ESA Lands a Spacecraft on a Comet for the First Time – UPDATE

The European Space Agency (ESA) landed a spacecraft on a comet today, the first time such a feat has been achieved.  The Philae lander was separated from its Rosetta mothership early this morning Eastern Standard Time (EST) and landed just after 10:30 am EST.   Scientists and people around the world waited anxiously for the 28 minutes 20 seconds it takes for a signal to travel the 510 million kilometers from the comet to Earth to learn that the landing was successful.  

Confirmation of the landing was expected at 11:02:20 am EST and shortly after that cheering broke out at the operations center in Europe.  That was followed by several minutes of serious-looking faces as they studied the data coming back, creating some worry.  The word “bounce” was heard.  But soon thereafter, Philae project manager Stephan Ulamec from German’s space agency DLR announced the good news that Philae was safe and sound on the surface of Comet 67P/Churyumov-Gerasimenko.  “Philae is talking to us, the harpoons have fired, we are sitting on the surface.  We are on the comet.”

Comets have almost no gravity, so Philae was design to attach itself to the surface with harpoons and screws.   Although Ulamec initially said that harpoons had fired, ESA tweeted within an hour that, in fact, they did not. 

ESA Operations ‏@esaoperations 

More analysis of @Philae2014 telemetry indicates harpoons did not fire as 1st thought. Lander in gr8 shape.
Team looking at refire options

 

The first images from Philae of the comet’s surface are expected to reach Earth and be released by ESA in about two hours (around 1:00 pm EST).  

Already, ESA provided two intriguing images, however.   The first is a photograph of the Rosetta mothership taken by Philae 50 seconds after the two separated.   The second is a photograph of Philae taken by Rosetta as Philae descended to the comet’s surface. 

 

The body and one solar panel of ESA’s Rosetta spacecraft can be seen in the upper part of this photo, taken
by the Philae lander 50 seconds after the two spacecraft separated.  The bright light  is the Sun.  November 12, 2014.
Credit: ESA/Rosetta/Philae/CIVA

Image of ESA’s Philae lander as it descends to land on Comet 67P/Churyumov-Gerasimenko, taken by the OSIRIS
camera on the Rosetta spacecraft.  Philae’s three landing legs are clearly visible.  November 12, 2014.  Credit:
ESA/Rosetta/MPS

ESA named the landing site on Comet 67P “Agilkia.” 

ESA says Rosetta and Philae “aim to unlock the mysteries of the oldest building blocks of our solar system — comets” and hence the names are connected to the deciphering of hieroglyphics. 

• Rosetta is named after the Rosetta Stone that allowed the deciphering of hieroglyphics and therefore an understanding of Egyptian civilization.
• Philae is the name of an island in the Nile river where an obelisk was found with the final clues to enable the decryption.
• Philae was flooded when the Aswan dams were built in the 20th century and a complex of Ancient Egyptian buildings, including the Temple of Isis, were moved to another island, Agilkia,   ESA held a contest to name Philae’s landing site on 67P and of 8,000 entries, more than 150 suggested Agilkia and that was the winner.

The comet is named after the two Kiev, Ukraine astronomers who discovered it in 1969, Klim Churyumov and Svetlana Gerasimenko, while conducting comet observations at the Alma-Ata Astrophysical Institute in Kazakhstan.

Rosetta is an ESA mission, but NASA provided three of its instruments.

Note:  This article was updated at 11:55 am EST November 12 after ESA announced that the harpoons had not, in fact, fired.