Philae status update
Engineers on the Rosetta team are struggling to figure out why they cannot get a solid communications lock with their Philae lander, and have come up with several explanations.
One possible explanation being discussed at DLR’s Lander Control Center is that the position of Philae may have shifted slightly, perhaps by changing its orientation with respect to the surface in its current location. The lander is likely situated on uneven terrain, and even a slight change in its position – perhaps triggered by gas emission from the comet – could mean that its antenna position has also now changed with respect to its surroundings. This could have a knock-on effect as to the best position Rosetta needs to be in to establish a connection with the lander.
Another separate issue under analysis is that one of the two transmission units of the lander appears not to be working properly, in addition to the fact that one of the two receiving units is damaged. Philae is programmed to switch periodically back and forth between these two transmission units, and after tests on the ground reference model, the team has sent a command to the lander to make it work with just one transmitter. As Philae is able to receive and accept commands of this kind in the “blind”, it should execute it as soon as it is supplied with solar energy during the comet’s day.
They have heard from Philae since July 9. Because of comet activity they have had to pull Rosetta back away from the nucleus to protect it, and are now focusing its primary activity on observations, not communications with Philae. They will continue to try to bring Philae back to full functioning life, but the priority is now the comet.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon or from any other book seller. If you want an autographed copy the price is $60 for the hardback and $45 for the paperback, plus $8 shipping for each. Go here for purchasing details. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
Engineers on the Rosetta team are struggling to figure out why they cannot get a solid communications lock with their Philae lander, and have come up with several explanations.
One possible explanation being discussed at DLR’s Lander Control Center is that the position of Philae may have shifted slightly, perhaps by changing its orientation with respect to the surface in its current location. The lander is likely situated on uneven terrain, and even a slight change in its position – perhaps triggered by gas emission from the comet – could mean that its antenna position has also now changed with respect to its surroundings. This could have a knock-on effect as to the best position Rosetta needs to be in to establish a connection with the lander.
Another separate issue under analysis is that one of the two transmission units of the lander appears not to be working properly, in addition to the fact that one of the two receiving units is damaged. Philae is programmed to switch periodically back and forth between these two transmission units, and after tests on the ground reference model, the team has sent a command to the lander to make it work with just one transmitter. As Philae is able to receive and accept commands of this kind in the “blind”, it should execute it as soon as it is supplied with solar energy during the comet’s day.
They have heard from Philae since July 9. Because of comet activity they have had to pull Rosetta back away from the nucleus to protect it, and are now focusing its primary activity on observations, not communications with Philae. They will continue to try to bring Philae back to full functioning life, but the priority is now the comet.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon or from any other book seller. If you want an autographed copy the price is $60 for the hardback and $45 for the paperback, plus $8 shipping for each. Go here for purchasing details. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News