December 10, 2024 Quick space links
Courtesy of BtB’s stringer Jay. This post is also an open thread. I welcome my readers to post any comments or additional links relating to any space issues, even if unrelated to the links below.
- Chinese pseudo-company Space Epoch successfully completes 20-second static fire test of its stainless steel Yuanxingzhe-1 rocket
It uses methane-fuel engines, and intends to land the first stage vertically after launch.
- China’s Long March 5B to launch the first 10 satellites in the Chinese SatNet megaconstellation
According to tweet, the core stage will not reach orbit, which means it will drop into the ocean instead of crashing uncontrolled somewhere else on Earth.
- Vast touts video showing the shield design it is using on its Haven-1 space module
The video shows a test where the shield blocked 6mm projectile moving at 6.5 kilometers per second.
- On this day in 1999 Europe’s XMM space telescope was launched
The article outlines some of the space telescope’s discoveries in the past 25 years.
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
Courtesy of BtB’s stringer Jay. This post is also an open thread. I welcome my readers to post any comments or additional links relating to any space issues, even if unrelated to the links below.
- Chinese pseudo-company Space Epoch successfully completes 20-second static fire test of its stainless steel Yuanxingzhe-1 rocket
It uses methane-fuel engines, and intends to land the first stage vertically after launch.
- China’s Long March 5B to launch the first 10 satellites in the Chinese SatNet megaconstellation
According to tweet, the core stage will not reach orbit, which means it will drop into the ocean instead of crashing uncontrolled somewhere else on Earth.
- Vast touts video showing the shield design it is using on its Haven-1 space module
The video shows a test where the shield blocked 6mm projectile moving at 6.5 kilometers per second.
- On this day in 1999 Europe’s XMM space telescope was launched
The article outlines some of the space telescope’s discoveries in the past 25 years.
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
Interesting, the vessel used to recover the Gaganyaan capsule is the INS Jalashwa (Sanskrit/Hindi: Hippopotamus) is an amphibious transport dock, formerly the USS Trenton,
Fahrenheit 451 (1966)
“Montag Watches His Own Death on TV”
https://youtu.be/boBYhbT_WH4
(1:37)
“They can’t keep the viewers waiting much longer, the Show must go on…”
I find things such as this very confusing: “the shield blocked 6mm projectile moving at 6.5 kilometers per second.”
6.5 k/s _seems_ fast, but is it? It looks (via two seconds of searching) as if 9mm bullet velocity is between 900 and 1200 feet/sec. A foot is 0.0003048 kilometers. Clearly they did more than point a 6mm pistol at it and pull the trigger. That makes it seem fast. Orbital speed obviously varies, but LEO seems to be (equally fast search) around 29,000 km/h, which is about 8 km/sec. 6.5 seems both fast and reasonable (the odds of a “head-on” collision in orbit would seem to be small).
6mm is important for “will it penetrate?”, but what’s the mass? A 6mm diameter hollow plastic sphere is very different from a metric ton tungsten rod with a 6mm tip. Is there anything “interesting” about 6mm? Too small to see on radar? Arbitrarily chosen because of how the test rack works?
Not penetrating is obviously better than penetrating, but what makes this test meaningful/interesting? (
A rhetorical question, but if anyone knows, that would be awesome.)
Mark Sizer,
I once did some testing with the Ames Vertical Gun Range, and that was an experience and education. We were seeking knowledge as to the damage that might occur to our X-ray telescope’s apertures, which we wanted covered with a form of window. We were seeking materials that would not shatter if struck by a micrometeoroid but would just have a small hole (and could withstand the acoustics within a rocket fairing, but that is another story and another test facility), and NASA’s Ames Research Center was the place we did the test.
https://www.nasa.gov/wp-content/uploads/2015/04/range_factsheet_i.pdf
“6.5 k/s _seems_ fast, but is it?”
Not really. As you noted, low Earth orbital speed is just about 8 km/s, so an object in an orbit just 60° different would have a closing speed of 8 km/s, too. If it comes from outside Earth orbit, it would be at least 40% faster than orbital speed. Things travel fast in space, so collisions can be catastrophic. That is what the shield is for — it is the one that gets perforated by the disintegrating projectile so that the inner hull (pressure vessel) is only struck by much smaller and much slower debris or gas from the initial collision.
“6mm is important for “will it penetrate?”, but what’s the mass?”
The energy to be dissipated is only linearly proportional to the mass, but it is proportional to the square of the speed, which is clearly the important parameter for this test.