Tomorrow, January 20, ESA’s Rosetta spacecraft is due to come out of hibernation after over two and a half years. After the wake-up call a series of actions will start with the warming of her star trackers. Rosetta's needs to get oriented and on course for a mission to orbit comet 67P/Churyumov-Gerasimenko and send a lander to it.

Here is an animation from the European Space Agency (ESA) showing what should happen to wake Rosetta up.
How Rosetta wakes up

Hi there Mona - why did they put Rosetta to sleep? Were they waiting for the comet to come 'into view' and in the meantime have Rosetta up there and ready for action? Fascinating how she wakes up ... Very interesting in all! Cheers

Hi Lestie! Much jubilation - and relief - when the signal was received to show Rosetta had woken up. (Hope she's not grumpy.)

And why the hibernation? Rosetta had to get into an orbit that would let her catch comet 67P/Churyumov-Gerasimenko as it swings back in towards the Sun. This put the craft a heck of a long way from the Sun for a few years.

But Rosetta relies completely on solar energy for power - the first mission to do so when traveling so far from the Sun. Although the solar cells were of a new design, nonetheless the available sunlight was way too weak for Rosetta to operate correctly. However there was enough power to maintain the onboard computer and heaters to ensure the craft didn't just freeze up.

ESA has an interactive visualization tool to show where Rosetta has been since launch, or where she is now, or a projection of where she's expected to be. You can see the distance from the Sun, from Earth and from the Comet.

On the page, click on the little "i" to find out how it works. Where is Rosetta?

The climax of an amazing space mission is set for summer 2014. Rosetta, the European Space Agency (ESA) spacecraft, has already traveled for ten years and billions of miles in order to rendezvous with a comet, accompany it as it moves into the inner Solar System, and deploy a lander.

Rosetta the Comet Chaser

Today ESA says: We asked you to help us wake up Rosetta from 31 months of deep-space hibernation in a fun video shout-out contest. With over 200 entries and 75 000 votes, you certainly succeeded! The rules were simple: take out your mobile phone and record a ‘selfie’ of you shouting “Wake up, Rosetta!” But you were far more creative than that…

ESA has made a delightful mashup of some of the fun entries.
Wake up Rosetta

Rosetta has seen Comet 67P/C-G. Here is an image taken last week of Comet 67P with the OSIRIS wide-angle camera. In May the ESA team will need to carry out “a critical series of manoeuvres [to] . . . gradually reduce Rosetta's velocity relative to the comet” for its close encounter at the start of August.

Today the Rosetta team has been carrying out the first of a series of thruster burns. By the end of July there will be another seven of these maneuvers in order to adjust Rosetta's speed with respect to the comet. Otherwise they would just pass by each other.

Rosetta carried out a second course adjustment on May 21st, and will do a third tomorrow. (There will be ten altogether to get the spacecraft to meet the comet in August.) The first thruster burn was small, but the second lasted for 7 hours and 16 minutes. Tomorrow's burn will take 6 hours and 41 minutes. This is slightly less than was originally expected, but it has been adjusted downward using the latest data about the comet's orbit.

Rosetta has been in space for ten years and today, July 9th, she is 20,000 kilometers from Comet 67P/Churyumov–Gerasimenko. That's the same distance as halfway around the Earth at the Equator, so you can see she's getting close, ready for a rendezvous on August 6.

To commemorate Rosetta's impending arrival, ESA is running a photo contest contest celebrating journeys and arrivals. The winner will be invited to ESA's operations center in Germany in November and there are ten runner-up prizes.

Here's a video explaining how to take part in the competition. (It's pretty straightforward.)

Northern hemisphere schools will be out for summer vacation, but others, summer schools, families may be interested in a printable cut-out of Rosetta. Here it is, whether or not you want to enter ESA's contest.

Cut-out Rosetta model

Here is a card to download & print to say where you are going if you want to use in a submission for their competition. And remember the hashtag for social media is #RosettaAreWeThereYet.

There's an entry form on this page and it shows the winners of spot prizes which are already being awarded.

One of the spot prize winners made me laugh.

Here is the picture Rosetta took of Comet C-G on July 29. As you can see, it's an odd shape and has two lobes. This will make the maneuvers needed to get the probe into orbit around the comet very difficult and complex. But after all Rosetta's years in space and all the miles she's traveled to rendezvous with this comet, let's hope that it's successful.

Rosetta is almost there. Yesterday she was closer to the comet than the International Space Station is to the Earth. The final orbital insertion will be happening soon - if successful, Rosetta will be the first space probe to go into orbit around a comet.

Here is a collage of photos which Rosetta has taken over the last few days as she gets ever closer to Comet C-G.

On Wednesday, August 6th, at 4.00 a.m. EDT, Rosetta will, at last, rendezvous with Comet C-G. The European Space Agency (ESA) is going to stream this live. Here is ESA's livestream. You can have a look at it now, before it begins the streaming, to find out more about Rosetta.

The European Space Agency has just reported: We have arrived at the comet! Thruster burn complete.

Rosetta will soon start on her mission to study the comet, which will certainly involve rethinking ideas about comets. You can read more about the history of the Rosetta mission here.

ESA announced yesterday that there were five candidate sites for the Philae lander.

There are all sorts of factors to take into account in order to make the best choice, and there's been only a few weeks to gather information. For example, all five sites seem to meet the requirement of getting enough sunlight to recharge Philae's batteries, but not so much Sun as to cause overheating. But the terrain also has to be suitable for the landing - they will be studying this further.

Here is an ESA infographic about Rosetta and Philae.

ESA has made a cute little video thanking those who took part in their "Rosetta, are we there yet?" photo competition. It shows what part of the world some of the entries came from and the photos themselves.

Did any of them come from where you live?

ESA awarded the top prizes for their photographic competition last week. Here is the winning entry. The prize is attendance at ESA's operations centre in Germany in November, for the VIP event celebrating the first landing on a comet.

Here is the gallery of entries for the competition.

This image, based on high res pictures of Rosetta's comet, looks like a sculpture you might see in an art gallery. However no one has painted the comet, only the image. This is a preliminary map of the comet with different types of terrain shown in different colors. Scientists will soon have to make a decision about where - and how - to land Philae.

"J" marks the spot. ESA has chosen a landing site for Philae, the Rosetta mission's lander. The chosen site is on the "head" of the comet. There's a secondary back-up site on the other site of Comet Churyamov-Gersaimenko.

The Rosetta comet mission has been one of the most demanding and exciting space missions ever. After a 10-year journey to Comet 67P, it's ready to send the lander Philae to the surface on November 12. Here's movie-type preview of the short film that will be coming out soon about the landing. (Credit: ESA / Music: Omega by Tim McMorris)

Judy Schmidt has made an amusing graphic featuring Rosetta's comet Churyumov-Gerasimenko. She compares its size with a number of other objects, e.g., Central Park in New York (which is smaller) and the Martian moon Deimos (which is larger) and the Death Star from Star Wars which would be a LOT bigger, if it existed. Here is Small Bodies.

Ambition: a 6-minute film telling the Rosetta story as a sci fi movie. Great visuals and a good sense of why and how we seek knowledge. Very enjoyable. And, of course, the next installment of Rosetta's story happens live on November 12th when it's time for the Philae lander to meet the comet.

Ambition