Tag: science

Mountains and craters on Pluto?

9:09 am

The edge of Tombaugh Regio

Cool image time! Even as they download new images for a press conference on Friday, the New Horizons’ science team has released a new close-up of Tombaugh Regio, showing both a new mountain range within it as well as its sharply defined western contact with the dark whale feature, which now appears to be heavily cratered and old.

“There is a pronounced difference in texture between the younger, frozen plains to the east and the dark, heavily-cratered terrain to the west,” said Jeff Moore, leader of the New Horizons Geology, Geophysics and Imaging Team (GGI) at NASA’s Ames Research Center in Moffett Field, California. “There’s a complex interaction going on between the bright and the dark materials that we’re still trying to understand.” While Sputnik Planum is believed to be relatively young in geological terms – perhaps less than 100 million years old — the darker region probably dates back billions of years. Moore notes that the bright, sediment-like material appears to be filling in old craters (for example, the bright circular feature to the lower left of center).

Make sure you click through to see the full resolution image. It is quite astonishing. They have also released a new image each of two of Pluto’s moons.

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Iran’s parliament questioning Iran nuclear deal

11:24 am

Democracy in action! Iran’s parliament is likely to demand changes to Iran deal before voting for its approval.

The ironies here are tragic. While their parliament stands up for its constitutional rights, our Congress, run by Republicans, has ceded its power to the President, with the Senate giving up its constitutional right to only approve treaties with a two-third majority. Instead, they got down on their knees and handed Obama the power to make this very bad treaty without their full consent. What idiots.

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Internet tycoon commits $100 million to alien life search

9:16 am

Russian internet entrepreneur Yuri Milner has given SETI $100 million for a ten year project to accelerate their effort to search for evidence of extraterrestrial life.

Understanding why SETI needs private funding is important:

SETI has been going on since 1960, when radio telescopes became sensitive enough to detect signals from another planet if it was broadcasting signals similar to those which our civilization does. Researchers developed devices that could monitor millions of frequencies at once for any signal that looked at all different from that produced by astronomical objects or the natural background. At first funded by universities and NASA, public funding for SETI was axed by Congress in the early 1990s. Since then, the nonprofit SETI League has received funding of a few million dollars a year from private donors.

Congress correctly cut the funds because it isn’t really the business of the federal government to search for alien life. Some taxpayers really don’t want their money used for that purpose, and they should have the right to say no. Instead, Congress essentially told SETI to do it right: Get private funding from people who want the research done. The work will be done more efficiently for less, and no one will be required to contribute who doesn’t want to.

Milner’s contribution now is the biggest donation yet, and suggests that interest in this research is building culturally.

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Philae status update

9:01 am

Engineers on the Rosetta team are struggling to figure out why they cannot get a solid communications lock with their Philae lander, and have come up with several explanations.

One possible explanation being discussed at DLR’s Lander Control Center is that the position of Philae may have shifted slightly, perhaps by changing its orientation with respect to the surface in its current location. The lander is likely situated on uneven terrain, and even a slight change in its position – perhaps triggered by gas emission from the comet – could mean that its antenna position has also now changed with respect to its surroundings. This could have a knock-on effect as to the best position Rosetta needs to be in to establish a connection with the lander.

Another separate issue under analysis is that one of the two transmission units of the lander appears not to be working properly, in addition to the fact that one of the two receiving units is damaged. Philae is programmed to switch periodically back and forth between these two transmission units, and after tests on the ground reference model, the team has sent a command to the lander to make it work with just one transmitter. As Philae is able to receive and accept commands of this kind in the “blind”, it should execute it as soon as it is supplied with solar energy during the comet’s day.

They have heard from Philae since July 9. Because of comet activity they have had to pull Rosetta back away from the nucleus to protect it, and are now focusing its primary activity on observations, not communications with Philae. They will continue to try to bring Philae back to full functioning life, but the priority is now the comet.

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Dawn resumes descent to Ceres

11:45 pm

After a several week pause while engineers analyzed the issue that caused the spacecraft to go into safe mode on June 30, they have now resumed their descent to a lower orbit to take higher resolution images of Ceres.

The spacecraft experienced a discrepancy in its expected orientation on June 30, triggering a safe mode. Engineers traced this anomaly to the mechanical gimbal system that swivels ion engine #3 to help control the spacecraft’s orientation during ion-thrusting. Dawn has three ion engines and uses only one at a time. Dawn’s engineering team switched to ion engine #2, which is mounted on a different gimbal, and conducted tests with it from July 14 to 16. They have confirmed that the spacecraft is ready to continue with the exploration of Ceres.

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More Pluto news!

10:36 am

Sputnik Planum on Pluto

At a press conference today Alan Stern led off by dubbing Pluto-Charon as a “double planet system”. Some new results:

  • Tombaugh Regio (the heart) has been identified as a region of carbon monoxide.
  • The atmosphere extends out to about 600 miles. It is comprised of hydrocarbosn, methane, and nitrogen, with nitrogen the main component. It is naturally escaping from the planet, ionized by the solar wind. The consequence is that a substantial amount of Pluto has evaporated away over time. The numbers are not yet quantified, but will be as more data arrives.
  • The images once again suggest significant activity over time, both of erosion and tectonic processes. One flat plain, dubbed Sputnik Planum, is what one scientist described as “difficult to explain terrain.” The image is to the right. Some of its features resemble icecap glaciers, which are formed by processes that do not exist on Pluto. There also appear to be wind streaks on this planum!
  • They have named a mile high mountain has been dubbed Norgay Montes after the man who accompanied Edmund Hillary to the summit of Mt. Everest.

As the scientists warned today, every conclusion right now is very speculative, and should be taken with a very big grain of salt.

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Weird geology on Charon

12:57 pm

Charon's mountain in a moat

As they await the arrival of more data from New Horizons, the science team have highlighted this interesting and entirely puzzling feature revealed in their first global image from Charon, shown in the image on the right, a mountain inside a depression. Note also the nearby rill-like depressions running from one crater to the next.

My first thought is that the mountain, which in this relatively low resolution image looks almost like a really gigantic boulder, is made of material denser than the ground in which it sits, and some heating event caused the ground to soften and collapse, dropping the mountain-sized boulder down into the sinkhole.

I am guessing of course. What we have here is a very alien environment, with geological processes in temperatures and densities and gravities to which we are wholly unfamiliar. What we would normally expect to happen is not something we should expect to normally happen on either Charon or Pluto.

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Growing and eating lettuce on ISS

8:59 am

Astronauts are about to eat a crop of romaine lettuce that they have grown entirely from seed on ISS.

The story is important as it indicates that the engineering to grow plants in space is continuing to improve. The article however is very wrong when it says that this will be the first salad grown and eaten in space. Russian astronauts have been working on this problem on their space stations since the 1970s, and in at least one case — which was captured on video almost a decade ago — have eaten space-grown lettuce. (I wrote about this event for Air & Space back in 2003.)

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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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First New Horizons fly-by images released

12:31 pm

Ice mountains on Pluto

Many cool images! I will only post one, on the right, of the ice mountains seen at the southernmost edge of Tombauh Regio. More can be seen here.

Some quick facts revealed during today’s the press conference:

  • They have gotten good data on Pluto’s atmosphere. Earlier data just before fly-by suggested that there are specific regions on the surface that have a lot of methane, but with different properties depending on location.
  • They have found that the surface of Charon is active. It also looks like a weird Moon, cratered, with a dark mare region they have dubbed Mordor. Its cause however is not the same as the Moon. There are also a large sequence of troughs and cliffs that are unlike other planets. Some areas are very smooth, as they they have been repaved after cratering. And there is a canyon that is very very deep, 3 miles deep, that makes it relatively deeper than any other canyon in the solar system.
  • Pluto’s moon Hydra is not spherical, and in fact looks like an asteroid.
  • The white heart is now been named Tombaugh Regio after one of Pluto’s discoverers. In its southern extent there are mountains and strange pits. And this area has no impact craters, meaning this is a very young surface, less than 100 million years old. The mountains have to made of ice, which is essentially the only thing that can be bedrock at Pluto’s temperatures, based on what they think Pluto is composed of.
  • The data shows repeatedly that a tiny planet can still have geological activity after billions of years, even without a giant gas giant nearby to produce tidal heating.
  • They have named the giant whale-shaped dark region at the equator Cthulu Regio.

The data and images will be coming back from New Horizons for the next year, so the show is certainly not over.

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“We are in lock with telemetry with the spacecraft!”

5:56 pm

The quote above was a confirmation from mission control that New Horizons survived the fly-by and is functioning perfectly.

They are still confirming if everything is A-Okay, but so far everything appears to exactly that. People are very jubilant at mission control.

They got the signal early, at the very beginning of their window.

They have now confirmed that they have a healthy spacecraft, and that “They are outbound from Pluto.”

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Pluto and Charon in false color

5:03 pm

Pluto and Charon in false color

While waiting for word about how New Horizons has fared during its close fly-by of Pluto, the science team today released the false color images on the right of both Pluto and Charon to illustrate the complicated surface geology of both planetary bodies.

The new color images reveal that the “heart” of Pluto actually consists of two remarkably different-colored regions. In the false-color image, the heart consists of a western lobe shaped like an ice cream cone that appears peach color in this image. A mottled area on the right (east) side looks bluish. A mid-latitude band appears in shades ranging from pale blue through red. Even within the northern polar cap, in the upper part of the image, various shades of yellow-orange indicate subtle compositional differences. This image was obtained using three of the color filters of the Ralph instrument on July 13 at 3:38 am EDT and received on the ground on at 12:25 pm.

The surface of Charon is viewed using the same exaggerated color. The red on the dark northern polar cap of Charon is attributed to hydrocarbon and other molecules, a class of chemical compounds called tholins. The mottled colors at lower latitudes point to the diversity of terrains on Charon. This image was obtained using three of the color filters of the Ralph instrument on July 13 at 3:38 am EDT and received on the ground on at 12:25 pm.

Word on the spacecraft’s status will arrive at around 9 pm (eastern) tonight. Images and data will then follow, assuming all is well.

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Some speculations from scientists about Pluto data

10:28 am

Using the images and data so far received from New Horizons, planetary scientists outline some of their tentative conclusions as well as speculate about what it means.

[Alan Stern, New Horizons’ principal investigator] says Pluto’s surface appears to be much less heavily cratered than its large moon, Charon—which implies that the surface has been paved over in some way. That smoothing process could come from internal heat that keeps rock and ice soft, or by the frosts that snow down and blanket the surface in fresh ice. “Either [Pluto’s] internal engine continues to run, and there are active processes that are taking place,” Stern says, “or those atmospheric processes are themselves covering up the geology, and covering up the craters.”

Jonathan Lunine, a planetary scientist at Cornell University, not on the New Horizons team, favors the latter explanation. His initial impression is that Pluto is far more cratered than Triton, the moon of Neptune that is about the same size as Pluto and is thought to be a captured Kuiper belt object. Triton has a famous “cantaloupe” terrain, thought to have formed as heat, driven by Saturn’s tidal pull, allowed molten blobs of ice to rise and overturn. Parts of Pluto’s rugged surface seem to be far more carved and cratered, Lunine says. “It’s telling me that [Pluto’s] crust was not heated and modified to the extent that it was on Triton.”

Above all, however, I like Lunine’s comment at the end of the article:

Lunine says the emerging diversity on Pluto—of both active atmospheric and geological processes—makes him disagree with the decision of International Astronomical Union to call Pluto a dwarf. “This really is a planet,” he says. He notes that electrons have a double definition as a particle and a wave. “Why can’t we call Pluto a planet and a Kuiper belt object?” he asks. “I think we have to think of it as both.”

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Pluto just before close encounter

9:39 am

Pluto just before close encounter

Today’s cool image, on the right, is the last one New Horizons sent back to Earth before its July 14th close encounter. Be sure you click here to see the full resolution version. It is quite spectacular. It was taken from about 476,000 miles, about twice the distance to the Moon.

The quality of this image strongly suggests that all will go well with the encounter today. However,

Per the plan, the spacecraft currently is in data-gathering mode and not in contact with flight controllers at the Johns Hopkins University Applied Physical Laboratory (APL) in Laurel, Maryland. Scientists are waiting to find out whether New Horizons “phones home,” transmitting to Earth a series of status updates that indicate the spacecraft survived the flyby and is in good health. The “call” is expected shortly after 9 p.m. tonight.

So, at 9 pm (Eastern) we will hear from New Horizons on its status. Images and data from the encounter itself however will arrive over time, beginning tonight and continuing throughout the coming months.

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The size of Pluto pinned down

12:59 pm

Data from New Horizons has allowed scientists to more firmly determine, for the first time, Pluto’s precise size.

Mission scientists have found Pluto to be 1,473 miles (2,370 kilometers) in diameter, somewhat larger than many prior estimates. Images acquired with the Long Range Reconnaissance Imager (LORRI) were used to make this determination. This result confirms what was already suspected: Pluto is larger than all other known solar system objects beyond the orbit of Neptune. “The size of Pluto has been debated since its discovery in 1930. We are excited to finally lay this question to rest,” said mission scientist Bill McKinnon, Washington University, St. Louis.

Pluto’s newly estimated size means that its density is slightly lower than previously thought, and the fraction of ice in its interior is slightly higher. Also, the lowest layer of Pluto’s atmosphere, called the troposphere, is shallower than previously believed.

This means that Pluto is at this moment the largest Kuiper Belt object so far known, bigger than Eris, the Kuiper Belt planet discovered in 2005 that had been thought to be bigger than Pluto and whose existence was used by some to demote Pluto’s status as a planet.

I say, they are both planets, because they are both heavy enough for gravity to have forced them to become spherical.

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The approaching perihelion of Comet 67P/C-G

9:08 am

The Rosetta science team has prepared a FAQ outlining what we should expect next month as Comet 67P/C-G reaches and passes its closest point to the Sun, with Rosetta (and hopefully Philae) there to watch.

The most interesting detail they note is this:

Will the comet break apart during perihelion?

The comet has not broken apart during its many previous orbits, so it is not expected to do so this time, but it cannot be ruled out. Scientists are keen to watch the possible evolution of a 500 m-long fracture that runs along the surface of the neck on the comet during the peak activity.

You can see an image from Rosetta that shows this fracture here. As I wrote then,

The biggest fracture line appears to be a meandering line that is traveling from the image’s top center to its mid-right. There also appear to be parallel lines below it. As we are looking at the nucleus’s neck, these lines suggest that the connection between the two large lobes is somewhat strained, and that it is not unlikely that these two sections will break apart at some time in the future. Though there is no way to predict at this time when that will happen, it will be truly exciting if it happens when Rosetta is in the neighborhood.

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Pluto on July 11

8:55 am

Pluto on July 11

Another cool image for Monday morning: As the spacecraft zooms towards its Tuesday fly-by, it continues to take images of Pluto, even as the planet rotates. For example, compare today’s image on the right with the one I posted yesterday. You can see some of the same features (the donut-like, crater-like feature is the most obvious), but their positions are different because of the planet’s six-day rotation.

Note also that the row of black spots along the equator show more details. Not unexpectedly, they are not as simple as the early fuzzy images suggested. Unfortunately, we will not get to see even more details, as these features will not be in view during the fly-by.

Update: See this link for a new image of Charon.

More and more to come!

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The last image of Pluto’s opposition hemisphere

11:42 pm

Pluto's opposition hemisphere

Cool image time! The New Horizons team has released the best image they are ever going to get of the hemisphere that will be facing away from the spacecraft when it does its fly-by on July 14.

The spots appear on the side of Pluto that always faces its largest moon, Charon—the face that will be invisible to New Horizons when the spacecraft makes its close flyby the morning of July 14. New Horizons principal investigator Alan Stern of the Southwest Research Institute, Boulder, Colorado, describes this image as “the last, best look that anyone will have of Pluto’s far side for decades to come.”

The spots are connected to a dark belt that circles Pluto’s equatorial region. What continues to pique the interest of scientists is their similar size and even spacing. “It’s weird that they’re spaced so regularly,” says New Horizons program scientist Curt Niebur at NASA Headquarters in Washington. Jeff Moore of NASA’s Ames Research Center, Mountain View, California, is equally intrigued. “We can’t tell whether they’re plateaus or plains, or whether they’re brightness variations on a completely smooth surface.”

No one will likely have the answers to these questions for a long time, as it might take as long as a half century before before anyone can get another spacecraft there.

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Ceres’ white spots might be salt not water

6:16 pm

The uncertainty of science: The principal investigator of Dawn has indicated that the preliminary data they have gotten of Ceres’ white spots strongly suggests that they are not water but salt.

The mystery is far from completely solved, Russell cautioned. The team failed to get the quality of measurements they wanted in examining the spots, and they’ll have to try again at a closer orbit — like the next planned mapping orbit, which will take them from 2,700 miles over the surface to just 900. The photos taken at that height will also have significantly better resolution, which should further help the team determine what the spots are made of.

But based on the spectral data the team did get, Russell said, the spots “really don’t look like mounds of ice. … The bright spots are probably — like you might find in the desert on Earth — a salt plain where maybe water came out at one time and evaporated,” Russell said.

None of this is confirmed, and won’t be until they lower Dawn’s orbit to get higher resolution images. However, this must wait because they have extended Dawn’s mapping orbit for now as they review the issue that caused the safe mode incident on June 30.

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Another new Pluto image

6:02 pm

Pluto geology

Cool image time! The New Horizons science team released another image of Pluto on Friday, this time showing enough details that they can begin to see geological features.

New Horizons’ latest image of Pluto was taken on July 9, 2015 from 3.3 million miles (5.4 million kilometers) away, with a resolution of 17 miles (27 kilometers) per pixel. At this range, Pluto is beginning to reveal the first signs of discrete geologic features. This image views the side of Pluto that always faces its largest moon, Charon, and includes the so-called “tail” of the dark whale-shaped feature along its equator. (The immense, bright feature shaped like a heart had rotated from view when this image was captured.)

“Among the structures tentatively identified in this new image are what appear to be polygonal features; a complex band of terrain stretching east-northeast across the planet, approximately 1,000 miles long; and a complex region where bright terrains meet the dark terrains of the whale,” said New Horizons principal investigator Alan Stern.

Be sure to click on the link to see the full resolution version of the image.

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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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Juno flight plan at Jupiter revised

10:16 am

In preparation for its arrival in orbit around Jupiter in about a year, engineers for the unmanned probe Juno have revised their planned orbital maneuvers.

Following a detailed analysis by the Juno team, NASA recently approved changes to the mission’s flight plan at Jupiter. Instead of taking 11 days to orbit the planet, Juno will now complete one revolution every 14 days. The difference in orbit period will be accomplished by having Juno execute a slightly shorter engine burn than originally planned.

The revised cadence will allow Juno to build maps of the planet’s magnetic and gravity fields in a way that will provide a global look at the planet earlier in the mission than the original plan. Over successive orbits, Juno will build a virtual web around Jupiter, making its gravity and magnetic field maps as it passes over different longitudes from north to south. The original plan would have required 15 orbits to map these forces globally, with 15 more orbits filling in gaps to make the map complete. In the revised plan, Juno will get very basic mapping coverage in just eight orbits. A new level of detail will be added with each successive doubling of the number, at 16 and 32 orbits.

The change will extend the official mission from 15 to 20 months, though I expect that even this will be extended if the spacecraft’s fuel holds out.

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New radio communications from Philae

9:35 am

On July 9 Philae successfully transmitted data to Rosetta for the first time in more than two weeks.

Although the connection failed repeatedly after that, it remained completely stable for those 12 minutes. “This sign of life from Philae proves to us that at least one of the lander’s communication units remains operational and receives our commands,” said Koen Geurts, a member of the lander control team at DLR Cologne.

The mood had been mixed over the last few days; Philae had not communicated with the team in the DLR Lander Control Center (LCC) since 24 June 2015. After an initial test command to turn on the power to CONSERT on 5 July 2015, the lander did not respond. Philae’s team began to wonder if the lander had survived on Comet 67P/Churyumov-Gerasimenko.

The intermittent nature of Philae’s attempts at communication are puzzling. Normally, they either would have communications or they would not. For good communications to break off like this repeatedly is puzzling. It is almost as if there is a loose wire causing communications to go on and off, which seems an unlikely explanation for this problem.

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New image of Pluto and Charon

12:02 am

Pluto and Charon

The New Horizons science team today released a new image showing both Pluto and Charon, and not unexpectedly, they are very different from each other.

A high-contrast array of bright and dark features covers Pluto’s surface, while on Charon, only a dark polar region interrupts a generally more uniform light gray terrain. The reddish materials that color Pluto are absent on Charon. Pluto has a significant atmosphere; Charon does not. On Pluto, exotic ices like frozen nitrogen, methane, and carbon monoxide have been found, while Charon’s surface is made of frozen water and ammonia compounds. The interior of Pluto is mostly rock, while Charon contains equal measures of rock and water ice. “These two objects have been together for billions of years, in the same orbit, but they are totally different,” said Principal Investigator Alan Stern of the Southwest Research Institute (SwRI), Boulder, Colorado.

For a half century, since the first probes left Earth to visit other worlds, the one consistent axiom we have learned from every mission is that no two objects are going to be alike, and that every object out there is going to be incredibly unique. Pluto and Charon, in finishing the human race’s first inventory of the solar system, prove this axiom once again.

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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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A new double dynamo theory to explain the Sun’s solar cycle

10:45 am

A team of solar scientists have proposed a new theory that they think explains the ebb and flow of the Sun’s eleven year solar cycle, and if right can explain the periodic occurrence of grand minimums where there are essentially no sunspots for decades, such as the Maunder Minimum in the 1600s.

The theory proposes that the Sun has two different dynamos that produce different magnetic waves in its interior. Like waves that can either cancel each other out or combine for more power, these two dynamos do the same over time and thus effect the Sun’s sunspot/solar cycle.

“We found magnetic wave components appearing in pairs, originating in two different layers in the Sun’s interior. They both have a frequency of approximately 11 years, although this frequency is slightly different, and they are offset in time. Over the cycle, the waves fluctuate between the northern and southern hemispheres of the Sun. Combining both waves together and comparing to real data for the current solar cycle, we found that our predictions showed an accuracy of 97%,” said Zharkova.

Zharkova and her colleagues derived their model using a technique called ‘principal component analysis’ of the magnetic field observations from the Wilcox Solar Observatory in California. They examined three solar cycles-worth of magnetic field activity, covering the period from 1976-2008. In addition, they compared their predictions to average sunspot numbers, another strong marker of solar activity. All the predictions and observations were closely matched.

Looking ahead to the next solar cycles, the model predicts that the pair of waves become increasingly offset during Cycle 25, which peaks in 2022. During Cycle 26, which covers the decade from 2030-2040, the two waves will become exactly out of synch and this will cause a significant reduction in solar activity.

“In cycle 26, the two waves exactly mirror each other – peaking at the same time but in opposite hemispheres of the Sun. Their interaction will be disruptive, or they will nearly cancel each other. We predict that this will lead to the properties of a ‘Maunder minimum’,” said Zharkova. “Effectively, when the waves are approximately in phase, they can show strong interaction, or resonance, and we have strong solar activity. When they are out of phase, we have solar minimums. When there is full phase separation, we have the conditions last seen during the Maunder minimum, 370 years ago.”

And on this same subject, last week NOAA posted its monthly update of the solar cycle, showing the Sun’s sunspot activity in June. As I have done every month since 2010, I am posting it here, below the fold, with annotations to give it context.
» Read more

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Watch Opportunity’s full journey on Mars, in 8 minutes

9:54 am

The science team for the Mars rover Opportunity have released an 8-minute movie compiled from the rover’s hazard-avoidance cameras. Enjoy!

One comment: There is a long stretch of territory south of Albuquerque, New Mexico called Jornada de Muerto, which means “Journey of Death” in English. It gets its name from its lack of water or life. This video makes that stretch of land look like a water park, strongly highlighting the utter barrenness of the Martian surface.

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Best image yet of Pluto

9:29 am

Pluto

Very cool image time! The New Horizons science team today released [link fixed] their best image yet of Pluto, taken on July 7 immediately following the spacecraft’s recovery from safe mode.

This view is centered roughly on the area that will be seen close-up during New Horizons’ July 14 closest approach. This side of Pluto is dominated by three broad regions of varying brightness. Most prominent are an elongated dark feature at the equator, informally known as “the whale,” and a large heart-shaped bright area measuring some 1,200 miles (2,000 kilometers) across on the right. Above those features is a polar region that is intermediate in brightness.

For the first time these features look like actual surface areas on a planet, not fuzzy blobs. We are still seeing Pluto like we saw all planets prior to the space age, but at least now we know what we are looking at.

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