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64

This discovery is news because the water found is in a sunlit area, the Clavius Crater. Previous water discoveries were all in 'cold traps', which are areas where sunlight cannot reach, so water resources on the moon for colonies or space exploration was thought to have been limited to permanently shaded areas - the rest was thought to have been boiled off ...


34

Why would these be used instead of just using a larger first stage? Strapping on differently-sized boosters allows variance in payload mass without redesign of the first stage. The PSLV has flown with no (PSLV-CA), small as shown (PSLV-G), or big (PSLV-XL) solid boosters. PSLV-CA (no boosters) - can deliver 1100 kg to 622 km sun-synchronous orbit PSLV-G (...


27

It is news because the 6.1 $\mu$m wavelength measured is unique to $\rm{H_2O}$. All prior evidence included $\rm{OH}$ groups as well, thus did not show clear proof of presence of "$\rm{H_2O}$". So, now we know there is $\rm{H_2O}$ and not just any random $\rm{OH}$ group containing moleculas. Anyway, the amount measured still is ~100x less water per ...


9

The answer already posted is excellent. All I want to add is a follow-up question you might want to ask, and my answer to it. Q: OK, so those in particular aren't boosters. But would it ever make sense to use lots of tiny boosters instead of one big one? A: Yes, for two main reasons. One is the extreme expense of anything involved in space flight, and ...


1

I am not a lawyer. Still, I would like to submit this strawman answer to my own question, for you to criticize. The language of Article VI is open to different interpretations. I can see at least two, and mutually contradicting. The first, call it the “strict interpretation”, is that ONLY the US can “authorize and continuously supervise” the activities of ...


1

I'm not aware of any structured courses for a 10 year old, but that doesn't mean they don't exist. In the meantime I would recommend your son watch good quality documentaries, such as those produced by: The BBC Nova National Geographic Anything presented by Neil deGrasse Tyson, such as the 2014 continuation of Cosmos Anything presented by Brian Cox ...


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