Tag: astronomy

Astronomers find exoplanet twin of Jupiter

4:03 pm

Worlds without end: Astronomers have discovered an exoplanet with the same mass as Jupiter orbiting its star in a very similar orbit.

Not only that, but:

The planet’s host, the solar twin HIP 11915, is not only similar in mass to the Sun, but is also about the same age. To further strengthen the similarities, the composition of the star is similar to the Sun’s. The chemical signature of our Sun may be partly marked by the presence of rocky planets in the Solar System, hinting at the possibility of rocky planets also around HIP 11915.

I immediately wonder if this star also has rocky inner planets.

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Road to Mauna Kea opened, with restrictions

9:59 am

The University of Hawaii has reopened the road to the summit of Mauna Kea, subject to the emergency restrictions imposed by Hawaii’s Board of Land and Natural Resources.

The visitors center remains closed, and access by the public is much more limited. However, with the road open to employees it means astronomy can resume on the mountain as well as construction of the Thirty Meter Telescope.

I fully expect some of the protesters to defy these restrictions and get arrested. Based on their behavior these past four months, they don’t have much respect either for the law, or for the sacredness of the mountain.

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Hawaii officials vote to limit access to Mauna Kea

6:08 pm

Hawaii’s Board of Land and Natural Resources voted 5 to 2 on Friday to restrict access to Mauna Kea.

The rule restricts being within a mile (1.6 kilometres) of the mountain’s access road during certain nighttime hours, unless in a moving vehicle, and prohibits camping gear. It would allow construction to resume on the $1.4 billion Thirty Meter Telescope, the subject of months of protests. Many Native Hawaiians consider the mountain sacred. Camping was already prohibited on the mountain. “We need the tools to keep order on the mountain,” said board member Chris Yuen. “It’s sad that it has come to this point.”

Not surprisingly, the leader of the protesters said they would ignore the rule and continue their overnight protests.

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The incivility and hostility of the Mauna Kea protesters

11:07 am

The management of Mauna Kea has released event logs by both their rangers [pdf] and the visitor center [pdf], outlining the generally hostile and illegal behavior of the TMT protesters during the past four months, including threats of violence against visiters and workers to the mountain.

The news story above does not really give the full flavor of the protesters’ generally rude and hostile behavior. They repeatedly threatened workers and visitors, damaged both existing facilities as well as the natural environment on which they camped illegally, and interfered with others who had come to the mountain to star-gaze or work. The logs also include numerous examples of the protesters exhibiting incredible ignorance about the astronomy on the mountain as well as the Thirty Meter Telescope itself. If you get the chance, read these logs yourself. They clarify for everyone which side stands on the side of civilization and which does not.

Finally there is this important tidbit:

From March 24, 2015 through present, groups of protesters, some up to nearly 200 persons, have sporadically been onsite on the University of Hawaii management lands and DLNR lands on Maunakea. A group of about 10 protesters has maintained a continuous presence day and night. [emphasis mine]

As is usual for protests like this, the actual numbers are miniscule, and are magnified by a press that wants to promote the protesters’ agenda, even though a very large majority does not agree with that agenda.

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A bullseye in space

11:18 am

Cool image time! The science team of the Swift space telescope has released a movie compiled from X-ray images taken of the first outburst from black hole V404 Cygni in 26 years. [link fixed!]

Astronomers say the rings result from an “echo” of X-ray light. The black hole’s flares emit X-rays in all directions. Dust layers reflect some of these X-rays back to us, but the light travels a longer distance and reaches us slightly later than light traveling a more direct path. The time delay creates the light echo, forming rings that expand with time.

Detailed analysis of the expanding rings shows that they all originate from a large flare that occurred on June 26 at 1:40 p.m. EDT. There are multiple rings because there are multiple reflecting dust layers between 4,000 and 7,000 light-years away from us. Regular monitoring of the rings and how they change as the eruption continues will allow astronomers to better understand their nature.

V404 Cygni is located about 8,000 light-years away. Every couple of decades the black hole fires up in an outburst of high-energy light. Its previous eruption ended in 1989.

The animation below the fold is a smaller resolution version of the movie, showing the rings as they expand outward.
» Read more

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Dance of the stars

8:51 am

Astronomers have found a stellar system made up of five stars, two binary systems orbiting each other, with a fifth star orbiting one of the stars in one of the binaries.

Co-author Dr Markus Lohr, from the Open University, told BBC News that these contact binaries were stars that orbit so closely they share an outer atmosphere. The other star pair – a detached binary – has a separation distance of some three million km. The two binaries orbit in the same plane at a distance of 21 billion km.

Follow-up observations of different wavelengths of light coming from the star system uncovered a fifth star, which is linked to the detached binary star. “This is a truly exotic star system. In principle there’s no reason why it couldn’t have planets in orbit around each of the pairs of stars. Any inhabitants would have a sky that would put the makers of Star Wars to shame,” Dr. Lohr said. “There could sometimes be no fewer than five Suns of different brightnesses lighting up the landscape.”

Dr. Lohr is being a bit extravagant. Though planets are a possibility here, I suspect it very unlikely that they are habitable.

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Astronomers propose giant super Hubble replacement

9:52 am

A major university consortium that manages many ground- and space-based telescopes has proposed that a new giant optical space telescope be built to replace Hubble.

A report published today by the Association of Universities for Research in Astronomy in Washington, D.C., lays out the rationale for another orbiting observatory. It will have a mirror as big as 12 meters across, to both look for habitable planets around other stars and peer deep into the early aeons of the universe.

Hubble has a mirror 2.4 meters across, so this would be significantly larger. In fact, if built this new space telescope would make it bigger than any ground-based telescope that exists today.

As the article notes, the cost over-runs and delays of the infrared James Webb Space Telescope — which went from a $1 billion budget to $8 billion — will likely make Congress reluctant to fund a new giant project like this. Nonetheless, this report gives us a hint of where the astronomy community wants to head in future decades. For the past two decades they have poo-pooed the construction of a new and larger optical space telescope. It appears from this report that this culture is now changing.

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TMT protesters complain about road closure

9:59 am

The leader of the protest that is opposing the construction of the Thirty Meter Telescope (TMT) is now complaining about the road closure imposed by Hawaii’s government that is preventing him and his followers from returning to the mountain.

“The telescope employees have been able to access the mountain every single day to go up and come back down and even we as protectors of the mountain have been given daily access to conduct pule and religious practices on the mountain,” said Kahookahi Kanuha, a member of Ku Kia’i Mauna, which hopes to keep the telescope from being built. “So, if they do deem it unsafe, it is quite irresponsible of them to allow other individuals up the mountain.”

So let me get this straight: He thinks it is wrong for the people who own or lease the mountain — who have legal right to control access — to block the protesters, but he sees nothing wrong with him going there — trespassing — and blocking access to others. What a hypocrite.

This article proves that my analysis from Tuesday is correct. The government has shut the road mainly to quietly get the protesters out of the way and let things cool down. When construction resumes, I guarantee that road access will restricted to prevent the protesters from returning and blocking the road. (Update: The quotes here from the state’s attorney general provide even further confirmation that the state will not allow protests to obstruct future access to construction crews.)

One other note: The author of the first article above uses the typical dishonest mainstream media technique of only quoting one protester, the activist leader, while claiming that “protesters” are objecting. The data in the article, however, does not document this spin. As far as I can tell, the only one complaining about the road closure is this one guy.

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Road to Mauna Kea to remain closed for the rest of the week

10:22 am

The University of Hawaii, which manages the astronomy facilities on top of Mauna Kea, said today that the road to the summit will remained closed for at least the rest of this week so that they can do repairs and maintenance resulting from the protests last week.

I think I finally understand what is going on, and why the protesters themselves offered last week to remove the boulder barricades they had built, something that had not made sense to me at the time.

Because of landslides and the hostile environment, the road needs constant maintenance. The barricades prevented that, which gave the governor and the University the justification to shut the road. And by shutting the road, the University has essentially locked the protesters out. I am sure that the repairs could be done much faster, but the University is probably dragging its feet to make sure they get all the protesters out and things cool down. When the reopen the road, I expect them to make sure it is secure and only official personal use it.

This is why the protesters suddenly offered to remove the barricades. They realized that they had shot themselves in the foot, and wanted to remedy the situation in a way that would allow them to continue protesting. It appears they have failed.

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Hawaii governor condemns protesters

9:40 am

Pigs fly! The liberal Democratic governor of Hawaii today strongly condemned the protesters against the Thirty Meter Telescope (TMT) for blocking the roads to Mauna Kea and made it clear that his administration will do what is necessary to prevent that from happening again.

To quote his statement:

“We expected there to be a protest when construction resumed, and there was. We hoped we would not have to arrest people but were prepared to do so, and we did when they blocked the roadway. We also saw, in what amounts to an act of vandalism, the roadway blocked with rocks and boulders. We deployed to remove the rocks and boulders, but the protesters wisely chose to remove them themselves. And then we saw more attempts to control the road. That is not lawful or acceptable to the people of Hawai‘i. So let me be very direct: The roads belong to all the people of Hawai‘i and they will remain open. We will do whatever is necessary to ensure lawful access.”

Forgive my cynicism and hostility to the Democratic governor. In my experience, it is rare for a Democrat to actively oppose liberal protesters such as these. Normally, Democrats encourage their misbehavior, and do what they can to aid them. For example, in Ferguson, Missouri Democrat governor Jay Nixon intentionally delayed calling out the National Guard in order to allow the riots to continue. Similarly, the Democratic mayor of Baltimore intentionally restrained the police in order to allow the demonstrators, in her own words, “space to destroy”. And then there was the entire Occupy Wall Street protests, all of which trespassed illegally in Democratically controlled urban areas. In every case, there trespass was allowed, and even applauded, by Democrats.

David Ige however has made it clear that he will no longer tolerate any blockage of the road to Mauna Kea, and will do what is necessary to allow the legally agreed construction of the the TMT to go forward. Hooray for him!

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Black hole awakes after 26 years

10:44 am

For the first time since 1989, the black hole in V404 Cygni, a system comprising a black hole and a star, has reawakened, suddenly emitting high energy outbursts beginning on June 15.

First signs of renewed activity in V404 Cygni were spotted by the Burst Alert Telescope on NASA’s Swift satellite, detecting a sudden burst of gamma rays, and then triggering observations with its X-ray telescope. Soon after, MAXI (Monitor of All-sky X-ray Image), part of the Japanese Experiment Module on the International Space Station, observed an X-ray flare from the same patch of the sky.

These first detections triggered a massive campaign of observations from ground-based telescopes and from space-based observatories, to monitor V404 Cygni at many different wavelengths across the electromagnetic spectrum.

The outbursts are probably occurring because the black hole is gobbling up material that has fallen into it.

While the 1989 outburst helped astronomers gain their first understand of the behavior of a black hole in a star system, this outburst will help them understand how such systems evolve and change over time.

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Hawaii governor halts TMT construction again

9:30 am

In a very vague statement the governor of Hawaii has once again stopped construction of the Thirty Meter Telescope (TMT) while he reassesses the situation after protesters yesterday blocked the road to the mountain summit with boulders.

“We are disappointed and concerned that large boulders were found in the roadway leading to the summit of Mauna Kea,” McCartney said in the statement. “This action is a serious and significant safety hazard and could put people at risk. “Because of this, we are making an assessment to determine how to proceed,” he said. “We will be working to clear the roadway tomorrow. Therefore, construction is on hold until further notice.”

The statement implies that he is trying to figure out a way to prevent the protesters from blocking the road, without causing more conflict. I instead suspect he sympathies with the protesters, and is looking for a way to stop construction, which he legally cannot do.

If the road is not reopened by the end of this week and construction is still blocked, I think the TMT managers, as well as the operators of the other telescopes on the mountain, should seriously consider moving from Hawaii. I also repeat that a boycott of Hawaiian tourism might also be appropriate now. This is what these nativist activists want, no more outsiders. We should give them what they want.

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Construction crews turned back by protesters at Mauna Kea

10:34 pm

Despite an announcement that construction of the Thirty Meter Telescope on the summit of Mauna Kea would resume today, construction crews turned back when faced with protesters who blocked the road at 10,000 foot elevation.

The protesters, who number about 200, left the road when police asked them to, then regrouped further up the road. The caravan came to an abrupt stop at the 10,000-foot level at about 12:30 p.m. because protesters had placed boulders in the road, blocking the vehicles.

Andre Perez, a Hawaiian activist and teaching assistant at the University of Hawaii at Manoa, was among the protesters arrested at about 11:30 a.m. “We have a human right to control our land. This is not American land,” Perez said as police took him away.

The first arrest happened at 8:39 a.m. and police arrested more people as the protest moved up the mountain. [emphasis mine]

First, I want to know exactly when this activist purchased the land, since he claims he has the right to control it. Second, what right does he have to rank himself above everyone else in this matter? Does he consider native Hawaiians superior to non-natives? If so, isn’t that somewhat racist and bigoted?

Finally, based on his own words above I think the activist revealed the true hatred that fuels his actions (as well as his fellow protesters). He really doesn’t care about the mountain’s sacredness. He simply hates the United States and wants to destroy it.

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Astronomers have discovered an exoplanet smaller than Earth

11:45 am

Worlds without end: Scientists have measured the size and mass of the smallest exoplanet yet, a Mars-sized planet orbiting a star about 200 light years away.

The planet, named Kepler-138 b, is the first exoplanet smaller than the Earth to have both its mass and its size measured. It is one of three planets that orbit the star Kepler-138 and that pass in front of it on every orbit as viewed from Earth — a maneuver that astronomers call a transit. “Each time a planet transits the star, it blocks a small fraction of the star’s light, allowing us to measure the size of the planet,” said Dr. Daniel Jontof-Hutter, a research associate in astronomy at Penn State who led the study.

“We also measured the gravity of all three planets, using data from NASA’s Kepler mission, by precisely observing the times of each transit,” Jontof-Hutter said. The astronomers also were able to measure the masses of these planets. “Each planet periodically slows down and accelerates ever so slightly from the gravity of its neighboring planets. This slight change in time between transits allowed us to measure the masses of the planets,” Jontof-Hutter explained. After measuring both the mass and size of an exoplanet, astronomers then can calculate its density and its bulk composition.

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New close-up image of Ceres’s double bright spots

9:32 am

close-up of Ceres's bright spots

Cool image time! The Dawn science team has released a some new close-up images of Ceres, including a much higher resolution image of the dwarf planet’s double bright spot, which now resolves itself into a cluster of two larger spots with a half dozen smaller spots scattered nearby.

The region with the brightest spots is in a crater about 55 miles (90 kilometers) across. The spots consist of many individual bright points of differing sizes, with a central cluster. So far, scientists have found no obvious explanation for their observed locations or brightness levels.

“The bright spots in this configuration make Ceres unique from anything we’ve seen before in the solar system. The science team is working to understand their source. Reflection from ice is the leading candidate in my mind, but the team continues to consider alternate possibilities, such as salt. With closer views from the new orbit and multiple view angles, we soon will be better able to determine the nature of this enigmatic phenomenon,” said Chris Russell, principal investigator for the Dawn mission based at the University of California, Los Angeles.

To my eye, these bright areas resemble a wide flat caldera of a volcano. Instead of being at the top of a peak, the caldera is like a lava pool, almost like a large lake. In this case, the large spots are lakes of frozen ice that periodically melt and flow. The smaller spots are likely smaller vents where water can bubble up from below during active periods. When not active, the water will be frozen. Since ice is white and Ceres is very dark, the pools and vents appear extremely bright in these images.

I am speculating however. We will have to wait for much better images to know for sure.

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Hole in observatory door was not caused by bullet

10:26 am

Curiouser and curiouser: In a statement to the press the Subaru Telescope has said that the hole in its door was not caused by a bullet this past weekend but has been known about for months and was caused by wind banging the door against a piece of equipment.

But on Monday, the observatory said in a statement the hole was caused by strong wind swinging a metal door into an instrument fixture attached to a wall. “We at Subaru Telescope are relieved that this is the case and regret the confusion caused by earlier reports,” the statement said.

A detective investigated Monday and determined the hole from the bolt on the wall was there about six months, police said. The observatory’s statement says the day crews knew about the hole from a severe winter storm earlier this year. The observatory didn’t immediately explain why someone reported it to police Saturday night.

The contradictions between the story released today and what was revealed yesterday is quite stark. My guess would be that someone at the telescope, unaware of the hole previously, saw it this weekend and panicked, thinking it caused by a bullet and fearful because of the illegal presence of protesters on the road to the mountain. It is also possible that someone at the telescope saw the hole for the first time and wanted to smear the demonstrators. It is also possible that the rumor was spread by a demonstrator who wanted to smear the astronomers, knowing that the false story would be quickly uncovered.

I could speculate for hours, pointlessly. The bottom line is that the lack of good will from the demonstrators is successfully spreading the ill will to all sides.

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Bullet hole found in Mauna Kea observatory

10:20 am

Even as protesters continue to block the roads to the top of Mauna Kea to prevent construction of the Thirty Meter Telescope (TMT), workers at the Subaru Telescope at the mountain have reported a bullet hole in one door that had been put there sometime over the weekend.

No one knows who did it, or even if the hole was caused by a bullet, though that is what it looks like. The leader of the protests has of course denied any participation and condemned it.

I found this quote from the first link above (which spends a lot of time describing the heroic protesters who have been camping on the road) to be very revealing about this whole affair:

In an email Saturday, DLNR spokeswoman Deborah Ward said the area is not permitted for camping but did not respond to the Tribune-Herald’s questions about why the department has allowed the protesters to remain at the site. “Both state and county officials are monitoring the situation,” she wrote.

Gee, don’t we all remember how government officials turned a blind eye to tea party protests? Not! They did however allow illegal trespassing for Occupy Wall Street. In all these cases, the government officials reveal whose side they are on.

I personally think the astronomy community should organize a boycott of tourism to Hawaii. If their island is so sacred that outsiders shouldn’t be there, maybe we should hold them to their word. We would then find out how serious they really are about the island’s sacredness.

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Hawaii’s highest court takes on TMT case

8:54 am

In a move that appears to be a victory for the protesters trying to shut down the construction of the Thirty Meter Telescope on Mauna Kea, Hawaii’s supreme court on Friday agreed to bypass lower court procedures and immediately consider the case.

It is even possible the court could rule that it is inappropriate to have any telescopes on Mauna Kea.

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Pluto’s moons rotate chaotically

12:33 pm

Data from the Hubble Space Telescope has determined that two and maybe more of Pluto’s moons have chaotic rotations.

In a surprising new study, it has been found that two of Pluto’s moons, Nix and Hydra, are in a chaotic rotation. This means that an observer on Pluto would not see the same face of the moons from one night to the next. For visitors on the moons themselves, things would get even more confusing, as every day would be a different length to the one that preceded it. The other two moons studied, Kerberos and Styx, will likely be found to be chaotic too, pending further study.

This would also mean that you would not know where on the horizon the sun or Pluto would rise each day.

This information was gathered partly to help New Horizons prepare for its July 14 fly-by.

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Astronomers accept terms imposed on them by protesters in Hawaii

5:40 pm

The University of Hawaii, which manages the astronomy operation on Mauna Kea, has accepted the terms laid down by the state’s governor for allowing construction of the Thirty Meter Telescope.

Essentially the number of telescopes on the peak will have to be reduced above and beyond the original decades-old agreement, and the University will have to find money to pay for these “native” programs:

Improved cultural research, education and training: We will work with Kahu Kū Mauna and other Native Hawaiian advisors to develop new cultural training and educational programs about Maunakea. Training is currently required for people working on the mountain and we will look for opportunities for improvement. We will develop training and education programs for visitors to ensure that all who come to Maunakea understand its cultural significance and how to respect the mountain. To ensure our cultural training and education programs are accurate, effective and continuing, we will establish at UH Hilo a new program to lead and evaluate our expanded cultural stewardship and educational activities related to Maunakea. …

New scholarship programs: The governor asked TMT to increase its support to Native Hawaiian students, particularly those from Hawaiʻi Island, who wish to pursue science and technology careers. UH recognizes its responsibilities in this area and we will launch a campaign for new scholarship programs for Hawaiʻi Island and Native Hawaiian students to increase their participation in the sciences. The university will allocate a portion of its observing time to UH Hilo for use in projects and programs to support greater participation and improved preparation of Hawaiʻi Island students for professional careers.

The first will essentially buy off the leaders of the protesters, hiring them to pound into outsiders the wonderfulness of native culture. The second, though it will provide educational scholarships — a good thing — is still essentially bigoted and discriminatory in that it determines who shall get the scholarships solely by their ethnic origin. Imagine the reaction if a university in the U.S. offered a comparable scholarship only to whites.

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ALMA detects a solar flare on Mira 420 light years away

9:17 am

Mira A and Mira B

The just completed ALMA (Atacama Large Millimeter/submillimeter Array), a collection of 66 antennas located in Chile, has snapped a picture of the variable star Mira with its companion star, detecting details on the primary’s surface, including evidence of a solar flare.

Mira is a star with a mass like our Sun’s, but near the end of its life having evolved into a red giant that is shedding its outer layers. Being able to track its behavior with this kind of detail will allow astronomers to better hone their theories about the life and death of stars, including our own.

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A solar system like our own, but when it was a baby

9:28 am

Astronomers have discovered a very young 15 million year old star only 360 light years away that has a debris disk about the size of our solar system’s Kuiper Belt.

The ring is about the same distance from its parent star as the Kuiper belt is from the Sun, and receives roughly the same amount of light. Its blue-grey colour hints that it could consist of ices and rocky silicates such as those found in the Kuiper belt, says lead author Thayne Currie, an astronomer at the Subaru Telescope in Hawaii, which is run by the National Astronomical Observatory of Japan. “This is absolutely the closest example we have of a young Kuiper belt,” he says.

The best part of this discovery however might be how it was made, by using a new instrument on the ground-based Gemini telescope on Mauna Kea in Hawaii.

The instrument, which is part of the Gemini South telescope in Chile, uses a disk called a coronagraph to blot out the glare of bright stars. That allows it to take multi-wavelength pictures of faint, orbiting planets and debris disks around stars, by recording near-infrared light from the parent star as it scatters off the debris. The researchers discovered the disk around HD 115600 fewer than 6 months after the GPI began operation. A similar instrument, known as SPHERE, began operating in May 2014 on the European Southern Observatory’s Very Large Telescope in Chile and has also begun to make discoveries.

Assuming protesters don’t force Gemini to close, we should be getting a lot more exoplanetary discoveries from it in the coming years.

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Hubble films of movie of a jet firing from a black hole

12:38 pm

Cool image time! Using images taken by the Hubble Space Telescope over the past two decades astronomers have assembled a movie of the motion of blobs, ejected by a jet from a supermassive black hole at the center of a galaxy.

The jet from NGC 3862 has a string-of-pearls structure of glowing knots of material. Taking advantage of Hubble’s sharp resolution and long-term optical stability, Eileen Meyer of the Space Telescope Science Institute (STScI) in Baltimore, Maryland, matched archival Hubble images with a new, deep image taken in 2014 to better understand jet motions. Meyer was surprised to see a fast knot with an apparent speed of seven times the speed of light catch up with the end of a slower moving, but still superluminal, knot along the string. The resulting “shock collision” caused the merging blobs to brighten significantly.

The movie is below the fold.
» Read more

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Hawaii’s governor imposes new deal for Mauna Kea

10:29 am

In his effort to appease the protesters hostile to building the Thirty Meter Telescope (TMT) on Mauna Kea, Hawaii’s Democratic governor has thrown out the decades-old agreement that had guided telescope construction there and has instead imposed a new deal, which will allow for TMT but will force astronomers to remove one quarter of the other telescopes on the mountain.

Astronomers have always honored the original agreement, allowing the construction of no more than 13 telescopes on the mountain. For example, to build TMT the Caltech Submillimeter Observatory was to be removed this year. Now they will have to remove some additional telescopes that had been built with the understanding that they could remain there, based on the original agreement.

The governor’s plan will also limit access to the mountain by non-natives, and require visitors to receive “cultural training”, likely a session explaining the sacredness of the native religion and how it must be obeyed at all times.

To my mind this new deal is another indication of the slow retreat of western civilization in the U.S. Once again our ability to push the unknown will be limited in favor of fostering the superiority of one ethnic group over another.

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Prototype variable star has a previously unknown companion

10:51 am

The uncertainty of science: The star that gave its name to the class of variable stars called Cepheid variables — used by astronomers to measure distances to nearby galaxies — has after more than 200 years of study been suddenly found to be a binary system.

Delta Cephei, prototype of the cepheids, which has given its name to all similar variable stars, was discovered 230 years ago by the English astronomer John Goodricke. Since the early 20th century, scientists have been interested in measuring cosmic distances using a relationship between these stars’ periods of pulsation and their luminosities (intrinsic brightness), discovered by the American Henrietta Leavitt. Today, researchers from the Astronomical Observatory of UNIGE, Johns Hopkins University and the ESA show that Delta Cephei is, in fact, a double star, made up of a cepheid-type variable star and a companion that had thus far escaped detection, probably because of its low luminosity. Yet, pairs of stars, called binaries, complicate the calibration of the period-luminosity relationship, and can bias the measurement of distances. This is a surprising discovery, since Delta Cephei is one of the most studied stars, of which scientists thought they knew almost everything. [emphasis mine]

This discovery illustrates the shaky foundation of a great deal of astronomical research. The presence of a companion is an additional variable that could very significantly skew the relationship between the stars’ pulses and its luminosity, thus making the use of this data to determine distance much less reliable. This in turn could have a significant effect on the present estimate of the expansion rate of the universe, which in turn could have a significant effect on the theories of dark energy. Moreover, if the past distance estimates to many objects are wrong than what we know about those objects is far less certain.

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Mysterious X-rays at the center of the galaxy

9:07 am

The uncertainty of science: The x-ray space telescope NuSTAR has detected high energy x-rays at the center of the Milky Way coming from no obvious source.

In and of themselves, X-rays from the galactic center aren’t unusual. But the X-rays NuSTAR detects don’t seem to be associated with structures already known to exist. For example, a supernova remnant named Sgr A East emits low-energy X-rays but not high-energy X-rays. The high-energy blotch doesn’t correlate with structures seen in radio images either, such as the dust and gas clouds of Sgr A West that are falling toward the supermassive black hole.

Instead, Perez and her colleagues propose that thousands of stellar corpses could be responsible for the high-energy X-rays: massive (and still-growing) white dwarfs, spun-up pulsars, or black holes or neutrons stars feeding on low-mass companion stars.

All of their proposed solutions, however, have serious problems explaining all of the data.

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An exoplanet that shouldn’t exist

10:06 am

Worlds without end: Astronomers have discovered an exoplanet that is too big for its tiny host star.

Present theory says that a Jupiter-sized planet should not have formed around this M-class dwarf star. But it has. In addition, the planet has the mass of Saturn but has been puffed up to the size of Jupiter. Yet, the star doesn’t provide it enough heat to cause it to puff up in this manner.

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