November 1, 2013
November 5 update: India has launched the Mars Orbiter Mission. The spacecraft is now in its planned Earth orbit, and will depart for Mars on December 1.
In more than half a century of trying, only two space agencies — from the United States and Europe — have managed to pull off entirely successful Mars missions. Attempts by Russia, Japan, England, and China to send spacecraft to the Red Planet have all ended in total or near-total failure.
Now India’s space agency, ISRO, hopes to succeed where others have stumbled. Next Tuesday, an Indian PSLV rocket is scheduled to lift off from the Satish Dhawan Space Centre near the country’s southern tip, carrying the Mars Orbiter Mission spacecraft, also known unofficially as Mangalyaan — Hindi for “Mars craft.”
It’s a bold step for India, but then so was its Chandrayaan-1 lunar orbiter, which mapped the moon’s surface in 2008. By designing the $70 million (cheap for a Mars orbiter) MOM mission as a technology demonstrator, the Indian Space Research Organization (ISRO) has taken the cautious route, and may have improved its odds. Rather than load up a big spacecraft with lots of expensive instruments (which would have required a bigger but more failure-prone rocket called the GSLV), ISRO went with the smaller, more reliable PSLV, and a modest payload.
Mangalyaan carries just five small instruments: a color camera, an infrared spectrometer for mapping minerals on the Martian surface, a photometer for measuring hydrogen and deuterium in the atmosphere, another spectrometer focused on the upper atmosphere, and an instrument for measuring methane. The last is of special interest to scientists trying to solve the mystery of methane on Mars. Telescopes on Earth and Europe’s Mars Express spacecraft in Martian orbit have detected enough of the gas in the atmosphere to suggest that it’s being produced currently by Martian organisms. But the Curiosity rover came up empty when it sniffed for methane near the surface. The Methane Sensor for Mars on Mangalyaan is designed to detect atmospheric methane down to several parts per billion. “That would be a valuable contribution,” says Michael Mumma of NASA’s Goddard Space Flight Center, one of the leaders in studying Martian methane. “However, the technical difficulties [of achieving that sensitivity] should not be overlooked.”
We’ll keep our fingers crossed on that one.
If the spacecraft just arrives safely in Mars orbit and operates there for six to ten months as anticipated, that alone could qualify the mission as a triumph. Chandrayaan-1 was rightly seen as a success, but the mission was cut short by component failures, and operating at Mars is more difficult than orbiting the moon. The rocket engine designed to brake Mangalyaan into Mars orbit when it arrives next September will have to start flawlessly after a 300-day cruise through cold space. Communications, power, and thermal control will all be more complicated than they were with Chandrayaan.
The graveyard of lost Mars missions includes 19 from Russia alone (although, to be fair, half of those were early in the space age). Japan’s Nozomi spacecraft suffered a fuel valve problem in 1998, and never recovered enough to reach Mars orbit. China’s small Yinghuo-1 Mars orbiter had hoped to piggyback on the Russian Fobos-Grunt Mars mission in 2011, but both spacecraft were stranded in Earth orbit when a rocket misfired. England’s Beagle 2 lander, launched in 2003, crashed on the Martian surface. NASA has had its failures, too, including the Mars Climate Orbiter lost in 1999 due to a mixup over metric vs. imperial measurements.
So wish the team at ISRO luck. Launch is scheduled for 4:08 a.m. Eastern (U.S.) time on November 5.
Here K. Radhakrishnan, head of the ISRO, gives a lengthy guided tour of the spacecraft for New Delhi Television:
October 30, 2013
Scientists following up on data from the Kepler planet-hunting telescope have identified Earth’s closest twin yet—at least in terms of size and mass. Measuring only 1.2 times the radius of Earth, Kepler -78b is now the smallest planet for which we also know the mass: about 1.7 times Earth’s. The two planets have roughly the same density, which means Kepler-78b is probably made of rock and iron too.
That’s pretty much where the similarity ends, though. Kepler-78b orbits perilously close to its host star—so close, in fact, that its year lasts only 8.5 hours, and surface temperatures are several thousand degrees on the side facing the star. No water, no life, and no good explanation—at least not yet—for how such a small planet ended up so close to its star. According to current theory, the star would have been two to three times bigger than it is today when the planet formed. But if -78b started off in its current location, “the planet’s orbit would be inside the star itself,” which is clearly not possible, says Dimitar Sasselov of the Harvard-Smithsonian Center for Astrophysics in Boston, speaking at a press conference today. One possible explanation is that the planet is the dead core of a gas giant planet that migrated inward from farther away, but that theory is problematic too, says Sasselov. He called -78b “a poster child for a totally new class of planets” that has recently emerged from the Kepler data.
The discovery sets a new standard for observing small, rocky worlds. Kepler found the planet and measured its radius last spring, but it wasn’t until the summer that two independent groups—one working with the HIRES spectrograph at the Keck Telescope in Hawaii and the other with the HARPS-N spectrograph at Italy’s Telescopio Nazionale Galileo in the Canary Islands—were able to make the exquisitely sensitive measurements that allowed them to calculate the mass of Kepler-78b, based on the spectral signature of the tiny planet tugging on the much bigger star.
The two teams reported their results in Nature magazine today.
October 29, 2013
Harriet Baskas likes going to small museums that don’t get many visitors—collections of lightbulbs, hoards of Barbie dolls, piles of nuts. In these kinds of places, Baskas writes in her new book Hidden Treasures, “the volunteer on duty is apt to follow you around.” She often asks her minders to point out their favorite items. Sometimes, the best stuff isn’t on display; perhaps the artifact is too valuable, or extremely fragile. Or maybe it’s not on view because it is too politically or culturally sensitive.
Baskas uncovered many of these hidden treasures for a 26-part NPR radio project, which she’s now turned into a book. Of course we had to find out if she included anything aviation-related. And she did!
First up: Katharine Wright’s knickers. As Baskas writes, “Katharine was sometimes referred to as the ‘third Wright Brother,’ yet her life story and her role in the birth and growth of aviation has been generally overlooked. The collection at the International Women’s Air & Space Museum in Cleveland, Ohio, includes a dress that Katharine wore to the White House in 1909 when her brothers received the Aero Club of America award, as well as a pair of knickers. Only the dress is on display. “If we were an Edwardian museum or a fashion museum, the knickers [would] be used in an exhibit,” collections manager Cris Takacs is quoted as saying. “We have not displayed them, in part because there are still some members of the Wright family around.”
Next: Neil Armstrong’s spacesuit. The Apollo suits, says Baskas, were designed “to withstand temperatures of plus or minus 150 degrees Fahrenheit, radiation, and the possible penetration of particles traveling up to 18,000 miles an hour.” But they weren’t meant to last more than six months. Neil Armstrong’s spacesuit was displayed at the National Air and Space Museum almost continuously from 1973 to 2001, she writes, but was removed due to concerns about damage from humidity and light. It now lives in a cold vault at the Steven F. Udvar-Hazy Center in northern Virginia.
Third on our list: The metal detector that screened terrorists at the Portland, Maine, airport on the morning of September 11, 2001.
The detector is now in the Transportation Security Administration (TSA) headquarters building in Washington, D.C., and isn’t meant to be part of a public tour. “TSA historian Michael Smith says that’s partly because his department has only two staff people,” Baskas writes, “but it’s mostly because the main goal of the project is to share the history of the agency with the TSA workforce, which now includes more than 50,000 people at more than 400 airports across the country. ‘A lot of people…they were just teenagers when it happened,’ says Smith. ‘So it’s important to tell that story to all of our employees.’”
At the time of the 9/11 attacks, Baskas writes, all of the screening equipment was owned by the airlines. “Delta Air Lines owned the Rapiscan machine the terrorists walked through in Portland, and after 9/11 the FAA pulled that machine off the line.” Eventually Delta put the machine in storage, where it remained until 2005, when the airline donated it to the TSA.
Last on our list is Colton Harris-Moore’s—aka the “Barefoot Bandit”—pilot’s operating handbook. Baskas notes that Harris-Moore became famous during “a multiyear crime spree that stretched from Washington state’s San Juan islands to Canada and the Bahamas and included dozens of burglaries and break-ins and the theft of cars, boats, bikes, and planes.” Harris-Moore was sentenced to seven years in state prison. In November 2012, the local sheriff’s office on Orcas Island called the Historical Museum and asked if they’d like multiple boxes of evidence from the trial. Included in the boxes were the pilot’s flight manuals that Harris-Moore used. The museum asked for input from the community on whether the items should be put on display, Baskas notes, as many of the locals were victims of Harris-Moore. Eirena Birkenfeld, the museum’s former community outreach coordinator, told Baskas “On the one hand is the fact that Colton Harris-Moore is now part of Orcas Island history. His presence dominated the island for many months. On the other side is the feeling that we shouldn’t be giving him any more notoriety.”
October 24, 2013
Many of the space missions we send to Mars and other planets search for evidence of life. Or rather, they search for life as we know it — life that’s made of carbon, requires liquid water, and uses light or chemical energy as its main energy source. Sara Seager and her colleagues from MIT, William Bains and Renyu Hu, want to expand this “earth-centric” approach. They suggest looking for any gas that is out of equilibrium as a possible signature of life on exoplanets. (We say “possible” because geological processes, particularly volcanic eruptions, can also affect the equilibrium.)
On Earth, the out-of-equilibrium gases oxygen and methane are a biosignature. If they were not constantly replenished by life processes (plants that produce oxygen and bacteria that produce methane) the two gases would react to produce the relative inert gas carbon dioxide.
Seager and her colleagues built a model that predicts how elements might combine naturally in the atmospheres of other planets. By comparing the model to actual observations of exoplanet atmospheres, the presence of life might be revealed. For example, for planets with atmospheres dominated by hydrogen, the model predicts that methyl chloride, dimethyl sulfide and nitrous oxide could indicate the presence of life. Researchers are hoping that the James Webb Telescope, due to launch in 2018, will be able to detect biosignatures such as these.
Speculations about weird life on other planets have always been popular among scientists and science fiction readers. It would be extremely “earth-centric” to presume that the biochemistry on our planet is the only way life can operate. But just how different can it be? One extreme example are the “Horta,” the silicon-based life portrayed in Star Trek. Could we expect organisms like that on a terrestrial, meaning Earth-type, planet? Most likely not, because the biochemistry of life is intrinsically related to its environment. On Earth, silicon and oxygen are the main building blocks of Earth’s crust and mantle. Most rocks, particularly volcanic and igneous rocks, are built from silicate minerals, which are based on a silicon and oxygen framework. Any free silicon would be bound in these rocks, which are inert at moderate temperatures. Only at very high temperatures does the framework become more plastic and reactive, which led Gerald Feinberg and Robert Shapiro to suggest the possible existence of lavobes and magmobes that could live in molten silicate rocks. Yet no one has ever discovered any traces of extinct life or fossils in a granite or basalt, suggesting that carbon, with its matching solvent, water, simply works so much better than silicon as a building block for life on an Earth-type planet.
But not all is lost for the possibility of silicon-based life. On an extreme world like Titan, there is no oxygen in the atmosphere and all water is frozen solid, so silicon is not oxidized right away into inert rock. Further, Titan has liquid methane and ethane on its surface, and methane would be a good solvent for silicon. Silicon molecules such as silanes (SiH4) and polysilanes (compounds with multiple SiH4 groups) mimic organic chemistry on Earth. They would be stable and could be the start of an alien biochemistry.
Should we expect silicon-life on Titan, then? Probably not — unfortunately, there is too much carbon around to react with other compounds abundant in the Titan environment, and too little silicon, most of which is locked up in the deep interior. Still, if there is life on Titan, silicon may be used more as a building material than it is for life on Earth. Even on our own planet, the common algae known as diatoms require silicon for growth, and silicic acid is found in hair, nails, and the epidermis. Life is often much more inventive than we think.
Dirk Schulze-Makuch is a professor of astrobiology at Washington State University and has published seven books related to the field of astrobiology. He is also adjunct professor at the Beyond Center at Arizona State University.
October 23, 2013
Suddenly, the “edge of space” is a hot destination.
No sooner had a documentary on Felix Baumgartner’s 24-mile-high leap last year come out (you can watch on the web) when a Tucson-based startup, World View, announced plans to take tourists up to the stratosphere starting in 2015. No jumping, though — just sightseeing, from a pressurized capsule hanging from a balloon. Ticket price: $75,000.
The plan, according to a letter from the FAA to Paragon Space Development Corp., the company behind the venture, is for a capsule carrying eight passengers to ascend from Spaceport America in New Mexico. Once they reach an altitude of 18.6 miles, high enough to see black sky and the curvature of Earth, the tourists will float there for two to six hours. The World View video shows lots of big windows for looking out.
In its communication with the FAA, Paragon called its passenger vehicle a “space capsule,” and generally seems keen to use the term “space” in describing the project. Purists might argue. Bear in mind that the balloon will reach less than one-tenth the altitude of the space station. But the experiences we generally lump together as “space tourism” are starting to come in different flavors, each with its pros and cons. For roughly the same price — $95,000 — you can book a ride on the Lynx spaceplane, which will go much higher (200 miles), but on a ride that lasts minutes instead of hours.
Meanwhile, the Perlan Project hopes to crowd-fund their idea to fly scientists up to the stratosphere in gliders to do research. They must be tired of watching their balloon-borne instruments have all the fun.
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