China still struggling to find scientists to run FAST radio telescope

8:32 am

China is still finding it difficult to hire the scientists necessary to run its FAST radio telescope, the largest single dish radio telescope in the world.

And why is that?

For job candidates, the major stumbling blocks often are financial incentives and research independence, researchers told the South China Morning Post. The telescope’s remote location also may give candidates pause.

George Smoot, a Hong Kong University of Science and Technology professor who won the Nobel Prize in physics in 2006, said candidates interested in working in a more developed setting might think twice about spending a lot of time in an area known for its traditional rural villages.

“Another issue is how much the Chinese Academy of Sciences will influence and direct activities there,” Smoot said. “It is an issue to people unless they have some straight link.” [emphasis mine]

It must always be remembered that nothing in China is done without the government’s approval. For western astronomers, used to having a great deal of independence, this fact makes working there somewhat unappealing.

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Genesis cover

On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.

 

The print edition can be purchased at Amazon, any other book seller, or direct from my ebook publisher, ebookit. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, free with a 30-day trial membership to Audible.
 

"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News

Oumuamua might be artificial lightsail

3:45 pm

A new analysis of the velocity and path of the interstellar object Oumuamua suggests it might be an artificial lightsail.

The study, which was posted online earlier this month, suggests that Oumuamua’s strange “excess acceleration” could be artificial in nature, as it has been implied that it is not an active comet. “Considering an artificial origin, one possibility is that ‘Oumuamua is a lightsail, floating in interstellar space as a debris from an advanced technological equipment,” researchers wrote in the paper.

The paper continues: “Lightsails with similar dimensions have been designed and constructed by our own civilization, including the IKAROS project and the Starshot Initiative. The lightsail technology might be abundantly used for transportation of cargos between planets or between stars.”

They even theorized that Oumuamua “may be a fully operational probe sent intentionally to Earth vicinity by an alien civilization,” though that scenario was called “exotic.”

All of this is speculation. However, that the object is moving faster than expected, based on the initial data of its path, is quite intriguing. The authors of the paper concluded that the excess speed was caused by “solar radiation pressure.” They also calculated that for the light pressure to cause that increase in speed as it moves away requires it to have a large surface area.

The observations are not sufficiently sensitive to provide a resolved image of ‘Oumuamua, and one can only speculate on its possible geometry and nature. Although periodic variations in the apparent magnitude are observed, there are still too many degrees of freedom (e.g., observing angle, non-uniform reflectively, etc.) to definitely constrain the geometry. The geometry should not necessarily be that of a planar sheet, but may acquire other shapes, e.g., involving a curved sheet, a hollow cone or ellipsoidal, etc. Depending on the geometry our estimated value for the mass-to-area ratio will change, but the correction is typically of order unity.

They then speculate the possibility of the object being an interstellar probe.

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Conscious Choice cover

Now available in hardback and paperback as well as ebook!

 

From the press release: In this ground-breaking new history of early America, historian Robert Zimmerman not only exposes the lie behind The New York Times 1619 Project that falsely claims slavery is central to the history of the United States, he also provides profound lessons about the nature of human societies, lessons important for Americans today as well as for all future settlers on Mars and elsewhere in space.

 
Conscious Choice: The origins of slavery in America and why it matters today and for our future in outer space, is a riveting page-turning story that documents how slavery slowly became pervasive in the southern British colonies of North America, colonies founded by a people and culture that not only did not allow slavery but in every way were hostile to the practice.  
Conscious Choice does more however. In telling the tragic history of the Virginia colony and the rise of slavery there, Zimmerman lays out the proper path for creating healthy societies in places like the Moon and Mars.

 

“Zimmerman’s ground-breaking history provides every future generation the basic framework for establishing new societies on other worlds. We would be wise to heed what he says.” —Robert Zubrin, founder of the Mars Society.

 

All editions are available at Amazon, Barnes & Noble, and all book vendors, with the ebook priced at $5.99 before discount. All editions can also be purchased direct from the ebook publisher, ebookit, in which case you don't support the big tech companies and the author gets a bigger cut much sooner.

 

Autographed printed copies are also available at discount directly from the author (hardback $29.95; paperback $14.95; Shipping cost for either: $6.00). Just send an email to zimmerman @ nasw dot org.

Sunspot update October 2018: Deepening minimum

9:04 am

The monthly NOAA update of the solar cycle, covering sunspot activity for October 2018, was released yesterday. As I have done every month since this website began in July 2011, I am posting it below, annotated to give it some context.

Though there was a tiny uptick in sunspot activity on the Sun in October, the uptick was inconsequential. Overall, the activity in the past few months appears to closely match the weak activity seen in late 2007 and early 2008, just when the last solar minimum began.

October 2018 sunspot activity

The graph above has been modified to show the predictions of the solar science community. The green curves show the community’s two original predictions from April 2007, with half the scientists predicting a very strong maximum and half predicting a weak one. The red curve is their revised May 2009 prediction.

As I noted in August, the NOAA graph is now getting very close to its right edge, which ends in December 2018. They will very soon have to update this graph so that it can take us into the next solar cycle. While they must do this, it will unfortunately end the standard visual used by them for more than a decade for showing the progress of the solar cycle. Depending on how they change it, I might be able adapt it to include this graph to allow a continuation of the same visual into the future. We will have to see.

Having seen now the full solar maximum for this cycle (weak and short), we are now moving to the next question: Will the developing solar minimum be as long and as deep as the last? Will it evolve into a grand minimum, lasting decades, as some solar scientists believe?

Or will the Sun return to the higher levels of activity seen during most of the 24 solar cycles observed since the last grand minimum in the 1600s?

Since our understanding of these changes is very poor, your guess is likely as good as anyone else’s. All we can really do is keep our eyes open and watch what happens.

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Farrakhan leads “Death to America” chants in Iran

8:25 am

They’re coming for you next: Louis Farrakhan, friend and ally to the Democratic Party and its leadership, this week visited Iran where he led of chants “Death to America” and “Death to Israel.”

Nation of Islam leader Louis Farrakhan led a chant of “Death to America!” on a solidarity visit to Iran this weekend, according to Iranian news sources. He also led a chant of “Death to Israel!”

Farrakhan visited Iran ahead of the renewal of U.S. sanctions against the regime at midnight on November 5. The renewed sanctions are the result of the American withdrawal from the agreement negotiated by the Obama administration, which purported to prevent Iran’s development of nuclear weapons but merely delayed it.

Any vote for any Democrat on election day will essentially be an endorsement of this behavior, as the Democratic Party at all levels for many years has shown strong ties and sympathy for Farrakhan and his brand of bigotry and anti-American hate.

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Leaving Earth cover

Leaving Earth: Space Stations, Rival Superpowers, and the Quest for Interplanetary Travel, can be purchased as an ebook everywhere for only $3.99 (before discount) at amazon, Barnes & Noble, all ebook vendors, or direct from my ebook publisher, ebookit.

 

If you buy it from ebookit you don't support the big oppressive tech companies and I get a bigger cut much sooner.

 

Winner of the 2003 Eugene M. Emme Award of the American Astronautical Society.

 
"Leaving Earth is one of the best and certainly the most comprehensive summary of our drive into space that I have ever read. It will be invaluable to future scholars because it will tell them how the next chapter of human history opened." -- Arthur C. Clarke

Airbus to deliver the first Orion service module to NASA this week

8:44 pm

My heart be still! Airbus will deliver this week the first Orion service module to NASA.

Airbus will deliver the first European Service Module (ESM) for NASA’s Orion spacecraft from its aerospace site in Bremen, Germany on 5 November 2018. An Antonov cargo aircraft will fly the ESM to NASA’s Kennedy Space Center in Florida, USA. This is the result of four years of development and construction, and represents the achievement of a key milestone in the project. ESA selected Airbus as the prime contractor for the development and manufacturing of the first ESM in November 2014.

Four years to simply build a single manned capsule’s service module. At this pace we might be able to colonize Mars and the Moon in about 200 years, maybe!

Note however that NASA only has funding to build 1.5 of these European service modules. It is possible that Congress has allocated additional funds, but if so, I missed it.

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Russia launches another Soyuz, placing GPS-type satellite in orbit

8:39 pm

Russia today successfully placed a Glonass GPS-type satellite in orbit using a variation of its Soyuz rocket.

This is the second launch of a Soyuz since the October 11 manned launch failure. Though both launches used versions different from the October 11 rocket, the first stage strap-on boosters as well as second core stage were the same, providing strong proof that the December manned launch to ISS can go on as planned.

The leaders in the 2018 launch race:

31 China
17 SpaceX
10 Russia
8 ULA
7 Europe (Arianespace)

China still leads the U.S. 31 to 26 in the national rankings.

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Juanita Hall – Bali Ha’i

6:01 pm

An evening pause: From the 1958 movie of the great Rodgers & Hammerstein musical, South Pacific.

I first saw this movie as a child when I was around five years old. I didn’t understand the story really, and was especially puzzled by some lyrics, especially because my young mind took them very literally. (Just consider “I’m going wash that man right out of my hair!”)

What I do remember was that this song became one of my favorites throughout my early childhood. In hearing it recently again, I was struck by something I clearly remember, from that childhood. The song is about the draw of love and desire, which is what Bali Ha’i partly represents. However, Hammerstein’s lyrics refer to more, to the greater magic hidden in life everywhere, the mystery that lies behind the black, you might say. It is a theme he repeated in many of the songs he wrote for Richard Rodgers..

What struck me now was how I clearly remember, as a child of five, being very aware of this second somewhat sophisticated meaning. At first I was a little surprised that a child of five could comprehend such concepts, but then as Wordsworth wrote,

The Soul that rises with us, our life’s star,
Hath had elsewhere its setting,
And cometh from afar:
Not in entire forgetfulness,
and not in utter nakedness,
But trailing clouds of glory do we come
From God, who is our home:
Heaven lies about us in our infancy!

As a child I knew nothing of the sexual draw of Bali Ha’i, but I understood its mystical nature quite naturally. I have since spent my life trying to hold onto those “clouds of glory,” because they help connect us better to the enigma that is existence.

This version uses Juanita Hall’s own voice, from an earlier recording. For the movie they dubbed her singing because Rodgers no longer thought her aging voice sounded right.

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Musk endorses Trump’s Space Force proposal

9:28 am

In a long hour long interview (which you can listen to at the link), Elon Musk endorsed President Trump’s proposal to create a Space Force.

Elon Musk sees a new branch of the U.S. Armed Forces as “obvious” as Americans travel far off the planet. “It’s basically defense in space. And then I think also it could be pretty helpful for maybe expanding our civilization,” Musk told Kara Swisher on a new episode of Recode Decode. “I do think it will become obvious over time that a Space Force is a sensible thing to do.”

Donald Trump pitched the new military operation this year, and hopes to have it running by 2020, bringing the military into conversation with space leaders like NASA and Musk’s SpaceX. It would sit alongside branches like the Army and the Air Force.

Musk described the agency as similar to the Air Force, something he said was criticized as unnecessary when air wars were managed by the Army but which is now a specialized division. “And people today may not realize back then it was wildly penned as a ridiculous thing to create the Air Force, but now everyone’s like, ‘Obviously you should have an Air Force,’” Musk said. “And I think it’s gonna become obvious that we should have a Space Force, too.”

I don’t have time now to listen to the hour-plus-long interview, but it appears Musk talked about other things of interest, making worth one’s time.

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Danish astronomers question gravitational wave detection

9:23 am

The uncertainty of science: A team of Danish astronomers have questioned the gravitational wave detection achieved in the past few years by the LIGO gravitational wave telescopes.

The details are complex and very much in dispute, and the position of these Danish astronomers is very much in the minority, but their doubts have not been dismissed, and illustrate well the best aspects science. The article also outlines how the physics community and the LIGO scientists have welcomed the skepticism, even as they have doubts about the claims of the Danish astronomers. This is the hallmark of good science, and lends weight to the work at LIGO.

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Head of Webb investigation: Webb was “a step too far”

9:11 am

The head of an investigation panel into the James Webb Space Telescope admitted this week that, though he and the panel fully support the telescope’s completion and launch, he also believes the telescope was too ambitious and “a step too far.”

Speaking at a meeting of the Committee on Astronomy and Astrophysics of the National Academies’ Space Studies Board Oct. 29, Tom Young said that while the mission may ultimately be a success, its difficulties provide lessons as NASA considers future large astronomy missions in the next decadal survey.

“I, personally, have come to the conclusion that JWST had too many inventions, too much risk, and was a step too far,” he said at the end of a presentation about the review board’s work.

Young emphasized that he was neither opposed to JWST being completed nor had doubts it could be done successfully. “There are a group people who are diehard supporters of JWST, and there are others who support it, but they’re really angry at the cost growth and the schedule delays,” he said.

You think? Webb was supposed to cost about $500 million, and launch in 2007. Its budget is now almost $10 billion, and it will not launch before 2021. In the process it has destroyed the entire astronomy program at NASA, preventing the construction of any other space telescopes.

The key question is whether the astronomy community or NASA has learned anything from this disaster. I personally am doubtful, since they are still pushing for WFIRST, a similar big boondoggle that will cost billions and is already overbudget and behind schedule, though it is only in its design stage.

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Russians say Soyuz sensor was damaged in manufacture

9:04 am

The Russians yesterday revealed that the sensor they have identified as the cause of the October 11 Soyuz launch failure was damaged during manufacture.

Their response:

Skorobogatov said officials are now taking steps, including putting all assembly staff through competence tests and additional training, to make sure such malfunctions don’t happen again.

The rocket producer will also take apart two other rockets that have been recently assembled and are due to launch in the coming weeks and then re-assemble them, Skorobogatov said.

They do not say how the damage occurred. It also appears that, like all government run operations, no one will be fired. (The Russians only fire people when they are going to criminally indict them.)

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Dawn’s last look at Ceres

10:14 am

Ceres

The Dawn mission has ended, and the image on the right, reduced to post here, is one of its last views of Ceres, with the bright spots of Occator Crater clearly visible, before its fuel ran out. You can see the full resolution image by clicking on the image.

This photo of Ceres and the bright regions in Occator Crater was one of the last views NASA’s Dawn spacecraft transmitted before it depleted its remaining hydrazine and completed its mission.

This view, which faces south, was captured on Sept. 1, 2018 at an altitude of 2,340 miles (3,370 kilometers) as the spacecraft was ascending in its elliptical orbit. At its lowest point, the orbit dipped down to only about 22 miles (35 kilometers), which allowed Dawn to acquire very high-resolution images in this final phase of its mission. Some of the close-up images of Occator Crater are shown here.

Occator Crater is 57 miles (92 kilometers) across and 2.5 miles (4 kilometers) deep and holds the brightest area on Ceres, Cerealia Facula in its center and Vinalia Faculae in its western side. This region has been the subject of intense interest since Dawn’s approach to the dwarf planet in early 2015.

If NASA made any specific announcement about the end of the mission, I have missed it. Either way, this end is not a surprise, because they have made it clear for the past few months that the spacecraft was about to run out of fuel.

They have also posted today an image of Ceres’ largest mountain, Ahuna Mons.

Update: Even as I posted this, NASA sent out this press release: NASA’s Dawn mission comes to an end

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China tests its own grasshopper

10:02 am

China has completed its first vertical rocket landing test, using a prototype small scale first stage very similar to SpaceX’s Grasshopper test rocket.

If I was cynical, I’d say that this isn’t just similar, it is a direct steal from Grasshopper. But then, that is generally how the Chinese have come up with their new technology, not by creating it themselves, but by stealing ideas from others and then upgrading them.

Either way, this test shows that China is devoting serious energy to making its first stages reusable.

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Company focused on cleaning up space junk raises $50 million

9:54 am

Capitalism in space: Astroscale, a Japanese company with British ties, has raised $50 million in investment capital for developing a robot spacecraft for locating and removing space junk from orbit.

The company plans to use the funding to support several ongoing efforts, including the development of a technology demonstration satellite called ELSA-d. That spacecraft, scheduled for launch in early 2020 on a Soyuz rocket, will feature “target” and “chaser” satellites to demonstrate rendezvous and proximity operations. The target spacecraft is being built by British smallsat developer Surrey Satellite Technology Ltd. under a contract announced last November.

The funding will support scaling up an operations center Astroscale established in the United Kingdom in 2017 that also handles engineering, procurement and business development. Astroscale said it plans to establish an office in the United States in 2019.

The article notes also that much of this money comes from Japanese investors, including Mitsubishi, and reflects a growing interest in Japan in private commercial space.

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Planetary Resources bought by blockchain company

9:47 am

Capitalism in space: The so-called asteroid mining company Planetary Resources has now been bought by computer blockchain company.

Planetary Resources said in a statement that it was acquired by ConsenSys, Inc. in an “asset-purchase transaction.” The companies did not disclose specific terms of the agreement. Chris Lewicki, the president and chief executive of Planetary Resources, and Brian Israel, the company’s general counsel, will join ConsenSys as part of the deal.

ConsenSys describes itself as a “blockchain venture production studio focused on building and scaling tools, disruptive startups, and enterprise software products powered by decentralized technology, specifically Ethereum.” Ethereum itself is a decentralized computing platform best known for supporting a cryptocurrency called Ether similar to the better-known bitcoin.

Don’t ask me how ConsenSys makes its money. I haven’t the faintest. I also haven’t the slightest idea what they intend to do with Planetary Resources. I can say without doubt that it won’t be asteroid mining.

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OSIRIS-REx snaps image of target asteroid Bennu

9:41 am

Bennu

OSIRIS-REx has snapped its sharpest image yet of its target asteroid Bennu, set for a rendezvous on December 3. The image on the right is that image, at full resolution but cropped.

This “super-resolution” view of asteroid Bennu was created using eight images obtained by NASA’s OSIRIS-REx spacecraft on Oct. 29, 2018 from a distance of about 205 miles (330 km). The spacecraft was moving as it captured the images with the PolyCam camera, and Bennu rotated 1.2 degrees during the nearly one minute that elapsed between the first and the last snapshot. The team used a super-resolution algorithm to combine the eight images and produce a higher resolution view of the asteroid. Bennu occupies about 100 pixels and is oriented with its north pole at the top of the image.

It is beginning to appear that the OSIRIS-REx engineering team is going to have the same kind of problems now faced by the Hayabusa-2 engineering team. In this first glance Bennu appears very similar to Ryugu, a rubble pile shaped approximately like a box, rotating on one point. If so, they are also going to find it difficult to locate a smooth landing site.

Bennu by the way is in an orbit that makes a collision with the Earth possible in the late 22nd century. Knowing its composition, density, and solidity is critical for determining what to do, should that collision become likely.

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China launches two more GPS-type navigation satellites

9:28 am

Completing its 31st successful launch this year, China today placed two more GPS-type Beidou satellites into orbit, using a Long March 3B/G2 rocket.

The article says this is China’s 32nd launch, but that includes one failure. The leaders in the 2018 launch race:

31 China
17 SpaceX
9 Russia
8 ULA
7 Europe (Arianespace)

China has widened its lead over the U.S. in the national rankings to 31 to 26.

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Russia releases video of October Soyuz launch, showing failed strap-on release

9:17 am

Russia has released video from the outside of its Soyuz rocket during the failed October 11 Soyuz launch, showing one of the rocket’s four strap-on boosters not releasing properly.

The key moment of the video, embedded below, is at 1:25. The booster on the left does not appear to release at its top. The article at the link says the Russians now believe that a failed sensor prevented the opening of a valve that would allow the venting of oxygen to push the booster away.

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Parker begins first perihelion fly-by of Sun

9:10 am

It’s getting hot in here: The Parker Solar Probe has begun its first close orbital fly-by of the Sun, set to last from now until November 11.

This solar encounter encompasses the first perihelion of the mission, the point at which Parker Solar Probe is closest to the Sun. Perihelion is expected at about 10:28 p.m. EST on Nov. 5. The spacecraft will come within 15 million miles of the Sun’s surface and clock in at a top speed of 213,200 miles per hour relative to the Sun — setting new records for both closest solar approach and top heliocentric speed by a spacecraft. At perihelion, Parker Solar Probe will fly through material at about 3.6 million degrees Fahrenheit — but because material in this region is so tenuous, it doesn’t influence the temperature of the spacecraft. However, the Sun’s intense radiation heats the Sun-facing side of the spacecraft’s heat shield, called the Thermal Protection System, to about 820 F.

For several days around the Nov. 5 perihelion, Parker Solar Probe will be completely out of contact with Earth because of interference from the Sun’s overwhelming radio emissions.

The article provides some nice details about the spacecraft’s design.

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October 31, 2018 Zimmerman/Pratt podcast

9:27 pm

Today I sent a half hour with Robert Pratt of Pratt on Texas, doing two segments. In the first segment, available here, we discussed the announcement by SpaceX that it was going to do the first flight tests of its Big Falcon Rocket out of its new spaceport in Boca Chica, Texas.

In the second segment, available here, Robert allowed me to vent about the disgusting behavior of the leftist protesters during a moment of silence for those killed by an anti-Semite in Pittsburgh.

Both are worth listening to, especially the second.

First link fixed!

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The vast northern plains of Mars

3:33 pm

The vast northern plains of Mars

Cool image time! Actually, this image, found in the October image release from the high resolution camera of Mars Reconnaissance Orbiter (MRO), is not that interesting, in its own right. Context is all!

The image on the right is a small section cropped and reduced in resolution from the full image, which you can see by clicking on it. It shows one of the only interesting features in this long image strip, a small mesa sticking out all by itself in a flat featureless plain pockmarked by various small craters.

The release has no caption, though it is entitled “Northern Plains Survey.” The northern plains, while having a lot of interesting features that attract the attention of planetary scientists and thus get photographed at high resolution, is mostly featureless, at least at the resolution of the wide field survey cameras on many Mars orbiters. In order to know what is really there, they need to take high resolution images systematically, of which this image is obviously a part.

Overview image

The problem is that there is so much ground to cover. This particular image was taken of a spot in the middle of the plains just to the north of the drainage outlets from Valles Marineris, as shown by the context map to the right. The tiny white spot to the right in the middle of the blue plains north of those drainage outlets is the location of this image.

Detail area of overview map

To understand how much ground needs to be covered, to the right is a close-up of the area shown by the white box in the first image above, with red rectangles indicating where MRO has already taken images. The white cross is the subject image. As you can see, most of this immense plain has not yet been imaged. It is almost as if they threw a dart to pick this one location. Most everything around it remains unseen at high resolution. Thus, to understand the geology of this one image is hampered because the surrounding terrain remains unknown, in close detail.

Mars is a big place. It is an entire planet, with the same land surface as the Earth’s continents. It still contains many mysteries and unexplored places. It will take generations to see it all.

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Early Milky Way collision uncovered by Gaia

12:21 pm

Data from the space telescope Gaia has revealed a Milky Way merger event that occurred about 10 billion years ago.

Using the first 22 months of observations, a team of astronomers led by Amina Helmi, University of Groningen, The Netherlands, looked at seven million stars – those for which the full 3D positions and velocities are available – and found that some 30,000 of them were part of an ‘odd collection’ moving through the Milky Way. The observed stars in particular are currently passing by our solar neighbourhood.

We are so deeply embedded in this collection that its stars surround us almost completely, and so can be seen across most of the sky.

Even though they are interspersed with other stars, the stars in the collection stood out in the Gaia data because they all move along elongated trajectories in the opposite direction to the majority of the Galaxy’s other hundred billion stars, including the Sun. They also stood out in the so-called Hertzprung-Russell diagram – which is used to compare the colour and brightness of stars – indicating that they belong to a clearly distinct stellar population.

The sheer number of odd-moving stars involved intrigued Amina and her colleagues, who suspected they might have something to do with the Milky Way’s formation history and set to work to understand their origins. In the past, Amina and her research group had used computer simulations to study what happens to stars when two large galaxies merge. When she compared those to the Gaia data, the simulated results matched the observations. “The collection of stars we found with Gaia has all the properties of what you would expect from the debris of a galactic merger,” says Amina, lead author of the paper published today in Nature.

At the time, the two galaxies were both probably about the same size, approximately equivalent to the Magellanic Clouds.

Must I mention that there is some uncertainty here? The data is good, and the conclusions seem quite reasonable. At the same time, the data is still somewhat thin. We need a lot more Gaia-type telescopes mapping out the motions and positions of all the stars of the Milky Way in far more detail before the uncertainties here will shrink.

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Timelapse movie of Supernova 1987A’s evolution from 1992 to 2017

9:42 am

Cool movie time! An astronomy graduate student in Toronto has created a movie showing the steady evolution of the shock wave from Supernova 1987A, the first supernova visible to the naked eye since the discovery of the telescope, during the past twenty-five years.

Yvette Cendes, a graduate student with the University of Toronto and the Leiden Observatory, has created a time-lapse showing the aftermath of the supernova over a 25-year period, from 1992 to 2017. The images show the shockwave expanding outward and slamming into debris that ringed the original star before its demise.

In an accompanying paper, published in the Astrophysical Journal on October 31st, Cendes and her colleagues add to the evidence that the expanding remnant is shaped—not like a ring like those of Saturn’s—but like a donut, a form known as a torus. They also confirm that the shockwave has now picked up some one thousand kilometres per second in speed. The acceleration has occurred because the expanding torus has punched through the ring of debris.

The animation, which I have embedded below the fold, uses images produced by an array radio telescopes in Australia.
» Read more

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Oblique view of Hayabusa-2’s most recent landing rehearsal

9:28 am

Cool movie time! The Hayabusa-2 science team has released a small movie of images taken by a side-mounted camera of the spacecraft’s most recent landing rehearsal, showing the spacecraft ascend from its closest approach from an oblique angle.

I have embedded the movie from these images below the fold. As they note,

Images taken with the small monitor camera (CAM-H) during the Touchdown 1 Rehearsal 3 operation (TD1-R3). One image was captured every second from immediately after the spacecraft began to ascend (altitude 21m) on October 25, 2018 at 11:47 JST. The spacecraft was rising at about 52cm/s.

It appears the closest image was taken from about 21 meters away, about 65 feet, and gives a sense of scale. It also reveals once again how difficult that landing in January is going to be. Though this location is thought to be the smoothest spot on Ryugu, it is still littered with rocks that could cause problems.
» Read more

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