Man Made Satellites

                                                        Man Made Satellites

    Chandrayaan-1

  

 It was the first lunar probe under Chandrayaan  program .It was launched by the Indian Space Research Organization in October 2008, and operated until August 2009. The mission launch included a lunar orbiter and an impactor. India launched the spacecraft using a PSLV-XL rocket on 22 October 2008 at 00:52 UTC from Satish Dhawan Space Centre at Sriharikota , Andhra Pradesh. The mission was a major boost to India's space program, as India researched and developed its own technology to explore the Moon. The vehicle was inserted into Lunar orbit on 8 November 2008. It was intended to survey the Lunar surface over a two year period , to produce a complete map of the composition at the surface and three dimensional topography . The polar region are of special interest as they might contain water ice. The mass of the this during the launch was 1,380 kg (3,042 lb) and was 675 kg (1,448 lb) at the lunar orbit and was 523 kg (1,153 lb ) after releasing the impactor . During the tenure Prime Manmohan Singh Chandrayaan project got a boost and Chandrayaan-1 was launched . The Chandrayaan-1 payload has enabled scientists to study the interaction between the solar wind and planetary body like the Moon without a magnetic field .

Chandrayaan-2 

It was the the second lunar exploration mission developed by the Indian Space Research Organization (ISRO) it consisted of a lunar orbiter , and also included the Vikram lander, and  the Pragyan lunar rover, all of which were developed in India . The main scientific objective is to map and study the variations in lunar surface composition , as  well as the location and abundance of lunar water .The spacecraft was launched on its mission to the Moon from the second launch pad at the Satish Dhawan Space Centre in Andhra Pradesh on 22 July 2019 at 2.43 p.m. IST (09:13 UTC) by a GSLV Mark III M1. The craft reached the Moon's orbit on 20 August 2019 and began orbital positioning manoeuvres for the landing of the Vikram lander . The lander and the rover were scheduled to land on the near side of the Moon, in the south polar region at a latitude of about 70 degree south on 6 September 2019 and conduct scientific experiments for one Lunar day , which approximates to two Earth weeks. The primary objectives of the Chandrayaan-2 lander were to demonstrate the ability to soft-land and operate a robotic rover on the Lunar surface. 

Voyager 1

 Voyager-1 is a space probe that was launched by NASA on September 5 ,1977.  Objective of the Voyager program is to study the outer Solar System , Voyager 1 was launched 16 days after its twin, Voyager 2 . Having operated for 43 years , 4 months , and 11 days , the Space craft still communicates with the Deep Space Network to receive routine commands and to transmit data to Earth . At a distance of 152.2 AU ( 22.8 billion km , 14.1 billion mi ) from Earth . It is the most distant human-made object from Earth. Its objectives included the flybys of Jupiter , Saturn , and Saturn's largest moon , Titan. As a part of Voyager program the Space Craft is an extended mission to locate and study the region and  boundaries of the outer heliosphere and to begin exploring the interstellar medium . Voyager 1 crossed the heliopause and entered interstellar space on August 25 ,2012 , making it the first spacecraft to do so . Voyager 1 carries a copy of the Golden record - a message from humanity to the cosmos that includes greetings in 55 languages , pictures of people and places on Earth and music. 

   

Voyager 2 

Voyager 2 is a space probe launched by NASA on August 20 ,1977 , to study the outer planets . It was launched 16 days before its twin , Voyager 1 , on a trajectory that took longer to reach Jupiter and Saturn but  enabled further encounters with Uranus and Neptune. It is the only spacecraft to have visited either these two ice giant planets . Voyager 2 is the fourth of five spacecraft to achieve the Solar escape velocity. Its primary mission ended with the exploration of the Neptunian system on October 2, 1989 . Its extended mission to study interstellar Space has been operating for 43 years , 4 months and 26 days . It remains in contact through the NASA Deep Space Network. Voyager 2 has begun to provide the first direct measurements of the Density and temperature of the interstellar plasma. Each of the two spacecraft was equipped with a slow scan color TV camera take images of the planets and their moons and each also carried an extensive suite of instruments to record magnetic, atmospheric , lunar , and other data about planetary systems.

 

Sputnik 1

Sputnik 1 was the first artificial Earth satellite . The Soviet Union launched it into an elliptical low Earth orbit on 4 October 1957. It was polished metal sphere 58 cm (23in) in diameter with four external radio antennas to broadcast radio pulses. Its radio signal was easily detectable by radio amateurs , and 65 degree inclination and duration of its orbit made its flight path cover virtually the entire inhabited Earth. Tracking and studying Sputnik 1 from Earth provided scientist with valuable information. The satellite travelled at about 29,000 kilometers per hour (18,000 mph; 8100m/s), taking 96.2 minutes to complete each orbit. It transmitted on 20.005 and 40.002 MHz, which were monitored by radio operators throughout the world. The signal continued for 21 days until the transmitter batteries ran out on 26 October 1957. The control system of the Sputnik rocket was adjusted to an intended orbit of 223 by 1,450 km (139 by 901 mi) , with an orbital period of 101.5 min. Sputnik 1 burned up on 4 January 1958 while reentering Earth's atmosphere after three months , 1440 completed orbits of the Earth, and a distance travelled of about 70 million km(43million mi).

Sputnik 2

  Sputnik 2 was the second spacecraft launched into Earth orbit , on 3 November 1957 , and the first to carry a living animal , a Soviet space dog named Laika . Launched  by the U.S.S.R. , Sputnik 2 was a 4-metre high (13ft) cone shaped capsule with a base diameter of 2 meters(6.6ft) that weighted around 500 kilogram (1,000lb), though it was not designed to separate from the rocket core that brought it to orbit, bringing the total mass in orbit to 7.79 tonnes ( 172,00lb). It contained several compartments for radio transmitters , a telemetry system , a programming unit, a regeneration and temperature-control system for the cabin, and scientific instruments. A separate sealed cabin contained the dog Laika .

International Space Station

The International Space Station (ISS) is a modular space station ( habitable artificial satellite ) in low Earth orbit . It is a multinational collaborative project involving five participating space agencies : NASA ( United States) , Roscosmos ( Russia ) , JAXA ( Japan) , ESA ( Europe), and CSA ( Canada).  The ownership and use of the space station is established by intergovernmental treaties and agreements . The station serves microgravity and space environment research laboratory in which  scientific research is conducted in astrobiology , astronomy, meteorology , physics , and other fields. The ISS is suited for testing the spacecraft systems and equipment required for possible future  long-duration missions to the Moon and Mars. It is the largest artificial satellite in space and the largest satellite in low Earth orbit , regularly visible by naked eye from Earth's surface . It maintains an orbit with an average altitude of 400 kilometers (250mi) . The station is divide into two sections: the Russian Orbital Segment ( ROS ) , operated by Russia ; and the United States Orbital Segment (USOS) , which is shared by many nations .