collecting area of 12,000 m2. FAST radio telescope's effective collecting area is 70,000 m2. The 305-m-wide Arecibo Observatory in Puerto Rico, which formerly held the title of largest single dish radio telescope in the world, has an effective collecting area of about 31,000 m2.

Taking the FAST Track in Radio Astronomy

The enormous FAST radio telescope is in a sparsely populated region of southern China.

China Travel Service Group USA

FAST radio telescope is located in southwestern China in the sparsely populated Guizhou Province. Like Arecibo, the radio telescope was built inside a natural depression in the limestone-dominated terrain, and it uses mountainous karst features surrounding the observatory to block out radio interference.

In order to create a zone free of radio interference, China also relocated 9,110 people from villages in the surrounding area while building the FAST radio telescope.

First proposed in 1994, the project was green-lighted by the Chinese government in 2007, and groundbreaking followed the next year. Formal construction began in 2011. The last of the instrument's 4,450 reflecting panels was finally put into position earlier this year on July 3rd.

 

 

FAST will probe the universe at radio wavelengths, hunting for faint pulsars, mapping neutral hydrogen in distant galaxies, and searching for signs of extraterrestrial communications and intelligence.

“Once completed, FAST will lead the world for at least 10 to 20 years,” says director general and telescope designer Yan Jun (National Astronomical Observatories of China) in a recent press release.

FAST's expected resolution is 2.9 arcminutes, which is pretty good for single-dish radio astronomy. Although its surface is spherical overall, FAST uses actuators to push and pull on the corners of a 300-m-wide subset of the individual panels to attain a near-paraboloidal shape to achieve this focus.

The radio telescope now enters an extensive commissioning phase. FAST made its first observation of a pulsar 1,351 light-years away this past month.

FAST will also use the Next Generation Archive System (NGAS) developed by the International Center for Radio Astronomy (ICRAR) in Perth, Australia, and the European Southern Observatory to store and maintain the large amount of data it's expected to collect. NGAS expects to handle about 3 petabytes (3 × 1015 bytes) of data from FAST every year, enough to fill 120,000 single-layer, 25-gigabyte Blu-ray disks.

“This system is already being used by a whole suite of observatories around the world,” says Andreas Wicenec (University of Western Australia). “During the last few years the software has been significantly upgraded to support very large data streams like the ones coming out of SKA precursors.”

FAST at night.

Chinese Academy of Sciences

As with Arecibo, FAST's receivers, suspended high above the dish, are only partially steerable. Located at latitude 26°N, the radio telescope points straight overhead, allowing Earth's rotation to "point" the dish as the sky sweeps past. FAST's significantly deeper dish lends it a wider field of view than Arecibo's, though. It can cover a swath of sky within 40° of its zenith — Arecibo is limited to 20° from its zenith.

However, FAST uses a smaller receiver platform than Arecibo and does not house the large radar transmitters needed to ping large near Earth asteroids as part of planetary defense.

Big Radio Dishes: Past, Present & Future

The historic Lovell radio telescope at Jodrell Bank.

David Dickinson

FAST carries on the tradition of large radio telescope construction that started shortly after the Second World War. The 76.2-m Lovell Telescope at Jodrell Bank outside of Manchester, England, was completed in 1957. It was surpassed first by Green Bank in West Virginia, and later by the 100-m Effelsberg radio telescope in Germany. Since 1963, Arecibo has held the title of largest single-filled dish radio telescope until this year.

Perhaps, like the 40-inch Yerkes refractor, FAST's record-setting dimensions will never be exceeded. Future radio observatories such as the Square Kilometer Array will be "dish farms," like the Very Large Array in New Mexico, using the interference between the radio signal collected by many dishes to assemble high-resolution images.

FAST is set to usher in a new generation of radio astronomy, with more exciting science to come. Learn more about it at the facility's website.

 

 

 

Five-hundred-meter Aperture Spherical radio Telescope

 

FAST starts operation

 

The Five-hundred-meter Aperture Spherical radio Telescope (FAST) is a Chinese mega-science project aiming to build the largest single dish radio telescope in the world, with innovative concepts. It is funded by the National Development and Reform Commission (NDRC) and managed by the National Astronomical Observatories of Chinese Academy of Sciences (NAOC), with the government of Guizhou province as a cooperation partner. The project is expected to be completed by 25 September 2016.

 

http://fast.bao.ac.cn/en/

 

 

 

They missed the chance to name it Wide Open Kepler Telescope.

 

They missed an opportunity to open it at the weekends as the worlds largest skateboarding faciilty.

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Unlikely. Bacteria is known to change shape in microgravity, and there is bacteria known to live high in the atmosphere. Most likely this is "ordinary" terrestrial bacteria which has changed to an unfamiliar shape. It has been sampled, AIUI, and is getting a genetic profile done - which should show the origin definitively.

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  • 5 months later...

even if it is not a foreign visitor from outside our solar system, asteroids are not supposed to run backwards

 

 

Space
Astronomers Spot Potential "Interstellar" Asteroid Orbiting Backward around the Sun

The three-kilometer-wide object is near Jupiter; future spacecraft could visit if its status is confirmed

By Lee Billings on May 21, 2018



From time immemorial, people gazing up at the night sky have dreamed of reaching out to touch the stars. But today we know that even the closest ones are so far away that light itself, the fastest thing known, takes several years to make the trip. The dream of such a visit seems as remote as the stars themselves—unless, perhaps, the stars somehow send emissaries to us.

Remarkably, that may be happening. Last year astronomers spotted a curious body they called ‘Oumuamua, streaking through the solar system too fast to be caught in the sun’s gravitational clutches; its trajectory confirmed it was an interstellar voyager, tossed out from its unknown system long ago to drift alone through the galaxy. ‘Oumuamua was the first of its kind to be observed, and now it may have another newfound counterpart much closer to home.

Researchers Fathi Namouni of Côte d'Azur Observatory in France and Helena Morais of São Paulo State University in Brazil say they have identified an interstellar asteroid that, rather than passing through, somehow settled down in our solar system. If confirmed, the discovery would open the possibility for robotic missions to visit and investigate a piece of another planetary system without ever leaving our stellar home. The findings were published Monday in the Monthly Notices of the Royal Astronomical Society.


“This shows the solar system is home to objects which were born around other stars,” Morais contends. “Thus, matter in other star systems could influence the evolution of our own solar system.” That, in turn, would complicate the scenarios scientists have assembled to explain some of our solar system’s most fundamental mysteries, such as the detailed timing and mechanics of planet formation, the delivery of water and organic molecules to Earth, and even the genesis of life. Rather than originating here, for instance, could life have hitchhiked in after forming elsewhere in the galaxy? Each time astronomers find a space rock that could be an interstellar immigrant, the need grows to take such far-out ideas seriously.
Backwards in Orbit, Backwards in Time

Discovered in late 2014 via the Pan-STARRS telescope in Hawaii, the object was provisionally dubbed 2015 BZ509. Scarcely anything is known about it at all, save for its size (about three kilometers wide) and orbit, which is almost identical to Jupiter’s. Almost, that is, save for one important detail—BZ509’s orbit is backwards, or retrograde, meaning it moves in the opposite direction of the prograde orbits of almost everything else circling the sun.

This backward motion goes against the fundamental counterclockwise spin our solar system inherited from more than 4.5 billion years ago, when our star and its planets first coalesced from a whirling disk of gas and dust. BZ509’s retrograde status is doubly strange near Jupiter because the giant planet’s gravitational influence would tend to make such an orbit short-lived, tossing the object out of the solar system or down toward the sun within millennia. Such interactions with giant planets are thought to be the main way small objects become interstellar in the first place. Perhaps, scientists initially speculated, BZ509’s odd orbit was due to its origins in the Oort cloud—an enormous reservoir of comets ejected by Jupiter and the other giant planets to the outer limits of the solar system, where they can be disturbed by passing stars. If this were the case with BZ509, however, we would be seeing it at an exceedingly special and rare point in its history: a brief moment of illusory orbital stability that will soon decay into chaos.

Yet no comet-like emissions have been detected from BZ509, and it is in resonance with Jupiter, synchronized to periodically swoop within about 175 million kilometers of the giant planet’s cloud tops—just close and often enough for Jupiter to regularly provide gentle tugs that is keeping its orbit stable for at least a million years. So how did BZ509 get there? And how long will it stay?

To find out, Namouni and Morais built a virtual time machine. They used a supercomputer to simulate the possible motions of a million digital clones of BZ509, each with slightly different orbital parameters reflecting astronomers’ limited knowledge of the real object’s orbit. Running their simulation backwards across billions of years of virtual time, they watched almost all the clones succumb to orbital instability. But at 4.5 billion years ago—rewinding the clock to when the solar system was less than 100 million years old—they saw 46 clones remaining, twirling away in stable orbits.


If BZ509 has indeed been in its retrograde orbit that long, it would predate the generally accepted timeline for the Oort cloud’s formation by more than three billion years, making the cloud an implausible source. Instead, Namouni and Morais reason, our sun’s gravity must have captured the object after it was somehow ejected from the grasp of a nearby neighboring star. Such a star would likely have been a sibling of our sun born alongside us in a “stellar nursery”—a nebula filled with star-forming gas and dust. Galactic motions long ago scattered this progeny far and wide, but it seems remnants may linger on our doorstep today.

“We did not expect that the asteroid would remain bound to Jupiter and that it would hang on in there for 4.5 billion years, but it did!” Namouni says. “Since the asteroid's orbit was right there as it is now—in retrograde and in the same resonance with Jupiter—it can't have been born in the solar system.”
An Interstellar Origin—Maybe

Namouni and Morais’s argument hinges on the notion that, on average, the odds are against us being lucky enough to witness any asteroid at some extremely special moment in its history. Namouni expresses this as a simple rule: “If we have two possible orbits for the asteroid—one stable over the age of the solar system, and one that is unstable after say 10 million years—then it is the stable one that represents the real physical orbit.”

But critics say this “nothing special” reasoning cuts both ways. Namouni and Morais have not yet modeled the probability of an interstellar asteroid being captured into a stable retrograde orbit with Jupiter, and for that matter have not provided any detailed, step-by-step scenarios for how exactly this could occur. “The probability of a capture like this is certainly quite low. But how low is it?” asks Scott Tremaine, an astrophysicist at the Institute for Advanced Study in Princeton who did not take part in the work. “For a realistic flux of interstellar material, does capture happen often enough to make the discovery of such an object plausible?” In terms of probability, an interstellar origin for BZ509 could be exceedingly special in comparison to other rare but likelier alternatives, Tremaine says. He speculates BZ509 could have emerged through “some combination of a close encounter with Jupiter and a collision” with another object.

Not all the possible scenarios are so prosaic. Konstantin Batygin, an astrophysicist at Caltech, also not involved with the work, suggests a wild possibility: Planet Nine, a hypothetical 10-Earth-mass undiscovered world far beyond Pluto that Batygin proposed in 2016 with fellow Caltech astronomer Mike Brown, would inevitably “pollute” the solar system with retrograde objects much like BZ509 as it drifts through the outer solar system. “So do you need to draw [bZ509] from the interstellar medium? No—Planet Nine would give it to you for free,” Batygin says. “The interstellar interpretation is one possibility; Planet-Nine-induced dynamics provide an alternative.”


Additionally, Tremaine says, the idea that BZ509 simply came from the Oort cloud cannot be easily dismissed, in part because there is no good reason to believe the object was actually captured 4.5 billion years ago or earlier (before the Oort cloud’s estimated formation circa one billion years ago). “If these objects are captured at a steady rate and all survive, yes, you would expect a typical one to have arrived a few billion years ago,” he says. “But if most of the captured objects are lost on much-shorter timescales as expected, the typical ones we’d see would be younger.”

Even if BZ509 came from the Oort cloud, Namouni counters, it could still have originated from beyond the solar system—because the Oort cloud itself could in theory be largely composed of comets captured from interstellar space. An interstellar origin for the Oort cloud could only have occurred prior to 4.5 billion years ago, when our newborn sun was still embedded in its stellar nursery—a decidedly non-standard scenario, but one consistent with Namouni and Morais’s dating of BZ509 to the dawn of the solar system.
The Brick and the Truck

Certainty about BZ509’s origins can only come from follow-up studies. This would specifically entail searches for additional interstellar interlopers, which Namouni and Morais predict should pile up in orbits roughly perpendicular to the plane in which the known planets orbit the sun. Then, Morais says, “it would be very interesting to analyze the composition of this object and other immigrant candidates,” to seek out chemical signatures of their births around alien suns and subsequent journeys through the spaces between the stars. “The more we identify interstellar asteroids in the solar system,” Morais adds, “the more we understand their influence on its evolution.”

For BZ509 in particular, she says, “a robotic interplanetary mission is highly desirable and feasible, because the asteroid is not far away from Earth.” And, in fact, such missions are already in embryonic phases of planning. After ‘Oumuamua stormed through the solar system in 2017, scientists began studying how such objects could be intercepted and studied.

The most realistic approach is also the cheapest and easiest, as laid out in a paper by Yale University astrophysicists Darryl Seligman and Greg Laughlin. Given sufficient early warning by ground-based telescopes, a probe could be launched into the path of any future ‘Oumuamua-like interstellar asteroid as it reaches its closest point to Earth. The asteroid would be moving too fast for the probe to match its velocity, but the probe could eject a hefty “impactor” to strike the object as it flies by—“like throwing a brick in front of a speeding truck,” Seligman says. The impact would eject a plume from the object’s interior that both the probe and Earth-bound observers could then study telescopically. (Incidentally, NASA already performed a mission much like this in 2005, when its Deep Impact spacecraft raised and studied a plume from the ordinary comet Tempel 1.)


Because of BZ509’s retrograde motion, Seligman says, the Deep-Impact-style approach would be ideal. Sending a spacecraft to gently land upon or orbit the object would be extremely difficult, as such a probe would have to burn huge amounts of fuel to cancel out its prograde velocity. But the relative velocities of a prograde “brick” in the path of a retrograde “truck” would be huge, enough to easily produce an enormous plume.

“What’s nice about BZ509 is that it’s not leaving our solar system, whereas with an ‘Oumuamua-like object you just get one shot,” Seligman says. “So you can really take your time and plan out the best point in its orbit to hit it.” Even so, he says, any BZ509 mission is unlikely to get off the ground anytime soon, given the uncertainties about the object’s true origins. “The case for BZ509 to be interstellar looks good and compelling, but people will still probably find other ways to explain its retrograde orbit—it’s not quite the same as having an object shooting through our solar system like ‘Oumuamua did.”

 

 

https://www.scientificamerican.com/article/astronomers-spot-potential-interstellar-asteroid-orbiting-backward-around-the-sun/

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  • 2 months later...

The game is on! On the German side, the imperial horse of Wilhelm I. kicks off the moon in Koblenz ...

 

 

... passes to Dresden, where Benedict of Nursia effortlessly sends it on towards Warsaw ...

 

 

... but in a heroic action, Nike saves! The game is still nil-nil.

 

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Got to watch it, though slightly underwhelming in Hannover. Needless to say, even when I found a spot to observe things close to the horizon, haze was thick so it was barely recognizable at first. But, patience was rewarded, shortly before the end Mars became finally visible as well, so as I had seen everything there was to see, I could ride back home.

The week before, it was actually a very pleasant evening at a faux beach in Dutch Harderwijk with Venus, Saturn, Jupiter, and the moon on a nice string after sunset, and the ISS passing over as an unexpected fringe bonus. :)

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Unfortunately it was cloudy last night here in Sopron, and mostly in Hungary. Some news say it was visible here about half hour later (and a quarter before the total phase ended) that I have returned home.

 

A photo taken by Ferenc Bogádi over the Mediterranean Sea, at 10.800 meters height:

 

20634532_296b801d8c46d582ac63a47df1cf379

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  • 1 month later...

"Fascinating" a certain half-breed would say.

 

Super-Earth Discovered in (Fictional) Vulcan System
By: Monica Young |

September 17, 2018



Thirty years ago, three astronomers and Gene Roddenberry, of Star Trek fame, made the case to Sky & Telescope readers that the orange-hued star 40 Eridani A ought to host Vulcan, Spock's home. Now, a robotic survey has discovered a planet around that very star.


Almost three decades ago, Gene Roddenberry (producer of the Star Trek universe) wrote a letter to Sky & Telescope, along with Harvard-Smithsonian Center for Astrophysics astronomers Sallie Baliunas, Robert Donahue, and George Nassiopoulos. In their Letter to the Editor, they argued that 40 Eridani A — an orange-ish star 16 light-years away — would make the ideal home for Vulcan, the home planet of Science Officer Mr. Spock.

Now, a new discovery puts a little more science into that science fiction assertion.


A Long-ago Letter

In the July 1991 issue, the three astronomers and one movie-maker made the case for what star should be considered Vulcan's home:



The star around which Vulcan orbits was never identified in the original series or in any of the feature films based on it and so has never been officially established. But two candidates have been suggested in related literature.




Two Star Trek books named the star 40 Eridani A as Vulcan's sun, while another publication named Epsilon Eridani instead. However, Roddenberry and the astronomers made an argument for 40 Eridani A:


We prefer the identification of 40 Eridani as Vulcan's Sun because of what we have learned about both stars at Mount Wilson. . . . The HK [Project] observations suggest that 40 Eridani is 4 billion years old, about the same age as the Sun. In contrast Epsilon Eridani is barely 1 billion years old.

Based on the history of life on Earth, life on any planet around Epsilon Eridani would not have had time to evolve beyond the level of bacteria. On the other hand, an intelligent civilization could have evolved over the aeons on a planet circling 40 Eridani. So the latter is the more likely Vulcan sun. . . . Presumably Vulcan orbits the primary star, an orange main-sequence dwarf of spectral type K1. . . . Two companion stars — a 9th magnitude white dwarf and an 11th magnitude red dwarf — orbit each other about 400 astronomical units from the primary. They would gleam brilliantly in the Vulcan sky.



Dharma Discovery
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 comes courtesy of the Dharma Planet Survey, designed to detect and characterize low-mass planets around bright, nearby stars. Started in 2016 and continuing until 2020, this survey uses a robotic 50-inch telescope on Mount Lemmon to look for planet-induced wobbles in 150 bright stars within 160 light-years of Earth. The spectrograph attached to the scope can measure radial velocities down to 1 meter per second, which enables it to find low-mass planets around these nearby stars.
The discovery will appear in the Monthly Notices of the Royal Astronomical Society. Read the preprint here.

 


https://www.skyandtelescope.com/astronomy-news/super-earth-vulcan/

Edited by Panzermann
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"Fascinating" a certain half-breed would say.

 

The world is a super-Earth, the most common type of planet in the galaxy

 

 

Ugh.

We can't detect much smaller worlds right now. That hardly makes them the most common type of planet of the galaxy, but of the currently known sample. But we know that the sample has a systematic bias in what planets we can detect with current technology.

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"Fascinating" a certain half-breed would say.

 

The world is a super-Earth, the most common type of planet in the galaxy

 

Ugh.

We can't detect much smaller worlds right now. That hardly makes them the most common type of planet of the galaxy, but of the currently known sample. But we know that the sample has a systematic bias in what planets we can detect with current technology.

 

Yes, that way of putting it is misleading. Of course what we can find is limited by what our methods can do. But the casual reader would take away that so called super-earths are most common. A few years ago it was gas giants, because we could not find anything smaller. And that was the state of the universe. If our planet is really rare or not, we cannot actually say.

 

 


 

prediction of merging stars to be observed turns out to be wrong because of a writing error

 

Team of researchers challenge bold astronomical prediction

September 07, 2018 | Matt Kucinski

 

Calvin College professor of astronomy Larry Molnar made a bold announcement in 2017he and his team had identified a binary star in the constellation Cygnus, the Swan, that was a strong candidate to merge and explode in the near future. Known by its Kepler mission number, KIC 9832227, the pair of stars is about 1800 light years from Earth and has an orbit so close that it takes just 11 hours to go around once. That first-of-its-kind prediction caught the attention of an international audience, creating excitement within the scientific community and among the general public.

 

Digging deeper

The interest led Molnars peers to dig deeper into the discovery, in essence doing what Molnar says is good sciencescrupulously testing his prediction.

Now, 18 months later, a team of researchers led by Quentin Socia, a graduate student at San Diego State University, has published a paper in the Astrophysical Journal Letters reevaluating Molnars predicted merger, concluding it will not happen. And Molnar agrees with that assessment.

Good science makes testable predictions, said Molnar. There have been a few other papers that have tried to poke at our project, and weve been able to poke backcriticisms that just dont fly. But this one does fly, and I think they have a good point. This illustrates how science can be self-correcting.

 

(...)

 

The discrepant NSVS value was traced to a typographical error in the paper published to describe the 1999 data. The paper misrepresented the time of the eclipse by exactly 12 hours. This, in turn, put Molnars calculation off by one orbit (11 hours) plus one hour. Finally, the revised status of what occurred from 1999 to 2003 alters predictions for the future. So, the agreement between the past year of measurements and Molnars published prediction must now be seen as a coincidence rather than a confirmation.

(...)

https://calvin.edu/news/archive/team-of-researchers-challenge-bold-astronomical-prediction Edited by Panzermann
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  • 3 weeks later...

And BTW, happy Halloween.

 

 

Sorta.

 

Settle down, guys. A skull-shaped asteroid is not headed for Earth this Halloween

 

By AnneClaire Stapleton and Artemis Moshtaghian, CNN

 

Updated 2233 GMT (0633 HKT) September 29, 2018

(CNN) - Despite what your social media feeds are telling you, an asteroid shaped like a skull is not going to zip by Earth this Halloween.

Asteroid 2015 TB145 looked like a skull when it passed by our planet three years ago on Halloween. But now the object may be a bit less "humerous," because its shape may since have changed.
In 2015, the asteroid missed Earth by just 300,000 miles and was visible to those with good telescopes. This year, the closest it will come is 25 million miles -- which is way too far to tell what it looks like.
"This time it's not coming close enough (to Earth) to be any larger than a dot of light," said Paul Chodas, manager of NASA's Jet Propulsion Laboratory Center for Near Earth Object Studies.
The asteroid was previously estimated to be 2,000 feet in diameter. However, asteroids change shape over time, as they smash into other celestial objects and break apart.
What's more, the giant rock won't be at its closest until November 11, well after Halloween.
NASA says the asteroid is most likely a "dead" comet that once spewed debris across the solar system. In space talk, that means it has "shed its volatiles" that would produce the visible tail seen on some comets.
The asteroid was discovered October 10, 2015, by the University of Hawaii's Pan-STARRS-1 (Panoramic Survey Telescope and Rapid Response System) telescope in Haleakala, on the island of Maui.

 

https://edition.cnn.com/2018/09/29/world/skull-asteroid-halloween-trnd/index.html

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