India launches its first attempt to do an in-space docking demo
India’s space agency ISRO today successfully launched a mission, dubbed Spadex, to make its first attempt to do an in-space unmanned docking between two satellites, its PSLV rocket lifting off from its coastal Sriharikota spaceport. From the Spadex mission webpage:
The SpaDeX mission consists of two small spacecraft (about 220 kg each) to be launched by PSLV-C60, independently and simultaneously, into a 470 km circular orbit at 55° inclination, with a local time cycle of about 66 days. The demonstrated precision of the PSLV vehicle will be utilized to give a small relative velocity between the Target and Chaser spacecraft at the time of separation from the launch vehicle. This incremental velocity will allow the Target spacecraft to build a 10-20 km inter-satellite separation with respect to the Chaser within a day. At this point, the relative velocity between the Target will be compensated using the propulsion system of the Target spacecraft.
At the end of this drift arrest maneuver, the Target and Chaser will be in the same orbit with identical velocity but separated by about 20 km, known as Far Rendezvous. With a similar strategy of introducing and then compensating for a small relative velocity between the two spacecraft, the Chaser will approach the Target with progressively reduced inter-satellite distances of 5 km, 1.5 km, 500 m, 225 m, 15 m, and 3 m, ultimately leading to the docking of the two spacecraft. After successful docking and rigidization, electrical power transfer between the two satellites will be demonstrated before undocking and separation of the two satellites to start the operation of their respective payloads for the expected mission life of up to two years.
For India’s plans to build a manned space station this capability is essential. It will also be needed for its plans to send humans to the Moon.
As this was only India’s fifth launch in 2024, the leader board for the 2024 launch race remains unchanged:
136 SpaceX
65 China
17 Russia
14 Rocket Lab
American private enterprise still leads the rest of the world combined in successful launches 156 to 98, while SpaceX by itself leads the entire world, including American companies, 136 to 118.
At the moment only one more launch remains in 2024, a SpaceX Falcon 9 launch scheduled for tomorrow night. I will be publishing my year-end global launch report later this week.
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. from any other book seller, or direct from my ebook publisher, ebookit.
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
India’s space agency ISRO today successfully launched a mission, dubbed Spadex, to make its first attempt to do an in-space unmanned docking between two satellites, its PSLV rocket lifting off from its coastal Sriharikota spaceport. From the Spadex mission webpage:
The SpaDeX mission consists of two small spacecraft (about 220 kg each) to be launched by PSLV-C60, independently and simultaneously, into a 470 km circular orbit at 55° inclination, with a local time cycle of about 66 days. The demonstrated precision of the PSLV vehicle will be utilized to give a small relative velocity between the Target and Chaser spacecraft at the time of separation from the launch vehicle. This incremental velocity will allow the Target spacecraft to build a 10-20 km inter-satellite separation with respect to the Chaser within a day. At this point, the relative velocity between the Target will be compensated using the propulsion system of the Target spacecraft.
At the end of this drift arrest maneuver, the Target and Chaser will be in the same orbit with identical velocity but separated by about 20 km, known as Far Rendezvous. With a similar strategy of introducing and then compensating for a small relative velocity between the two spacecraft, the Chaser will approach the Target with progressively reduced inter-satellite distances of 5 km, 1.5 km, 500 m, 225 m, 15 m, and 3 m, ultimately leading to the docking of the two spacecraft. After successful docking and rigidization, electrical power transfer between the two satellites will be demonstrated before undocking and separation of the two satellites to start the operation of their respective payloads for the expected mission life of up to two years.
For India’s plans to build a manned space station this capability is essential. It will also be needed for its plans to send humans to the Moon.
As this was only India’s fifth launch in 2024, the leader board for the 2024 launch race remains unchanged:
136 SpaceX
65 China
17 Russia
14 Rocket Lab
American private enterprise still leads the rest of the world combined in successful launches 156 to 98, while SpaceX by itself leads the entire world, including American companies, 136 to 118.
At the moment only one more launch remains in 2024, a SpaceX Falcon 9 launch scheduled for tomorrow night. I will be publishing my year-end global launch report later this week.
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. from any other book seller, or direct from my ebook publisher, ebookit. 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
I’ve been keeping track of your launch reporting, Richard, and my spreadsheet now shows 5 Indian launches:
01-01
02-17
08-15
12-05
12-30
Michael McNeil: You are right about the count, but wrong about my first name. :) I somehow forgot to add the four launch to my totals at the beginning of December. Thank you! I have corrected the totals.
UPDATE: It appears my mistake was to enter the fourth Indian launch to Europe’s total. I have now corrected both. Your correction thus helped correct two errors. Thank you again!
I’m so sorry about getting your name wrong, Robert! I do know what your name is—which I’ve mentioned numerous times (correctly and positively) in postings before others. (For instance…) It was a typo of the brain, not the fingers as usual. What’s the saying? “Against typos even the Gods themselves contend in vain?” Or something like that…
Michael McNeil: No apology was necessary. I make more than enough typos to not be bothered by others. And your spotting of the India count error was very greatly appreciated by me. It forced me to fix both it and the Europe count error.