Science News
Rockets, Life in the Stars, and an Exo-Atmosphere
![55 Cancri e](https://calacademy.org/sites/default/files/styles/manual_crop_standard_960x540/public/assets/screen_shot_2015-05-08_at_3.02.34_pm.png?itok=XDtXcpht&c=27807e616afc313fa6dd0ad8a3c62c91)
Progress Resupply Mission to ISS Spins Out of Orbit
In case you haven’t heard, you can take the hard-hats off. The ill-fated Progress 59 cargo ferry (also known as Progress M-27M), originally destined for the International Space Station, reentered the atmosphere on Thursday night and fell into the Pacific Ocean.
Keeping the space station and its crew of six stocked with supplies takes a steady schedule of cargo deliveries by vehicles that include private spacecraft such as SpaceX’s Dragon or Orbital Sciences’ Cygnus, or more often, Russian Progress ferries—all unmanned. Following the sixth supply run by a Dragon in mid-April, Progress 59 was launched from Baikonur Cosmodrome two weeks later, on April 28. Everything seemed to be going smoothly until ground controllers learned that the Progress vehicle had gone into an uncontrollable spin. All attempts to reestablish contact with the Progress failed, and the mission was declared lost. Speculation as to the cause appeared focused on a staging event—perhaps an explosion—as the ferry detached from the third stage of the Proton launch rocket.
Trapped in a low, unstable orbit, the doomed spacecraft was tracked from the ground and was even sighted by the space station crew, who were never in any danger and could only watch helplessly as three tons of supplies tumbled away. Fortunately, none of the cargo was critical—at least for the American side of the station. Roscosmos, the Russian Federal Space Agency, has not yet revealed whether they lost anything crucial to Russian operations on board the station.
On Friday morning, a terse release from Roscosmos confirmed that the spacecraft had fallen into the ocean. No injuries or damage were reported.
The next supply mission to the space station will be CRS-7, the seventh Dragon resupply flight, currently scheduled for launch on June 19. The next Progress resupply mission is tentatively scheduled for August, followed by a Japanese resupply mission two weeks later. Typically, cargo carriers are allowed to fall to Earth and burn up in the atmosphere. Only SpaceX’s Dragon is designed to survive re-entry and has been used to return cargo to Earth, although so far none have been reused for a second flight. –Bing Quock
“Cosmic Barbeque” part of the origins of life?
Reporting this week in the Astrophysical Journal, a team from the Lawrence Berkeley National Lab (LBNL) and the University of Hawaii at Manoa describe the ideal conditions to form the molecular precursors to DNA—the stuff of life. For decades, astronomers have pointed their telescopes into space to look for nitrogen-containing double carbon rings called quinolone, signatures of these precursors, explains Musahid Ahmed of LBNL. But while stellar environments were deemed likely candidates for the formation of carbon ring structures, no one had spent much time looking there for quinoline.
So the team decided to recreate the conditions near a star at Berkeley’s Advanced Light Source, or ALS. They utilized a device called the “hot nozzle” to simulate the pressures and temperatures in stellar environments of carbon-rich stars. The researchers injected a gas into the hot nozzle, then used the synchrotron radiation from the ALS to probe the hot gas, and saw which molecules formed. They found that the 700-Kelvin nozzle transformed the initial gas into one made of quinoline and isoquinoline, considered the next step up in terms of complexity. Ahmed calls it the “cosmic barbeque.”
They also discovered that the conditions have to be just right for these chemicals to form, which might help when searching for the real thing in space. “There’s an energy barrier for this reaction to take place, and you can exceed that barrier near a star or in our experimental setup,” Ahmed says. “This suggests that we can start looking for these molecules around stars now.” –Molly Michelson
Monitoring Exo-Atmospheres
For the first time, scientists are recording changing conditions of the atmosphere of an exoplanet, and the Super-Earth exoplanet 55 Cancri e is showing us just how different planets of similar size can be.
The planetary system’s Sun-like star, 55 Cancri A, lies a mere 40 light years from Earth, visible in the constellation Cancer. The five planets in the system orbit very close to the parent star, with 55 Cancri e the closest at about 0.015 AU (or 26 times closer than Mercury is to our sun) and completing a full orbit every 18 hours. At about twice our planet’s radius and 7.8 times the mass of Earth, it is considered a “Super Earth” and also happens to be tidally locked with its star, creating a permanent day-side and night-side on the planet. With new data from NASA’s Spitzer Space Telescope, a team has tracked changes the upper atmosphere of the world over the past three years.
“We saw a 300% change in the signal coming from this planet, which is the first time we’ve seen such a huge level of variability in an exoplanet,” says Dr. Brice-Olivier Demory of Cavendish Laboratory, lead author of the new study.
And the potential cause of such extremes?
“We think a likely explanation for this variability is [that] large-scale surface activity, possibly volcanism, on the surface is spewing out massive volumes of gas and dust, which sometimes blanket the thermal emission from the planet, so it is not seen from Earth,” Brice-Olivier continues. If true, that would make 55 Cancri e even more volcanically active than our solar system’s front runner, Jupiter’s moon Io.
The study of 55 Cancri e’s composition has an interesting history. Discovered in 2004, it was initially thought to be a dense wasteland of parched solid rock because it is so close to its star. Spitzer data in 2010 refined estimations of the planet and implied a composition of light elements and compounds—including water—that existed in a superfluid state. Indications that the star, 55 Cancri A, may have a very high carbon to oxygen ratio, even inspired a 2012 paper speculating that, given 55 Cancri e’s density, the planet might be composed mostly of diamond. (In fact, we wrote a Science Today article about it.) However, in late 2013, a team from the University of Arizona revisited the data and showed the star to have lower carbon concentrations than previously thought, dismissing the idea of a diamond planet.
“When we first identified this planet, the measurements supported a carbon-rich model,” says Nikku Madhusudhan of Cambridge’s Institute of Astronomy. “But now we’re finding that those measurements are changing in time. The planet could still be carbon rich, but now we’re not so sure—earlier studies of this planet have even suggested that it could be a water world. The present variability is something we’ve never seen anywhere else, so there’s no robust conventional explanation. But that’s the fun in science—clues can come from unexpected quarters. The present observations open a new chapter in our ability to study the conditions on rocky exoplanets using current and upcoming large telescopes.” –Elise Ricard
The Dragon Flies!
On Wednesday, May 6, SpaceX conducted a Pad Abort Test of the Crew Dragon spacecraft’s emergency abort system, a critical step in certifying the vehicle for launching crews to the International Space Station by April 2017. Powered by eight 3D-printed “SuperDraco” engines, the eight-ton mockup of the human-rated space capsule accelerated from 0 to 100 miles per hour in 1.2 seconds (that’s faster than the infamous “Insane Mode” in a Tesla Model S P85D, which zips from 0 to 60 in 3.1 seconds), expending three tons of fuel in six seconds and reaching a velocity of 345 miles (555 kilometers) per hour. The capsule mock-up was propelled nearly a mile high, where the crew capsule separated from the cylindrical “trunk” section and parachuted gently into the Atlantic surf off Cape Canaveral, Florida, 99 seconds after launch.
A crash-test dummy loaded with sensors was expected to experience nearly five times Earth’s gravitational pull during the boost phase. After the test, SpaceX officials posted that had astronauts been on board during the test, they would’ve been in “great shape.” Following evaluation of test results, the next step in the certification process is to conduct an in-flight abort test of the Crew Dragon mock-up, currently set for no earlier than July and launching from Vandenberg Air Force Base in California.
The last American manned spacecraft to have an emergency escape system was the final Apollo vehicle to fly as part of the Apollo-Soyuz Test Project in 1975. The Soviet-era Soyuz rockets used by the Russian Space Agency have had escape towers from the beginning of the Soyuz program in 1967. –Bing Quock
55 Cancri e Image: NASA/JPL-Caltech/R. Hurt