Story highlights
- Rosetta is attempting to become first spacecraft to orbit and land on a comet
- European Space Agency's 10-year mission has taken Rosetta billions of miles across solar system
- Scientists hope to learn more about the composition of comets
- The robotic lander Philae is due to touch down in November
After a 10-year chase taking it billions of miles across the solar system, the Rosetta spacecraft made history Wednesday as it became the first probe to rendezvous with a comet on its journey around the sun.
"Thruster burn complete. Rosetta has arrived at comet 67P. We're in orbit!" announced the European Space Agency, which is leading the ambitious project, on Twitter.
Rosetta fired its thrusters on its final approach to Comet 67P/Churyumov-Gerasimenko, known as "Chury" for short, on Wednesday morning. Half an hour after the burn, scientists announced that the craft had entered into the orbit of the streaking comet.
"After 10 years, five months and four days travelling towards our destination, looping around the sun five times, we are delighted to announce finally 'we are here'," said Jean-Jacques Dordain, ESA's Director General, in a statement.
"Europe's Rosetta is now the first spacecraft in history to rendezvous with a comet, a major highlight in exploring our origins. Discoveries can start."
Rosetta probe to explore human origins 04:15
Spacecraft enters comet's orbit 04:05
ESA tweeted a photo of the comet after Rosetta's maneuver. Chury and the space probe now lie some 250 million miles from Earth, about half way between the orbits of Jupiter and Mars, according to ESA.
Could Rosetta unlock Earth's secrets? 02:16
Photos: Rosetta: The comet chaser
Photos: Rosetta: The comet chaser
The Rosetta probe sent an unexpected final image back to Earth shortly before it made a controlled impact onto the surface of Comet 67P last September.
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Photos: Rosetta: The comet chaser
Philae has been found! – The Rosetta spacecraft's high-resolution camera took this image of the Philae lander on September 2, 2016. The lander is wedged into a dark crack on a comet, named 67P/Churyumov--Gerasimenko, hurtling through space. The discovery comes less than a month before the Rosetta mission's end.
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Photos: Rosetta: The comet chaser
Philae is wedged in a dark corner of Rosetta – "We are so happy to have finally imaged Philae, and to see it in such amazing detail," says Cecilia Tubiana of the OSIRIS camera team. She was the first person to see the images when they were downlinked from the Rosetta probe, according to the European Space Agency.
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Photos: Rosetta: The comet chaser
Philae found using images from Rosetta – The image is detailed enough that viewers can pick out features of Philae's 3-foot-wide (1 meter) body. Even two of its three legs can be seen.
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Photos: Rosetta: The comet chaser
One of the primary objectives of the Rosetta mission was to drop the Philae lander onto the comet. The probe was successfully deployed in November 2014, becoming the first probe to land on a comet. But Philae failed to grab onto the comet and bounced around. It fell silent a few days later. Then on June 13, 2015, Philae came out of hibernation and "spoke" to mission managers at the European Space Agency for 85 seconds. This photo above was taken by the lander's mothership, the Rosetta orbiter, after the lander started its descent to the comet.
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Photos: Rosetta: The comet chaser
The Rosetta spacecraft captured this image of a jet of white debris spraying from Comet 67P/Churyumov--Gerasimenko on July 29, 2015. Mission scientists said this was the brightest jet seen to date in the mission. The debris is mostly of ice coated with dark organic material.
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Photos: Rosetta: The comet chaser
This image of Comet 67P/Churyumov-Gerasimenko was taken by Rosetta on July 8, 2015 as the spacecraft and comet headed toward their closest approach to the sun. Rosetta was about 125 miles (201 kilometers) from the comet when it took this image.
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Photos: Rosetta: The comet chaser
Philae wakes up! Mission managers posted this cartoon of the lander yawning after it came out of hibernation on June 13, 2015. They also sent a series of tweets between the lander and its mothership, Rosetta.
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Photos: Rosetta: The comet chaser
Comet 67P/Churyumov-Gerasimenko is a Jupiter-family comet. Its 6.5 year journey around the Sun takes it from just beyond the orbit of Jupiter at its most distant, to between the orbits of Earth and Mars at its closest. The comet hails from the Kuiper Belt, but gravitational perturbations knocked it towards the Sun where interactions with Jupiter's gravity set it on its present-day orbit.
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Photos: Rosetta: The comet chaser
This image of Comet 67P/Churyumov-Gerasimenko was taken by Rosetta on June 5, 2015, while the spacecraft was about 129 miles (208 kilometers) from the comet's center.
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Photos: Rosetta: The comet chaser
Rosetta's navigation camera took this image of the comet on June 1, 2015.
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Photos: Rosetta: The comet chaser
The Rosetta Mission is tracking Comet 67P/Churyumov-Gerasimenko on its orbit around the sun. This image was taken on May 3, 2015 at a distance of about 84 miles (135 km) from the comet's center.
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Photos: Rosetta: The comet chaser
This image of Comet 67P/Churyumov-Gerasimenko was taken on April 15, 2015.
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Photos: Rosetta: The comet chaser
Rosetta snapped this wide-angle view of Comet 67P/Churyumov-Gerasimenko in September 2014. Rosetta was about 107 million miles (172 million kilometers) from Earth and about 92 million miles (148 million kilometers) from the sun when the photo was released.
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Photos: Rosetta: The comet chaser
A camera on Rosetta took this picture of Comet 67P/Churyumov-Gerasimenko on November 22, 2014, from a distance of about 19 miles (31 kilometers). The nucleus is deliberately overexposed to reveal jets of material spewing from the comet. The 2.5-mile-wide (4-kilometer) comet has shown a big increase in the amount of water its releasing, according to NASA. The space agency says about 40 ounces (1.2 liters) of water was being sprayed into space every second at the end of August 2014.
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Photos: Rosetta: The comet chaser
Rosetta took this picture of a section of the comet's two lobes from a distance of about 5 miles (8 kilometers) on October 14, 2014.
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Photos: Rosetta: The comet chaser
The Rosetta spacecraft's Philae lander is shown sitting on Comet 67P/Churyumov-Gerasimenko after becoming the first space probe to land on a comet on November 12, 2014. The probe's harpoons failed to fire, and Philae bounced a few times. The lander was able to send back images and data for 57 hours before losing power.
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Photos: Rosetta: The comet chaser
Rosetta's lander, Philae, wasn't able to get a good grip on the comet after it touched down. This mosaic shows Philae's movements as it bounced across the comet.
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Photos: Rosetta: The comet chaser
Philae snapped these images after landing, and mission scientists used them to create a panoramic view of the landing site. A graphic shows where the probe would be sitting in the photograph.
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Photos: Rosetta: The comet chaser
The image of Comet 67P/Churyumov-Gerasimenko was taken by a camera on the Philae lander during its descent to the comet on November 12, 2014. The lander was about 1.9 miles (3 kilometers) from the surface at the time. Philae touched down on the comet about seven hours later.
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Photos: Rosetta: The comet chaser
Rosetta's OSIRIS camera captured this parting shot of the Philae lander after separation.
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Photos: Rosetta: The comet chaser
Rosetta's lander Philae took this parting shot of its mother ship shortly after separation on November 12, 2014, as Philae headed for a landing on Comet 67P. While Philae is the first probe to land on a comet, Rosetta is the first to rendezvous with a comet and follow it around the sun.
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Photos: Rosetta: The comet chaser
This mosaic is made of four individual images taken about 20 miles (31.8 kilometers ) from the center of the comet on November 4, 2014.
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Photos: Rosetta: The comet chaser
Rosetta took this image of comet 67P/Churyumov-Gerasimenko on September 15, 2014. The box on the right shows where the lander was expected to touch down.
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Photos: Rosetta: The comet chaser
The spacecraft sent this image as it approached the comet on August 6, 2014. From a distance of nearly 81 miles (130 kilometers), it reveals detail of the smooth region on the comet's "body" section.
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Photos: Rosetta: The comet chaser
This image, captured August 7, 2014, shows the diversity of surface structures on the comet's nucleus.
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Photos: Rosetta: The comet chaser
The comet's "head" can be seen in the left of the frame as it casts a shadow over the "body" in this image released August 6, 2014.
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Photos: Rosetta: The comet chaser
This image of the comet was taken on August 1, 2014, as Rosetta closed in its target.
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Photos: Rosetta: The comet chaser
Rosetta's mission started on March 2, 2004, when it was launched on a European Ariane 5 rocket from Kourou, French Guiana.
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Photos: Rosetta: The comet chaser
Rosetta is named after the Rosetta Stone, the black basalt that provided the key to deciphering Egyptian hieroglyphs. Scientists think the mission will give them new clues about the origins of the solar system and life on Earth. The mission is spearheaded by the European Space Agency with key support from NASA.
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Photos: Rosetta: The comet chaser
This photo shows Rosetta being tested before it was wrapped in insulating blankets and loaded on a rocket for launch.
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Photos: Rosetta: The comet chaser
Rosetta has massive solar wings to power the spacecraft. They were unfurled and checked out at the European Space Agency's test facilities before being packed up for liftoff.
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Photos: Rosetta: The comet chaser
After its closest approach to Earth in November 2007, Rosetta captured this image of the planet.
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Photos: Rosetta: The comet chaser
Rosetta snapped this image of Earth in November 2009. The spacecraft was 393,328 miles from Earth.
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Photos: Rosetta: The comet chaser
Rosetta passed asteroid Steins in September 2008, giving scientists amazing close-ups of the asteroid's huge crater. The asteroid is about 3 miles in diameter.
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Photos: Rosetta: The comet chaser
Rosetta took this image of Mars as it looped through the solar system.
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Photos: Rosetta: The comet chaser
This image was taken by an instrument on Rosetta's Philae lander just minutes before the spacecraft made its closest approach to Mars. Part of Rosetta and its solar arrays are visible.
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Photos: Rosetta: The comet chaser
On July 10, 2010, Rosetta flew about 1,864 miles from asteroid Lutetia, which is 10 times larger than asteroid Steins.
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Photos: Rosetta: The comet chaser
Look closely at the top of this picture. See that dot? That's Saturn. Rosetta snapped the picture of asteroid Lutetia and captured Saturn in the background.
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Photos: Rosetta: The comet chaser
After taking pictures of Earth, Mars and asteroids, Rosetta was put into hibernation in May 2011 after it reached the outer part of the solar system. Mission managers woke it January 20, 2014.
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The first spectacular and detailed images taken from just 80 miles away shows boulders, craters and steep cliffs and are already causing excitement.
"Churyumov-Gerasimenko looks like it's been through the wars!" said Dr Robert Massey of the Royal Astronomical Society in the UK.
"With that odd looking 'neck', either we're looking at two objects that merged together or so much material has been lost in its many passes around the sun that the comet is a shadow of what it started out as.
"The pictures coming back so far look intriguing -- and imagine the kind of scenes we can expect when Philae lands this coming November," he said.
To get to its destination the spacecraft has covered more than three billion miles and as the comet hurtles towards the sun it will reach a speed of about 62,000 miles per hour.
The mission has now achieved the first of what it hopes will be a series of historic accomplishments. In November mission controllers aim to place the robotic lander Philae on the surface -- something that has never been done before.
Previous missions have performed comet fly-bys but Rosetta is different. This probe will follow the comet for more than a year, mapping and measuring how it changes as it is blasted by the sun's energy.
Mission controllers had to use the gravity of Earth and Mars to give the probe a slingshot acceleration to meet its target on the right trajectory. Rosetta also had to be put into hibernation for more than two years to conserve power before being woken up successfully in January this year.
Wednesday's thruster burn was the tenth rendezvous maneuver Rosetta has performed since May to get the probe's speed and trajectory to align with the comet's -- and if any of those operations had failed, the mission would have been lost, according to ESA.
For the next few weeks, ESA says the spacecraft will be in a triangular orbit until it gets to about 18 miles of the surface when it starts its close observations.
Scientists hope to learn more about the composition of comets and perhaps whether they brought water to the Earth or even the chemicals that make up the building blocks of life.
"It really is such a step forward to anything that has come before," project scientist Matt Taylor told CNN.
Rosetta will soon begin mapping the surface of and finding out more about its gravitational pull. This will help to find a suitable landing site for Philae and allow engineers to keep Rosetta in the right orbit.
As comets approach the sun, any ice melts and is turned into an ionized gas tail. The dust produces a separate, curving tail. It's these processes that Rosetta scientists hope to be able to study from close proximity.
Taylor explained that the survey will show the team what the comet nucleus looks like now and when it gets closer to the sun.
"We'll be able to make a comparison to now, when its relatively inert, to when it's highly active ... making this measurement over a year when we're riding alongside at walking pace and observing how a comet works and interacts with the sun," he said.
"We are there for over a year to see this complete development to the extent that you may even be able to measure the decrease in the volume of the nucleus ... see how much material has left the comet."
Chury is known as a short-period comet. It reappears every six years as its orbit brings it close to the sun. Halley's comet has a period of about 76 years and is not due to return close enough to Earth to be visible until 2061. Others only return after thousands of years.
Matt Taylor says it is unlikely that you will be able to see comet 67P with the naked eye but you can follow the progress of the mission on Rosetta's blog and find out more with CNN's interactive coverage.
