• Have you ever worked in NASA?

    9 answers · 6 hours ago
  • If humanity were to send two interstellar craft, one with the spin of the galaxy and the other against the spin would one get there faster?

    So say humanity builds two interstellar craft and there happens to be a star 5 lightyears away on either side of us, one ahead of us the way the galaxy is rotating and one behind us. Would the craft going against the rotation of the galaxy get there faster?
    So say humanity builds two interstellar craft and there happens to be a star 5 lightyears away on either side of us, one ahead of us the way the galaxy is rotating and one behind us. Would the craft going against the rotation of the galaxy get there faster?
    8 answers · 2 days ago
  • In my own opinion, NASA is slow, what do you say?

    I mean, why can't they go on space explorations to distant places just like in the movies? All they do is send space probes mostly.
    I mean, why can't they go on space explorations to distant places just like in the movies? All they do is send space probes mostly.
    27 answers · 3 days ago
  • Relativity has been proven right? So how come we don't see stars and planets aging faster than the rest of the cosmos?

    I mean...shouldn't something pop out at us as not being at the same speed as the rest on the universe...like that star trek episode
    I mean...shouldn't something pop out at us as not being at the same speed as the rest on the universe...like that star trek episode
    8 answers · 20 hours ago
  • Why isnt pluto a planet?

    Best answer: Pluto didn't pay its dues to join the big planet club.
    Best answer: Pluto didn't pay its dues to join the big planet club.
    21 answers · 4 days ago
  • Does Mars have a strong enough gravity to hold an Earth-type atmosphere?

    Best answer: Yes. The evidence for a history of large liquid water bodies on Mars suggests that it once had a much thicker atmosphere than it does today. The absence of a magnetic field makes Mars more vulnerable to the solar wind than the earth is, and even now, Mars loses atmosphere as the solar wind blows by. Another... show more
    Best answer: Yes. The evidence for a history of large liquid water bodies on Mars suggests that it once had a much thicker atmosphere than it does today. The absence of a magnetic field makes Mars more vulnerable to the solar wind than the earth is, and even now, Mars loses atmosphere as the solar wind blows by. Another possibility is that a large collision at some time in the past caused a severe and sudden depletion of the Martian atmosphere. It is true that gravity at the surface of Mars is less than 40% of what it is on earth, and this does allow individual molecules to reach escape velocity more easily than they do in the earth's atmosphere. However, Titan has much less gravity than Mars and yet retains a substantial atmosphere that exerts MORE pressure at Titan's surface than 1 earth atmosphere exerts. Part of the difference is that Titan's atmosphere is quite cold (as Titan is very far from the sun), so not many of its molecules are going fast enough to free themselves.

    The loss of the presumed thick ancient atmosphere of Mars is a research question that provokes new papers every year.
    26 answers · 5 days ago
  • Are the sun spots made of dark energy?

    13 answers · 3 days ago
  • Is 13.8 byrs really the age of the Universe since we are only guessing at the radius of the Universe?

    Best answer: Space expands everywhere (including inside individual photons of light). Over small distances, the rate of expansion is extremely small. However, over long distances, it adds up. Over a distance of one million parsec (1 Mpc = 3.26 million light-years), that rate amounts to approximately 70 km/s. Every second, the... show more
    Best answer: Space expands everywhere (including inside individual photons of light).
    Over small distances, the rate of expansion is extremely small.

    However, over long distances, it adds up. Over a distance of one million parsec (1 Mpc = 3.26 million light-years), that rate amounts to approximately 70 km/s. Every second, the amount of space between two objects separated by 1 Mpc increases by 70 km.

    The rate of change appears to be the same everywhere. 1 Mpc measured from Earth would expand at the same rate as 1 Mpc measured from Jupiter or from another galaxy.

    Now, apply the rate of expansion in reverse. A distance of 1 Mpc of space would decrease by 70 km every second. How long does it take to reach zero? Approximately 13.8 billion years.

    It does not matter what length you begin with.
    Over a distance of 1 light-year, the rate of expansion is only 2.1 cm per second. If you apply the same approach, how long would it take (in reverse) for that length of 1 light-year to reach zero if you decrease it by 2.1 cm every second? The same 13.8 billion years.

    The reason that we say the radius of the Observable Universe** is 13.8 billion light-years is connected. If you apply this rate of change (70 km/s for each Mpc), you find that at a distance of 13.8 billion light-years, the rate of expansion is equal to the speed of light... and it is impossible for us to see anything that would be further out (the light from it would never be able to reach us, since the amount of space left to travel would increase faster than the light can move). Thus, calculating the radius of the Observable Universe comes AFTER we calculate the age. We do not need it for the calculation of the age.
    Both the age and the radius can be calculated directly from the rate of expansion of space (plus other things used to apply corrections that give us a more precise value -- we know that the rate does change over time).

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    **The Observable Universe is the portion we can perceive. The whole universe seems to be bigger than that, and we do not know its actual size.
    7 answers · 1 day ago
  • Is there life on Europa?

    Best answer: Probably not, but obviously no one knows. Other worlds like Enceladus also hold exciting prospects for extraterrestrial life; there may be liquid oceans on Ceres and Ganymede as well.
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    If we ever discover extraterrestrial life, you won't have to ask about it here.
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    Best answer: Probably not, but obviously no one knows. Other worlds like Enceladus also hold exciting prospects for extraterrestrial life; there may be liquid oceans on Ceres and Ganymede as well.
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    If we ever discover extraterrestrial life, you won't have to ask about it here.
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    11 answers · 3 days ago
  • What is difference universe and earth?

    Best answer: Imagine a single hair on your head. Now compare that to the whole bodies of every person on Earth. That is like comparing Earth to the universe, but even more.
    Best answer: Imagine a single hair on your head. Now compare that to the whole bodies of every person on Earth. That is like comparing Earth to the universe, but even more.
    9 answers · 3 days ago