The Worst Part of Losing Cassini Is That It Has No Replacement

Link here. This article is an honest review of the current lack of concrete plans by anyone to send a new probe to Saturn. While there are some tentative missions in the works, nothing is certain.

[I]f looking back on Cassini’s major discoveries at Saturn, Titan, and Enceladus have left you thirsty for more, we have some bad news: That thirst is going to go unquenched for a while. Talks of Uranus and Neptune missions are tentative at best. The best hope for Saturn now comes from NASA’s New Frontiers program, which looks for excellent medium-cost missions has spawned spacecraft including Jupiter’s Juno and Pluto’s New Horizons. This round of New Frontiers missions must launch by 2024, and there are two Enceladus proposals, a Titan proposal, and a Saturn atmospheric probe under consideration. We may hear word about those proposals by the end of the year “Hang tight, we’re going through the evaluations now and we’ll be announcing at the end of the year what some of the finalists will be,” Jim Green, NASA Planetary Science Director, said at the Cassini press conference Friday morning.

This list of possible Saturn missions sounds great, but they are all competing against each other and a number of other equally (and possibly more) interesting missions to other places. And with the federal budget out of control and mired in debt, there isn’t really a lot of money to go around.

3D image of Jupiter

Another citizen scientist who goes by the moniker of mesno has uploaded a spectacular 3D anaglyph of one of Juno’s images of Jupiter.

I could post it here, but I’d have to reduce its resolution, and I don’t think this will work well. If you have red-blue anaglyph 3D glasses the image does a great job of showing the differing vertical heights of Jupiter’s many horizontal bands, especially since it exaggerates the vertical scale significantly to bring out these differences.

Mesno has done three other anaglyphs. Check them out. The image of the Great Red Spot really shows how this is a vast whirlpool boring deep into Jupiter’s atmosphere.

Cats are liquid — if they choose to be

Science marches on! A new study shows that cats can be liquid, if they choose to be.

Fardin noticed that these furry pets can adapt to the shape of the container they sit in—think of a cat in a vase—similarly to what fluids such as water do. So he used the principles of rheology, the branch of physics that deals with the deformation of matter, to calculate cats’ relaxation time, or the time it takes for them to take up the space of a vase or bathroom sink.

The conclusion? Cats can be either liquid or solid, depending on the circumstances, Fardin reported in the Rheology Bulletin in 2014…. A cat in a small box will behave like a fluid, filling up all the space, but a cat in a bathtub full of water will try to minimize its contact with it and behave very much like a solid.

Anyone who has ever owned a cat will be understand this research. It isn’t that cats can be liquid that is expected, it is that cats will do what they want. If they want to be liquid, no one is going to stop them.

Because of this ground-breaking research, the scientist has won this year’s Ig Nobel Physics Prize.

Cassini’s mission ends

Enceladus as seen by Cassini two days before mission end

After a seven year journey and thirteen years in orbit around Saturn, Cassini’s mission ended early this morning with a dive into Saturn’s atmosphere.

The image above, cropped to show here, is actually one from a short movie, showing Enceladus setting behind the horizon of Saturn. The images were taking two days ago, but provide a fitting image for the mission’s end.

Some of the best images from the dive, including Cassini’s last image, can be found here.

While most of the press will rightly wax eloquent about the magnificence of this mission, my focus remains on what will come next. We no longer have any way to observe what is happening on Saturn. We are blind. We should not be.

New theory for formation of main asteroid belt

The uncertainty of science: Using computer models, astronomers have developed a new completely different theory to explain the existence of the asteroid belt between Mars and Jupiter.

The asteroid belt (sometimes referred to as the main asteroid belt) orbits between Mars and Jupiter. It consists of asteroids and minor planets forming a disk around the sun. It also serves as a sort of dividing line between the inner rocky planets and outer gas giants. Current theory suggests that the asteroid belt was once much more heavily populated, but the gravitational pull of Jupiter flung approximately 99 percent of its former material to other parts of the solar system or beyond. Astronomers also assumed that Jupiter’s gravity prevented the material in the belt from coalescing into larger planets. In this new effort, the researchers propose a completely different explanation of the asteroid belt’s origin—suggesting that the belt started out as an empty space and was subsequently filled by material flung from the inner and outer planets.

The new theory is interesting in that it really illustrates how little we really know about the formation of our solar system. The simple fact is that either one of these theories might be the answer, even though they propose completely opposite initial conditions. We simply do not have enough information about solar system formation in general to constrain our models and determine which of these theories is right.

Until scientists have been able to study hundreds, if not thousands, of solar systems up close, these models will be nothing more than interesting exercises in computer modeling.

Hubble spots a pitch-black exoplanet

Astronomers using the Hubble Space Telescope have determined that an exoplanet is practically pitch black, reflecting almost no light.

NASA’s Hubble Space Telescope has observed a planet outside our solar system that looks as black as fresh asphalt because it eats light rather than reflecting it back into space. This light-eating prowess is due to the planet’s unique capability to trap at least 94 percent of the visible starlight falling into its atmosphere.

The oddball exoplanet, called WASP-12b, is one of a class of so-called “hot Jupiters,” gigantic, gaseous planets that orbit very close to their host star and are heated to extreme temperatures. The planet’s atmosphere is so hot that most molecules are unable to survive on the blistering day side of the planet, where the temperature is 4,600 degrees Fahrenheit. Therefore, clouds probably cannot form to reflect light back into space. Instead, incoming light penetrates deep into the planet’s atmosphere where it is absorbed by hydrogen atoms and converted to heat energy.

Because the exoplanet is tidally locked, with one side always facing its sun and the other always in nightime, the nighttime face is estimated to be about 2,000 degrees cooler, and actually shows evidence of the existence of water vapor and clouds.

First global map of the trace water on the Moon

Trace water on moon

Using data collected by an American instrument on India’s Chandrayaan-1 lunar orbiter scientists have produced the first global map showing the locations and quantities of trace water on the Moon.

The map above, reduced to post here, is the result. The green areas at high latitudes show the most evidence of water, but the amounts remain very tiny, and the evidence remains somewhat uncertain.

Regardless, this map indicates that the high latitudes of the Moon will likely be the most valuable real estate for future colonists.

Cassini on final approach to Saturn

Engineers have confirmed that Cassini is now on its final approach to Saturn, with a scheduled dive into the gas giant set for Friday, September 15.

The mission’s final calculations predict loss of contact with the Cassini spacecraft will take place on Sept. 15 at 7:55 a.m. EDT (4:55 a.m. PDT). Cassini will enter Saturn’s atmosphere approximately one minute earlier, at an altitude of about 1,190 miles (1,915 kilometers) above the planet’s estimated cloud tops (the altitude where the air pressure is 1-bar, equivalent to sea level on Earth). During its dive into the atmosphere, the spacecraft’s speed will be approximately 70,000 miles (113,000 kilometers) per hour. The final plunge will take place on the day side of Saturn, near local noon, with the spacecraft entering the atmosphere around 10 degrees north latitude.

We will get Cassini’s last images about 90 minutes after its death.

Trump administration shuts down NIH anti-gun research

The NIH has quietly shelved all funding for gun research, most of which had been instigated under the Obama administration as a propaganda tool to promote gun control.

The article from Science is remarkable — coming from a mainstream academic source — in that it provides a fair description of the perspective of the NRA and gun-owners.

Note: Reader Kirk noted my error in originally crediting this article to Nature, when it truth it was Science that published it. Post corrected. Sorry!

An oral history of the Cassini mission to Saturn

Link here. Those who have read my book on the building of the Hubble Space Telescope will recognize many of the same people and political maneuvers used to get the project off the ground and funded.

Note too that the idea of Cassini was first proposed in 1982, but it didn’t actually launch until 1997. Fifteen years. While today I think such a spacecraft could go from concept to launch much faster, this timeline gives us a guide on when the next Saturn orbiter might launch. At the earliest do not expect another mission to Saturn to launch before 2025.

Movie of Juno’s September 1 fly-by of Jupiter

Citizen scientist Gerald Eichstädt has done it again, assembling and enhancing the images taken by Juno in its September 1, 2017 fly-by of Jupiter to produce a spectacular movie, embedded below.

In his words,

This animation reconstructs the two and a half hours from 2017-09-01T20:45:00 to 2017-09-01T23:15:00 in 125-fold time-lapse with 25 frames per second, using 20 raw JunoCam images. JunoCam is Juno’s optical and near infrared Education and Public Outreach camera.

Trajectory data are retrieved from SPICE kernels via the NAIF spy.exe tool. The NAIF/SPICE environment is the way NASA provides spacecraft navigation data.

The movie shows Jupiter in a heavily enhanced way, in order to reveal detail.

Some of the raw images cover only part of the area required to render a still of the movie. In these cases, you’ll see the border of the raw image.

Each image is rendered into a short scene. The scences overlap and are blended.

Rendering the movie took about five days. Any shortcomings of the movie are a result of imperfect image processing.

Curiosity tops Vera Rubin Ridge

Curiosity's view from on top of Vera Rubin Ridge, sol 1812

The image above is a reduced resolution version of a panorama created by reader Phil Veerkamp of images downloaded today from Curiosity. If you click on the image you can see the full resolution image. It looks to more to the east than the panorama shown in my September 6 rover update, revealing more of the type of surface the rover will have to cross on its drive forward on this new geological layer called the Hematite Unit.

Curiosity has now topped Vera Rubin Ridge, but the plateau above is really not as flat as the image implies. The Hematite Unit that the rover is now traversing still climbs upward, and they will continue to gain altitude now with almost every drive.

New Horizons team looks for second flyby in Kuiper Belt

The New Horizons science team is hoping to send their probe past a second more distant Kuiper Belt object after its January 1, 2019 flyby of 2014 MU69, if they can find an object that the spacecraft can reach.

They haven’t found any candidates yet, NASA has not agreed to a mission extension anyway, and their focus now remains the 2019 flyby. Still, if they are lucky and can get another target, this would be a nice bonus for the mission.

Cassini says goodbye to Saturn

Saturn, October 2016

Cool image time! The picture above, reduced in resolution to show here, was taken in October 2016 during one of Cassini’s last distant orbits that gave it a global view of Saturn and its rings. Since it began its dives close to the gas giant such views have not been possible.

The mission ends this coming Saturday with a dive into Saturn. It was launched in October 1997, and after a seven year journey has spent the last thirteen years in orbit around the planet, providing us the first long term glimpse of a gas giant as its seasons evolved.

Cassini has been orbiting Saturn for nearly a half of a Saturnian year but that journey is nearing its end. This extended stay has permitted observations of the long-term variability of the planet, moons, rings, and magnetosphere, observations not possible from short, fly-by style missions.

When the spacecraft arrived at Saturn in 2004, the planet’s northern hemisphere, seen here at top, was in darkness, just beginning to emerge from winter (see Cassini’s Holiday Greetings​). Now at journey’s end, the entire north pole is bathed in the continuous sunlight of summer.

The spacecraft was also able to observe the seasonal changes that occurred to Titan. It also studied the plumes coming from the tiger stripe cracks on Enceladus, shown below the fold in a movie created by Cassini over a 14 hour time period in August 2017.

I expect that scientists will be exploring Cassini’s data archive for decades, finding many things not noticed in their initial viewing. Unfortunately, we will not have another spacecraft taking new pictures in orbit around Saturn to compare with Cassini’s past images for many decades to come. On Saturday, we go blind.
» Read more

Saturn’s magnificent rings

Saturn's rings

The Cassini science team released two sets of images taken by the spacecraft of Saturn’s rings.

The image above, reduced in resolution to show here, is from the second link. As they note,

The pale tan color is generally not perceptible with the naked eye in telescope views, especially given that Saturn has a similar hue.

The material responsible for bestowing this color on the rings—which are mostly water ice and would otherwise appear white—is a matter of intense debate among ring scientists that will hopefully be settled by new in-situ observations before the end of Cassini’s mission.

The different ringlets seen here are part of what is called the “irregular structure” of the B ring. Cassini radio occultations of the rings have shown that these features have extremely sharp boundaries on even smaller scales (radially, or along the direction outward from Saturn) than the camera can resolve here. Closer to Saturn, the irregular structures become fuzzier and more rounded, less opaque, and their color contrast diminishes.

Check out both. They reveal to me that our understanding of these rings remains essentially nil, even after more than a dozen years of study by Cassini.

First Juno movie of Jupiter’s changing weather

Gerald Eichstädt at the Juno image site has produced the first attempt to assemble a movie of Juno images of the same area on Jupiter in order to show its changing weather.

JunoCam has been seeing this scene about six times from very different perspectives between about 2017-09-01T22:03 and about 2017-09-01T22:19, hence a over a little more than 15 minutes.

This animation is a first attempt to reproject the six images to a similar common perspective in order to reveal some dynamical information.

An movie covering only 15 minutes won’t show much change, but it is a start. He also notes that in making the different images match up he likely introduced some artifacts that are not real.

Plan of New Horizons’ fly-by of 2014 MU69 announced

The New Horizons science team has announced its detailed plan for the January 1, 2019 fly-by of Kuiper Belt object 2014 MU69.

If all goes as planned, New Horizons will come to within just 2,175 miles (3,500 kilometers) of MU69 at closest approach, peering down on it from celestial north. The alternate plan, to be employed in certain contingency situations such as the discovery of debris near MU69, would take New Horizons within 6,000 miles (10,000 kilometers) — still closer than the 7,800-mile (12,500-kilometer) flyby distance to Pluto.

…If the closer approach is executed, the highest-resolution camera on New Horizons, the telescopic Long Range Reconnaissance Imager (LORRI) should be able to spot details as small as 230 feet (70 meters) across, for example, compared to nearly 600 feet (183 meters) on Pluto.

MU69 is thought to either be two objects orbiting very close to each other or an object similar to Comet 67P/C-G, two objects in contact but barely so.

In a related New Horizons story, the International Astronautical Union (IAU) has officially accepted 14 names chosen by the New Horizons team for features on Pluto.

Juno finds mystery in Jupiter’s aurora

The uncertainty of science: Scientists analyzing the data sent back by Juno have found that the system for generating Jupiter’s aurora does not appear to be same as the process that creates auroras on Earth.

The science here is a bit complicated. Suffice it to say that Jupiter’s aurora seems produced by a much more complex process, which actually should not have surprised anyone, considering how much larger Jupiter is and more powerful its magnetic field.

Mars rover update: September 6, 2017

Summary: Curiosity ascends up steepest part of Vera Rubin Ridge, getting just below the ridgetop, while Opportunity inspects its footprint in Perseverance Valley.

Curiosity

For the overall context of Curiosity’s travels, see Pinpointing Curiosity’s location in Gale Crater.

Curiosity panorama, Sol 1807

Curiosity's location, Sol 1802

Since my last update on August 11, Curiosity has been slowly working its way along the base of Vera Rubin Ridge, and up its slope. Today’s update from the science team describes how the rover is now on the steepest part of that slope, which is also just below the ridgetop. The panorama above looks east at the ridge, at the sand-duned foothills in the Murray Formation that Curiosity has been traversing since March 2016, and the crater plains beyond.

The image on the right shows Curiosity’s approximate position, with the point of view of the panorama indicated. The image also shows their planned upcoming route across the Hematite Unit. As they note in their update:

Curiosity now has great, unobstructed views across the lowlands of Gale crater to the rear of the rover. The view is improving as the air becomes clearer heading into the colder seasons. The first image link below shows a Navcam view into the distance past a cliff face just to the left of the rover. The image is tilted due to the to the unusually high 15.5 degree tilt of the rover as it climbs the ridge. Part of Mount Sharp is in the background. The second link shows an image looking ahead, where we see much more rock and less soil. The foreground shows that some of the pebbles are relatively well rounded. The rock face up ahead is smooth, which will mean easier driving.

That report I think is somewhat optimistic.
» Read more

Sunspot update for August 2017

Yesterday NOAA posted its monthly update of the solar cycle, covering sunspot activity for August. That graph is posted below, with annotations.

August 2017 Solar Cycle graph

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.

The long slow decline to solar minimum has now shown itself. Up until now, the ramp down from solar maximum had been fast and steep, unlike past solar cycles where the ramp down is slow and steady. The last few months the ramp down had practically ceased. In this August graph the ramp down turned into a temporary ramp up. Considering the strong activity going on right now as well as the past week, I expect the September numbers to also show this increase.

None of this means that the ramp down has ended, or that we will not see a solar minimum. All it means is that it takes awhile for the Sun to slowly calm down after each solar maximum. The sunspots we are seeing right now, all near the equator, are from the solar cycle now slowly ending. We will know the minimum is coming as well as the next solar maximum when the first tiny and rare sunspots appear in high latitudes. These high latitude sunspots will belong to the next cycle, and will have reversed polarity.

First images released from Juno’s seventh close fly-by of Jupiter

Jupiter's South pole, August 2017

Cool image time! The raw images taken during Juno’s seventh close fly-by of Jupiter have been released. The image on the right, reduced in resolution to post here, was reprocessed by Gerald Eichstädt and shows the gas giant’s south polar region.

It is worthwhile comparing this with previous south pole images, as well as other images from this fly-by reprocessed by Eichstadt. I want to know whether anyone can identify specific storms and show how they have changed over time. Unfortunately, Juno’s orbit is large, and so it only drops in close every 53 days, allowing for these storms to change a great deal, and thus making it more difficult to link images of the same changing storm. Moreover, the images don’t necessarily show the same longitudes on Jupiter, making this even more difficult.

Nonetheless, to gain a real understanding of Jupiter’s atmosphere will require a clear understanding of the pace in which its storms and atmosphere change. These images might give us our first glimpse of this process.

Senate/House budget conflicts over science and space

Link here. The article gives a good overview, from a pro-science, pro-big spending perspective, of some of the significant budget differences between the proposed House and Senate budgets for 2018.

Except for NASA’s planetary program, the House generally wants to cut more than the Senate. This once again reflects the overall political trends. Because House membership changes more frequently (its members must face the voters every two years), the positions of its membership tend to reflect more closely the wishes of the voters. The Senate meanwhile (with only one-third of its membership facing re-election every two years and with six year terms for all senators) has historically trailed behind, defending past positions that are no longer popular with the voters.

If you want to predict the political future, look at what the House proposes. The budget proposals here reflect the increasing desire of the voters to trim back the federal government. Congress (and the establishment Republican leadership) might not yet realize this, but the trends show it. Soon (I hope after 2018), the resistance by that leadership and within the Senate will break, and we shall finally see some major budget cutting.

New study claims global warming caused 2015 spike in road deaths

This is why global warming activists have little credibility: A new study has concluded that global warming, not increased use of cell phones, caused the increased number of road deaths in 2015.

Combining government data for the 100 most densely-populated U.S. counties for miles driven, vehicle fatalities and weather, researcher Leon Robertson found that motorists clock up extra miles as temperatures and precipitation rates rose. When temperature rose by a degree Fahrenheit (0.5 Celsius), vehicles were driven an additional 60 miles (95 kms) per person over a year, Robertson said in the study, which was published in the academic journal Injury Prevention.

Using mathematical models, the retired Yale University epidemiologist also found that for every additional inch (2.5 cm) of rainfall, cars and trucks racked up an average of 66 more miles (105 kms) per motorist for a year. Hotter than normal outdoors temperatures likely accounted for most of the extra deaths in 2015, Robertson said.”If millions more people drive cars because the temperature is getting warmer … then that adds up to a lot of miles,” he told the Thomson Reuters Foundation.

“Mainly it’s a simple multiplication.”

Since road deaths apparently dropped in 2016, does this mean that global warming has ceased?

Mars or a bacterial cell?

Mars's southern polar regions

Cool image time! The image on the right, reduced and cropped to show here, was taken by Mars Reconnaissance Orbiter and shows just one spot in Mars’s southern polar regions. The surface only looks like bacteria because the basic structure of both is based on fractals. Scientists call this area “swiss-cheese terrain” because of the many holes that have opened up there.

The texture is very alien, bearing more of a resemblance to the universe of the very small, rather than the universe far, far away. But if this is a polar cap, then why does it not look like the polar caps on Earth? Indeed, there is no equivalent terrain observed here on Earth.

The so-called “Swiss cheese terrain,” referencing the numerous holes of the region, is a product of seasonal exchange between the surface and the Martian atmosphere. With a predominantly carbon dioxide content at 98 percent, the colder temperatures condense the gas out of the atmosphere to produce dry ice. The prevalence of water is more concentrated in the north, leaving the South polar region more carbon dioxide rich, and it’s this difference in composition that generates the unusual texture of the Swiss cheese terrain.

Be sure and take a look at the full resolution image. It is quite wild.

Cassini movie flying past Saturn’s rings

movie of Cassini flying past Saturn's rings

Cool image time! The Cassini science team has assembled a short movie from 21 images taken by the spacecraft during its August 20th dive between the rings and Saturn. That animation is to the right.

Only two weeks remain in the Cassini mission. The spacecraft dives into Saturn on September 15.

The spacecraft is expected to lose radio contact with Earth within about one to two minutes after beginning its descent into Saturn’s upper atmosphere. But on the way down, before contact is lost, eight of Cassini’s 12 science instruments will be operating. In particular, the spacecraft‘s ion and neutral mass spectrometer (INMS), which will be directly sampling the atmosphere’s composition, potentially returning insights into the giant planet’s formation and evolution. On the day before the plunge, other Cassini instruments will make detailed, high-resolution observations of Saturn’s auroras, temperature, and the vortices at the planet’s poles. Cassini’s imaging camera will be off during this final descent, having taken a last look at the Saturn system the previous day (Sept. 14).

The second link above gives a detailed moment-by-moment breakdown of the final six days.

I would have posted this earlier this week, but my limited internet access made it impossible. Sorry about that.

Astronomers search for water on Trappist-1 ecoplanets

The uncertainty of science: New research suggests that the Earth-sized exoplanets circling Trappist-1 might have water, or might not.

The data suggests the inner planets likely have lost all their water, but the outer planets, some of which are in the habitable zone, could have water. The key word is “could.” They actually don’t yet have any data that says for sure whether water is there..

Posted as we drive through Kayenta in the Navaho Reservation.

Akatsuki finds super-rotating equatorial jet on Venus

Japan’s Venus orbiter Akatsuki has discovered a previously unseen equatorial jet with wind speeds that often exceed 200 miles per hour.

The winds, named “equatorial jet” by the research team, were found from July to August 2016 when an infrared camera captured images of areas about 45 to 60 kilometers above the planet’s surface. The areas are invisible at optical wavelengths due to extremely dense clouds of sulfuric acid. The camera spotted thick clouds traveling at a speed of 288 kph to 324 kph near the planet’s equator.

Based on the news reports, it appears the significance of this discovery is that they identified a particular jet stream at a specific latitude. Previous observations did not have that resolution.

This would have been posted in the morning, but the internet access here in this Torrey hotel is almost as slow as what I experienced in Glacier. I had it written, but I sinply couldn’t get it to post this morning.

Global warming and Glacier National Park

One of the main activities for almost everyone visiting Glacier National Park is to drive across the park on Going-to-the-Sun Road, which crosses the mountains and probably has some of the most spectacular scenery of any road in the United States. During our visit this week we entered the park from the west side, spent several days there hiking trails, then took this road across to the east side, where we did more hiking.

The highest point on Going-to-the-Sun Road is Logan Pass. The park service has built a visitor center there, where everyone stops to do a short hike and admire the views. The trail head for the more challenging Highline Trail, which we did soon after arrival, is also here.

Outside the Logan Pass visitor center are a variety of displays. One focused on the changing environment at Glacier, and not surprisingly, it made a point of talking about the documented shrinkage of the glaciers during the past century. Below is an image of the pertinent quote from that display:

Display outside Logan Pass visiter center

When I saw this I was quite amused. The glaciers in the park are expected to be gone in only three more years, by 2020? Not a chance. I thought, they are going to have to change this sign soon. In fact, based on my experience with past failed global warming predictions, I was actually surprised they had let this display stay there this long, and hadn’t already made it vanish to be replaced with a new doomsday prediction that was far enough in the future that they could use if for awhile to generate new fear (and funding) before it too turned out to be wrong.

Anyway, in driving east and down from Logan Point, Diane and I eventually reached the east entrance to the park, where there was another visitor center. Like Logan Pass, this center also had a collection of outdoor displays, with one display once again focused on the park’s changing environment. Below is the pertinent quote from that display:
» Read more

Astronomers produce best image yet of a star

The uncertainty of science: Astronomers have produced the best image so far of the surface face of a star.

The star is Antares, and it provides some details of the star’s complex outer layers. If I was home and had good internet access, I’d post it here.

At the same time, it should be noted that this is not a real image. It is recreated from four telescopes, using interferometry to combine the images, and also includes it a great deal of assumptions and uncertainties in its creation.

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