China's lunar rock samples show lava flowed on the moon 2 billion years ago:
Lava oozed across the moon's surface just 2 billion years ago, bits of lunar rocks retrieved by China's Chang'e-5 mission reveal.
A chemical analysis of the volcanic rocks confirms that the moon remained volcanically active far longer that its size would suggest possible, researchers report online October 7 in Science.
Chang'e-5 is the first mission to retrieve lunar rocks and return them to Earth in over 40 years (SN: 12/1/20). An international group of researchers found that the rocks formed 2 billion years ago, around when multicellular life first evolved on Earth. That makes them the youngest moon rocks ever collected, says study coauthor Carolyn Crow, a planetary scientist at the University of Colorado Boulder.
The moon formed roughly 4.5 billion years ago. Lunar rocks from the Apollo and Soviet missions of the late 1960s and 70s revealed that volcanism on the moon was commonplace for the first billion or so years of its existence, with flows lasting for millions, if not hundreds of millions, of years.
Given its size, scientist thought that the moon started cooling off around 3 billion years ago, eventually becoming the quiet, inactive neighbor it is today. Yet a dearth of craters in some regions left scientists scratching their heads. Parts of celestial bodies devoid of volcanism accumulate more and more craters over time, in part because there aren't lava flows depositing new material that hardens into smooth stretches. The moon's smoother spots seemed to suggest that volcanism had persisted past the moon's early history.
"Young volcanism on a small body like the moon is challenging to explain, because usually small bodies cool fast," says Juliane Gross, a planetary scientist at Rutgers University in Piscataway, N.J., not involved in the study.
Scientist had suggested that radioactive elements might offer an explanation for later volcanism. Radioactive decay generates a lot of heat, which is why nuclear reactors are kept in water. Enough radioactive materials in the moon's mantle, the layer just below the visible crust, would have provided a heat source that could explain younger lava flows.
Journal Reference:
Xiaochao Che, Alexander Nemchin, Dunyi Liu, et al. Age and composition of young basalts on the Moon, measured from samples returned by Chang’e-5, Science (DOI: https://www.science.org/doi/10.1126/science.abl7957)
(Score: 1, Troll) by Rosco P. Coltrane on Thursday October 14 2021, @01:17PM (6 children)
I know the science is great, and I know it's quite a technical feat. But sadly anything the Chinese do on the moon all feels a bit me-too. Such debauchery of technical means to find out lava flowed on the moon 2 BILLION years ago - and scientists going all uuh-aah over "young" volcanism. I mean gee, say what you will, it's boring as shit. I know I should, but I'm really struggling to care.
On the bright side, I believe those me-too baby steps with boring science thrown in are all in preparation for new and genuinely exciting manned lunar missions.
(Score: 4, Insightful) by DannyB on Thursday October 14 2021, @01:58PM (2 children)
One thing China is fantastic at doing is "me too". And I mean that sincerely. They not only do "me too", but they do it faster and cheaper.
Satin worshipers are obsessed with high thread counts because they have so many daemons.
(Score: 2) by hendrikboom on Thursday October 14 2021, @04:34PM (1 child)
It does cost less to do something the second time.
It costs more if you specify you'll pay cost-plus in the contract.
(Score: 3, Informative) by DannyB on Thursday October 14 2021, @05:29PM
It certainly costs less if you don't have to do all of the original R&D. Even if SpaceX keeps some things secret, those secrets may be fairly easy to deduce.
SpaceX has already demonstrated a lot of what "not to do", and "what to do". For example, grid fins to steer the rocket to the landing pad. At the last moments before landing Blue Origin's New Shepard seems to use a lot of engine power to guide the rocket to the pad and then set it down gently. SpaceX Falcon 9 seems to light the engine at the right moment and just run out of fuel and have no velocity as the rocket touches the pad.
Another lesson from SpaceX. Maybe having lots of engines on a F9 isn't as big a reliability problem as people thought. And they are reusable!
Reusability isn't an item you just bolt on after the fact. It needs to be considered in every part of the initial design. From engines to seat belts.
One way to learn a lot of things without doing R&D is to have spies. Just how big are the two sub critical mass pieces? What velocity should they impact? What's the best way to compress plutonium? Etc.
Satin worshipers are obsessed with high thread counts because they have so many daemons.
(Score: 1, Touché) by Anonymous Coward on Thursday October 14 2021, @02:08PM
The world was enraptured by Apollo 11. By Apollo 14, nobody cared.
That's what we need. We need space exploration to become so cheap and routine that only the explorers themselves, children, and turbo-nerds are excited by it.
(Score: 0) by Anonymous Coward on Thursday October 14 2021, @02:54PM (1 child)
I will say, no, it is not "boring as shit." I fear for science as we slide in the direction of determining our long term research roadmaps based on things like Facebook polls. My only hope is that groups such as the National Academies can hold back that dam until we as a society have moved on from social media "likes" and other measures of popularity on to whatever the next paradigm becomes, or until the societal pendulum swings back to another age of valuing knowledge.
(Score: 2) by hendrikboom on Thursday October 14 2021, @04:36PM
Shit is not boring at all. It is unpleasant. It stinks, and after voiding it you avoid it.
(Score: 1, Offtopic) by DannyB on Thursday October 14 2021, @02:00PM
Just because lava may have oozed across the lunar surface does not mean that it contained any life or microorganisms.
Satin worshipers are obsessed with high thread counts because they have so many daemons.
(Score: 0) by Anonymous Coward on Thursday October 14 2021, @03:06PM (1 child)
Would they be able to tell the difference between melted rock from a volcano and melted rock from a large meteor? Maybe they landed near an asteroid strike that occurred 2 billion years ago.
(Score: 0) by Anonymous Coward on Thursday October 14 2021, @05:16PM
IANAAD, but I would expect lava rock formed from relatively slow moving lava would have different structures comoared to rocks formed by a flash explosion.
(Score: 0) by Anonymous Coward on Thursday October 14 2021, @03:07PM
The abstract:
And here is some background for the implications of these measurements: