Measuring Earth with a Stick Have you ever heard of the Greek mathematician and astronomer Eratosthenes? His name is probably best known among astronomers. Why do they think so highly of him? Eratosthenes was born about 276 B.C.E. and received some of his education in Athens‚ Greece. He spent a good part of his life‚ however‚ in Alexandria‚ Egypt‚ which at that time was under Greek rule. In about 200 B.C.E.‚ Eratosthenes set out to determine the dimensions of the earth by using a simple stick
Premium Sun Circle Solar System
head and a long tail. As a comet travels‚ it sheds bits of itself; from Earth‚ these are seen as showers of light called meteors. Astronomers would love to get a hold of a comet sample because it would be a piece of evidence from the birth of the Solar System. Comets have been observed and recorded for thousands of years but they have not always been understood. They were once called “hairy stars” and their sudden appearances made superstitious people regard them bad omens. People could only guess
Premium Planet Solar System Sun
Some say the New Moon even looks like a solar eclipse. Did you know‚ that Galileo lived to be almost 100 years old?! When the Sun moves‚ it covers some of the moon causing it to obtain a shadow. These shadows from the moon represent the illuminated side of the moon from the Sun. Sometimes the moon turns a deep shade of red. Although the moon could be a shade of red‚ it usually only happens during the eclipses. There are 4 different types of solar eclipses. They are the Partial Eclipse‚ the Annular
Premium Moon Earth Sun
encountered silicon-based lifeforms‚ but if they exist‚ they may have properties that have nothing in common with what we used to associate life with. According to another theory‚ life may be a rather common thing in the Universe; even in our Solar system at least several planets (Venus‚ Mars‚ Titan‚ Ganymede‚ Europa) in addition to Earth show signs of having atmosphere and in theory may host some primitive lifeforms. All in all‚ taking into account the vastness of Universe and the minuteness of
Premium Universe Solar System Life
uranus composition 82.5 percent hydrogen‚ 15.2 percent helium‚ 2.3 percent methane. Revolution The orbit of Uranus takes 84.3 year to complete one revolution around the Sun. In other words‚ 1 Uranian year is 84.3 Earth years. Special feauture Description Uranus was the first planet to be discovered in modern history. It was actually discovered by accident in 1781 by William Herschel. Like the other gas giants‚ Uranus has a very thick cloud cover and an atmosphere made up mostly of hydrogen
Premium Planet Jupiter Solar System
discovering a star. I say this‚ because you also have to have the orbital path calculated for a comet. This can take up to a year‚ because the proper orbit of a long-term cannot be calculated until it has gone out of the planetary regions of the solar system. While you may see a comet that has never been seen before‚ a lot more
Premium Solar System Planet Earth
Oxygen atmosphere‚ single celled aerobic organism. Achaean (3800-2500) Anaerobic bacterial life‚ oxygen starts to accumulate Experiments with bacteria start to occur within nature Create proton gradients Hadean (4600-3800 Ma) Formation of the solar system and planet‚ end with origins of life Fungi is the closest ancestor to us Slide 4 Major Era – Phanerozoic Cenozoic (65 Ma to present) Dinosaurs disappear‚ mammals and birds Mesozoic (251-65 Ma) Flowering plats‚ dinosaurs‚ even more insects Paleozoic
Premium Planet Water Bacteria
Why We Should Go to Mars Humans seem to have never stopped exploring the outer space since their inception. In 1969‚ astronauts landed on the moon‚ which represented a landmark in humans’ history. In similar fashion‚ humans intend to send a manned spacecraft to Mars. The mystery of Mars is always fascinating to humans on earth throughout the history. Some powerful nations are competing for space exploration‚ especially for a Mars mission. However‚ some people argue that a Mars mission is a considerable
Premium Space exploration NASA International Space Station
Space Radiation Too Deadly For Mars Mission by Charles Q. Choi‚ Special to SPACE.com Date: 31 March 2008 Time: 10:00 AM ET Dangerous levels of radiation in space could bar astronauts from a mission to Mars and limit prolonged activity on the moon‚ experts now caution.However‚ more research could reveal ways to handle the risks that radiation poses to space missions.The magnetic field of Earth protects humanity from radiation in space that can damage or kill cells. Once beyond this shield‚ people
Premium Space exploration NASA Mars
within science‚ but has the government been lying about life on Mars this whole time? Is there already human inhabitants on Mars creating a second Earth for when Earth is completely depleted of natural resources? Mars is the only planet in our Solar System‚ other than Earth‚ that can withhold life on the surface according to NASA. The theory started once NASA discovered the presence of water. Since the
Premium Mars Planet Solar System