• Do you believe science will eventually be able to explain every aspect of the universe?

    Best answer: If our species doesn't wipe itself out, yes. Look at the progress from horse and buggy to space shuttles and experimenting with trying to create wormholes in only 100 years time. Think about that. Horse and buggy to space shuttles... In 100 years. Sadly we can't get rid of religion, so the human race is... show more
    Best answer: If our species doesn't wipe itself out, yes. Look at the progress from horse and buggy to space shuttles and experimenting with trying to create wormholes in only 100 years time.

    Think about that. Horse and buggy to space shuttles... In 100 years.

    Sadly we can't get rid of religion, so the human race is likely to go extinct relatively soon.
    49 answers · 3 days ago
  • If the earth is round, then how come the moon doesn't circle around the earth?

    Best answer: You know what's funny? I've never had a flat Earther nor a creationist say checkmate to me. And Not just because they usually aren't very good at chess.
    Best answer: You know what's funny? I've never had a flat Earther nor a creationist say checkmate to me. And Not just because they usually aren't very good at chess.
    12 answers · 13 hours ago
  • Do you think humans can at the very least save life, in the long run?

    Clearly humans will never colonize other planets for obvious reasons. The energy required is probably just too great to even begin pondering. But at the very least, we could perhaps try to save earth life in SOME form by sending it (possibly microbes) to habitable planets. Do you think this is feasible, or will... show more
    Clearly humans will never colonize other planets for obvious reasons. The energy required is probably just too great to even begin pondering. But at the very least, we could perhaps try to save earth life in SOME form by sending it (possibly microbes) to habitable planets. Do you think this is feasible, or will earth life end in < 600 million years as the sun expands?
    7 answers · 19 hours ago
  • If the universe is 14 billion years old why is the observable universe 92 billion years across ?

    Best answer: Different sets of units. The furthest distance we can see directly is around 14 billion light-years in "look-back" distance. This is the manner in which astronomers normally measure distance: if the light takes a billion years to get here, then the distance is a billion light-years. Simple. And for short... show more
    Best answer: Different sets of units.

    The furthest distance we can see directly is around 14 billion light-years in "look-back" distance. This is the manner in which astronomers normally measure distance: if the light takes a billion years to get here, then the distance is a billion light-years.
    Simple.
    And for short distances, it works so well that the scale is used all the way "back" to the Cosmic Microwave Background radiation (roughly 13.8 billion light-years away, in all directions).

    HOWEVER
    when we look at some object located at a billion light-years (look-back) from us, we see it as it was and WHERE IT WAS a billion years ago.
    Because of the expansion of space itself, the amount of space between us and that object NOW, is a lot more than a billion light-years. If you could see the object where it is now, instead of where it was a billion years ago, you would be measuring its "comoving distance".

    In comoving distance, once you allow for (what we think is) the expansion rates of space over the last 14 billion years, then an object that we SEE at 13.8 billion light-years (look-back distance) is really around 46 billion light-years (comoving distance).
    Multiply by 2 to get the diameter and that is your "92 billion light-years across" (comoving).

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    A few added twists:
    Scientists were wondering if the universe was "small", even, possibly wrapped around something else - in another dimension - so that possibly we were looking part of the way around (like traveling 30,000 km one way, on Earth, instead of turning around and going only 10,000 km to reach the same point).
    Tests were designed and the apparatus was flown on a probe called WMAP.
    Results of the test show that not only the universe is not "small", but it is AT LEAST three times larger than the portion we can see. AT LEAST only sets a minimum. We do not know if there is a maximum, so that "infinite" is still possible, even if many would prefer that the universe not be infinite.
    So your "92 across" only applies to the Observable Universe. The whole universe is AT LEAST 276 billion light-years across, and could be a lot more. (yes, it could still be infinite, even if that displeases some that have pet theories requiring the universe to be finite).

    And there there is the apparent curvature problem. If you rune the expansion of space backwards, then as you go back in time, you should see distances get smaller between two points that are fixed in their local space.
    Look at the CMB radiation in one direction. 13.8 billion light-years away.
    Turn 180 degrees and look at the CMB radiation from the opposite direction. Also 13.8 billion light-years away.
    They appear to be 27.6 billion light-years apart from each other, right?
    Wrong.
    Back then (corresponding to the time we see them at) they were very close together.
    Spacetime is curved. But spacetime is just a model representing the fact that light is "slow" compared to the scale of the universe.
    When we go from "look-back" to comoving, we must also unravel that curve, since the universe appears flat (another test done by WMAP). This effect is included when we account for comoving distance.

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    Stand at the north pole. One friend goes along the Prime Meridian (longitude 0) and another friend goes down along longitude 180. After then have each gone 19,998 km, you think they are 39,996 km apart. In reality, they would be 4 km apart and probably can see each other (with binoculars). That is the "fun" part of measuring distances in a curved mathematical space (Earth's surface, in this case). Astronomers have to be careful of a similar effect when using look-back distances in the billions. For short distances, it is not a problem.
    13 answers · 2 days ago
  • Do you believe in UFOs?

    Best answer: I have seen one so want to know what and where they come they come from
    However we will never know as governments hide the truth
    Best answer: I have seen one so want to know what and where they come they come from
    However we will never know as governments hide the truth
    16 answers · 5 days ago
  • This one time, I saw a huge flash of light in the sky?

    Best answer: It was Flash Gordon streaking across the sky to save the world.
    You are a previliged observer.
    Best answer: It was Flash Gordon streaking across the sky to save the world.
    You are a previliged observer.
    14 answers · 3 days ago
  • If scientists aren't against the existence of extraterrestrials, how come they haven't found any evidence, they're not trying hard enough?

    Best answer: It's for the same reason we didn't know that Jupiter has moons, or that Venus has phases, until the telescope was invented. We haven't yet invented the tools we need to study the atmospheres of exoplanets, which is the likeliest way we'll find evidence of extraterrestrial life. We only just now (in... show more
    Best answer: It's for the same reason we didn't know that Jupiter has moons, or that Venus has phases, until the telescope was invented. We haven't yet invented the tools we need to study the atmospheres of exoplanets, which is the likeliest way we'll find evidence of extraterrestrial life. We only just now (in the last couple of decades) developed any way to confirm that exoplanets exist in the first place.
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    23 answers · 5 days ago
  • Is there a diameter earths solar system?

    14 answers · 4 days ago
  • Why can’t mainstream academia just accept the truth about so called “ancient aliens”?

    Basically, aliens who deserted whatever civilization they came from, came to earth (fallen angels) several thousand years ago, set up shop (one way trip), bred with early humans (elongated heads, not boarded) and built what’s now ruins (megaliths) and royal humans tried to mimic the look by wrapping and boarding... show more
    Basically, aliens who deserted whatever civilization they came from, came to earth (fallen angels) several thousand years ago, set up shop (one way trip), bred with early humans (elongated heads, not boarded) and built what’s now ruins (megaliths) and royal humans tried to mimic the look by wrapping and boarding their heads. Then the aliens former government caught up with them here and saw it all as an atrocity and wiped it out with a flood. Now, wasn’t that easy enough?
    21 answers · 5 days ago
  • What would happen to our measurements of star distances from us if we find that light slows down in the heliopause?

    Best answer: The impact on a lot of things we accept as proven would be disproven. A light year is a strange term because it references a given distance and time. Meaning there is a given conversion from light years to other means of measurement. If light either accelerates in free space or slows down because of long term... show more
    Best answer: The impact on a lot of things we accept as proven would be disproven.
    A light year is a strange term because it references a given distance and time. Meaning there is a given conversion from light years to other means of measurement.
    If light either accelerates in free space or slows down because of long term effects of magnetism or gravity, it would mean our ways of determining the age of the universe, direction of a stars movement and several other things is wrong.
    The speed of light is known to change depending on the medium, also that different energy levels travel at different speeds. That is why light can be refracted. But the differences in speed are considered so small they are seldom even mentioned in science courses.
    One of the interesting things is that there is a threshold that determines if light remains light. Below that speed it is no longer light. It becomes s different form of energy. That speed is very dependent on the medium. In all probability it does slow down at any change of medium. But it remains light. The impact on our measurements is dependent on the thickness of the material through which it passes. Given the thicknesses of the medium in proportion to the total distance- the effect would be negligible. Just to pop some easy numbers out-
    Total distance=100
    Distance in free space= 99.9
    Distance in heliopause= 00.1
    Of course the free space distance would be a greater amount.
    But this shows the over all impact to be less then 10%, while in reality the total impact would be less then 0.000000000000000000000000000000000001
    9 answers · 3 days ago
  • Which would draw more millionaire tourists, a hotel in earth orbit or a resort on the moon?

    Best answer: The orbital hotel would by definition draw more visitors, just like an airline hub has more traffic than destination airports, since it would undoubtedly be a way station on the way to the Moon. And since it will cost exponentially more for the lunar excursion, simple economics dictates that the orbital hotel will... show more
    Best answer: The orbital hotel would by definition draw more visitors, just like an airline hub has more traffic than destination airports, since it would undoubtedly be a way station on the way to the Moon. And since it will cost exponentially more for the lunar excursion, simple economics dictates that the orbital hotel will draw more visitors. If it costs $20 million to get to LEO, it's going to cost $200 million for the Moon.
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    5 answers · 22 hours ago