News of the Comet-hunting Rosetta mission

[Kenny]

This is awesome. Well worth the investment of 18 minutes quiet time.

http://www.ted.com/talks/fred_jansen_how_to_land_on_a_comet

[Carole]

Thanks for the link Kenny, it was very interesting.

Carole

[Rick]

OSIRIS discovers balancing rock on 67P

Scientists from Rosetta's OSIRIS team have discovered an extraordinary formation on the larger lobe of comet 67P/Churyumov-Gerasimenko in the Aker region. From a group of three boulders the largest one with a diameter of approximately 30 meters stands out: images obtained on 16 September 2014 from a distance of 29 kilometers with the help of Rosetta's scientific imaging system OSIRIS show it to perch on the rim of a small depression. There seems to be only a very small contact area with the nucleus.

Similar geological formations are found also on Earth. So-called balancing rocks touch the underground with only a tiny fraction of their surface and often look as if they may tilt or topple over any moment. Some can actually be rocked back and forth and are then referred to as "rocking stones." Impressive examples of balancing rocks occur in Australia or the southwest of the USA. Often these boulders travelled to their current location onboard of glaciers. In other cases, wind and water eroded softer material surrounding the rock.

More: http://www.mps.mpg.de/3990751/Aktuelles_2015_05_18_OSIRIS_entdeckt_Wackelstein

[ApophisAstros]

A Cliff Looming on Comet 67P

What that looming behind this gravel-strewn hill on Comet Churyumov–Gerasimenko? A jagged cliff. The unusual double-lobed nucleus of Comet 67P/Churyumov–Gerasimenko lends itself to unusual and dramatic vistas, another of which has been captured by the Rosetta spacecraft that arrived at the comet last September.

See today's APOD.

[Rick]

NASA Instrument on Rosetta Makes Comet Atmosphere Discovery

Data collected by NASA's Alice instrument aboard the European Space Agency's Rosetta spacecraft reveal that electrons close to the surface of comet 67P/Churyumov-Gerasimenko -- not photons from the sun, as had been believed -- cause the rapid breakup of water and carbon dioxide molecules spewing from the comet's surface.

"The discovery we're reporting is quite unexpected," said Alan Stern, principal investigator for the Alice instrument at the Southwest Research Institute (SwRI) in Boulder, Colorado. "It shows us the value of going to comets to observe them up close, since this discovery simply could not have been made from Earth or Earth orbit with any existing or planned observatory. And, it is fundamentally transforming our knowledge of comets."

More: http://www.jpl.nasa.gov/news/news.php?feature=4609

[Rick]

The quest to find Philae

While Rosetta continues to study the ever-changing comet from a distance, the mission teams have been trying to narrow down the location of Philae on the comet nucleus using a variety of data, including imaging, magnetic field, and radio wave measurements.

Philae first touched down at the Agilkia landing site on the head of Comet 67P/C-G at 15:34 GMT on 12 November 2014, confirmation arriving back at Earth via Rosetta 28 minutes later. Unfortunately Philae's harpoons did not deploy and the ice screws alone proved insufficient to secure the lander at Agilkia. As a result, the lander rebounded for an additional two-hour flight before finally coming to rest at a site now known as Abydos.

More: http://blogs.esa.int/rosetta/2015/06/11/the-quest-to-find-philae-2/

[The Thing]

Rosetta's lander Philae wakes up from hibernation

Rosetta's lander Philae is out of hibernation!

The signals were received at ESA's European Space Operations Centre in Darmstadt at 22:28 CEST on 13 June. More than 300 data packets have been analysed by the teams at the Lander Control Center at the German Aerospace Center (DLR).

"Philae is doing very well: It has an operating temperature of -35ºC and has 24 Watts available," explains DLR Philae Project Manager Dr. Stephan Ulamec. "The lander is ready for operations."

For 85 seconds Philae "spoke" with its team on ground, via Rosetta, in the first contact since going into hibernation in November.

More: Philae is awake!

[JohnP]

Blimey that's excellent - hope that means they will be able to do more science..?

[Carole]

Excellent news.

Carole

[Kenny]

Whoop whoop!

[Fay]

Hooray, great!!

[Mike]

Let's hope it can get enough power to transmit its collected data back to Earth.

[MarkS]

Such great news.  Looking forward to the new data.

Mark

[Rick]

Philae Wake-Up Triggers Intense Planning

The receipt of signals from Rosetta's Philae lander on 13 June after 211 days of hibernation marked the start of intense activity. In coordination with its mission partners, ESA teams are working to juggle Rosetta's flight plan to help with renewed lander science investigations.

Philae has woken up after seven months in hibernation on Comet 67P/Churyumov–Gerasimenko. Hidden by shadows, Philae shut down on 15 November 2014 at 00:36 GMT after completing its main science operations sequence on the comet when the primary battery expired as expected after about 60 hours.

Since March 2015, when Philae's environmental conditions started to improve with higher surface temperatures and better illumination, the orbiter's receiver had been turned on periodically to listen for signals from the lander when the orbital geometry was thought to be optimum.

More: http://www.esa.int/Our_Activities/Operations/Philae_wake-up_triggers_intense_planning

[Carole]

As a bonus, any operation of Philae's instruments up to or through perihelion on 13 August – the comet's closest point to the Sun along its orbit – will allow in-situ study of a comet during its peak activity.

Had Philae landed at the planned site, at Agilkia in November 2014, its mission would likely have ended in March because of the higher temperatures of that location as solar illumination increased.