Studying The Universe

Artificial SatellitesArtificial satellites

are human-built objects orbiting the Earth and other planets in the Solar System.

 Artificial satellites are used to study the Earth, other planets, to help us communicate, and even to observe the distant Universe

Sputnik 1 was the first artificial satellite to be put into Earth's orbit. It was launched into an elliptical low Earth orbit by the Soviet Union on 4 October 1957. It was launched during the International Geophysical Year from Site No.1/5, at the 5thTyuratam range, in Kazakh SSR (now at the Baikonur Cosmodrome). The satellite travelled at 29,000 kilometers (18,000 mi) per hour, taking 96.2 minutes to complete an orbit, and emitted radio signals at 20.005 and 40.002 MHz .The signals continued for 22 days until the transmitter batteries ran out on 26 October 1957.Sputnik 1 burned up on 4 January 1958, as it fell from orbit upon reentering Earth's atmosphere, after travelling about 60 million km (37 million miles) and spending 3 months in orbit.

First Artificial Satellite in Space

Sputnik 1

Other Artificial SatellitesLuna 2 (E-1A series) was the second of the Soviet Union's Luna programme spacecraft launched to the Moon. It was the first spacecraft to reach the surface of the Moon. It successfully impacted with the lunar surface east of Mare Imbrium near the craters Aristides, Archimedes, and Autolycus. It is launched on September 12, 1959 at 06:39:42

Vanguard 1Vanguard 1 was the 4th artificial Earth satellite and first satellite to be solar powered. The spacecraft weights 1.47 kg. It is launched on March 17, 1958 at 12:15:41UTC. This holds record for being in space longer than any other man made objects

First Human in SpaceOn April 12,1961, Russian cosmonaut Yuri Gagarin became the first human in space, making a 108-minute orbital flight in his Vostok 1 spacecraft.

Alan Bartlett Shepard, Jr. was an American naval aviator, test pilot, flag officer, and NASA astronaut 1961 became the second person, and the first American on the surface of the moon,. This Mercury flight was designed to enter, but not to achieve orbit. He is the fifth person to walk on the Moon and the only Mercury Astronaut walked on the moon.

(Alan Shepard planting American Flag on Moon’s Surface.)

Apollo 11Apollo 11 was the

spaceflight which landed the first humans, Neil Armstrong and Edwin "Buzz" Aldrin, Jr, on Earth's Moon on July 20, 1969, at 20:17:39 UTC. The United States mission is considered the major accomplishment in the history of space exploration.

Space ProbesA space probe is a scientific space exploration

mission in which a spacecraft leaves Earth and explores space. It may approach the Moon, enter interplanetary, flyby or orbit other bodies, or approach interstellar space. Space probes are a form of robotic spacecraft .

Example of Space ProbesVoyager 1

Voyager 1 is a 733-kilogram probe launched on September 5, 1977. It is currently still operational, making it the longest-lasting mission of NASA. It is the farthest human-made object from the Earth. As of 2010,Voyager is over 17 tetrameters (1.7 x 1013 meters or 1.7 x 1010 kilometers), 10.5 million miles from the sun.

Mars Exploration RoverNASA's Mars

Exploration Rover Mission (MER) is an ongoing robotic space mission involving two rovers, Spirit and Opportunity exploring to planet Mars. It is sending of two rovers—MER-A Spirit and MER-B Opportunity to explore the Martian surface and geology.

Skylab Skylab was a

space station launched and operated by NASA, the space agency of the United States. Skylab orbited the Earth from 1973 to 1979, and included a workshop, a solar observatory, and other systems.

International Space StationThe International Space

Station (ISS) is a habitable

Artificial satellite in low Earth orbit. It follows the Salyut, Almaz, Skylab and Mir stations. The ISS is amodular structure whose first

component was launched in 1998. Like many artificial satellites, can be seen from Earth with naked eye

TheoriesBig Bang Theory-

It states that the Universe was once in an extremely hot and dense state which extend rapidly. The expansion caused the universe cool and resulted in its present continuously expanding state.

Steady State Theory In cosmology,

the Steady State theory (also known as the Infinite Universe theory or continuous creation) is a model developed in 1948 by Fred Hoyle, Thomas Gold, Hermann Bondi and others as an alternative to the Big Bang theory (known, usually, as the standard cosmological model). In steady state views, new matter is continuously created as the universe expands, so that the perfect cosmological principle is adhered to.