Universe

A:

Aurora Borealis occurs when materials from the surface of the Sun collide with the atmosphere of the Earth. Experts make predictions about the occurrence of Aurora Borealis based on events taking place on the Sun and the speed of matter being thrown from the Sun's surface. Aurora Borealis is visible in portions of the Northern Hemisphere, including Canada, Scandinavia, North America, Siberia and Northern Europe.

See Full Answer
Filed Under:
  • What Is the Temperature of a Black Hole?

    Q: What Is the Temperature of a Black Hole?

    A: According to NASA, the temperature of a black hole with the mass of the sun is only one ten-millionth of a degree over absolute zero. Scientists determine this by measuring the temperature of the radiation that comes from a black hole.
    See Full Answer
    Filed Under:
  • Why Do Some Stars Appear Brighter Than Others?

    Q: Why Do Some Stars Appear Brighter Than Others?

    A: The apparent brightness of a star viewed from Earth varies based both on the type of star and its distance from the planet. The apparent magnitude differs from a star's absolute magnitude, which describes its brightness from a set distance, rather than the varying distances of stars seen from Earth. The lower the apparent magnitude, the brighter the star is as seen from Earth.
    See Full Answer
    Filed Under:
  • What Are Some Facts About the Aurora Borealis?

    Q: What Are Some Facts About the Aurora Borealis?

    A: Aurora Borealis occurs when materials from the surface of the Sun collide with the atmosphere of the Earth. Experts make predictions about the occurrence of Aurora Borealis based on events taking place on the Sun and the speed of matter being thrown from the Sun's surface. Aurora Borealis is visible in portions of the Northern Hemisphere, including Canada, Scandinavia, North America, Siberia and Northern Europe.
    See Full Answer
    Filed Under:
  • Why Did People Once Believe That Earth Was the Center of the Universe?

    Q: Why Did People Once Believe That Earth Was the Center of the Universe?

    A: The belief of early astronomers that the Earth was the center of the universe stemmed from limited astronomical tools and geocentric attitudes. The Ptolemaic Model, developed around 100 A.D., presented the Earth-centered solar system in which most early Roman astronomers believed.
    See Full Answer
    Filed Under:
  • Do the Planets Travel Around the Sun in a Path Called an Orbit?

    Q: Do the Planets Travel Around the Sun in a Path Called an Orbit?

    A: Planets travel around the sun in paths called orbits. Each planet has its own orbit around the sun, and one orbit around the sun is called a year. All planets travel in the same direction around the sun.
    See Full Answer
    Filed Under:
  • Who Discovered the Planet Saturn?

    Q: Who Discovered the Planet Saturn?

    A: It is impossible to determine who discovered Saturn, as it is one of five planets that are visible without the aid of instruments. Saturn has been widely observed by people for thousands of years, although its unique and complex system of rings are only visible using a telescope.
    See Full Answer
    Filed Under:
  • What Happens After a Supernova?

    Q: What Happens After a Supernova?

    A: Depending on the size of the star before it explodes as a supernova, the core of the star either shrinks back into a tiny neutron star or becomes a black hole. If the star is only a few times bigger than the sun, the core becomes a tiny neutron star. If the star is much bigger than the sun, the chances of it becoming a black hole are much greater.
    See Full Answer
    Filed Under:
  • How Many Modern Constellations Are There?

    Q: How Many Modern Constellations Are There?

    A: As of 2014, there are 41 modern constellations, which are constellations added to the catalogue after 1600. Four of them, Carina, Puppis, Pyxis and Vela are derived from Argo, a constellation catalogued by Ptolemy.
    See Full Answer
    Filed Under:
  • Q: What Is the Function of the Solar Plexus?

    A: The solar plexus, or celiac plexus, is a large cluster of nerves that relay messages from the major organs of the abdomen to the brain. These organs, called visceral organs, are important to metabolism and to general life functioning. The solar plexus monitors them and makes sure they are functioning correctly.
    See Full Answer
    Filed Under:
  • Q: How Large Is the Universe?

    A: As of 2014, the size of the universe is unknown. Clues to its size can only be found within the limits of the observable universe, which is a sphere with a diameter of about 92 billion light-years.
    See Full Answer
    Filed Under:
  • Q: How Did the Universe Begin?

    A: The universe began with the Big Bang around 13.6 billion years ago. The Big Bang was a rapid expansion of the universe from a tiny single point. This hot expansion has continued since then, resulting in the expansion of the universe in every direction.
    See Full Answer
    Filed Under:
  • Q: What Is Beyond the Universe?

    A: It is impossible to know what lies beyond the universe. Our modern technology can only detect the light that has had the time to reach us, making it impossible to even estimate the size of our universe.
    See Full Answer
    Filed Under:
  • Q: How Do You Explain the Big Bang Theory to Kids?

    A: Explain the Big Bang Theory to kids using simple terminology and metaphors they can understand to help them relate the new concepts to concepts they already know. For example, remind them that one year is the amount of time it takes to get from one birthday to the next to help them understand just how long ago it was 14 billion years ago, when scientists believed the big bang occurred.
    See Full Answer
    Filed Under:
  • Q: How Does Gravity Affect the Earth?

    A: An important effect of gravity on the Earth is that the sun's gravity is responsible for the Earth's regular orbit through the solar system. The Earth travels at a velocity that approximates the force the sun exerts on the planet, resulting in a regular orbit. Without gravity, the planet would spin away into space, and if gravity was suddenly increased, it would eventually spiral into the star's fiery surface.
    See Full Answer
    Filed Under:
  • How Many Solar Systems Are There?

    Q: How Many Solar Systems Are There?

    A: The exact number of solar systems is not known. According to NASA, there are more than 100 billion galaxies within the universe. One of these galaxies is the Milky Way galaxy, where our solar system is located.
    See Full Answer
    Filed Under:
  • Q: What Did Nicolaus Copernicus Discover?

    A: Nicolaus Copernicus was a Polish scientist who is credited with the early 16th-century discovery that the sun is the center of the universe and that Earth and several other planets orbit it. Copernicus' discovery, which subsequent astronomers expanded on, has become known as the heliocentric solar system.
    See Full Answer
    Filed Under:
  • Q: Does the Universe End?

    A: Scientists believe the Universe is infinitely large and does not end. However, only part of the Universe is visible from Earth. The Observable Universe is a sphere around the Earth, and anything beyond this sphere cannot be observed from Earth because of continuing expansion over a long period of time.
    See Full Answer
    Filed Under:
  • Q: How Far Does Space Go?

    A: From Earth's surface, outer space begins at the somewhat-arbitrary Karman Line, or 100 km up, according to the Space website. From there, the observable universe stretches out without reaching any perceptible boundary.
    See Full Answer
    Filed Under:
  • Q: What Is Kepler's Universe Theory?

    A: Johannes Kepler's theories of the universe were notable for hypothesizing that the universe was created on April 27, 4977 B.C. and that the planets orbit in an elliptical pattern rather than a circular pattern. His theory superseded previous theories which postulated that planets move in circular orbits at constant speeds.
    See Full Answer
    Filed Under:
  • Q: What Is the Best Estimate Scientists Have Made of the Physical Size of the Universe?

    A: The best estimate of scientists trying to quantify the size of the universe place estimates on the observable portion at 46 billion light years from earth to the observable edge, or approximately 91 billion light years in diameter. However, there are some fundamental flaws with this approach.
    See Full Answer
    Filed Under:
  • Q: What Are the Differences Between the Solar System and the Milky Way Galaxy?

    A: The solar system is a system in the universe that is comprised of the Sun, eight official planets, three dwarf planets and approximately 130 satellites of the planets, according to Nine Planets. Besides these bodies, the solar system also has numerous comets and asteroids, which are smaller. On the other hand, the Milky Way is the galaxy within which the solar system falls.
    See Full Answer
    Filed Under: