Chang’e-5’s lunar samples less dense than expected
Because the lunar samples retrieved by China’s Chang’e-5 probe were less dense than expected, it ended up recovering only 3.8 pounds of material rather than the targeted 4.4 pounds.
The probe had estimated the lunar rocks to have a density of 1.6 grams per cubic millimetre, based on data from past missions by other countries, said Pei Zhaoyu, the mission spokesman. Going by that figure, the probe stopped taking samples after just 12 hours, apparently assessing that the target had been reached. “However, from tests, the actual density might not be that high,” Pei told reporters.
This is not a failure, but a discovery. In order to make sure the lander did not recover too much material, weighing too much, they needed to set limits based on the expected weight of the material recovered. That these samples taken from the Mons Rümker volcano complex are lighter than expected reveals something about them. It suggests the lava here was different than lava samples taken elsewhere.
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
Because the lunar samples retrieved by China’s Chang’e-5 probe were less dense than expected, it ended up recovering only 3.8 pounds of material rather than the targeted 4.4 pounds.
The probe had estimated the lunar rocks to have a density of 1.6 grams per cubic millimetre, based on data from past missions by other countries, said Pei Zhaoyu, the mission spokesman. Going by that figure, the probe stopped taking samples after just 12 hours, apparently assessing that the target had been reached. “However, from tests, the actual density might not be that high,” Pei told reporters.
This is not a failure, but a discovery. In order to make sure the lander did not recover too much material, weighing too much, they needed to set limits based on the expected weight of the material recovered. That these samples taken from the Mons Rümker volcano complex are lighter than expected reveals something about them. It suggests the lava here was different than lava samples taken elsewhere.
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
Typo correct (I think …), first sentence, “recovering on 3.8 ….” … it sounds like it was supposed to be “recovering only 3.8 ….”
Best line in the story: “This is not a failure, but a discovery. “
janyuary: Typo fixed. Thank you!
What would I do without my readers?
“This is not a failure, but a discovery. “
I have a similar feeling about the crack in the Russian ISS module.
ISS is up there so scientists and engineers can discover what it takes to build and maintain a habitat in space.
The module has been up there 20 years – it is not a failure.
If the crack is unexpected then it’s likely something can be learned from its cause (and lessons regarding locating the leak).
The Russians should be proud of it’s accomplishments and not so secretive about it’s imperfections.