August 11, 2025 Quick space linksCourtesy 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.
- Long March 10’s first stage is geared up for its first static fire of all seven engines
This is the heavy lift rocket China is developing for its manned lunar missions, capable of putting 70 tons in Earth orbit and 27 tons toward the Moon. Jay: “They did a firing of just three of the engines a couple months ago.” First test launch is targeting 2026.
- On this day in 1966 Lunar Orbiter 1 was launched to the Moon
Its main goal was to provide high resolution images of the planned Apollo landing sites. It also got the first Earthrise picture, as well as high resolution images of 50% of the far side of the Moon. Its orbit also revealed the first hint of the Moon’s uneven gravity and underground mass concentrations (mascons), making all orbits unstable.
- On this day in 1990 the Magellan spacecraft entered orbit around Venus
It mapped 90% of Venus’ surface using radar, revealing a planet with millions of volcanoes and no obvious plate tectonics.
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
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.
- Long March 10’s first stage is geared up for its first static fire of all seven engines
This is the heavy lift rocket China is developing for its manned lunar missions, capable of putting 70 tons in Earth orbit and 27 tons toward the Moon. Jay: “They did a firing of just three of the engines a couple months ago.” First test launch is targeting 2026.
- On this day in 1966 Lunar Orbiter 1 was launched to the Moon
Its main goal was to provide high resolution images of the planned Apollo landing sites. It also got the first Earthrise picture, as well as high resolution images of 50% of the far side of the Moon. Its orbit also revealed the first hint of the Moon’s uneven gravity and underground mass concentrations (mascons), making all orbits unstable.
- On this day in 1990 the Magellan spacecraft entered orbit around Venus
It mapped 90% of Venus’ surface using radar, revealing a planet with millions of volcanoes and no obvious plate tectonics.
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
Magellan also revealed a dearth of antique craters on Venus. But it, as with all the other terrestrial rocky worlds of the inner solar system (including the moon), must have been pummeled by many gigantic not to speak of lesser impacts during (e.g.) the solar system’s “Late Heavy Bombardment” era of about 4 billion years ago.
The lack of any such old craters (and only a relatively few new) on the venusian surface shows that—apparently as a result of internal heat buildup due to Venus’ geological so-called “stagnant lid” tectonics—the planet’s surface got thoroughly resurfaced around half a billion years back, in a stupendously catastrophic event whereby the planet’s entire crust basically turned over and melted, thereafter resolidifying again with the (since lightly cratered) surface that we see.
This wholly geological cataclysm—not a mythical, climatological, “runaway greenhouse effect”—appears to be what propelled Venus’ entire sequestered stock of crustal carbon (if any was still in the ground at that point—as these planet-wide disasters may have occurred [up to 6-8 times] before) into the atmosphere as CO2.
Thus the dangers of “stagnant-lid” tectonics for worlds (not just planets) in our universe.
Preliminary indications of the scarcity of ancient impact craters on Venus actually came before NASA’s Magellan mission, from the Soviet orbiters Venera 15 and Venera 16, launched in 1983. Operating in near-polar orbits, these spacecraft used synthetic aperture radar to map roughly 25% of the Venusian surface, mainly in the high northern latitudes (north of about 30°). With a spatial resolution of about 1–2 km, their data were far less detailed than Magellan’s later 120–300 m resolution, but they were sufficient to reveal large-scale geological features, extensive volcanic plains, and an apparent absence of heavily cratered ancient terrain.
However, it was Magellan (1990–1994) that provided the global confirmation and temporal context for this observation. By mapping about 98% of the surface at much higher resolution, Magellan demonstrated that the paucity of old craters was a planet-wide phenomenon and not confined to the regions imaged by the Soviet orbiters, thus strengthening the hypothesis of a global resurfacing event about 500 million years ago.
Shocking news from Russia: Luna 27 has run into delays.
https://interfax.com/newsroom/top-stories/113182/
To Michael,
I wonder if Venus had CO2 that far back –which held heat in to help cause that overturn.
No life, no carbonate rock-no chance.
A dense, early atmosphere would also prevent all but the largest craters anyway.
On the contrary, Venus’ atmosphere—like Earth’s—thick though the former is compared with the latter, would nonetheless provide essentially no protection against the scale of impacts of the Late Heavy Bombardment (and occasionally after), such as one sees on the Moon in its maria and great craters like Tycho and Copernicus.
Beyond that, it’s the thick, unbroken (unfragmented into “plates”) crust of a “stagnant-lid” world that holds in the mantle and core’s heat—leading to eventual crustal overturn—not the relatively mild heat and temperature of the present venusian surface, which is wholly insufficient to cause such a geological cataclysm. (It might happen on Mars too someday, whose present core and mantle—contrary to myth—is considerably more molten than Earth’s, which pace people’s intuition is why Mars lacks a planetary magnetic field.)