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View Full Version : New Research Casts Doubt on the Late Heavy Bombardment



Fraser
2012-Jan-05, 02:00 PM
Was the early solar system bombarded with lots of big impacts? This is a question that has puzzled scientists for over 35 years. And it’s not just an academic one. We know from rocks on Earth that life began to evolve very early on, at least 3.8 billion years ago. If the Earth was being [...]

More... (http://www.universetoday.com/92375/new-research-casts-doubt-on-the-late-heavy-bombardment/)

Perikles
2012-Jan-05, 03:02 PM
OK - I admit I am completely baffled by this:

Scientists know the relative ages of such lunar basins because of a concept called superposition. Basically, superposition states that what is on top must be older than what’s underneath. Why is this so?

IsaacKuo
2012-Jan-05, 04:55 PM
OK - I admit I am completely baffled by this:
Why is this so?
Looks like a typo, that was corrected. It's now this:

"Basically, superposition states that what is what is on top must be younger than what is beneath."

Perikles
2012-Jan-05, 04:58 PM
Looks like a typo, that was corrected. It's now this:

"Basically, superposition states that what is what is on top must be younger than what is beneath."Thanks - that's a relief.