help - trivia question!

oooh

good point TT!!

thanx

On 3 Jul 2005 18:14:09 -0700, "spider_and_i"
wrote:

If these two celestial objects [Note: Single objects - NOT a class or
category of objects or multiple representatives of a single type of
object] did not exist, most scientists believe that life on Earth
probably would never have evolved. Name the 2 objects.

im guessing jupiter & the sun - is that right?

I'd go with Jupiter and the Moon. Jupiter is a bigger maybe since its
influence on the Earth's development is more speculative. The Moon
because of its tides, which are considered by many to have created the
conditions that helped life evolve beyond the most primitive state. The
Sun is absolutely required, of course- no "probably" there.

_________________________________________________

Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

Greg Crinklaw wrote:
Sam Wormley wrote:

The Sun (Marty) provides an energy source for the Earth, drives
the weather, etc. and the Moon provides axial stability, increases
tides, and takes a lot of impacts that would otherwise hit the
Earth. Jupiter have very little influence on the Earth.


Not necessarily. There is a fairly mainstream school of thought that
says the earth wouldn't even be here if it weren't for Jupiter...


Granted--Similarly the Earth had to be impacted by a Mars like
body to create our Moon. So can it be argued that we needed the
solar system we occupy for life to have evolved on the Earth, Mars,
moons of Jupiter, etc.?

thanx to all for your help!

thanx to all for your help!


So when will you find out the correct answer?

-Florian

tomorrow morning

tomorrow morning


Be sure to let us know! ;-)

-Florian

Chris L Peterson wrote:
I'd go with Jupiter and the Moon. Jupiter is a bigger maybe since its
influence on the Earth's development is more speculative. The Moon
because of its tides, which are considered by many to have created the
conditions that helped life evolve beyond the most primitive state. The
Sun is absolutely required, of course- no "probably" there.

At first, I thought "Sun and Moon." But on second thought, I agree with
you: The Sun is likely not an answer, since (a) as you say, there's no
"probably" about it; and (b) it's in the same class of answer as "Earth."
The question doesn't make much sense without the Earth, and you can't
really have the Earth forming (as we know it) without the Sun.

The Moon is a good one, and I'll go with Jupiter, too.

Brian Tung
The Astronomy Corner at http://astro.isi.edu/
Unofficial C5+ Home Page at http://astro.isi.edu/c5plus/
The PleiadAtlas Home Page at http://astro.isi.edu/pleiadatlas/
My Own Personal FAQ (SAA) at http://astro.isi.edu/reference/faq.txt

spider_and_i wrote:
im guessing jupiter & the sun - is that right?

sorry, I only saw this post this evening (July 5).

it's Jupiter and the Moon, but not for any of the reasons given so far.

Jupiter: was instrumental in scattering most planetesimals out of the
solar system early on. if not for Jupiter, the "Late Heavy Bombardment"
that pummeled the Moon and inner planets from 3.9 to 3.1 billion years
ago would still be going on. life would not have had a chance to
develop between so-humongous-that-Earth-is-sterilized maga impacts.

Moon: has stabilized Earth's obliquity (axial tilt) over time, such
that the variations in tilt are only +/- 1.5 degrees. without it, Earth
would have wild swings like those of Mars, which vary from 5 to 35
degrees. under those circumstances periodic climate change would be so
radical that life could not get a stable foothold.

clear skies.
Kelly

Kelly Beatty wrote:
Jupiter: was instrumental in scattering most planetesimals out of the
solar system early on. if not for Jupiter, the "Late Heavy Bombardment"
that pummeled the Moon and inner planets from 3.9 to 3.1 billion years
ago would still be going on. life would not have had a chance to
develop between so-humongous-that-Earth-is-sterilized maga impacts.

Moon: has stabilized Earth's obliquity (axial tilt) over time, such
that the variations in tilt are only +/- 1.5 degrees. without it, Earth
would have wild swings like those of Mars, which vary from 5 to 35
degrees. under those circumstances periodic climate change would be so
radical that life could not get a stable foothold.

Strange--I thought these reasons were offered earlier in the thread.
Weren't they?

Oh, I do remember that the Moon was cited for tides. But that would
only be a reason for *land* life to get started, not all life in general.
The original life that helped to transform the atmosphere from a reducing
one to an oxidizing one would probably have developed anyway.

But didn't someone mention Jupiter's comet-ejecting power?

Brian Tung
The Astronomy Corner at http://astro.isi.edu/
Unofficial C5+ Home Page at http://astro.isi.edu/c5plus/
The PleiadAtlas Home Page at http://astro.isi.edu/pleiadatlas/
My Own Personal FAQ (SAA) at http://astro.isi.edu/reference/faq.txt