Year: 2018

Trace Gas Orbiter finds no methane on Mars

11:31 am

The uncertainty of science: Europe’s Trace Gas Orbiter (TGO) has failed to detect any methane in Mars’ atmosphere, even though data from Mars Express in 2004 had said it should see some.

The Mars Express orbiter first detected hints of methane in the martian atmosphere in 2004. But some scientists said the orbiter’s instruments that found it—at a level of 10 parts per billion (ppb)—weren’t sensitive enough to produce reliable results. Ten years later, NASA’s Curiosity rover detected a methane spike of 7 ppb from its base in Gale crater, which lasted several months. Several years later, Curiosity’s scientists then discovered a minute seasonal cycle, with methane levels peaking at 0.7 ppb in the late northern summer.

To settle this mystery, the European Space Agency’s Trace Gas Orbiter (TGO), which arrived at Mars in 2016, this year began to scan the atmosphere for methane. Two of the TGO’s spectrometers—a Belgian instrument called NOMAD and a Russian one called ACS—were designed to detect methane in such low concentrations that researchers were sure they would. Both instruments, which analyze horizontal slices of the martian atmosphere backlit by the sun, are working well, scientists on the team said today at a semiannual meeting of the American Geophysical Union in Washington, D.C. There’s still some noise to clean up, said Ann Carine Vandaele, NOMAD’s principal investigator and a planetary scientist at the Royal Belgian Institute for Space Aeronomy in Brussels, in her talk. “But we already know we can’t see any methane.”

The team’s initial results show no detection of methane down to a minute level of 50 parts per trillion, with their observations going down nearly all the way to the martian surface.

The data says that any methane seen on the surface (such as by Curiosity) must be coming from below, not from off world, which in itself is a surprise since the scientists expected some methane to be coming from interplanetary dust. TGO has found none..

There are a lot of uncertainties still, so stay tuned.

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Why ULA picked Blue Origin’s engine over Aerojet Rocketdyne

11:22 am

In an interview of ULA’s CEO Tory Bruno by Eric Berger of Ars Technica, he subtly revealed why his company in the end favored Blue Origin’s BE-4 rocket engine over Aerojet Rocketdyne’s AR-1 in the design of the Vulcan rocket.

Unlike many of the new entrants that you talk about coming in today, we’re not a startup company living off investor capital; we’re a mature business. We have to close a business case on Vulcan itself. So where our strategic partners [Editor’s note: This is a reference to Blue Origin] brought investment as well as schedule, that was a pretty important factor. It became pretty obvious what the right choice was, and we arrived at it with our stakeholders.

In other words, Blue Origin’s willingness to invest its own capital in engine development was a major factor. Aerojet Rocketdyne was using the old model of big space, whereby all development money came from the government. It had been unwilling to commit any of its own funds to engine development. This reluctance implied it wasn’t really committed to the project. If Air Force funding disappeared, they’d back out, leaving ULA in the lurch.

This tidbit from Bruno also suggests that he and the management at ULA are sincerely working to reshape ULA from an old big space company, totally reliant on the subsidies given by the government, into a modern competitive company focused instead on building an affordable product that customers will want to buy.

This story also tells us a lot about Aerojet Rocketdyne’s future, or lack thereof. The rocket industry is changing, and if that company doesn’t change also, it will soon die.

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Cats might be larger now than in the past

10:44 am

The uncertainty of science: A careful analysis of cat bones from numerous Viking archeology sites going back 2000 years suggests that the size of cats increased during those centuries.

After carefully measuring the bones with an electronic caliper, Bitz-Thorsen and Gotfredsen compared them with those of modern Danish cats dating from 1870 to the present. On average, domesticated cats grew by about 16% between the Viking Age and today, they report this month in the Danish Journal of Archaeology.

The study only focused on Danish cats, so the findings may not be generalizable to other parts of the world. However, a 1987 study of a collection of cat bones from Germany bolsters the idea that domestic cats of the medieval age were smaller than modern-day pets.

They think the size increase was due to better food.

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Virgin Galactic finally reaches space, by one definition

10:36 am

Capitalism in space: By one of the definitions of where space begins, Virgin Galactic’s second SpaceShipTwo Unity finally reached space for the first time during a test flight today.

During a flight test today, Virgin Galactic’s SpaceShipTwo burned its engine for 60 seconds and reached an altitude of 271,268 (51.37 miles/82.7 km), which put the vehicle into space for the first time according to one definition of the boundary.

Pilots C.J. Sturkow and Mark Stucky deployed the spacecraft’s feather system — twin tail booms that re-configure the ship for re-entry — after reaching a top speed of Mach 2.9. They glided the vehicle back to a safe landing on Runway 12-30 at the Mojave Air and Space Port in California’s High Desert.

The U.S military initially defined space as beginning at 50 miles altitude. Later the international definition defining space as beginning at 100 kilometers (about 62 miles) became more accepted. In recent years there has been a push to accept the U.S. military’s older definition (partly I think generated by Virgin Galactic itself). Truth is, the U.S. military’s definition actually makes more sense, since it is possible to orbit a satellite at 50 miles, for short periods.

The pressure to change however does suggest that Unity might not be capable of reaching 62 miles.

Regardless, this flight culminates fourteen years of effort at Richard Branson s company to produce a reusable suborbital spaceship that can fly in space. It appears they have finally done it. Whether it will be reliable enough to fly repeatedly, with commercial passengers, remains to be seen. Moreover, the commercial landscape has changed considerably during those fourteen years. Had they flown a decade ago, as Branson repeatedly predicted, they would have been the only game in town. That is no longer the case. They now have a competitor, Blue Origin with its suborbital New Shepard spaceship, and affordable commercial orbital flights are just around the corner.

Still, Virgin Galactic’s achievement here is significant. They have built a spaceship that has taken humans to space (and can do it again), and they have done it with private funds.

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Do tornadoes form top-down or down-up?

10:13 am

The uncertainty of science: New data now suggests that tornadoes might form from the ground upward, not from the clouds downward, as previously and generally accepted believed.

Houser and a team of researchers from the University of Oklahoma happened to be monitoring the storm with a new type of mobile Doppler radar system that collected tornado wind speeds every 30 seconds. Afterwards, Anton Seimon, a geographer at Appalachian State University in Boone, North Carolina who had chased the El Reno storm, collected hundreds of still photos and videos of the epic twister from citizens and fellow storm chasers.

When Houser compared her radar data with images collected by Seimon, she noticed something odd. The images clearly showed a visible tornado at the ground several minutes before her radar picked it up. Puzzled, Houser went back through her radar data and analyzed the data taken at the ground. It is typically difficult to get good radar measurements at or near the ground, but Houser and her team had deployed their instrument on a slight rise and there were no obstructions between them and the tornado, so this time, they had data good enough to work with.

She found clear evidence of rotation at the ground before there was rotation at higher altitudes. Houser then examined other sets of tornado data and found that in many cases, tornado-strength rotation develops at or near the ground first, rather than starting in the cloud itself. In all four datasets she analyzed, none of the tornadoes formed following the classical “top-down” process.

What is really interesting about this research is that it shows that at least some tornadoes develop from the ground up, something no one predicted. The research also illustrates that the formation of tornadoes is very complicated and that we still do not understand it, in the slightest.

While the researchers here try to imply that this data also proves that all tornadoes must form from the ground up, they are wrong. The data shows that some appear to form from the bottom up, but this does not prove that others might do the opposite. We simply do not know enough yet.

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Syria wants its own space program

10:30 am

The new colonial movement: The head of Syria’s ministry of communications and technology said during a visit to that country’s satellite remote sensing facility that their nation should organize a space program, beginning with the construction of an entirely home-built satellite.

I’m not sure how much of this will be possible considering how badly ripped apart Syria presently is because of its civil war. To me, it looks more like a some somewhat ignorant brasshat, while visiting a space facility, sounding off with what he would like done.

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R.I.P. Riccardo Giacconi

10:13 am

The astronomy community is mourning the passing of Riccardo Giacconi, a pioneer in space X-ray astronomy as well as the first director of the Space Telescope Science Institute, which operates Hubble.

What made him an especially interesting man is that he initially strongly opposed Hubble, preferring the money be spent on X-ray space telescopes. When, during the writing of The Universe in a Mirror, I asked him what prompted his change of opinion that made him head of Hubble, he explained that he felt he “wasn’t being used.” The money for X-ray astronomy just wasn’t there, and rather than chase rainbows he decided to hitch his wagon to something that was certain to produce new science.

The irony is that it was Hubble’s success that probably helped generate the funding for later X-ray space telescopes, such as Chandra.,

Giacconi was a unique and brilliant man. His early X-ray instruments were built by a private commercial company he ran, not a university or NASA. In a sense he was following the classic and older American model here that was abandoned in the 1970s, and is only now beginning to see a resurgence.

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A detailed look at Chang’e-4

9:58 am

Link here. Lots of nice information, including the fact that Chang’e-3 seems to still be functioning in a limited manner, and that Chang’e-4 is depending not on solar panels but a radioactive thermal electric system, similar I think to the RPGs that NASA uses on its deep space missions. (I am uncertain however about this, based on looking at the video at the link, which seems to show solar panels on Chang’e-4. They could be instead panels to protect the spacecraft from the sun’s heat.)

They enter lunar orbit on December 12, and will likely land in the first week of January.

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Russian astronauts complete spacewalk to inspect drill hole

9:30 am

Two Russian astronauts yesterday successfully completed a difficult spacewalk aimed at inspecting the drill hole that had been found on the Soyuz capsule on ISS.

Around midnight in Moscow (4 p.m. EST), the cosmonauts began cleaning the work place to prepare tackling the micro-meteoroid shielding, which turned out to be easier than work with soft insulation. In around 10 minutes, they cut and peeled off a segment of the shielding, but it took them a few minutes to actually see the hole at the edge of the exposed area and they had to cut a second smaller piece of meteoroid shielding.

They improvised an attempt to pick black material extruding from the hole with forceps, but it was very difficult to do in bulky spacesuit and due to the brittle nature of the material. Around six hours into the spacewalk, they finally proceeded with a pre-planned sampling operation.

The spacewalk was so hard because they were working on the outside of the Soyuz capsule in an area where no spacewalk was ever planned. No handholds. They had to bring them with them, and attach them.

No word yet on any conclusions about the drill hole.

Posted from Buffalo, NY. I am finally back from Israel, only to end up in a very cold and snowy place, not my favorite environments. No matter. There is a lecture for me to give tonight.

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