2014 was a pretty remarkable year in space news. We saw the long-awaited test flight of NASA's new crewed space capsule, a tragic private spaceflight accident, and the Philae probe make a historic landing on the comet 67P/G-C: the first-ever landing on a comet.
Here's a look back at 2014 in space, in 11 images.
1) The Kepler telescope finds hundreds of distant planets
Prior to 2014, scientists had confirmed the existence of about 1,000 exoplanets (planets that orbit other stars). But in a single announcement in February, scientists announced that using data from the Kepler telescope, they'd found an additional 715 new planets. Soon afterward, in April, astronomers announced that 500 light years away, they'd found a roughly Earth-sized one (illustration above) that might be the right temperature for liquid water.
These planets are mostly too far away for us to learn much more about, but over the next decade, a new generation of telescopes will search for closer planets and allow us to analyze their atmospheres. Some scientists think that within a generation, we may even be able to spot signs of distant alien life.
2) Scientists find gravitational waves. Or wait, maybe not.
In March, a group of astrophysicists announced one of the biggest discoveries in the field in decades: using a telescope at the South Pole, they'd found evidence of gravitational waves in space. These would have confirmed a crucial part of the Big Bang theory — and solidified our understanding of the formation of the universe.
Except, as it turned out, the discovery was probably wrong. Subsequent work has shown that the signal originally detected was likely the effect of dust scattered throughout the galaxy. The debate hasn't been settled yet, but in all likelihood, scientists will have to keep searching for gravitational waves.
3) Tensions between the US and Russia reach the space station
In May, tensions between the US and Russia over the latter's invasion of Crimea threatened to affect the two countries' chief partnership: the International Space Station (ISS). In response to economic sanctions, Russia threatened to stop ferrying NASA astronauts to the ISS beginning in 2020.
Tensions have cooled slightly, and Russia has appeared to back off that threat, but it does expose a huge liability in NASA's crewed space program. After the retirement of the space shuttle, the agency put a plan in the works to hand off transport to the ISS to private companies, but delays have forced NASA to be entirely reliant on Russia for human transport. SpaceX and others are currently delivering cargo to the ISS, but they won't be ready to carry humans until 2017 at the earliest.
4) SpaceX's new Dragon V2 capsule debuts
Just weeks after the Russia news, however, SpaceX debuted its new Dragon V2 capsule — an upgraded version of its current space capsule that's capable of carrying humans.
Later, NASA formally announced that both the Dragon and Boeing's CST-100capsule were selected to go forward in the plan to transport astronauts to the ISS. If all goes as planned, that will begin in 2017.
5) The most detailed map yet of our place in the universe
In September, scientists released a truly awe-inspiring map: one that shows our galaxy's place among hundreds of thousands of others, as part of a giant supercluster of galaxies called Laniakea.
The enormous structure is an estimated 500 million light years across, and is home to more than 100,000 galaxies. Each of these galaxies, meanwhile, contains billions or perhaps even trillions of stars. And our supercluster, the scientists found, borders another, similarly large one called Perseus-Pisces.
6) India's Mars Orbiter Mission reaches Mars
In September, India became the fourth country to successfully put a probe in orbit around Mars. This photo is one of the first it took upon entering orbit.
The craft is mainly a demonstration of technology, though it'll also conduct some analysis of the planet's atmosphere. But the fact that India's fledgling space program succeeded on its first attempted mission to Mars is pretty remarkable — the initial attempts by the US, Russia, and China all ended in failure.
7) Virgin Galactic's SpaceShipTwo crashes over California
In October, Virgin Galactic's SpaceShipTwo — a space plane that the company intends to use to carry tourists into low Earth orbit — crashed during a test flight in California, killing one pilot. The accident came just days after another private spaceflight disaster: the explosion of an uncrewed rocket, owned by the Orbital Sciences Corporation, which was heading to the International Space Station for a cargo resupply mission.
The cause of the Virgin accident still hasn't been fully determined, but it comes after experts had previously criticized the company's cavalier attitude towards safety. Still, Virgin says it will proceed with its plans to carry tourists into space.
8) Philae touches down on the comet 67P/C-G
In November, the European Space Agency's Philae because the first spacecraft ever to land on a comet. The composite panorama, above, shows the photos taken by Philae upon landing.
The landing didn't go exactly as planned — the lander actually took a series of large bounces because its harpoons didn't fire upon landing — but the mission was still a huge success. Data from both Philae and Rosetta (the spacecraft that brought it to the comet and is still orbiting it) have already provided new information about comets, which could help us better understand the formation of the solar system.
9) NASA tests its Orion capsule for the first time
In December, NASA carried out a successful test of its Orion capsule — a spacecraft that it hopes to use to carry astronauts into deep space. Plans are still uncertain, but NASA's stated goal for Orion is to eventually use it to put humans on Mars.
This first test, with an uncrewed capsule, was a success, with the craft making two orbits of the Earth, including one at an altitude of 3,600 miles. This is more than ten times higher up than the International Space Station, and farther away from Earth than any crewable craft has traveled since 1972.
10) Curiosity keeps finding evidence that Mars was once habitable
In 2014, the Curiosity probe's big Mars discoveries kept coming. Most recently, in December, it discovered evidence of an ancient lakebed, as well as organic molecules and mysterious plumes of methane gas. Together, these findings and other data have many scientists convinced that Mars was once warmer and wetter than it is today — and perhaps even home to life.
In 2015, the rover will climb a giant mountain called Mount Sharp, sampling a succession of rock layers that will help us learn more about the planet's geologic and atmospheric history.
11) The space station orbits onward
It may not sound like the most dramatic news. But as Charles Fishman points out in an outstanding new feature in the Atlantic, the International Space Station has now been occupied for nearly 5,200 days since its 2009 completion. We don't pay it much attention, but as he writes, "in the past decade, America has become a truly, permanently spacefaring nation."
The ISS hasn't produced any huge scientific discoveries or technologies — mainly, it's an exercise in figuring out how humans can adapt to living in space. In March, astronaut Scott Kelly will head to the ISS for NASA's first ever year-long mission, twice as long as most astronauts spend in orbit. The surreal sunrise timelapse above, captured by the European Space Agency's Alexander Gerst, shows what astronauts spend much of their time on the ISS staring at: the Earth, spinning swiftly underneath them day and night.