Tag Archives: science

The dance of two Neptunian moons

Scientists have discovered that the orbital interplay between two of Neptune’s moon keep them close together but never touching. Instead, they dance about each other.

In this perpetual choreography, Naiad swirls around the ice giant every seven hours, while Thalassa, on the outside track, takes seven and a half hours. An observer sitting on Thalassa would see Naiad in an orbit that varies wildly in a zigzag pattern, passing by twice from above and then twice from below. This up, up, down, down pattern repeats every time Naiad gains four laps on Thalassa.

Although the dance may appear odd, it keeps the orbits stable, researchers said.

I have embedded below the fold a video that illustrates this.

» Read more

Share

A journey into the depths of Valles Marineris

Valles Marineris

Cool image time! Rather than start with the cool image, let’s begin with the long view. To the right is a wide mosaic of Valles Marineris on Mars, the largest known canyon in the solar system. About 2,500 miles long and 400 miles wide, this canyon is so large that it would cover most of the United States if put on Earth. The Grand Canyon, 500 miles long by 19 miles wide, could easily fit within it and not be noticed. In depth Valles Marineris is equally impressive, with a depth of more than four miles, about four times deeper than the Grand Canyon.

A closer view of the central regions of Valles Marineris

The white cross in the mosaic above is where we are heading. You can see it as the white box in the zoomed in overview to the right. This central part of Valles Marineris is named East Melas Chasma, and the red boxes indicate locations where the high resolution camera of Mars Reconnaissance Orbiter (MRO) has already taken images.

As you can see, we do not yet have many high resolution images of this part of the canyon floor. The white box is the most recent image, and is the subject of today’s post.
» Read more

Share

Upcoming big satellite constellations vex and worry astronomers

Astronomers are expressing increasing distress over the possible negative consequences to their Earth-based telescope observations from the several new giant satellite constellations being launched by SpaceX and others.

[M]any astronomers worry that such ‘megaconstellations’ — which are also planned by other companies that could launch tens of thousands of satellites in the coming years — might interfere with crucial observations of the Universe. They fear that megaconstellations could disrupt radio frequencies used for astronomical observation, create bright streaks in the night sky and increase congestion in orbit, raising the risk of collisions.

The Nature article then details the issues faced by some specific telescopes. Hidden within the article however was this interesting tidbit that admitted the problem for many telescopes is really not significant.

Within the next year or so, SpaceX plans to launch an initial set of 1,584 Starlink satellites into 550-kilometre-high orbits. At a site like Cerro Tololo, Chile, which hosts several major telescopes, six to nine of these satellites would be visible for about an hour before dark and after dawn each night, Seitzer has calculated.

Most telescopes can deal with that, says Olivier Hainaut, an astronomer at the European Southern Observatory (ESO) in Garching, Germany. Even if more companies launch megaconstellations, many astronomers might still be okay, he says. Hainaut has calculated that if 27,000 new satellites are launched, then ESO’s telescopes in Chile would lose about 0.8% of their long-exposure observing time near dusk and dawn. “Normally, we don’t do long exposures during twilight,” he says. “We are pretty sure it won’t be a problem for us.” [emphasis mine]

The article then proceeds with its Chicken-Little spin as if the astronomical world is about to end if something is not done to stop or more tightly control these new satellite constellations.

As indicated by the quote above, it appears however that the threat is overstated. The constellations might reduce observing time slightly on LSST, scheduled for completion in 2022 and designed to take full sky images once every three nights. Also, the satellite radio signals might impact some radio astronomy. In both cases, however, the fears seem exaggerated. Radio frequencies are well regulated, and LSST’s data should easily be able to separate out the satellite tracks from the real astronomical data.

Rather than demand some limits or controls on this new satellite technology, the astronomical community should rise to the occasion and find ways to overcome this new challenge. The most obvious solution is to shift the construction of new telescopes from ground-based to space-based. In fact, this same new satellite technology should make it possible for them to do so, at much less cost and relatively quickly.

But then, astronomers are part of our modern academic community, whose culture is routinely leftist and therefore fascist in philosophy (even though they usually don’t realize it). To them too often the knee-jerk response to any competition is to try to control and squelch it.

We shall see if the astronomers succeed in this case.

Share

Both methane and oxygen fluctuate in unison seasonally in Gale Crater

The uncertainty of science: According to a new science paper, data from Curiosity on Mars has now found that both methane and oxygen fluctuate in unison seasonally in Gale Crater.

From the paper’s abstract:

[T]he annual average composition in Gale Crater was measured as 95.1% carbon dioxide, 2.59% nitrogen, 1.94% argon, 0.161% oxygen, and 0.058% carbon monoxide. However, the abundances of some of these gases were observed to vary up to 40% throughout the year due to the seasonal cycle. Nitrogen and argon follow the pressure changes, but with a delay, indicating that transport of the atmosphere from pole to pole occurs on faster timescales than mixing of the components. Oxygen has been observed to show significant seasonal and year‐to‐year variability, suggesting an unknown atmospheric or surface process at work. These data can be used to better understand how the surface and atmosphere interact as we search for signs of habitability.

The data shows that the unexpected and so far unexplained seasonal oxygen fluctuation appears to track the same seasonal methane fluctuations. While biology could cause this signature, so could geological processes, though neither can produce these fluctuations easily.

Meanwhile, adding to the uncertainty were results from the two European orbiters, Mars Express and Trace Gas Orbiter. Both have failed to detect a June 19, 2019 dramatic spike in methane that had been measured by Curiosity.

Share

China unveils Mars lander during landing simulation test

The new colonial movement: China today unveiled to the international press its first prototype Mars lander, showing it attempting a simulated controlled descent on a gigantic test stand.

The demonstration of hovering, obstacle avoidance and deceleration capabilities was conducted at a site outside Beijing simulating conditions on the Red Planet, where the pull of gravity is about one-third that of Earth.

China plans to launch a lander and rover to Mars next year to explore parts of the planet in detail.

This is the first time I have heard anything about China sending a lander/rover to Mars in 2020. Previously the reports had discussed only sending an orbiter.

I have embedded video of the test below the fold. It shows the prototype hanging by many wires from the test stand, then dropping quickly, with its engine firing, before stopping suddenly, followed by an engine burst. While impressive, it did not strike me that China is even close to sending this spacecraft to Mars. The test only proved the spacecraft’s ability to do some maneuvering during descent. It did not show that it could land.

That the project’s designer said that landing would take “about seven minutes” also suggests that they are copying the techniques used by JPL to land Curiosity. Considering that JPL’s computers have been repeatedly hacked, including some hacks identified as coming from China, it would not surprise me if China has simply stolen those techniques.

I still expect them to launch an orbiter to Mars in 2020. Whether they also send a lander and rover remains to be seen.
» Read more

Share

Hayabusa-2 begins journey back to Earth

The Hayabusa-2 science team has fired up the spacecraft’s ion engine to leave the asteroid Ryugu and began its begins journey back to Earth.

It will take about six days to exit the gravitational sphere of influence of Ryugu. During that time period they will be continually releasing real time images of the asteroid from the spacecraft’s navigation camera, as it slowly gets farther away.

In mid-December they will fire the spacecraft’s main engines for an arrival near Earth in late 2020. At that point the small return capsule holding the samples from Ryugu will separate and land in the Australian desert. Hayabusa-2, still operational, might then be given a new subsequent mission.

Share

Parker releases first data to public

The solar wind as seen from Parker
Click for full image.

Having completed its first three orbits of the Sun, the Parker Solar Probe science team today made all the data obtained available to the public.

The image to the right was taken during the first close solar flyby in November 2018. It shows solar wind particles streaming past the spacecraft.

Do not expect many spectacular images from Parker. It has a camera, but the mission’s focus is the study of the Sun’s atmosphere and solar wind, neither of which are likely to be very photogenic.

Share

Polygons on Mars

Scallops and polygons on Mars
Click for full image.

Cool image time! The photograph on the right, cropped to post here, was taken on September 25, 2019 by the high resolution camera on Mars Reconnaissance Orbiter (MRO) and made public in its November image release. It shows the weird but very typical scalloped terrain, with its adjacent polygon pattern of fractures, found routinely in the northern lowland plains of Utopia Planitia on Mars. From an earlier captioned image from 2006 of these same features:

The scalloped depressions are typical features; a smooth layered terrain located between 40 and 60 degrees in both hemispheres. Scalloped depressions probably form by removal of ice-rich subsurface material by sublimation (ice transforming directly from a solid to a gaseous state), a process that may still be active today. Isolated scalloped depressions generally have a steep pole-facing scarp and a gentler equator-facing slope. This asymmetry is interpreted as being the result of difference in solar heating. Scalloped depressions may coalesce, leading to the formation of large areas of pitted terrain.

The polygonal pattern of fractures resembles permafrost polygons that form in terrestrial polar and high alpine regions by seasonal-to-annual contraction of the permafrost (permanently frozen ground). On Earth, such polygons indicate the presence of ground ice.

On Earth these polygons are most often seen in mud, usually suggesting a drying process where the ground contracts with the lose of fluid. On Mars the cracks probably also form from contraction, but not by the lose of fluid but the lose of water ice as it sublimates into a gas.

These polygons and scallops illustrate an important feature of Mars’ vast northern plains. On large scales these plains appear flat and featureless. Up close however many many strange features, like the polygons and scallops in this image, come into view.
» Read more

Share

New Horizons team renames “Ultima Thule” to “Arrokoth”

The New Horizons team has renamed the Kuiper Belt object that the spacecraft flew past on January 1, 2019 from its informal nickname of “Ultima Thule” to “Arrokoth,” which means “sky” in Powhatan/Algonquian language.

This official, and very politically correct, name has apparently gotten the stamp of approval from the IAU.

In accordance with IAU naming conventions, the discovery team earned the privilege of selecting a permanent name for the celestial body. The team used this convention to associate the culture of the native peoples who lived in the region where the object was discovered; in this case, both the Hubble Space Telescope (at the Space Telescope Science Institute) and the New Horizons mission (at the Johns Hopkins Applied Physics Laboratory) are operated out of Maryland — a tie to the significance of the Chesapeake Bay region to the Powhatan people.

“We graciously accept this gift from the Powhatan people,” said Lori Glaze, director of NASA’s Planetary Science Division. “Bestowing the name Arrokoth signifies the strength and endurance of the indigenous Algonquian people of the Chesapeake region. Their heritage continues to be a guiding light for all who search for meaning and understanding of the origins of the universe and the celestial connection of humanity.” [emphasis mine]

It is a good name, especially because its pronunciation is straight-forward, unlike the nickname.

The blather from Glaze above, however, is quite disingenuous. The Algonquian people have had literally nothing to do with the modern scientific quest for “meaning and understanding of the origins of the unverse.” They were a stone-age culture, with no written language. It was western civilization that has made their present lives far better. And it was the heritage of western civilization, not “the indigenous Algonquian people” that made the New Horizons’ journey possible. Without the demand for knowledge and truth, as demanded by western civilization, we would still not know that Arrokoth even existed.

Share

Astronomers discover star fleeing Milky Way at 3.7 million mph

Astronomers have discovered a star that rocketing out of the Milky Way at 3.7 million miles per hour because five million years ago it made a close approach to Sagittarius A* (prounounced “A-star”), the super-massive black at the center of the galaxy.

“The velocity of the discovered star is so high that it will inevitably leave the Galaxy and never return”, said Douglas Boubert from the University of Oxford, a co-author on the study.

Astronomers have wondered about high velocity stars since their discovery only two decades ago. S5-HVS1 is unprecedented due to its high speed and close passage to the Earth, “only” 29 thousand light years away. With this information, astronomers could track its journey back into the centre of the Milky Way, where a 4 million solar mass black hole, known as Sagittarius A*, lurks.

Almost certainly there are many such stars. They are just hard to spot.

Share

Hayabusa-2 to begin return voyage on November 13

In a press conference today the science team for the asteroid probe Hayabusa-2 announced that the spacecraft will begin the first stage of its journey back to Earth tomorrow, using its ion engine to slowly pull away from Ryugu.

That first stage will take a little less than a week. Once the spacecraft gets about 25 miles from Ryugu it will leave its sphere of gravitational influence, when it will then begin its cruise phase back to Earth.

Share

Mars’ seasonally vanishing carbon dioxide polar cap

Buzzell dunes, March 19, 2019
Click for full image.

Since the onset of the Martian spring in the northern hemisphere back in March of this year, scientists have been busy using the high resolution camera on Mars Reconnaissance Orbiter (MRO) to monitor the expected sublimation and disappearance of the cap of dry ice that falls as snow to become a winter layer mantling both the more permanent icecap of water 7,000 feet deep as well as the giant dune sand seas that surround that northern icecap.

The image on the right was first posted here on Behind the Black on June 6, 2019 as part of a long article describing that northern polar icecap and its annual evolution. It shows a set of dunes that Candice Hansen of the Planetary Science Institute in Arizona, who requested the image, has dubbed “Buzzell.” When that picture was taken in March, the frozen dry ice layer of translucent carbon dioxide still coated the dunes. The image’s darkness is because the Sun has just begun to rise above the horizon at this very high latitude location (84 degrees). The circular feature is likely a buried ancient crater, with the streaks indicating the prevailing wind direction blowing both sand and frost about.

On August 9, 2019 I provided an update on this monitoring, when new images of this same location were downloaded from MRO in April and June. MRO has now taken a new image of Buzzell, on October 2, 2019. Below the fold are all these images so that you can see the sublimation and disappearance of that dry ice layer over time.
» Read more

Share

We are not going to die from climate change

Tony Heller today published this quite thorough review of the failed climate predictions by global warming scientists/activists, while also providing a great summary of the real state of our climate.

You can disagree or question him on one point or another, but the overall data once again illustrates the uncertainty that surrounds climate science. We really do not know what is going on, and any predictions that claim we do are hogwash.

Above all, take a look at the section on the benefits of increased CO2 in the atmosphere. This data is widespread and robust, and has been confirmed by agriculturists for decades. The planet is getting greener and as a result more fertile as there has been an increase in atmospheric CO2.

Meanwhile, the fear-mongers insist the world will end in just over eleven years, based not on any real data but on their emotional desire for catastrophe.

Share

Bennu & Ryugu: Two very old and strange asteroids

Bennu as seen by OSIRIS-REx
Bennu’s equatorial ridge. Click for full image.

This week the science team operating the OSIRIS-REx spacecraft at the asteroid Bennu hosted a joint conference in Tucson, Arizona, with the scientists operating the Hayabusa-2 spacecraft at the asteroid Ryugu. Both gave up-to-date reports on the science so far obtained, as well as outlined upcoming events. I was fortunate enough to attend.

First an overview. Both Bennu and Ryugu are near earth asteroids, with Bennu having an orbit that might even have it hit the Earth in the last quarter of 2100s. Both are very dark, and are rubble piles. Both were thought to be of the carbonaceous chondrite family of asteroids, sometimes referred to as C-type asteroids. This family, making up about 75% of all asteroids, includes a bewildering collection of subtypes (B-types, F-types, G-types, CI, CM, CV, CH, CB, etc), all of which were initially thought to hold a lot of carbon. We now know that only a few of these categories, the CI and CM for example, are carbon rich.

Even so, we actually know very little about these types of asteroids. They are very fragile, so that any that reach the Earth’s surface are not a good selection of what exists. About 90% of the material gets destroyed in the atmosphere, with the remnant generally coming from the innermost core or more robust nodules. We therefore have a biased and limited sample.

It is therefore not surprising that the scientists are finding that neither Bennu nor Ryugu resembles anything else they have ever seen. Both have aspects that resemble certain types of carbonaceous chondrite asteroids, but neither provides a very good fit for anything.
» Read more

Share

Watch the Mercury transit of the Sun from home!

The November 11 transit of Mercury across the face the Sun will be live streamed by the Griffith Observatory in Los Angeles.

It appears that in Los Angeles the transit will have already started at sunrise, with Mercury at that point about a third of its way across the Sun’s face. Regardless, from about 7 am to 10 am (Pacific) the observatory will provide a view.

UPDATE: Images from an event in New Zealand will upload real time telescope images of the transit here.

Share

New InSight image of mole shows collapse of hole

View of InSight drill hole
Click for full movie.

The InSight science image has lifted the lander’s rover arm off the drill hole and taken a new series of images in an effort to discover what caused the mole to pop out during its most recent drilling effort.

The image to the right, cropped to post here, was the first in a short movie made from all the images taken over the course of a day. The sequence shows the change in shadows, which helps define the situation in the hole.

This image however I think tells all. It shows that the walls of the hole have collapsed all around the mole, widening it further. It also shows that, once the mole popped out to lean sideways against the left wall, much of that material then fell into the hole, refilling it. These facts are very evident when today’s image is compared with this image from October, taken prior to the most recent drilling effort. The hole has become much wider, there is more material inside it, and the mole is now much farther out.

All these facts bode ill for the mole ever succeeding in drilling down the planned fifteen or so feet to insert a heat probe into the interior of Mars in order to take the first ever measure of the planet’s interior.

An overall assessment of this NASA mission is not very positive. The contribution from its international partners is especially bad. The mission was launched two years late because the French effort to build the seismometer failed. NASA had to subsequently give the job to JPL to get it done. Now the heat sensor is a failure, because the German-built mole has failed to get the heat sensor where it needs to be.

The seismometer and heat sensor were InSight’s only science instruments. This means that we will likely only get results from one.

Share

How to safely watch the November 11 solar transit of Mercury

Link here. The last transit of the Sun by Mercury was in 2016, and the next won’t be until 2032.

The site emphasizes the most important fact: Do not watch this without the proper eye protection! If you fail to heed this warning you will likely go blind, for the rest of your life. However, if you follow the instructions and obtain the proper filters, you can watch most safely.

Share

White House: Cost for each SLS launch is $2 billion

According to the Office of Management and Budget (OPM), the cost for each SLS launch is now estimated to equal $2 billion.

This is the first time anyone in the executive branch has put a number to the SLS per launch cost. NASA has always refused to give a number, for good reason, since this price compares so horribly with even the most expensive private rocket (generally more than $200 million for the biggest members of the Delta rocket family). The Falcon Heavy costs about $100 million, so that to get the same mass into orbit would require two launches, but that would still be only $200 million, one tenth the cost.

The article then notes how this cost is affecting the Europa Clipper mission, which has three launch options, with SLS mandated by Congress.

The powerful SLS booster offers the quickest ride for the six-ton spacecraft to Jupiter, less than three years. But for mission planners, there are multiple concerns about this rocket beyond just its extraordinary cost. There is the looming threat that the program may eventually be canceled (due to its cost and the emergence of significantly lower cost, privately built rockets). NASA’s human exploration program also has priority on using the SLS rocket, so if there are manufacturing issues, a science mission might be pushed aside. Finally, there is the possibility of further developmental delays—significant ground testing of SLS has yet to begin.

Another option is United Launch Alliance’s Delta IV Heavy rocket, which has an excellent safety record and has launched several high-profile missions for NASA. However, this rocket requires multiple gravity assists to push the Clipper into a Jupiter orbit, including a Venus flyby. This heating would add additional thermal constraints to the mission, and scientists would prefer to avoid this if at all possible.

A final possibility is SpaceX’s Falcon Heavy rocket, with a kick stage. This booster would take a little more than twice as long as the SLS rocket to get the Clipper payload to Jupiter, but it does not require a Venus flyby and therefore avoids those thermal issues. With a track record of three successful flights, the Falcon Heavy also avoids some of the development and manufacturing concerns raised by SLS vehicle. Finally, it offers the lowest cost of the three options.

The fact that Congress is requiring the use of SLS for a cost of $2 billion, a rocket that might not even be ready in time, when Europa Clipper could be launched on two other already operational rockets at about a tenth of the cost illustrates well the overall corruption and incompetence that permeates Congress. They really aren’t interested in the interests of the nation. They’d rather distribute money to big contractors and local interests, even if it costs the taxpayer billions and risks the mission’s success.

Share

Sightseeing Central Butte on Mars

Central Butte in foothills of Mt Sharp

Overview showing perspective of panorama

Curiosity has now roved to the very foot of Central Butte, where it has been taking close-up and panorama images of the butte and its geological layers. The panorama above was created from three Curiosity navigation images taken on Sol 2577 (November 6, 2019), here, here, and here.

The overview on the right, based on Curiosity’s position about ten sols ago slightly farther from the butte, still indicates roughly with the yellow lines the area photographed in this panorama. The dotted red line indicates Curiosity’s initial planned route.

Following that route Curiosity will eventually climb up onto the plateau beyond this butte, approaching that higher terrain farther to the west. Once they do, however, they will no longer have access to the geological layers below the surface. Central Butte gives them a window into those layers, which is why they are going to spend some time at this location, first by taking a few sols looking at the butte at this point, then circling around to study its back side.

Share

NASA to fly more year-plus missions to ISS

Leaving Earth: In an effort to shift the research focus on ISS toward learning how to do interplanetary missions, NASA wants to fly more year-plus missions to the station.

Crewmembers usually spend about six months aboard the ISS before coming back down to Earth. But that’s far shorter than a Mars mission would be; the trip to the Red Planet takes eight to nine months one way with current propulsion technology. So, NASA wants more data about the effects of long-duration spaceflight on the physiological and psychological health of astronauts. (The ISS isn’t a perfect Mars analog in this respect, of course; it resides within Earth’s protective magnetosphere and is therefore exposed to less-damaging radiation than a Mars-bound craft would be.)

To date, the agency has launched just one yearlong ISS mission, sending Scott Kelly to live on the orbiting lab from March 2015 to March 2016. Russian cosmonaut Mikhail Korniyenko took part in this flight as well, spending 342 days in space, just like Kelly. NASA has also extended two other astronauts’ ISS stays into the “Mars transit” range: Peggy Whitson racked up 289 days of continuous flight in 2016 and 2017, and Christina Koch, who arrived on the orbiting lab in March, is now scheduled to come down in February 2020.

But these three data points aren’t enough, said [Julie Robinson, NASA’s chief scientist for the ISS Program],. “What we’re saying now is we want to really bump that up a notch and add 10 more subjects to that U.S. database,” she said.

The ISS Program has approved that plan, which NASA can start implementing once a private astronaut taxi is up and running, Robinson added.

NASA should have been doing this from the beginning, The Russians have always wanted to do longer missions, and have been frustrated by NASA’s resistance. That the agency is now pushing to focus ISS research on learning how to do interplanetary travel is wonderful news. It means that we will finally be using ISS properly.

Share

TESS completes 1st survey of southern sky

The TESS science team today released its first full panorama of the southern sky, revealing everything the space telescope has imaged since launch in one image.

The glow of the Milky Way — our galaxy seen edgewise — arcs across a sea of stars in a new mosaic of the southern sky produced from a year of observations by NASA’s Transiting Exoplanet Survey Satellite (TESS). Constructed from 208 TESS images taken during the mission’s first year of science operations, completed on July 18, the southern panorama reveals both the beauty of the cosmic landscape and the reach of TESS’s cameras. “Analysis of TESS data focuses on individual stars and planets one at a time, but I wanted to step back and highlight everything at once, really emphasizing the spectacular view TESS gives us of the entire sky,” said Ethan Kruse, a NASA Postdoctoral Program Fellow who assembled the mosaic at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.

Within this scene, TESS has discovered 29 exoplanets, or worlds beyond our solar system, and more than 1,000 candidate planets astronomers are now investigating.

A reduced version of this image wouldn’t show anyone its beauty or significance. I have embedded below the fold the short video at the link which shows it quite nicely. The video also summarized the mission quite well.
» Read more

Share

U.S. formally begins exit from Paris climate agreement

On Monday the Trump administration fulfilled one of Trump’s campaign promises and formally began the year-long process to exit the Paris climate agreement.

Secretary of State Mike Pompeo announced the move in a statement. “President Trump made the decision to withdraw from the Paris Agreement because of the unfair economic burden imposed on American workers, businesses, and taxpayers by U.S. pledges made under the Agreement,” Pompeo said. “The United States has reduced all types of emissions, even as we grow our economy and ensure our citizens’ access to affordable energy….The U.S. approach incorporates the reality of the global energy mix,” he added, arguing “innovation and open markets” will drive emissions reductions.

There is ample data that indicates the U.S. is beating the targets of the Paris accord, even though Trump made it clear very shortly after taking office that the government would no longer require its implementation.

The article is amusing in its biased effort to provide a soapbox for every special interest (from environmentalists to Democrats) to express their horror at Trump’s decision. Like most
mainstream outlets, it devotes practically no effort to give the whole story.

Share

Interstellar space, as seen by both Voyager spacecraft

Today a suite of new science papers were published outlining what scientists learned when Voyager 2 joined Voyager 1 in interstellar space last November.

The Sun’s heliosphere is like a ship sailing through interstellar space. Both the heliosphere and interstellar space are filled with plasma, a gas that has had some of its atoms stripped of their electrons. The plasma inside the heliosphere is hot and sparse, while the plasma in interstellar space is colder and denser. The space between stars also contains cosmic rays, or particles accelerated by exploding stars. Voyager 1 discovered that the heliosphere protects Earth and the other planets from more than 70% of that radiation.

The data also shows that Voyager 2, which exited the heliosphere somewhat perpendicular to its direction of travel, is still in the transitional zone between the heliosphere and interstellar space. Voyager 1 exited out the head of the heliosphere, so its transitional zone was compressed and shorter.

The real achievement of these results however is that they were obtainable at all. For both spacecraft to be functioning so well after forty years in space, and able to get their data back to Earth from distances more than 11 billion miles, is a true testament to the grand engineering that went into their design and construction.

They built well in the mid-twentieth century.

Share

Sunspot update October 2019: Sunspot activity continues to flatline

For the fifth month in a row the Sun has produced practically no sunspots, possibly the longest such stretch since astronomers began recording the sunspot cycle in the 1700s.

This flatlining is very obvious in NOAA’s October update of its graph showing the long term sunspot activity of the Sun, released yesterday, and posted below, with annotations:

October 2019 sunspot activity
The graph above has been modified to show the predictions of the solar science community for the previous solar maximum. 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, extended in November 2018 four years into the future.

SILSO October graph

As it has done in previous four months, in October the Sun produced practically no sunspots. The graph on the right, produced by Sunspot Index and Long-term Solar Observations (SILSO), shows only one weak sunspot at the beginning of October.

Even though the previous 2008-2009 solar minimum was one of the deepest and longest ever recorded, the lack of sunspots in the past five months has significantly beaten it for inactivity, as shown on the first graph above. That previous minimum never had a period of even two months with so few sunspots. Furthermore, the Sun has now been blank 74% of the time in 2019, a record of blankness that beats the yearly record of either 2008 or 2009. If the Sun continues to be as blank as it has been for the next two months, 2019 will easily set the record for the year with the fewest sunspots ever recorded.

The big question remains: Are we heading for a grand minimum with no sunspots for decades? We still do not know. Even these unprecedented trends prove nothing, as we really do not yet have a clear understanding of why the Sun undergoes these various cycles of sunspot activity/inactivity. The Sun could still come back to life in the coming years. We can only wait and see. As I noted however in last month’s sunspot update, the arrival of a new grand minumum, the first since the 1600s, could have important consequences:

During past grand minimums there is evidence that the Earth also cooled, though the link between the two phenomenon remains circumstantial and unproven. If we see another grand minimum, and the Earth once again cools, then we might be able to finally tie these two phenomenon together.

It is essential that climate scientists pursue this question. Answering it might very well defuse the fears presently expressed by leftist politicians and the leftist press of an oncoming period of global warming.

At the same time, it might also present us with the possibility of an oncoming period of significant global cooling, during which it will be so cold that we might face crop failures (as happened in the previous grand minimum in the 1600s).

We need to know what is going on with the Sun, and its consequences for Earth, as soon as possible. Whether we can find out this solar cycle is unlikely, but a cold hard look at the data would do much to answer the question.

I wonder however if there any climate scientists around willing to do so. Questioning human-caused global warming carries great career risks. In fact, taking any position counter to the prevailing wisdom on any scientific issue appears to carry risks, as demonstrated by the experience recently when a journal decided to publish a paper that questioned modern gender politics:
» Read more

Share

Webb telescope faces more schedule risks, engineering issues

Even as NASA touts the final assembly of the James Webb Space Telescope, its program director noted in a presentation that the telescope is still facing several engineering issues that could cause further launch delays.

They presently are targeting a March 2021 launch on an Ariane 5 rocket (ten years behind schedule). Their schedule cushion (the extra time built into their schedule in case they have problems) however has shrunk from nine months to only two. Worse, there remain several lingering unsolved engineering problems.

One such problem is with an electronics unit called a command telemetry processor that malfunctioned during environmental testing. Robinson said engineers had problems duplicating the problem to determine the root cause and plan to replace the unit, along with a traveling wave tube amplifier used in the spacecraft’s communications system that also failed during testing.

NASA has also been working with launch provider Arianespace about concerns that residual pressure within the payload fairing at the time of fairing separation could “over-stress” the sunshield membranes. Tests on recent Ariane 5 launches confirmed that there was a higher residual pressure than the sunshield was designed for. Vents in the fairing are being redesigned to address this, Robinson said, and will be tested on Ariane 5 launches in early 2020.

However, those smaller problems, along with bigger issues like fastener problems with the sunshield found during environmental testing last year, have eroded the margin built into the revised schedule for the mission.

Unmentioned in the article is the fact that Arianespace is planning to retire the Ariane 5 when its Ariane 6 starts launching next year. Right now they have agreed to maintain their Ariane 5 launch facilities through March 2021 to allow Webb’s launch, but further delays could cause significant problems, including fixing the fairing issue mentioned above. At a certain point Arianespace will no longer be willing to hold onto Ariane 5 for just this one launch.

Also unmentioned in the article is the status of Webb’s budget, which has grown from a proposed $500 million cost to almost $10 billion. I suspect that if they can meet their March 2021 launch date that total will not grow much. Any further delays however will once again cause it to balloon.

(I originally listed the proposed cost of Webb above as $1 billion, but that number is wrong. See the comments below).

Share

Jupiter’s thunderheads

The cloud tops of Jupiter
Click for full image.

Using raw Juno images, citizen scientist Gerald Eichstädt has created the processed and color enhanced image to the right, cropped to post here. From the Juno press release:

This view from NASA’s Juno spacecraft captures colorful, intricate patterns in a jet stream region of Jupiter’s northern hemisphere known as “Jet N3.”

Jupiter’s cloud tops do not form a simple, flat surface. Data from Juno helped scientists discover that the swirling bands in the atmosphere extend deep into the planet, to a depth of about 1,900 miles (3,000 kilometers). At center right, a patch of bright, high-altitude “pop-up” clouds rises above the surrounding atmosphere.

Some of the darker areas are darker mostly because they are lower and therefore in shadow.

The raw image was taken on May 29, 2019 when Juno was about 6,000 miles away. Unfortunately, they do not provide a scale, but I suspect that the image is probably close to the size of the entire Earth.

Share

Smallest spherical planet so far found

Hygiea

A new image of the asteroid Hygiea has revealed that this main belt object is actually spherical, making it the smallest spherical asteroid so far discovered and suggesting that it could be defined as a planet.

The image, taken by the Very Large Telescope (VLT) in Chile, is to the right. The asteroid was first discovered in 1849 and is the fourth largest in the asteroid belt, after Ceres, Pallas, and Vesta, with a diameter of 267 miles.

The image once again challenges the definition of what makes a planet. It also makes difficult the vague term “dwarf planet.” At what point does a dwarf become a full planet? This has never been clarified, which is why I tend to avoid using the term dwarf planet.

In my many interviews of planetary scientists, they generally dismiss the IAU’s poor definition of a planet and define a planet as anything that has settled into a spherical shape. In the case of Hygiea, that seems to apply.

Share

Rover update: October 28, 2019

Summary: Curiosity finally on the move after several months drilling two adjacent holes in the clay unit. Yutu-2 continues roving west, has it now operates during its eleventh lunar day on the far side of the Moon.

For the updates in 2018 go here. For a full list of updates before February 8, 2018, go here.

Curiosity's present location in Gale Crater
Click for original full image.

Curiosity

For the overall context of Curiosity’s travels, see my March 2016 post, Pinpointing Curiosity’s location in Gale Crater.

I have not done any of my regular rover updates since May 30, 2019 because it was simpler to do individual updates for both Curiosity and Yutu-2, the only working rovers presently on other worlds. (If things had gone well, which they did not, we would have had two other lunar rovers in the past six months, one from Israel and one from India, but both crashed during landing.)

However, since Curiosity is finally on the move after spending several months at one location, where it drilled two holes in the clay unit (the material from one used in a wet cup experiment to look for organic life) it is time to update my readers on where Curiosity is and where it is heading.

The first image above and to the right is an annotated overview of Curiosity’s present position, moving south to a line of buttes which scientists have determined delineates the transition from the clay unit to a new geological layer they have dubbed the Greenheugh Pedimont. The yellow lines indicate the area seen in the panorama below, created from two photographs (here and here) taken by the rover’s navigation camera.
» Read more

Share

InSight’s mole has popped out of its hole

InSight's mole, out of the ground
Click for full image.

In a setback for its renewed digging effort, the mole drill on InSight has apparently bounced out of its drilled hole during the most recent drilling, soon after engineers had increased the rate of hammer strokes.

The image to the right shows the mole, the white cylinder on the left, with the scoop of the robot arm mostly covering the hole in its effort to pin the mole in position.

“While digging this weekend the mole backed about halfway out of the ground,” the mission announced via a pair of tweets Oct. 27. “Preliminary assessment points to unexpected soil properties as the main reason.”

…The mission added that one possibility is soil is falling in front of the mole, filling the hole. “Team continues to look over the data and will have a plan in the next few days.”

Without question the alien and fluffy properties of the soil appears to be the problem. Based on how the mole is leaning, I wonder if the left wall of the hole began to widen and collapse, as had the rest of the hole during initial drilling, thus defeating the purpose of the robot arm’s effort to pin the mole in place.

Share
1 2 3 4 173