Tag Archives: astronomy

Astronomers identify likely origin star for interstellar Comet Borisov

Astronomers have backtracked the path of interstellar Comet Borisov to identify its likely origin.

When you rewind Comet Borisov’s path through space, you’ll find that 1 million years ago, the object passed just 5.7 light-years from the center of Kruger 60, moving just 2.13 miles per second (3.43 kilometers per second), the researchers wrote.

That’s fast in human terms —— about the top speed of an X-43A Scramjet, one of the fastest aircraft ever built. But an X-43A Scramjet can’t overcome the sun’s gravity to escape our solar system. And the researchers found that if the comet were really moving that slowly at a distance of no more than 6 light-years from Kruger 60, it probably wasn’t just passing by. That’s probably the star system it came from, they said. At some point in the distant past, Comet Borisov likely orbited those stars the way comets in our system orbit ours.

The remains some uncertainty about these calculations because astronomers are still gathering data on the comet’s path.

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World’s largest camera lens arrives safely for assembly into LSST

Link here. The lens will be part of the camera used in the Large Synoptic Survey Telescope (LSST), planned for first light in Chile in 2021, and the video at the link showed the moment they removed the shipping container to inspect the lens to make sure it wasn’t damaged during transport.

The lens will next be installed inside the 3.2 gigapixel camera that will be used by LSST, which will do the following:

The LSST will live on a mountain in Chile, where it will use a 3.2-gigapixel camera and some massive optics to capture a 15-second exposure of the night sky every 20 seconds. At this rate, the LSST will be able to image the entire visible southern sky every few nights.

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I have embedded the video below the fold. This five foot diameter lens is quite astonishing, though the technology that produced it is merely a variation of the same engineering that now routinely produces telescope mirrors 26 feet across.

Hat tip Mike Nelson.
» Read more

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Astronomers find 20 more moons orbiting Saturn

Astronomers have discovered an additional twenty moons orbiting Saturn, bringing the total known to 82, three more than the 79 moons known to circle Jupiter.

Each of the newly discovered moons is about five kilometers, or three miles, in diameter. Seventeen of them orbit the planet backwards, or in a retrograde direction, meaning their movement is opposite of the planet’s rotation around its axis. The other three moons orbit in the prograde—the same direction as Saturn rotates.

Two of the prograde moons are closer to the planet and take about two years to travel once around Saturn. The more-distant retrograde moons and one of the prograde moons each take more than three years to complete an orbit.

The astronomers have also created a contest allowing the public to help name these new moons.

I will make one prediction: They are going to find many more.

In fact, Saturn’s rings and its numerous moons raise the question of what defines a moon. At present, a moon is defined as any object orbiting a planet, regardless of size. With Saturn’s rings however we have millions of objects orbiting that planet, many very tiny. It seems we have never put a size limit on the definition of a moon, and really need to.

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Astronomers photograph baby binary system

Baby binary stars dance in joint accretion disk
Click for full image.

Using the Atacama Large Millimetre/submillimetre Array (ALMA), astronomers have obtained the first high resolution image of a baby binary system, its two young stars dancing within a joint accretion disk.

Most stars in the universe come in the form of pairs – binaries – or even multiple star systems. Now, the formation of such a binary star system has been observed for the first time with high-resolution ALMA (Atacama Large Millimetre/submillimetre Array) images. An international team of astronomers led by the Max Planck Institute for Extraterrestrial Physics targeted the system [BHB2007] 11, the youngest member of a small cluster of young stellar objects in the Barnard 59 core in the Pipe nebula molecular cloud. While previous observations showed an accretion envelope surrounding a circum-binary disk, the new observations now also reveal its inner structure.

“We see two compact sources, that we interpret as circum-stellar disks around the two young stars,” explains Felipe Alves from MPE, who led the study. “The size of each of these disks is similar to the asteroid belt in our Solar System and their separation is 28 times the distance between the Sun and the Earth.” Both proto-stars are surrounded by a circum-binary disk with a total mass of about 80 Jupiter masses, which contains a complex network of dust structures distributed in spiral shapes. The shape of the filaments suggests streamers of in-falling material, which is confirmed by the observation of molecular emission lines.

Why most stars form as binary systems is as yet not understood. This data is a major first step towards figuring this out.

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Astronomers roughly map out Andromeda’s history

The uncertainty of science: Astronomers have now roughly mapped out the history of the Andromeda galaxy, identifying two major events whereby it had absorbed nearby dwarf galaxies.

“It’s been known for 10 to 15 years that Andromeda has a vigorous history of accumulating and destroying its neighbours,” Mackey says. In fact, he says, “It seems to have a much more intense history of that than the Milky Way.”

…[New data] “tells us there were two main events that formed the halo of Andromeda,” Mackey says. “One occurred very long ago. The other must have happened relatively recently.”

Not that Andromeda couldn’t also have eaten innumerable smaller galaxies. ”We can’t trace them with galactic clusters, because they didn’t have any to begin with,” Mackey says.

Most of the news reports about this new research have been very overwrought (Andromeda is “violent” and is going to “eat us!”) and very unaware that the assimilation of nearby small galaxies by Andromeda is not really news. Astronomers have known for years that big galaxies like Andromeda and the Milky Way absorb the dwarf galaxies around them. All this story does is postulate a more detailed though very rough timeline.

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China to open FAST radio telescope to world

China has decided to allow astronomers worldwide to apply for time on its new FAST radio telescope, the largest such telescope in the world.

Since testing began in 2016, only Chinese scientists have been able to lead projects studying the telescope’s preliminary data. But now, observation time will be accessible to researchers from around the world, says Zhiqiang Shen, director of the Shanghai Astronomical Observatory and co-chair of the Chinese Academy of Sciences’ FAST supervisory committee.

Obviously U.S. astronomers are going to want to use this telescope. I wonder if there will be security issues. I suspect that if they only request time and then make observations, there will be no problems. However, if they need to do anything that will require the use of U.S. technology, in China, then they may find themselves violating the U.S. law that forbids any technology transfer to China.

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First data suggests Comet Borisov resembles solar comets

The first spectrum obtained from Comet Borisov suggests that it is quite similar to comets in our solar system.

The gas detected was cyanogen, made of a carbon atom and a nitrogen atom bonded together. It is a toxic gas if inhaled, but it is relatively common in comets.

The team concluded that the most remarkable thing about the comet is that it appears ordinary in terms of the gas and dust it is emitting. It looks like it was born 4.6 billion years ago with the other comets in our Solar system, yet has come from an – as yet – unidentified star system.

It is still very early, so drawing any firm conclusions at this point is risky.

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Planet X a small black hole?

In one of the wilder theories attempting to explain the orbits of the outer objects found beyond Neptune, two physicists have proposed that the reason Planet X has not been located is because it might be a small black hole.

Previous studies have suggested Planet Nine, which some astronomers refer to as “Planet X,” has a mass between five and 15 times that of Earth and lies between 45 billion and 150 billion kilometers from the sun. At such a distance, an object would receive very little light from the sun, making it hard to see with telescopes.

To detect objects of that mass, whether planets or black holes, astronomers can look for weird blobs of light formed when light “bends” around the object’s gravitational field on its journey through the galaxy (simulated image above). Those anomalies would come and go as objects move in front of a distant star and continue in their orbit.

But if the object is a planet-mass black hole, the physicists say, it would likely be surrounded by a halo of dark matter that could stretch up to 1 billion kilometers on every side. And interactions between dark matter particles in that halo—especially collisions between dark matter and dark antimatter—could release a flash of gamma rays that would betray the object’s presence, the researchers propose in a forthcoming paper posted on the preprint server arXiv.

Anything is possible, but some things are certainly less likely than others. If these scientists turn out to be right, however, they will have achieved one of the biggest coups in the history of science.

And yes, the undiscovered planet out there should be referred to as “Planet X”, not “Planet Nine.” Not only is Pluto a planet, so are a lot of other objects in the solar system that up to recently were not considered so.

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A big planet circling a small star

The uncertainty of science: In contradiction of every existing stellar and planetary formation model, astronomers have found a half-sized Jupiter exoplanet orbiting a tiny red dwarf star.

The red dwarf GJ 3512 is located 30 light-years from us. Although the star is only about a tenth of the mass of the Sun, it possesses a giant planet – an unexpected observation. “Around such stars there should only be planets the size of the Earth or somewhat more massive Super-Earths,” says Christoph Mordasini, professor at the University of Bern and member of the National Centre of Competence in Research (NCCR) PlanetS: “GJ 3512b, however, is a giant planet with a mass about half as big as the one of Jupiter, and thus at least one order of magnitude more massive than the planets predicted by theoretical models for such small stars.”

It appears the universe does not care what this and other scientists think “should” happen. The universe will do what the universe wants to do.

This discovery only underlines how little we understand of the formation of stars and their solar system. Be prepared for many more like surprises in the coming decades and centuries.

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Astronomer: Look for monolith on co-orbiting asteriods

According to one astronomer in a paper published this week, the most likely place to find alien artifacts would be on the co-orbital asteroids, objects whose orbit is very similar to the Earth and thus always nearby but mostly unseen.

In this context, a co-orbital is an asteroid that goes around the Sun on the same, or similar, orbital path to Earth. Co-orbital objects approach Earth very closely every year at distance is much shorter than anything except the moon.

Consequently, co-orbitals could be a great place to watch Earth from. Not only would any alien probes on co-orbital objects be concealed, but they would also be anchored and able to access solar energy. They could possibly sustain themselves for many thousands of years.

According to this paper, if aliens have visited the solar system in the past they would place their long-term alien probes on such an asteroid, or even give it a comparable co-orbit. And if we look and don’t find anything, that would strongly imply that we are alone in the universe.

Fun stuff, but need I say that not finding alien artifacts at these locations proves nothing.

Hat tip Jeff Bliss.

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Scientists propose mission to interstellar comet Borisov

In a paper published on the Cornell arXIiv site for preprint science papers, scientists have posted a paper proposing sending an unmanned probe to the newly discovered interstellar Comet Borisov, arriving in 2045.

You can download the paper here. [pdf]

Their analysis found that we just missed the ideal and most efficient launch date using the Falcon Heavy. If it had launched in July 2018 a two-ton spacecraft could have reached Comet Borisov by next month.

The best alternative option is a launch in January 2030, flying past Jupiter, then the Sun, and arriving in 2045. Because of the mission’s close approach to the Sun to gain speed, the mission would require the type of shielding developed for the Parker Solar Probe. If the Space Launch System was used for launch, a six-ton spacecraft could be sent. With other available rockets the largest possible payload would be 3 kilograms (about 6 pounds), making the probe a cubesat. As they note,

Despite this very low mass, a CubeSat-scale spacecraft could be sent to the interstellar object. Existing interplanetary CubeSats (Mars Cube One) show that there is no principle obstacle against using such a small spacecraft to deep space.

In fact, having a decade and a half before launch guarantees that a cubesat will be able to do this job, because by 2030 the technology for using smallsats for this kind of planetary mission should be fully developed.

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The never-ending snowstorm circling Saturn

New data suggests that the water being spewed out of Enceladus’s tiger stripes is depositing so much snow and ice on Saturn’s three inner moons, Mimas, Enceladus and Tethys, that these moons, as well as Enceladus, are about twice as bright in radar than previously thought.

Dr Le Gall and a team of researchers from France and the US have analysed 60 radar observations of Saturn’s inner moons, drawing from the full database of observations taken by the Cassini mission between 2004 and 2017. They found that previous reporting on these observations had underestimated the radar brightness by a factor of two.

Unprotected by any atmospheres, Saturn’s inner moons are bombarded by grains of various origins which alter their surface composition and texture. Cassini radar observations can help assess these effects by giving insights into the purity of the satellites’ water ice.

The extreme radar brightness is most likely related to the geysers that pump water from Enceladus’s internal ocean into the region in which the three moons orbit. Ultra-clean water ice particles fall back onto Enceladus itself and precipitate as snow on the other moons’ surfaces.

Dr Le Gall, of LATMOS-UVSQ, Paris, explained: “The super-bright radar signals that we observe require a snow cover that is at least a few tens of centimetres thick. However, the composition alone cannot explain the extremely bright levels recorded. Radar waves can penetrate transparent ice down to few meters and therefore have more opportunities to bounce off buried structures. The sub-surfaces of Saturn’s inner moons must contain highly efficient retro-reflectors that preferentially backscatter radar waves towards their source.”

While the new results suggest that the surfaces of these moons are much brighter that expected, I find the circumstances they describe far more fascinating: a never-ending snow storm in the orbits around Saturn and landing continually on these moons.

My, isn’t the universe wonderful?

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Io volcano erupts like Ol’ Faithful

Having determined that Io’s largest volcano appears to erupt on a regularly schedule, scientists have predicted that a new eruption should occur sometime in the next week or so.

The volcano Loki is expected to erupt in mid-September, 2019, according to a poster by Planetary Science Institute Senior Scientist Julie Rathbun presented today.

“Loki is the largest and most powerful volcano on Io, so bright in the infrared that we can detect it using telescopes on the Earth,” Rathbun said. Based on more than 20 years of observations, Loki undergoes periodic brightenings when it erupts on a relatively regular schedule. In the 1990s, that schedule was approximately every 540 days. It currently appears to be approximately every 475 days. Rathbun discovered the 540-day periodicity, described in her 2002 paper “L. Loki, Io: A periodic volcano” that appeared in Geophysical Research Letters.

These same scientists successfully predicted Loki’s last eruption based on this data, but also warn that there is no guarantee the volcano will do what they say. As stock brokers are required to say, past performance is no guarantee of future results.

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New data cuts neutrino mass in half

The uncertainty of science: New data now suggests that the highest mass possible for the neutrino is about half the previous estimates.

At the 2019 Topics in Astroparticle and Underground Physics conference in Toyama, Japan, leaders from the KATRIN experiment reported Sept. 13 that the estimated range for the rest mass of the neutrino is no larger than about 1 electron volt, or eV. These inaugural results obtained earlier this year by the Karlsruhe Tritium Neutrino experiment — or KATRIN — cut the mass range for the neutrino by more than half by lowering the upper limit of the neutrino’s mass from 2 eV to about 1 eV. The lower limit for the neutrino mass, 0.02 eV, was set by previous experiments by other groups.

This lower limit does not tell us what the neutrino actually weighs, only reduces the uncertainty of the range of possible masses.

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New theory says evaporating exomoon explains Tabby’s Star

Astronomers have proposed a new theory for the random and inexplicable light variations that Tabby’s Star undergoes, a melting and evaporating exomoon.

The Columbia team suggests that Tabby’s Star abducted an exomoon from a now long-gone, nearby planet and pulled it into orbit around itself, where it has been getting torn apart by stronger stellar radiation than existed in its former orbit. Chunks of the exomoon’s dusty outer layers of ice, gas, and carbonaceous rock have been able to withstand the radiation blow-out pressure that ejects smaller-grain dust clouds, and the volatile, large-grain material has inherited the exomoon’s new orbit around Tabby’s Star, where it forms a disk that persistently blocks the star’s light. The opaqueness of the disk can change slowly, as smaller-grain clouds pass through and larger particles stuck in orbit move from the disk toward Tabby’s Star, eventually getting so hot that they melt and fall onto the star’s surface.

Ultimately, after millions of years, the exomoon orbiting Tabby’s Star will completely evaporate, the researchers suggest.

The article does not explain why the theory requires this exoplanet to have once been a moon to another exoplanet, now gone. It seems to me that this is adding unnecessary complexity to the solution, but I have not read the paper itself, so their might be reasons.

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Stony-iron asteroid caused flash on Jupiter in August

According to an analysis of the data obtained from the light flash that occurred when an object hit Jupiter on August 7, scientists have estimated its probably make-up, mass, and size.

They estimate from the energy released by the flash that the impactor could have been an object around 12-16 metres in diameter and with a mass of about 450 tons that disintegrated in the upper atmosphere at an altitude of about 80 kilometres above Jupiter’s clouds. Sankar and Palotai’s models of the light-curve for the flash suggest the impactor had a density typical of stony-iron meteors, indicating that it was a small asteroid rather than a comet.

Their conclusions are strengthened because they were able to compare this flash with five other similar but not as bright flashes, all detected since 2010.

These recent detections, all by amateurs, are because of the higher quality equipment now available to ordinary people, including the use of computers and remote operation. This technology is making it possible for amateurs to discover things that once only professionals could find.

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First high quality image of interstellar comet

Comet Borisov
Click for full image.

The Gemini Observatory on Mauna Kea has successfully taken the first high resolution image of comet C_2019 Q4, unofficially Comet Borisov (after its discoverer), the first interstellar comet ever discovered.

The image to right, cropped to post here, is that image. It clearly shows the growth of a coma and possible tail, indicating that as it is approaching the Sun it is releasing material from its surface.

Right now the comet is visually very close to the Sun, when looked at from the Earth, making observations difficult. As in the next few months it drops towards its closest approach of the Sun, and the Earth circles around in its own orbit, the viewing angle will improve.

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New Hubble image of Saturn

Saturn taken by Hubble in 2019
Click for full image.

Astronomers have used the Hubble Space Telescope to snap a new high resolution image of Saturn. That image, cropped and reduced to post here, can be seen on the right.

The image was part of a new Hubble program to obtain regular images of the outer planets, begun in 2018.

[The Saturn images] reveal a planet with a turbulent, dynamic atmosphere. This year’s Hubble offering, for example, shows that a large storm visible in the 2018 Hubble image in the north polar region has vanished. Smaller storms pop into view like popcorn kernels popping in a microwave oven before disappearing just as quickly. Even the planet’s banded structure reveals subtle changes in color.

But the latest image shows plenty that hasn’t changed. The mysterious six-sided pattern, called the “hexagon,” still exists on the north pole. Caused by a high-speed jet stream, the hexagon was first discovered in 1981 by NASA’s Voyager 1 spacecraft.

As beautiful as this Hubble photograph is, I cannot help but be saddened by it. It is now the best image of Saturn we will get until 2036 at the earliest, when a NASA mission to Titan finally arrives.

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Interstellar comet discovered?

An amateur astronomer has discovered what appears right now to be an interstellar comet making its approach into the solar system.

[I]mages show that the incoming object sports a faint but distinct coma and the barest hint of a tail — something ‘Oumuamua lacked — and thus appears to be a comet. Astronomers are no doubt eager to get spectra of the new find to determine what compounds might be escaping from its surface.

Based on current observations, C/2019 Q4’s eccentricity is about 3.2 — definitely hyperbolic. Objects on hyperbolic orbits are unbound to the Sun. They’re most likely to hail from beyond the solar system, flying in from great distances to pay our neighborhood a brief visit before heading off for parts unknown.

If this result holds up, astronomers have an unprecedented opportunity to study a potentially interstellar object in great detail over a long span of time. Based on the comet’s current magnitude (~18) and distance from the Sun (2.7 a.u.), it appears to be a fairly large object — perhaps 10 km or more across, depending on the reflectivity of its surface.

There remains a great deal of uncertainty about comet’s path, which will be better resolved with time and better data.

If it is a comet from beyond the solar system, it will be a spectacular goldmine for scientists, because its coma and tail will allow them to gather a great deal of information about its make-up, far more than they were able to gather about Oumuamua.

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Water found on exoplanet in habitable zone

The uncertainty of science: Astronomers now believe they have detected water in the atmosphere of an exoplanet that is also in habitable zone.

A new study by Professor Björn Benneke of the Institute for Research on Exoplanets at the Université de Montréal, his doctoral student Caroline Piaulet and several of their collaborators reports the detection of water vapour and perhaps even liquid water clouds in the atmosphere of the planet K2-18b.

…This exoplanet is about nine times more massive than our Earth and is found in the habitable zone of the star it orbits. This M-type star is smaller and cooler than our Sun, but due to K2-18b’s close proximity to its star, the planet receives almost the same total amount of energy from its star as our Earth receives from the Sun.

The size and mass of the this exoplanet means life as we know it probably does not exist there, either on its surface or in its atmosphere. Nonetheless, with water and the right amount of energy, anything is still possible.

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The end of the Thirty Meter Telescope?

The arriving dark age: It appears that the protests in Hawaii that are preventing the construction of the Thirty Meter Telescope might end up killing the telescope completely.

The problem is twofold. First, the Democratic-controlled government in Hawaii is willing to let the protesters run the show, essentially allowing a mob to defy the legal rulings of the courts:

The Native Hawaiian protesters blocking the construction of the Thirty Meter Telescope (TMT) on the summit of Mauna Kea appear to have settled in for the long haul. After 2 months of protests, their encampment on the Mauna Kea access road has shops, a cafeteria, and meeting spaces. “It’s like a small village,” says Sarah Bosman, an astronomer from University College London who visited in July. “There are signs up all over the island. It was a bit overwhelming really.”

Second, there is opposition to the alternate backup site in the Grand Canary Islands, both from local environmental groups and from within the consortium that is financing the telescope’s construction.

Astronomers say that the 2250-meter-high site, about half as high as Mauna Kea, is inferior for observations. Canada, one of six TMT partners—which also include Japan, China, India, the California Institute of Technology, and the University of California—is especially reluctant to make the move and could withdraw from the $1.4 billion project, which can ill afford to lose funding. Finally, an environmental group on La Palma called Ben Magec is determined to fight the TMT in court and has succeeded in delaying its building permit. It says the conservation area that the TMT wants to build on contains archaeological artifacts. “They’re willing to fight tooth and nail to stop TMT,” says Thayne Currie, an astronomer at the NASA Ames Research Center in Mountain View, California.

We now live in a culture that is opposed to new knowledge. It is also a culture that prefers mob rule, giving power to the loudest and possibly most violent protesters, while treating the law as a mere inconvenience to be abandoned at the slightest whim of those mobs.

If this doesn’t define a dark age, I’m not sure what does.

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China’s FAST radio telescope discovers 93 new pulsars

The research team running China’s FAST radio telescope, the largest single dish such telescope in the world, have announced that they have discovered 93 new pulsars since October 2017.

China might still be having trouble finding a big name astronomer to run the telescope, but in the meantime it looks like their own people are taking advantage of the situation to use the telescope establish their own names.

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Webb assembled for the first time

Northrop Grumman engineers have successfully completed, for the first time, the full assembly of the James Webb Space Telescope.

To combine both halves of Webb, engineers carefully lifted the Webb telescope (which includes the mirrors and science instruments) above the already-combined sunshield and spacecraft using a crane. Team members slowly guided the telescope into place, ensuring that all primary points of contact were perfectly aligned and seated properly. The observatory has been mechanically connected; next steps will be to electrically connect the halves, and then test the electrical connections.

…Next up for Webb testing, engineers will fully deploy the intricate five-layer sunshield, which is designed to keep Webb’s mirrors and scientific instruments cold by blocking infrared light from the Earth, Moon and Sun. The ability of the sunshield to deploy to its correct shape is critical to mission success.

Only a decade late and nine times over budget ($1 billion vs $9 billion). Let us all pray that when this spacecraft finally reaches its operational location a million miles from Earth it operates as designed.

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Astronomers find Jupiter-sized exoplanet with comet-like orbit

Worlds without end: Astronomers have discovered a Jupiter-sized exoplanet with an extremely eccentric and comet-like orbit circling a star about 103 light years away.

Astronomers have discovered a planet three times the mass of Jupiter that travels on a long, egg-shaped path around its star. If this planet were somehow placed into our own solar system, it would swing from within our asteroid belt to out beyond Neptune. Other giant planets with highly elliptical orbits have been found around other stars, but none of those worlds were located at the very outer reaches of their star systems like this one.

This discovery, like so many others, illustrates again our lack of knowledge about the make-up and formation of solar systems. According to modern formation theories, you shouldn’t get such a large exoplanet in such an eccentric orbit. But here we are.

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Arecibo gets $19 million NASA research/education grant

The Arecibo Observatory in Puerto Rico was today awarded an $19 million NASA research/education grant for studying near Earth asteroids.

NASA awarded the University of Central Florida (which manages the site on behalf of National Science Foundation) the four-year grant to observe and characterize near-Earth objects (NEO) that pose a potential hazard to Earth or that could be candidates for future space missions.

…The award also includes money to support STEM education among high school students in Puerto Rico. The Science, Technology And Research (STAR) Academy brings together 30 local high-school students per semester once a week for 16 classes to learn about science and research at the observatory.

This, plus the recent NSF grant, will keep the telescope operating for at least the next few years.

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China successfully tests navigation in space using pulsars

Using the X-ray space telescope Insight it launched in 2017, China has successfully tested an autonomous navigation system using pulsars.

The time interval of two adjacent pulses emitted by the pulsar is constant. If a spacecraft moves toward the pulsar, the received pulse interval will be shortened, and vise versa. Thus the observed pulse profile will change as the spacecraft moves in space. The relative arrival times of pulses also indicate the relative position of the spacecraft with respect to the pulsar. Therefore, by analyzing the characteristics of the pulsar signals received by the spacecraft, the three-dimensional position and velocity of the spacecraft can be determined, Zheng explained.

From Aug. 31 to Sept. 5, 2017, Insight observed the Crab pulsar for about five days to test the feasibility of pulsar navigation. The research team had also proposed an algorithm for X-ray pulsar navigation, according to Zhang Shuangnan, lead scientist of the Insight space telescope.

The research team further improved the algorithm and applied it in the processing of the observation data of the three detectors onboard Insight. The satellite’s orbit was determined successfully, with the positioning accuracy within 10 km, comparable to that of a similar experiment conducted on the International Space Station, Zhang said.

This is not the first such test. U.S. scientists did something similar using an X-ray telescope on ISS in 2017.

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Data suggests Earth-sized exoplanet has no atmosphere and resembles Mercury

Using archive data from the Spitze Space Telescope astronomers believe that an Earth-sized exoplanet about 49 light years away probably has no atmosphere and is likely similar to Mercury.

Discovered in 2018 by NASA’s Transiting Exoplanet Satellite Survey (TESS) mission, planet LHS 3844b is located 48.6 light-years from Earth and has a radius 1.3 times that of Earth. It orbits a small, cool type of star called an M dwarf – especially noteworthy because, as the most common and long-lived type of star in the Milky Way galaxy, M dwarfs may host a high percentage of the total number of planets in the galaxy.

…The Spitzer observations rule out an atmosphere with more than 10 times the pressure of Earth’s. (Measured in units called bars, Earth’s atmospheric pressure at sea level is about 1 bar.) An atmosphere between 1 and 10 bars on LHS 3844b has been almost entirely ruled out as well, although the authors note there’s a slim chance it could exist if the stellar and planetary properties were to meet some very specific and unlikely criteria. They also argue that with the planet so close to a star, a thin atmosphere would be stripped away by the star’s intense radiation and outflow of material (often called stellar winds).

For a planet to be in the habitable zone of a M dwarf it must orbit very close to the star. This research suggests that conditions that close to the star might still preclude the possibility of life.

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Second gas giant found orbiting Beta Pictoris

Astronomers today announced that they have detected another exoplanet orbiting the young star Beta Pictoris 63 light years away.

This time, the team had to analyse more than 10 years of high-resolution data, obtained with the HARPS instrument at ESO’s La Silla Observatory in Chile, in order to indirectly detect the presence of β Pictoris c. This second giant planet, which has a mass nine times that of Jupiter, completes its orbit in roughly 1,200 days, and is relatively close to its star (approximately the distance between the Sun and the asteroid belt, whereas β Pictoris b is 3.3 times more distant).

Because Beta Pictoris has a very large disk of material, astronomers have expected to find exoplanets there for decades. Only in the last two decades have their instruments improved enough to allow the detections. Moreover, because the star is young, astronomers believe it gives them a glimpse into what our solar system looked like during its early formation period.

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