- Water on Ceres
- Rosetta Wakes Up
- Venus: Old Data, New Analysis
(From Tom Ruen, Eugene Antoniadi, Lowell Hess, Roy A. Gallant, HST; via NASA; used w/o permission.)
We knew that Mars had an atmosphere, but not much water, when I was in high school. It was remotely possible that plants of some sort lived there, since astronomers has seen dark areas change shape and color with Martian seasons. Some thought Venus might support life, too, but we knew even less about that planet.
In November of 1964 Mariner 4 sent back photos of Mars. It looked a lot like the moon. No canals, no Barsoomian cities. Just craters.
(From NASA, used w/o permission.)
About two years earlier, Mariner 2 had gone past Venus. Scans showed that the planet was hot: about 900° Fahrenheit.
We kept sending robotic explorers to these planets anyway.
Mars almost certainly never produced Percival Lowell's imagined civilization, but we've found ice just under the surface, what's left of rivers, and — maybe — an ancient seabed. Venus may have water, too: locked deep in the planet's mantle.
Joshua 10:12-13 too, but my faith isn't dependent on pre-Copernican cosmology.1
As a Catholic, I'm expected to read the Bible. But I don't consult Sacred Scripture when my computer acts up: and that's another topic. (January 14, 2011)
Being curious about this wonder-filled universe is okay. So is using what we've learned to help each other. (Catechism of the Catholic Church, 2292-2296)
But no matter how curious we are, or how much we want to help someone, we're not allowed to help one person by hurting another. That's where ethics comes in. (Catechism, 1753)
(image courtesy NASA/JPL-Caltech)
Genesis 1:28 outlines part of our job description:
"God blessed them, saying: 'Be fertile and multiply; fill the earth and subdue it. Have dominion over the fish of the sea, the birds of the air, and all the living things that move on the earth.' "We don't own the universe. It's not ours to rip apart if we like. We're stewards, given the responsibility of maintaining and developing resources for each other, and for future generations. (Catechism, 2415-2418)
Thanks in part to appalling mistakes made at the industrial revolution's height, fashionable belief in Progress with a capital "P" has been replaced with fashionable antipathy toward science and technology. Both are silly, in my considered opinion.
Cleaning up the mess left by folks in the 19th and early 20th centuries will take generations: but the problem wasn't science and technology. It was short-sighted, greedy use of these tools.
We can do better, and are learning to do so.
More of my take on science, technology, and stewardship:
- "Love, Technology, and Being Human"
(October 6, 2013)
- "Tracing the Y Chromosome, Studying Fossil Proteins, Seeking Truth"
(August 16, 2013)
- "Designed as Stewards"
(March 17, 2013)
- " '...The Man With the X-Ray Eyes," the Tuskegee Experiment, and Seeking God'
(February 10, 2013)
(From IMCCE-Observatoire de Paris/CNRS/Y.Gominet, B. Carry; via Space.com; used w/o permission.)
"An artist's impression of water outgassing from two sources on the dwarf planet Ceres, which is also the largest asteroid in the solar system."
"Water Found on Dwarf Planet Ceres, May Erupt from Ice Volcanoes"Ceres was an asteroid in my youth, now it's a dwarf planet. Ceres didn't change: we've learned more about the Solar system, relabeling some places in the process.
Tanya Lewis, Space.com (January 22, 2014)
"Astronomers have discovered direct evidence of water on the dwarf planet Ceres in the form of vapor plumes erupting into space, possibly from volcano-like ice geysers on its surface.
"Using European Space Agency's Herschel Space Observatory, scientists detected water vapor escaping from two regions on Ceres, a dwarf planet that is also the largest asteroid in the solar system. The water is likely erupting from icy volcanoes or sublimation of ice into clouds of vapor.
" 'This is the first clear-cut detection of water on Ceres and in the asteroid belt in general,' said Michael Küppers of the European Space Agency, Villanueva de la Cañada, Spain, leader of the study detailed today (Jan. 22) in the journal Nature...."
The ESA's discovery isn't a surprise, it's a welcome confirmation that there's water in Ceres: possibly chemically bonded to its soil or rocks, maybe as a subterranean ocean. (Apathetic Lemming of the North (March 5, 2009))
Maybe that should be subcererian ocean. I still feel odd, writing about geology of Mars, and that's yet another topic.
Finding water on Ceres is important, at least for folks studying how the dwarf planet formed. Küppers says that water on Ceres supports the idea that the orbit of planets changed quite a bit in the early Solar system. It also may explain why Ceres and Vesta are so different.
Water vapor transports heat quite effectively. Water boiling off Ceres may have cooled that dwarf planet down so rapidly that it didn't have time to lose its water and end up like Vesta. Make that water sublimating off Ceres.
Right now, finding water on Ceres is close to being pure science: an answer to a question which expands the archive of humanity's knowledge, but is of little practical value.
A few decades from now, water in Ceres might make the dwarf planet economically important, as coal made south Wales important from around 1800 to the late 1900s.
Not that I think we'll have a 22nd century water miners' strike.
(From ESA, used w/o permission.)
"Team cheering at ESOC after successful signal is received from Rosetta."
"Rosetta comet-chaser phones home"Maybe "will occur in November" means "is expected to occur in November" in British English. I'm sure that ESA is doing a good job, and hope that Philae lands in November of this year. But accidents happen.
Jonathan Amos, BBC News (January 20, 2014)
"Rosetta, Europe's comet-chasing spacecraft, has woken from its slumber.
"A signal confirming its alert status was received by controllers in Darmstadt, Germany, at 18:17 GMT. Rosetta has spent the past 31 months in hibernation to conserve power as it arced beyond the orbit of Jupiter on a path that should take it to Comet 67P/Churyumov-Gerasimenko in August.
"Engineers will now finesse the probe's trajectory and prepare its instruments for the daring encounter.
"One of the highlights of the mission will be the attempt to put a small robotic lander, Philae, on the surface of the 4.5km-wide comet. This will occur in November...."
Comets don't have the reputation for failed missions that Mars does: but we haven't sent as many robots to comets. The score so far: Mars, 21 successful missions out of 51 attempts; comets, 14 successful from 19 attempts.
(From BBC News, used w/o permission.)
Rosetta is headed for 67P/Churyumov-Gerasimenko, a comet that crossed the orbit of Jupiter recently and is headed inwards.
The comet's orbit changed in 1959 when Jupiter and the comet came close enough for 67P/Churyumov-Gerasimenko to get pulled into its current path.
It's the sort of gravity assist used by Voyager spacecraft, in reverse. Someone worked out the math around 1918. We didn't have spaceships then, and that's still another topic.
Rosetta's lander will use its Alpha Proton X-ray Spectrometer and other instruments to analyze 67P/Churyumov-Gerasimenko's surface. Other sensors in the orbiter will map and scan the comet: assuming that all goes well.
We've learned that material in at least some comets formed in water, which couldn't have happened if the "dirty snowball" theories were correct. As I've said before, it's nice when research confirms a theory or hypothesis: and exciting when it doesn't.
I don't think we'll see a space age replay of the big gold rushes, with oxygen taking the place of gold: but volatile substances will be very valuable.
Our robotic spacecraft get along without air, food, and water. We can't.
Lunar expeditions, or near-earth-orbit installations like the International Space Station, carry supplies or rely on regular cargo runs from Earth. That won't work as we move farther out.
Living off the land, or ISRU as NASA calls it, may be the only practical option for explorers. For settlers, it's the only option, period. I'll get back to that.
More about comets and ESA's Rosetta mission:
- Rosetta (ESA)
- Fact Sheet
- "Rosetta, ESA's 'sleeping beauty' wakes up from deep space hibernation"
ESA (January 20, 2014)
discovery of minerals requiring liquid water for their formation
challenges the paradigm of comets as 'dirty snowballs' frozen in time."
University of Arizona; via News & Events, Solar System Exploration, NASA (April 7, 2011)
- "Giotto (spacecraft)"
- "Rosetta (spacecraft)"
(From USSR/NASA National Space Science Data Center, via LiveScience, used w/o permission.)
"Thirty-year-old Data Offers New View Of Venus"The Soviet Union launched a half-dozen missions to Venus between 1981 and 1984. Three were particularly successful.
Jessica Orwig, ISNS, via LiveScience (January 18, 2014)
"In 2010, the European Space Agency’s Venus Express orbiter observed that twice as many hydrogen atoms as oxygen atoms were escaping from Venus into space. This was the first evidence that Venus might once have harbored puddles, pools and even lakes of liquid water on its surface. Now, a new study suggests that Venus could be storing some amount of intact water molecules within its mantle.
"To determine this, Justin Filiberto, a geologist at Southern Illinois University in Carbondale, compared what geologists know about the composition of rocks on the surface of Venus with rock formation processes here on Earth. His results, which appeared in the December issue of the journal ICARUS, suggest that some types of rocks on Venus could only have formed in the presence of water and carbon dioxide...."
Venera 13 collected and analyzed soil samples, and sent back a color picture of the Venusian surface. The lander sent back data for 127 minutes before going silent. Venera 14 lasted 57 minutes on the surface. Vega 2's lander lasted 56 minutes.
That's doing pretty well, considering the environment. Air pressure was 94 times Earth's, the temperature nearly 869 87 °F: 465 °C.
Other robot spaceships landed on Venus, including some sent by NASA. BBC Says that Venera 13, 14, and Vega 2 sent back the most comprehensive reports of what's in the soil of Venus.
We do have detailed data about similar rocks on Earth. Filiberto says that Venera 14 and Vega 2 samples contained crystal structures similar to basalts on Earth: the sort formed in the upper mantel, where there's a little water and not as much pressure as deeper in our planet.
Venera 13's landed on a bit of high ground called Phoebe Regio. Samples taken there resemble rocks formed deeper in Earth's mantle, from magma rich in carbon. Occam's Razor suggests that the Venusian rocks formed deep within Venus.
(From NASA Ames Research Center, U.S Geological Survey and Massachusetts Institute of Technology; via Wikimedia Commons; used w/o permission.)
NASA's Pioneer Venus 1 orbiter could "see" the Venusian surface with radar. NASA, Ames Research Center, the USGS, and MIT made the topographic map up there from Pioneer's data.
Under the clouds, Venus looks a little like Earth. There's even a sort of continent near the north pole. We're learning that Venus has 'earthquakes,' and almost certainly volcanic eruptions. There's tectonic activity: but not plate tectonics. That may or may not have something to do with the astonishingly high temperatures and thick atmosphere of Venus.
(From NASA Ames Research Center, U.S Geological Survey and Massachusetts Institute of Technology; via Wikimedia Commons; used w/o permission.)
I made a globe of Venus by wrapping another topographic map around a sphere. Then I decided to have a little fun.
Terraforming, changing another planet's environment into something suitable for our sort of life, is a fairly new word. On the other hand, folks changing the landscape to suit their needs is nothing new. (October 11, 2013)
My guess is that we'll "terraform" other planets a few acres at a time, as needed to support explorers or settlers: probably starting with Mars.
Venus is a much closer match to Earth than Mars: except for temperatures hotter than Mercury's, sulfuric acid rain in the upper atmosphere, and air pressure about 94 times what we're used to. On top of that, a day and a year on Venus take very roughly the same amount of time.
Maybe humanity won't ever get around to terraforming Venus. It would be a huge project.
Even after tapping water locked in the Venusian mantle, converting the atmosphere into something that's non-toxic, and probably speeding the planets rotation up to something like Earth's - - - you get the picture.
If we do decide that making Venus into something resembling the tropical wonderland imagined by artists like Frank R. Paul, it still won't have dinosaurs, munchkin villages, and bipedal amphibious flying squirrels.
Or maybe it will. We've already made glow-in-the dark pigs and cats. I can imagine someone deciding that Venus 2.0 would be more inviting if we stocked it with graceful pterosaurs: or maybe those things are enormous herons.
As long as we don't hurt people in the process, I don't see an ethical problem with terraforming Venus. (October 25, 2013)
Customizing critters for the new environment adds another layer of ethical concerns: but I don't see a problem there, either. Not in the basic idea. (November 22, 2013)
A thousand or so years from now, maybe we'll have the technology and economic need for a terraformed Venus.
It might resemble my second globe: after we've cooled the planet off, converted the carbon dioxide/nitrogen atmosphere to the oxygen/nitrogen mix we use, added prodigious quantities of water, and kick-started ground cover growth near the coastlines. My guess is that the process will take centuries, probably more.
Looking at snow cover on the highest land, I suspect there's going to be a lively debate between folks who want a tropic paradise and winter sports enthusiasts. And that's yet again another topic.
More about Venus:
- "Interactive GIS Map of Venus"
United States Geological Survey
- "The Surface of Venus"
Davison E. Soper, Institute of Theoretical Science, University of Oregon
- "Observations and explorations of Venus"
- "Kepler-69c and Habitable Zones; The Great Martian Land Rush"
(October 25, 2013)
- "Fusion Power, Terraforming, and Old Dutch Windmills"
(October 11, 2013)
- "Robots, a Martian Dune, and Mapping a Billion Stars"
(May 10, 2013)
- "Oceans on Venus; a Very Long Time Ago; Maybe"
Apathetic Lemming of the North (July 15, 2009)
- "Cloud Cities of Venus"
Apathetic Lemming of the North (July 25, 2008)
1 I know the popular version of Galileo Galilei's run-in with the Catholic Church. (October 26, 2009)
I also know that he was a member of the Vatican science academy before his abrasive personality struck sparks on Reformation-era politics.
My native culture's tale of a noble scientist attacked by ignorant papists is only slightly more accurate than that of George Washington tossing a silver dollar across the Potomac. That sort of discrepancy between fact and folklore helped me become a Catholic, and that's — you guessed it — another topic.