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Planet closest to us

by jbobay2339
Tags: closest, planet
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jbobay2339
#1
Feb23-12, 11:55 AM
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OK I'm fairly new to these topics but eager to learn but as I'm sure most of you know the closest know habitable planet is gliese 581g. They say at 11 miles a sec it will take 79 years but I'm wondering does that take into account the universes expansion and would it be 79 earth years and if so wouldn't time be going slower for someone traveling at that speed. I realizes its not a very technical question but its just a curious thought I had. Thanks
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Ryan_m_b
#2
Feb23-12, 12:04 PM
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Welcome to the forum. Currently we do not know of any other habitable planet other than Earth; whilst it is located within the habitable zone where water could form we do not even know if it is a solid planet (it is also several times the mass of Earth). On top of that for something to be habitable we require a biosphere, specifically one we have evolved to cope with.

The distance to gliese 581g is ~20 light years which is 5.87 trillion miles! At a mere 11 miles per second it would take roughly 17,000 years.

The expansion of the universe is minute and at this distance would not make a difference.
jbobay2339
#3
Feb23-12, 12:08 PM
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Haha thanks that answered that as you can tell I've just started some reading and learning but I love this stuff

Ryan_m_b
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Feb23-12, 12:10 PM
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Planet closest to us

Quote Quote by jbobay2339 View Post
haha thanks that answered that as u can tell ive just started some reading and learning but i love this stuff
No problem
Chronos
#5
Feb23-12, 02:01 PM
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The 5.87 trillion miles ryan mentioned is for one light year, so the journey to gliese 581g at 11m/s will take about 340,000 years. The planet is about 3-4 earth masses and its diameter is estimated at 1.2 - 1.4 times that of earth. That gives it a mean density somewhat greater than earth, so it definitely looks like a rocky planet. Here is the paper purporting its existence http://arxiv.org/abs/1009.5733. Its existence has, however, been in dispute. See http://blogs.discovermagazine.com/ba...se-581g-exist/ for the juicy details [scientists version of a cat fight].
Ryan_m_b
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Feb23-12, 02:02 PM
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Quote Quote by Chronos View Post
The 5.87 trillion miles ryan mentioned is for one light year, so the journey to gliese 581g at 11m/s will take about 340,000 years.
Cheers for the catch, I forgot to put the two things I'd said together.
Radrook
#7
Feb23-12, 03:17 PM
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Quote Quote by jbobay2339 View Post
....so wouldn't time be going slower for someone traveling at that speed?


Not enough to make a noticeable difference. Even at velocities slightly greater than that it still

wouldn't amount to much. For example, at the 17 miles per second velocity toward Gliese,

time dilation would still not be noticeable. For every second we age on Earth, the crew would

age approx 12 nanoseconds or twelve billionths of a second less. On the Mir space station

with an approx orbital velocity of 4.7845581802275 miles per second, a crewmember

ages approx 3 nanoseconds, or three billionths of a second less for every second we age

on Earth,


BTW
Earth orbital velocity around our sun averages approx 18.5044 mi. per second,
or 29.783 kilometers per second.


C-ship: The Dilation of Time

http://www.fourmilab.ch/cship/timedial.html
Chalnoth
#8
Feb24-12, 04:07 AM
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This is why interstellar travel is only remotely reasonable if we can find a means to keep the ship accelerating continuously throughout the entire journey. That or commit ourselves to some extraordinarily long-term journeys.
Borek
#9
Feb24-12, 04:18 AM
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Quote Quote by Radrook View Post
Not enough to make a noticeable difference
12 nanoseconds
3 nanoseconds
Don't treat nanoseconds so lightly, you are wrong by just 60 ns and you stir up a havoc in the scientific community.
Chalnoth
#10
Feb24-12, 04:21 AM
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Quote Quote by Borek View Post
Don't treat nanoseconds so lightly, you are wrong by just 60 ns and you stir up a havoc in the scientific community.
Why would you post this?
Ryan_m_b
#11
Feb24-12, 04:59 AM
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Quote Quote by Borek View Post
Don't treat nanoseconds so lightly, you are wrong by just 60 ns and you stir up a havoc in the scientific community.
Lol!
Quote Quote by Chalnoth View Post
Why would you post this?
Perhaps because it was funny
Radrook
#12
Feb24-12, 09:29 AM
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Quote Quote by Chalnoth View Post
Why would you post this?
Just a joke. : )
cepheid
#13
Feb24-12, 09:54 AM
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Quote Quote by Radrook View Post
Actually, to be acceptable grammatically, it should read like this:

Don't treat nanoseconds so lightly[.]

As to why it is posted, others might speculate and uselessly chuckle. However, only the poster can really tell. As the comment stands unsubstantiated, it inevitably comes across as mere opinion. Perhaps the author might be kind enough to elaborate in order to help keep the thread on track.


Your post confuses me greatly, so I just have to ask: are you entirely unfamiliar with the concept of humour, and do you really not know what the 60 ns was in reference to? OR were you yourself just trying to make a joke as well? If the latter, I gotta say, you need to work on your material.
Radrook
#14
Feb24-12, 12:07 PM
P: 334
Quote Quote by cepheid View Post


Your post confuses me greatly, so I just have to ask: are you entirely unfamiliar with the concept of humour, and do you really not know what the 60 ns was in reference to? OR were you yourself just trying to make a joke as well? If the latter, I gotta say, you need to work on your material.

Perhaps you are right and I misunderstood the post.
My sincere apologies.
Radrook
#15
Feb24-12, 12:15 PM
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Quote Quote by Borek View Post
Don't treat nanoseconds so lightly, you are wrong by just 60 ns and you stir up a havoc in the scientific community.

You are 100% right! Even a nansecond is very important in science.
CaptFirePanda
#16
Feb24-12, 12:22 PM
P: 27
It was a reference to the 60 ηs "anomaly" detected in the travel time for a neutrino and the subsequent hoopla.
Radrook
#17
Feb24-12, 01:08 PM
P: 334
Quote Quote by CaptFirePanda View Post
It was a reference to the 60 ηs "anomaly" detected in the travel time for a neutrino and the subsequent hoopla.




Thanks for the info.
cepheid
#18
Feb24-12, 05:37 PM
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Also just for clarity, I was the one giving you a hard time, not Borek, who told the joke.

Sorry for giving you a hard time.


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