2014’s not quite over yet, but the year has already yielded some amazing scientific insights in space. In honor of the United Nations’ World Space Week, we wanted to round up some of our favorite discoveries and milestones in space exploration and astronomy this year:
This was the year that the European Space Agency’s Rosetta spacecraft finally got to get up close and personal with Comet 67P/Churyumov-Gerasimenko. In August, the craft successfully met up with the comet—a rendezvous 10 years in the making.
Patrick McCarthy, project director for the Giant Magellan Telescope, says the mission is a true step into the unknown. Until now, we haven’t gotten a really good, up close look at a comet: “We usually just see light reflected off of the cloud of dust around it.”
Rosetta’s snapshots of Comet C-G show that it’s irregularly shaped, with two bulbous heads connected by a squat bridge; overall, the comet looks kind of like a rubber duck. In November, Rosetta will attempt to land the Philae probe on the head of that comet duck in order to start directly analyzing the composition and attributes of the comet.
Scientists are excited to get a look at this data because Comet C-G is like a frozen time capsule of material from the nebula our solar system formed out of. Locked inside the comet may be clues to how the solar system formed, and perhaps hints at whether water on Earth was brought to our planet on the backs of similar comets. “It’s our first chance to directly get our hands on that material,” McCarthy says.
As of early October, scientists have confirmed the existence of 1,760 planets outside our solar system. This year, researchers have taken ever-closer looks at some of these alien worlds, with several notable finds this year, including Kepler-186f, the first Earth-sized exoplanet found orbiting in its star’s “habitable zone,” an area where it is possible for liquid water to exist. And in September, astronomers discovered that the Neptune-sized exoplanet HAT-P-11b has water vapor in its atmosphere.
In September, India joined the short list of nations on Earth that have traveled to other worlds in our solar system. The Indian orbiter Mangalyaan, which launched form Earth last November, will be mapping the Martian surface and scrutinizing the Red Planet’s atmosphere.
Researchers claimed to have discovered the oldest star seen by mankind thus far at least twice this year. In February, an Australian-led team detailed the chemical composition of the star SMSS J031300.362670839.3, which seems to be at least 13 billion years old, and may be even older, possibly forming shortly after the Big Bang 13.8 billion years ago.
Then, in late September, a Canadian-US team of scientists released a new study of the star HD 140283, which appears to be 14.3 billion years old. Of course, that probably isn’t its actual age, since that predates the Big Bang; the estimation of this star’s age is based on a careful analysis of the star’s features, but it also includes a margin of error of plus or minus .8 billion years—so an age of 13.5 billion years is just as likely.
The Mars Science Laboratory, better known as Curiosity, touched down on the Red Planet in August 2012 with one primary goal: Get to Mount Sharp, a three-mile-high mountain in the center of a basin formed by an asteroid impact. Over the past two years, Curiosity has already made a number of important discoveries on its way to the mountain. Samples taken from the mudstone flats of the basin suggest that the area was once covered with a freshwater lake, and that all the chemical building blocks necessary to support simple microbial life were present.
In early September, Curiosity reached its destination. At Mount Sharp, Curiosity will be hunting for another sign that Mars could have once supported life: Organic carbon. The rover will also be examining the layers of rock on Mount Sharp to help scientists figure out how Mars’ climate and geology changed over time.
Many theoretical physicists think that the universe underwent a period of rapid swelling right after the Big Bang, called inflation. Researchers think we should be able to see evidence of that rapid expansion stamped into the reverberations from the Big Bang that echo through to today—the cosmic microwave background radiation.
In March, scientists using the BICEP2 telescope at the South Pole said they thought they’d found that signal of inflation: a twisting polarization of light in the CMB that seemed to be evidence of gravitational waves imparted by inflation. There were skeptics of this find from the start, and their hesitance appears to have been vindicated by a new analysis of data from the ESA’s Planck spacecraft, which shows that there’s a strong chance most of, or even all of, the signal BICEP2 found was actually imparted by dust in our galaxy. Further analyses are expected later this year.
“No one expects result to go away entirely, but the confidence level will diminish,” McCarthy says. But the public shouldn’t lose heart in the value of the work the researchers are doing; all of the back-and-forth over the BICEP2 results is all part of the natural give and take of observation and experimentation: “If you never took a risk and put something out there and only waited until everything was perfect, science would go very slowly,” McCarthy says.
Did we miss one of your favorite space discoveries? Let us know in the comments!