Tag: science

First images from Chandrayaan-2

8:29 am

Earth from Chandrayaan-2

India yesterday released the first images taken by its lunar orbiter/lander/rover Chandrayaan-2, taken from Earth orbit of the Earth.

The image on the right is one example, and was taken mostly for engineering purposes. All the images (available here) demonstrates that the spacecraft’s camera is working properly, and it can orient itself accurately.

They now hope to put the spacecraft into lunar orbit on August 20th, with the landing attempt set for September 7th, after they have lowered that lunar orbit sufficiently.

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The Milky Way is warped?

9:56 am

Warped Milky Way

Astronomers mapping the locations of one kind of variable star in the Milky Way have found that, based on that data, our galaxy appears to be warped.

To make the map, astronomers looked to its bright, pulsing stars called cepheids. These stars burn up to 10,000 times more brightly than the sun so they are visible from across the galaxy and through interstellar clouds of gas and dust. Crucially, cepheids are “standard candles”: Their light waxes and wanes at a rate that corresponds to their inherent brightness. Astronomers can combine their true brightness with their apparent brightness, measured from Earth, to calculate how far away they are. Using a 1.3-meter telescope at Las Campanas Observatory in Chile, astronomers monitored the steady pulses from more than 2400 stars and pinpointed their location on a 3D model of the galaxy.

…From above, the Milky Way can be seen as a spiral-shaped galaxy, but this spiral disk doesn’t sit flat on the galactic plane. The cepheid stars cluster along an S-shaped curve, showing that the Milky Way’s disk is more warped than previously thought.

The image above shows this warp, with the star indicating where the Sun is located. The green dots represent cepheid variable stars.

Top view of galaxy

This science is good, but there are uncertainties. For example, a top view of the galaxy, showing the location in yellow of all the cepheids mapped, is to the right. Notice the strong bias to one side of the galaxy, where the Sun is located. Their information for the rest of the galaxy is very spotty.

The available data might show this warp, but I think it is premature to assume it accurately maps the entire shape of the Milky Way.

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Parker data downloaded from first two orbits

9:28 am

The science team for the Parker Solar Probe has completed the download of all data gathered during the spacecraft’s first two solar orbits.

On May 6, 2019, just over a month after Parker Solar Probe completed its second solar encounter, the final transmission of 22 gigabytes of planned science data — collected during the first two encounters — was downlinked by the mission team at the Johns Hopkins Applied Physics Laboratory, or APL, in Laurel, Maryland.

This 22 GB is 50% more data than the team had estimated would be downlinked by this point in the mission — all because the spacecraft’s telecommunications system is performing better than pre-launch estimates. After characterizing the spacecraft’s operations during the commissioning phase, which began soon after launch, the Parker mission team determined that the telecom system could effectively deliver more downlink opportunities, helping the team maximize the download of science data.

The team has capitalized on the higher downlink rate, instructing Parker Solar Probe to record and send back extra science data gathered during its second solar encounter. This additional 25 GB of science data will be downlinked to Earth between July 24 and Aug. 15.

Don’t expect any immediate press conferences announcing results. It will take them time to analyze this batch, and they will probably want to do a few more orbits before coming to any conclusions.

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A heavy metal exoplanet, a star with no iron

9:33 am

Two strangely related astronomy stories to start the day:

The first describes a weird planet so hot that metals are gas in the atmosphere:

A scorching planet, WASP-121b orbits precariously close to a star that is even hotter than our Sun. The intense radiation heats the planet’s upper atmosphere to a blazing 4,600 degrees Fahrenheit. Apparently, the lower atmosphere is still so hot that iron and magnesium remain in gaseous form and stream to the upper atmosphere, where they escape into space on the coattails of hydrogen and helium gas.

The sizzling planet is also so close to its star that it is on the cusp of being ripped apart by the star’s intense pull. This hugging distance means that the planet is stretched into a football shape due to gravitational tidal forces.

The presence of so much heavy elements suggests this planet and star formed relatively recently in the history of the universe, after many generations of star formation made possible the creation of those elements.

The second describes a star so devoid of iron that it hints of the first stars that ever formed.

The very first stars in the Universe are thought to have consisted of only hydrogen and helium, along with traces of lithium. These elements were created in the immediate aftermath of the Big Bang, while all heavier elements have emerged from the heat and pressure of cataclysmic supernovae – titanic explosions of stars. Stars like the Sun that are rich in heavy element therefore contain material from many generations of stars exploding as supernovae.

As none of the first stars have yet been found, their properties remain hypothetical. They were long expected to have been incredibly massive, perhaps hundreds of times more massive than the Sun, and to have exploded in incredibly energetic supernovae known as hypernovae.

The confirmation of the anaemic SMSS J160540.18–144323.1, although itself not one of the first stars, adds a powerful bit of evidence.

Dr Nordlander and colleagues suggest that the star was formed after one of the first stars exploded. That exploding star is found to have been rather unimpressive, just ten times more massive than the Sun, and to have exploded only feebly (by astronomical scales) so that most of the heavy elements created in the supernova fell back into the remnant neutron star left behind.

Only a small amount of newly forged iron escaped the remnant’s gravitational pull and went on, in concert with far larger amounts of lighter elements, to form a new star – one of the very first second generation stars, that has now been discovered.

All the the science and data with both stories is highly uncertain. Both however point to the complex and hardly understood process that made us possible.

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LightSail-2 successfully raises its orbit using sunlight

3:25 pm

Capitalism in space: By raising its orbit by the use of sunlight only, LightSail-2 has confirmed what an earlier Japanese solar sail Ikaros had demonstrated, that it is possible to use solar sails to travel in space.

Since unfurling the spacecraft’s silver solar sail last week, mission managers have been optimizing the way the spacecraft orients itself during solar sailing. After a few tweaks, LightSail 2 began raising its orbit around the Earth. In the past 4 days, the spacecraft has raised its orbital high point, or apogee, by about 2 kilometers. The perigee, or low point of its orbit, has dropped by a similar amount, which is consistent with pre-flight expectations for the effects of atmospheric drag on the spacecraft. The mission team has confirmed the apogee increase can only be attributed to solar sailing, meaning LightSail 2 has successfully completed its primary goal of demonstrating flight by light for CubeSats. [emphasis mine]

The highlighted text notes a secondary but possibly more important engineering achievement here. LightSail-2 was launched as a cubesat. It has now proven that such a cubesat can include a solar sail and use it for purposes of transportation.

Moreover, that this engineering test was funded entirely by private funds proves again that the government is not necessary for great things to be achieved.

They will continue to raise the spacecraft’s apogee for the next month, until the lowering of the perigee causes the spacecraft to get pulled out of orbit by the drag from the atmosphere. That second process will still take about a year.

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More exoplanets found by TESS

9:50 am

Worlds without end: In confirming a candidate exoplanet previously discovered by TESS, astronomers have detected two more exoplanets orbiting the same star.

The transits TESS observed belong to GJ 357 b, a planet about 22% larger than Earth. It orbits 11 times closer to its star than Mercury does our Sun. This gives it an equilibrium temperature — calculated without accounting for the additional warming effects of a possible atmosphere — of around 490 degrees Fahrenheit (254 degrees Celsius). “We describe GJ 357 b as a ‘hot Earth,’” explains co-author Enric Pallé, an astrophysicist at the IAC and Luque’s doctoral supervisor. “Although it cannot host life, it is noteworthy as the third-nearest transiting exoplanet known to date and one of the best rocky planets we have for measuring the composition of any atmosphere it may possess.”

But while researchers were looking at ground-based data to confirm the existence of the hot Earth, they uncovered two additional worlds. The farthest-known planet, named GJ 357 d, is especially intriguing. “GJ 357 d is located within the outer edge of its star’s habitable zone, where it receives about the same amount of stellar energy from its star as Mars does from the Sun,” said co-author Diana Kossakowski at the Max Planck Institute for Astronomy in Heidelberg, Germany. “If the planet has a dense atmosphere, which will take future studies to determine, it could trap enough heat to warm the planet and allow liquid water on its surface.”

Without an atmosphere, it has an equilibrium temperature of -64 F (-53 C), which would make the planet seem more glacial than habitable. The planet weighs at least 6.1 times Earth’s mass, and orbits the star every 55.7 days at a range about 20% of Earth’s distance from the Sun. The planet’s size and composition are unknown, but a rocky world with this mass would range from about one to two times Earth’s size.

Even through TESS monitored the star for about a month, Luque’s team predicts any transit would have occurred outside the TESS observing window.

I think the results from TESS are soon going to overwhelm the general press. I myself had to check and make sure this story was about different exoplanets than the previous exoplanet discovery story from two days ago.

What is most interesting about these new exoplanets is their mass and size. TESS appears so far to be finding a lot of superEarths, something that Kepler did not do.

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A bullseye on Mars

1:57 pm

Layered crater at equator
Click for full image.

Cool image time! In researching my piece last week on the glaciers of Mars I had wanted to include a picture of a typical concentric glacier-filled crater, the most widespread glacial feature on the Martian surface, found in a band at latitudes between 30 and 60 degrees. (You can see the example I found at the link above, near the end of the article.)

To find that picture I searched the Mars Reconnaissance Orbiter (MRO) archive. Among the images I found was a captioned image taken very early in MRO’s mission showing a crater with concentric rings very similar to the concentric glacial-filled craters. The image at the right is that crater, the image reduced and cropped to post here. As described in that caption,
» Read more

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TESS completes survey of southern hemisphere

6:36 pm

The space telescope TESS has completed its first year in orbit, surveying the entire southern hemisphere for transient events.

NASA’s Transiting Exoplanet Survey Satellite (TESS) has discovered 21 planets outside our solar system and captured data on other interesting events occurring in the southern sky during its first year of science. TESS has now turned its attention to the Northern Hemisphere to complete the most comprehensive planet-hunting expedition ever undertaken.

TESS began hunting for exoplanets (or worlds orbiting distant stars) in the southern sky in July of 2018, while also collecting data on supernovae, black holes and other phenomena in its line of sight. Along with the planets TESS has discovered, the mission has identified over 850 candidate exoplanets that are waiting for confirmation by ground-based telescopes.

It is important to emphasize that these are candidate exoplanets. They still need to be confirmed by other observations.

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University punishes professor for uncovering academic fraud and incompetence

10:17 am

Portland State University (located in that hotbed of antifa fascist violence) has announced that it is punishing one of its professors for uncovering academic fraud and incompetence by co-writing several fake science papers and getting them published.

Peter Boghossian made headlines in 2018 after he and two other researchers set out to prove a point about the integrity of “peer-reviewed” academic publications by submitting several fake studies including an analysis of “dog rape culture,” and a piece that was simply a section of Hitler’s Mein Kampf reworked to include a smattering of academic buzzwords. After seven of the team’s fake submissions were accepted and published by esteemed academic journals, a Campus Reform investigation led the publisher of the infamous Portland “dog park rape culture” article to question the origins of the submission. This ultimately revealed the article as part of a larger effort by Boghossian and his team to demonstrate the inadequacies of these publications.

After his experiment, Portland State threatened Boghossian with disciplinary action, accusing him of conducting research misconduct. The school asserted that Boghossian had unethically conducted research on human subjects with his experiment. According to the school’s Institutional Review Board, Boghossian would have needed to obtain “informed consent” from the individuals reviewing his hoax articles in order for his actions to have been considered ethical.

The IRB conducted several reviews of Boghossian’s work involving his treatment of animal subjects, human subjects, and the possibility of “plagiarism, fabrication, and falsification.” On July 17, the university sent Boghossian a letter informing him that he is now barred from conducting any “human subjects related research,” as well as any university-sponsored research. Boghossian is prohibited from conducting research until he “can show satisfactory evidence of understanding of the protections afforded human subjects,” by completing a “protection of human subjects” training course and subsequently meeting with the Assistant Vice President for Research Administration to “assure [his] understanding.”

The letter, sent from Vice President for Research and Graduate Studies Mark McLellan, also warns Boghossian that the university president, as well as his department chair, dean, and provost, will be advised as to his “lack of academic integrity” and “questionable ethical behavior.”

This story is closely related to the Oberlin story below. Both universities are typical modern leftist madhouses, dominated by fake and politically driven academics who will brook no dissent. They are also increasingly bigoted against ordinary white Americans, merely because they are white. Boghossian and his cohorts did the academic community a service by identifying journals where bad research was being routinely published. His university immediately moved to squelch his effort by punishing him.

Is this the kind of place you want to send your kids? Is this the kind of place you’d want to attend, if you were a high school student?

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Chandayaan-2 completes first orbit burn

8:18 am

India’s lunar orbiter/lander/rover Chandrayaan-2 yesterday completed its first orbital engine burn, raising its apogee, the high point in its orbit, 6,000 kilometers to about 51,000.

This boost meant that Isro scientists have to perform one less manoeuvre in the Earth orbit than what was planned earlier. According to the path chalked out for Chandrayaan-2 before the launch, the on-board propulsion systems were to be fired six times in Earth orbit – five times to raise the apogee and once to raise the perigee. Now, only four more “burns”, or firing of the propulsion system, will be needed on July 26 and 29, and August 2 and 6, to reach the final orbit of 233.2 x 143,953km.

…With a final boost on On August 14, Chandrayaan-2 will escape Earth’s orbit and begin its seven-day journey towards the moon. The spacecraft is scheduled to reach the moon orbit on August 20.

Once in lunar orbit they plan four more burns to lower the spacecraft to a 100 kilometer circular orbit, where the lander/rover will release and begin their own lowering process aimed for a September 7 landing.

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End coming for twin Van Allen spacecraft

8:07 am

Engineers at the Applied Physics Lab in Maryland on July 19 turned off one of the two Van Allen probes, with the second probe expected to receive a similar command later this year.

As expected, following final de-orbit maneuvers in February of this year, the spacecraft has used its remaining propellant to keep its solar panels pointed at the Sun and is now out of fuel. Since it depends on the Sun to provide power to the instruments, and can no longer orient itself to acquire power, the spacecraft has been turned off. The spacecraft is in a stable, circular orbit around Earth and, in about 15 years, will re-enter the atmosphere and burn up safely. The de-orbit maneuvers in February were designed to ensure this would happen and prevent the spacecraft from becoming “space junk” in orbit.

The other Van Allen Probes spacecraft, spacecraft A, is expected to operate normally until early September.

Both spacecraft functioned five years longer than expected, and during that time discovered that there are three Van Allen belts, not two as previously thought.

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Possibility of meteorites from bright fireball in Ontario

1:54 pm

Astronomers were successfully able to track and photograph a bright fireball over Canada early today, and think it is strongly possible that pieces of it might have hit the ground.

Preliminary results indicate that the fireball first became visible just south of Oshawa over Lake Ontario at an altitude of 93 km. It traveled over Clarington and passed just west of Peterborough before extinguishing just west of Bancroft. The fireball rivaled the full moon in brightness and had a number of bright flares near the end of its flight. The meteoroid was roughly the size of a small beachball (approx. 30cm in diameter) and likely dropped a small number of meteorite fragments in the tens to hundreds of grams size-range on the ground.

Brown and his collaborators at Western and the Royal Ontario Museum are interested in connecting with people from the area of the potential fall, who may have heard anything unusual, or who may have found possible meteorites.

…Meteorites can be recognized by their dark, often scalloped exterior. Usually they will be denser than a ‘normal’ rock and will often be attracted to a magnet due to their metal content. Meteorites are not dangerous, but if recovered, it is best to place them in a clean plastic bag or wrap them in aluminum foil. They should also be handled as little as possible to help preserve their scientific value. In Canada, meteorites belong to the owner of the land upon which they are found. If individuals plan to search, they should always obtain permission of the land-owner before venturing onto private land.

If you live up in that neck of the woods, take a look around. You might find something.

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The glaciers of Mars

11:24 am

The glaciers on Mars

For the future colonists of Mars, the question of finding water will not be that much of a problem. Not only have planetary geologists mapped out the existence of extensive water-ice in the Martian poles, they have found that the planet apparently has widespread glacier deposits in two mid-latitude belts from 30 to 60 degrees latitude.

The question will be whether those Martian settlers will be able to easily access this water. The data so far suggests that much of the Martian underground water at high latitudes is likely mixed with dust and debris. Extracting it might not be straightforward. There are hints that the ice table at latitudes about 55 degrees might be more pure, but could be somewhat deep below ground, requiring the settlers to become miners to obtain their water. Moreover, all these high latitude locations are in environments that are more hostile, and therefore more difficult to establish a colony.

What about the glaciers? The global map of Mars above, reduced and annotated to post here, shows what are believed to be extensive glacial deposits at lower latitudes, and comes from a recently published paper on the subject. The different colors indicate the different types of glacial deposits the scientists have identified.

Green and yellow indicate what scientists call lineated valley fill (LVF) and lobate debris aprons (LDA) respectively, glacial deposits found in the transition zone between the southern highlands and either the northern lowland plains or the basins of the southern hemisphere, Hellas and Argyre. These glaciers are in many ways most similar to glaciers found on Earth, flows heading downhill along natural geographic features.

Magenta represents concentric crater fill (CCF), glacier features which seem very evenly distributed across both the northern and southern lower mid-latitude belts. Here scientists appear to have detected buried ice within the floors of craters.

The paper which included this map focused on describing a new glacial feature, something they dubbed valley fill deposits (VFD), that they had found so far in only one place, as indicated by the black square on the map.

The photograph below and on the right, reduced and cropped to post here, is from figure two of the linked paper.
» Read more

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Tsunamis on Mars?

8:54 am

New research has found further evidence of past tsunamis on Mars along the transition zone between the northern lowlands (where an intermittent ocean might have once existed) and the southern highlands, caused when a bolide crashed into that ocean.

The new research simulated the height of the tsunami waves and their propagation direction, run-up elevation and distance for three potential sea levels and compared these models with the Martian deposits.

The study’s results suggest several potential impact craters, 30 to 50 kilometers (19 to 31 miles) in diameter, as the source of the tsunami events. The largest tsunami waves may have been 300 meters (984 feet) high – nearly as tall as the Eiffel Tower – following the impact, and waves up to 75 meters (246 feet) high – nearly as tall as the Statue of Liberty. The waves ultimately reached the Martian coast, potentially traveling up to 150 kilometers (93 miles) past the shoreline.

Below the fold is a video showing the simulation of one such impact and tsunami.
» Read more

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Jackson Crater on the Moon’s far side

11:01 am

Jackson Crater

Central peaks of Jackson Crater

In celebration of the 50th anniversary of the Apollo 11 mission, let’s look at another cool Moon photograph. The Lunar Reconnaissance Orbiter (LRO) science team on July 19 released a new breath-taking oblique image of Jackson crater, located on the Moon’s far side. The image above, reduced significantly to post here, shows that photograph and the crater’s cluster of near-center peaks. From the caption:

East-to-west view of Jackson crater (44 miles diameter). Image was acquired when LRO was at an altitude of [69 miles] and the Sun was to the west of the crater (LROC was facing somewhat towards the Sun; phase angle 114 degrees). The central peak rises about [5900 feet] above the crater floor and the top of the crater rim in the background has more than [13,000 feet] relief relative to the floor. Image width is about [40 miles] and north is to the right

The white box indicates the area covered by the close-up to the right. From the article:

What is the composition of the crust from top to bottom? It is relatively easy to measure the surface, but what lies beneath the surface? On the Earth geologists can dig and drill deep into the crust. We do not have that luxury on the Moon, at least not yet! However, we can take advantage of natural drill holes in the crust – impact craters! When impacts occur they dig into the crust and the central peaks expose the deepest material. Jackson crater formed on what was rather uneven terrain: to the east of the crater the elevation is about +6000 meters and to the west about +3000 meters. The bottom of the crater sits at +1000 meters, and the material exposed in the central peak comes from more than 1000 meters deeper still. By studying the rocks exposed in the central peak we can get a glimpse of materials that have come up from five or more kilometers below the surface (>3 miles).

The black pile of giant boulders near the top of the close-up suggests molten material dredged up from deep below the surface. So do the many black boulders on the nearer mountain slopes.

Why this dark material does not cover the entire surface is not clear. The lighter and darker material indicates different materials and ages, but the specifics are not known, as yet.

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India successfully launches Chandrayaan-2

8:24 am

The new colonial movement: India yesterday successfully launched its lunar orbiter/lander/rover Chandrayaan-2 into orbit.

India’s Geosynchronous Satellite Launch Vehicle GSLV MkIII-M1, successfully launched the 3840 kg Chandrayaan-2 spacecraft into an earth orbit today (July 22, 2019). The spacecraft is now revolving round the earth with a perigee (nearest point to Earth) of 169.7 km and an apogee (farthest point to Earth) of 45,475 km. Today’s flight marks the first operational flight of the GSLV Mk III.

They will slowly raise the spacecraft’s apogee over the next two months to bring it into the Moon’s gravitational sphere of influence, when they will begin lowering the orbit leading to a separation of the lander/rover for a September 7 landing near the Moon’s south pole.

This was the third launch of the upgraded GSLV Mark III. With this launch India now has an operational rocket it can use to launch its astronauts into space in 2022.

The leaders in the 2019 launch race:

9 China
9 Russia
8 SpaceX
5 Europe (Arianespace)
4 India

The U.S. continues to lead in the national rankings, 14 to 9.

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The Untouched Moon

6:01 pm

Montes Carpatus
Click for full image.

In celebration of Apollo 11: Continuing the theme of yesterday’s cool image, where I noted how little of the Moon we have really seen, today’s cool image gives us a breath-taking glimpse of one such untouched region, the Montes Carpatus region.

The photograph to the right, reduced to post here, was released by the Lunar Reconnaissance Orbiter (LRO) science team in March 2018. From the release:

Volcanic rocks are our best window to the deep interior of the Moon, and the Montes Carpatus has no shortage of volcanic landforms: lava flows, pyroclatic deposits, rilles, and more! Lavas are formed as the mantle begins to melt, so by sampling volcanic rocks of various ages from regions across the Moon scientists can reconstruct the range of compositions and processes over time. The Montes Carpatus formed as a result of the giant impact that formed the mighty Imbrium basin, the mountains are actually the raised rim of the basin.

Today is the 50th anniversary of the Apollo 11 landing. If you had told anyone involved in that mission that fifty years later no significant further manned exploration of the Moon had yet occurred, they would have scoffed.

It is a terrible condemnation of my generation, the generation that followed Apollo 11, that we did nothing grand like this. I challenge the generations today to reach higher, and do better.

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The Taurus-Littrow valley

6:01 pm

Taurus-Littrow Valley
Click for full image.

It might not be Apollo 11, but during this 50th anniversary week of that mission, why not look at where the last Apollo 17 crew landed, in the middle of the Taurus-Littrow valley, as shown on the right in a Lunar Reconnaissance Orbiter (LR) image released by the LRO science team in 2018.

The image illustrates how ambitious NASA had become by this last Apollo mission. The Apollo 11 site was chosen because it was flat with as few risks as possible. By Apollo 17, the Apollo engineers and astronauts were quite willing to drop the LM down into this valley between gigantic mountains. Granted, the valley was more than 400 miles wide, but considering the risks of every Apollo flight, the choice was daring to say the least.

Taurus-Littrow also has a cluster of craters believed to have been formed by material flung out from the formation of 86-kilometer-wide Tycho crater about 100 million years ago. Tycho is 2250 kilometers from Taurus-Littrow, but the impact that formed it was violent enough that it cast material far across the Moon.

Nor is this location the most spectacular on the Moon. In fact, considering that all the manned and unmanned missions in total have probably covered less ground than a New York cab driver does in a single day, we have seen almost nothing there.

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A wave on the Moon

3:01 pm

A lunar ejector blanket

Continuing this week’s celebration of the 50th anniversary of the Apollo 11 mission means we get to look at another cool image from the Moon. The photograph on the right, reduced to post here, was released by the Lunar Reconnaissance Orbiter (LRO) science team in 2016.

What are we looking at? At first glance it looks like a black & white photograph of The Wave in northern Arizona. What it is instead is the pattern of ejecta laid down across the surrounding terrain immediately after the impact that created relatively fresh Chaplygin Crater. From the website:

The delicate patterns of flow across, over, and down local topography clearly show that ejecta traveled as a ground hugging flow for great distances, rather than simply being tossed out on a ballistic trajectory. Very near the rim lies a dark, lacy, discontinuous crust of now frozen impact melt. Clearly this dark material is on top of the bright material so it was the very last material ejected from the crater.

Below the fold is a wider shot of the entire crater and its surrounding terrain, with the rectangle indicating the region covered by the close-up above The dark crust near the rim mentioned in the quote can clearly be seen.
» Read more

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Weird lunar crater

2:58 pm

Concentric crater in Apollo Basin on the Moon

In celebration of the 50th anniversary of the Apollo 11 mission, it is time for another cool image from the Moon. The photograph on the right, reduced to post here, was taken by Lunar Reconnaissance Orbiter (LRO) in 2013. It shows a weird crater with concentric features that is found within Apollo Basin, a large 334-mile-wide double-ringed impact feature in the southern hemisphere of the Moon’s far side.

Concentric craters have an inner rim whose formation mechanism is not yet entirely understood, but the concentric mounds may indicate that there is a discontinuity, such as layers with different strengths, in the subsurface excavated by the impact.

Or to put it more bluntly, they really have no idea why this crater ended up looking as it does.

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Apollo 11 First Stage liftoff

6:01 pm

An evening pause: This was originally posted as an evening pause in 2016. I think that today, the fiftieth anniversary of the launch of Apollo 11, it is appropriate to repost it. As I wrote then,

Though the video is more than 8 minutes long, the actual events recorded lasted only about 30 seconds, beginning 5 seconds before T minus 0.

What struck me most as I watched this was the incredible amount of complex engineering that went into every single small detail of the rocket and the launch tower and launchpad. We tend to take for granted the difficulty of rocket engineering. This video will make you appreciate it again.

It is also mesmerizing. A lot happens in a very short period of time.

Tonight’s evening pause begins eight days of pauses dedicated to celebrating, and reliving, the Apollo 11 mission. To the Moon!

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A lunar crater wall two miles high

11:06 am

Giordano Bruno crater

Cool image time! Considering this week is the 50th anniversary of the Apollo 11 lunar landing, it seems appropriate to show some cool images from the Moon.

Today the Lunar Reconnaissance Orbiter (LRO) science team released a spectacular oblique image of Giordano Bruno crater. The image on the right is cropped and very significantly reduced to post here. It looks across the crater, with the near rim across the bottom of the picture and the wall of the far rim filling the photograph’s top half.

That wall is what makes this image cool. It is a cliff about 10,000 feet high, equaling almost two miles. Moreover, at its base is a now-solidified melt pool left over from the impact that made the crater.

Faster than a speeding bullet – or rather ten times faster than a speeding bullet – is a good starting point in terms of grasping the energy released in a typical impact event. That is, for a bullet approaching 2 kilometers in diameter! The pressure and heat that were released during the collision not only excavated a hole much larger than the impactor but also melted a tremendous amount the target rock. Melt was sprayed and sloshed on the forming crater walls where much of it flowed back, seeking the lowest point in the impact crater. From the LROC vantage point you can follow the path taken by impact melt as it flowed across the irregular floor, ponding in closed depressions, and some of it ultimately reaching the lowest point.

Below the fold is a much higher resolution section of this photograph, focused on the crater wall and the melt pool. I have still been forced to reduce the resolution somewhat to post it here. Along that cliff wall can be seen partial avalanches (the dark splotch near the center) as well boulder tracks with the boulders (probably larger than most houses) still visible as white spots at the wall’s base.

The scale here is difficult to imagine. This cliff wall is three times as high as The Abyss, the steepest single drop viewpoint along the south rim of the Grand Canyon.
» Read more

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Chandrayaan-2 launch scrub caused by leak in helium bottle

8:50 am

Engineers today announced that the July 14 scrub of India’s Chandrayaan-2 lunar orbiter/lander/rover was caused by a leak in a helium bottle in the GSLV rocket.

“The good news is that we can fix the leak without dismantling the rocket, since there is an access door to the gas bottle which is atop the oxygen tank,” a senior scientist told TOI. “The bad news is that unless we ascertain the reason for the leak, there is a probability of the problem recurring.” Not having to dismantle means Chandrayaan-2 may be able to fly before the end of the July launch window, but a final failure analysis will be available only in a day or two.

Sources told TOI that the leak wasn’t serious enough to impair the flight, but Isro decided to apply “abundant caution,” given the importance of the Rs 978-crore project that would make India only the fourth country – after the US, Russia and China – to land a craft on the lunar surface.

I am willing to bet that if their investigation does not pinpoint the cause of the leak in the next few days, they will stand down from the July launch window. This mission, as well as proving the reliability of their GSLV rocket, are both too important to risk on an unknown and unsolved engineering issue.

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Hayabusa-2: Carbon-rich asteroids too delicate to reach Earth surface

1:57 pm

New data from Hayabusa-2 has confirmed the long-held suspicions of astronomers that the reason they find so few fragments of C-class asteroids, such as Ryugu, on Earth is because they are too delicate to reach the Earth’s surface.

Ryugu and other asteroids of the common ‘C-class’ [chondritic] consist of more porous material than was previously thought. Small fragments of their material are therefore too fragile to survive entry into the atmosphere in the event of a collision with Earth.

…Until now, only a few chondritic meteorites found on Earth have been identified as fragments of C-type asteroids, which are very common in the Solar System (‘C’ is the chemical symbol for the element carbon). …”We can now confirm that fragments of these asteroids are very likely to break up further when they enter Earth’s atmosphere, and then usually burn up completely. This means that only the largest fragments reach the Earth’s surface,” explains Grott. “That is why meteorites from this type of asteroid are so rarely found on Earth.”

The good news is that, because of this, Earth’s atmosphere offers increased protection from C-type asteroids, which account for 75 percent of all asteroids. …However, further research is necessary to determine the maximum asteroid size for which this atmospheric protection is effective.

It is likely that even the largest rubble-pile C-asteroids will not pose much risk. Even if some pieces reach the Earth’s surface they are probably going to be small and unable to do much harm.

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Two new science papers strongly question theory of man-made global warming

9:48 pm

The uncertainty of science: Two new science papers, from researchers in Finland and Japan respectively, both strongly question the theory that human activity and the increase of carbon dioxide are causing global warming.

From the Finnish paper’s [pdf] conclusion:

We have proven that the [climate]-models used in IPCC report AR5 cannot compute correctly the natural component included in the observed global temperature. The reason is that the models fail to derive the influences of low cloud cover fraction on the global temperature. A too small natural component results in a too large portion for the contribution of the greenhouse gases like carbon dioxide. That is why 6 J. KAUPPINEN AND P. MALMI IPCC represents the climate sensitivity more than one order of magnitude larger than our sensitivity 0.24°C. Because the anthropogenic portion in the increased CO2 is less than 10 %, we have practically no anthropogenic climate change. The low clouds control mainly the global temperature. [emphasis mine]

From the Japanese paper:

“The Intergovernmental Panel on Climate Change (IPCC) has discussed the impact of cloud cover on climate in their evaluations, but this phenomenon has never been considered in climate predictions due to the insufficient physical understanding of it,” comments Professor Hyodo. “This study provides an opportunity to rethink the impact of clouds on climate. When galactic cosmic rays increase, so do low clouds, and when cosmic rays decrease clouds do as well, so climate warming may be caused by an opposite-umbrella effect. The umbrella effect caused by galactic cosmic rays is important when thinking about current global warming as well as the warm period of the medieval era.”

Essentially, both criticize the climate models for not considering changes in cloud cover and how those effect the global climate. The first paper looks back at the known climate data and compares it with known changes in cloud cover, and finds that cloud cover is a major factor in temperature changes.

The second paper looks at the causes for some of the changes in cloud cover, noting how the increase in galactic cosmic rays during the solar minimum can be tied to an increase in cloud cover, and thus colder temperatures.

Do these papers disprove man-made global warming caused by the increase in carbon dioxide in the atmosphere? Of course not. They just demonstrate again that the science here is very unsettled, that there are many large gaps in our knowledge, and that it would be foolish now to abandon western civilization and replace it with socialist totalitarian rule in order to prevent a disaster that either might not be happening, or if it is we may have no power to control.

I want to also point out that this post talks about scientists challenging the theory of man-made global warming. Attention must be paid to their conclusions. As for the ignorant opinions of politicians on this subject, who cares?

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Russia successfully launches Spektr-RG carrying two X-ray space telescopes

9:20 pm

Russia today successfully used its Proton rocket to launch Spektr-RG, carrying two X-ray space telescopes.

Spektr-RG was first conceived in the 1990s, but got shelved then because Russia did not have the money to launch it. The project got revived in 2005 when the Germans came on to build one of the two telescopes.

“We had an ambitious plan for the project which didn’t correspond to the power of the country of that moment,” [lead scientist Mikhail] Pavlinsky told Spaceflight Now. “We decided to restart it with a smaller version.”

The Russian and German space agencies signed an agreement in 2009 to jointly develop the Spektr-RG mission, but the project faced additional schedule delays due to technical problems and a decision to switch the observatory from a Zenit launcher to a Proton rocket.

Designers also changed Spektr-RG’s observing location from an orbit around Earth to a looping trajectory around the L2 Lagrange point.

Spektr-RG is the largest Russian astronomy satellite to launch since the Spektr-R radio observatory in 2011. Spektr-R stopped responding to commands from the ground in January after exceeding its planned five-year mission lifetime, and Russian officials declared the mission over in April.

Spektr-RG’s planned mission is set for seven years.

The leaders in the 2019 launch race:

9 China
8 SpaceX
8 Russia
5 Europe (Arianespace)

The U.S. continues to lead China in the national rankings 14 to 9.

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