Where can you find the Big Dipper in the evening sky?
The Big Dipper consists of the seven brightest stars in the constellation Ursa Major, also called the Big Bear. In the Northern Hemisphere, the Big Dipper appears in the northern sky, with its position and its orientation changing through the seasons of the year. In the fall and winter, it sets low, nearer the horizon; in the spring and summer, it appears higher in the sky. In the summer, the Big Dipper’s “bowl” faces downward, whereas it points upward in the winter. In summer and fall, the Big Dipper orients vertically, with the bowl facing east in the summer and west in the winter.
How many stars are there in our galaxy?
Scientists estimate that the Milky Way includes approximately 100 billion stars. No one has the time or the telescopic equipment necessary to count the Milky Way the way you would count the lights on a Christmas tree, but astronomers can use the amount of light each star emits, along with the mass of the stars, to figure out how to survey the cosmos. Of course, any such number constitutes an approximation, partially because what you see in the sky represents light that left the star millions or even billions of years ago, during which time that star may have ceased to exist.
What is a black hole?
Black holes come in three kinds. Primordial black holes likely date back to the formation of the universe, shortly after the big bang that created it. These black holes measure the size of a single atom with the mass of a mountain. Stellar black holes result from the death of a large star that collapses, creating a supernova or explosion. These black holes feature a diameter of about 10 miles with a mass 20 times that of the star in our own solar system. Supermassive black holes come into existence during the formation of a galaxy. Within a spherical area equivalent to the diameter of our galaxy, a supermassive black hole packs the mass of 1 million suns.
How hot is The Sun?
The star that gives life to our Earth consists of a nuclear power plant with a surface temperature of 10,000 degrees Fahrenheit. If you could travel into the core of the sun, you’d see the temperature rise the farther you went, all the way to more than 27 million degrees at the center. The sun’s surface, also called the photosphere, produces the energy we see as sunlight. The chromosphere, which looks like a rind of red outlining the sun during a solar eclipse, measures cooler than the surface at about 7,800 degrees Fahrenheit. The corona, in which plasma energy streams out beyond the surface and the chromosphere, measures about 3.5 million degrees Fahrenheit.
How long would it take to travel to Pluto?
The distance between the Earth and Pluto averages just over 3.5 billion miles, although it varies depending on where each of these two heavenly bodies lies along its orbit. Light arrives at Pluto from Earth in 4.6 hours. The New Horizons research probe left Earth on January 19, 2006, and arrived closest to Pluto on July 14, 2015, traveling between approximately 42,250 and 51,574 miles per hour. The Space Shuttles, which orbited the Earth at 17,500 miles per hour, would travel for 8,500 days to reach Pluto from Earth.
How do you locate the North Star?
Unlike other stars, the North Star, formally called Polaris, shows up in the same position during all four seasons of the year. Located in the constellation Ursa Minor, or Little Bear, Polaris appears farther north in northern latitudes and directly overhead at the North Pole. In the Southern Hemisphere, the North Star disappears below the horizon.