is earth positioned perfecly vis-a-vis the sun?

On 27 Mar 2004 12:26:14 +0200, Marvin
wrote:

Michael Johnson wrote in
:

On Fri, 19 Mar 2004 02:57:36 GMT, "OhBrother"
wrote:

On Thu, 18 Mar 2004 18:50:58 -0800, Chris wrote:


"Greg D. Moore (Strider)" wrote in
message ...

"meat n potatoes" wrote in message
om...
obviously for the sake of life, better positioned than venus or
mars.

[snip]

okay, now imagine a sci-fi scenario. can we build a device on
earth that takes us a little further away from or closer to the
sun? let's say a giant rocket launcher with the blasters facing
against the sky. so when we blast it, the earth moves in one or
other direction? or is this just ridiculous?

I heard that the earth get warmer the further the sun is from the
earth (summer) and colder the closer it gets. So if the sun fell on
the earth we would freeze to death?


Heh!

Well, if a giant rocket blaster was positioned to push the earth even
the smallest amount away from the sun (elongating the orbit which is
reasonably stable right now)

How exactly would you position this blaster on oh ya.. A SPINNING BODY
so that it would give a lateral 'push' outward? I think someone needs
to go relearn basic phyiscs.

Second, if you want to change the orbit of the earth, its my
understanding the normal way is you have to change the velocity at
which the earth is going around the sun? And in order to do that, you
need to change the mass of either the earth or the sun, and good luck
there. Bear in mind its not the same as transform. Due to
conservation, unless you brought in a ton of mass from the outside the
earth will always have the same mass it did before. The sun will
change mass over its lifetime, but not any time soon. But assuming
your original movement of a body to a different orbit were capable,
the velocity the earth is going around the sun should be different
than the velocity Jupiter is going around the sun. And if Earth was
placed in say Jupiter's orbit without a change in the velocity, it
would never adhere to that orbital path. What would probably happen,
assuming the forces didn't tear it apart or it ran into stuff on the
way is that assuming the gravity of the sun was still the primary
force on the earth, it would get pulled closer to the sun and
whipsawed around until the earth settled onto its original orbital
path given its mass and velocity.

-MJ

Umm, on second thought, NO ONE can possibly be this stupid and still retain
enough brain function to breathe. You are obviously a troll, and are thus
consigned to the troll-cage where you belong.

Yup.. a flamer. That's twice now you responded with 0 knowledge to
add. *shrug* okie... if that's your thing have at it.

-MJ

Michael Johnson wrote in
:

On 19 Mar 2004 14:08:47 +1300, Llanzlan Klazmon The 15th
wrote:

(meat n potatoes) wrote in
.com:

obviously for the sake of life, better positioned than venus or
mars.

okay, two questions.

1. how far can earth be placed further or closer to the sun while
still maintaing the existence of life, no matter how simple?


The earth's orbit around the Sun is eccentric. It's closest approach
to the Sun is about 3,000,000 miles closer than its' furtherest
distance. So there is already over 3% variation in distance over the
year. In answer to your question though. I would say that we wouldn't
want to be too much closer to the Sun than we are but could be ok
somewhat further away. It is thought that life on earth can not
survive more than about 1GYA more because the Sun is gradually heating
up as it develops along its' main sequence evolution. In about 5GYA
the sun is expected to leave the main sequence and expand into a red
giant phase as it commences Helium burning .

Okie.. i don't know which is stupider.. his original post or your
response. I did love the mixing in of acronyms like GYA without
expaining what a GYA was so as to make you sound smart, while in truth
you're probably just someone who at best read a bit farther in college
and thinks running the lingo even remotely denotes intelligence.


This is a science group, therfore science lingo. If you actually have
anything to criticise on the facts I posted then let's hear it, otherwise
quit whining.


2. are we perhaps not perfectly postioned? would we better off if we
were placed a little closer or further away? do you think our
greenhouse problem will be alleviated if we move a little away from
the sun?
would we have better seasons and better crops if we were a bit
closer to the sun?

okay, now imagine a sci-fi scenario. can we build a device on earth
that takes us a little further away from or closer to the sun?
let's say a giant rocket launcher with the blasters facing against
the sky. so when we blast it, the earth moves in one or other
direction? or is this just ridiculous?


The way to move the earth outward would be to modify the orbits of
comets and asteroids to kick the earth into a higher orbit using a
reverse slingshot effect. It would take an awfull lot of comets though
:-

...

An easier way that might work for a while would be to put big sun
shades into orbit.
...

NM! You got some real problems bud.


Your problem is to learn to read for comprehension.

As per the original question, granted this is pure opinion from an
uninformed source, but from everything i've read Earth is positioned
in its current orbit because that's where the gravity interaction
between the bodies of the earth and the sun has settled it over time.

I said nothing about why the Earth's orbit happens to be where it is. Nor
did the original poster ask that. However from what we can detect of
extrasolar planetary systems - all sorts of outcomes are possible for their
formation. Look up "hot jupiters" for example.


I.e. if it were pushed only moderately farther out or in, so long as
the gravity between the two bodies still interacted it would get
pulled back onto its original track.

Wrong. Learn some elementary orbital mechanics.


Either way, the amount of work
and power needed to accomplish such a feat would almost certainly
destroy the earth on its own.

Not using the method I suggested, which was tongue in cheek BTW. Also the
sunshade scheme could be a viable way to reduce solar radiation.

SNIP

LK.

"Michael Johnson" wrote in message
...

How exactly would you position this blaster on oh ya.. A SPINNING BODY
so that it would give a lateral 'push' outward? I think someone needs
to go relearn basic phyiscs.

Easy, you only have it "on" 1/2 the time. Not as effecient as one might
like, but doable.


Second, if you want to change the orbit of the earth, its my
understanding the normal way is you have to change the velocity at
which the earth is going around the sun? And in order to do that, you
need to change the mass of either the earth or the sun, and good luck
there.

Your understanding is wrong. Remember what Galileo taught us about falling
masses.