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HUBBLE SPACE TELESCOPE. -Presented by Kadhiravan D. About Hubble. Hubble Space Telescope was named after the scientist Edwin P.Hubble .It was he who first Confirmed the Big Bang Theory. Hubble was launched on 24 th April 1990 into space.
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HUBBLE SPACE TELESCOPE -Presented by Kadhiravan D
About Hubble • Hubble Space Telescope was named after the scientist Edwin P.Hubble .It was he who first Confirmed the Big Bang Theory. • Hubble was launched on 24th April 1990 into space. • Launched by: NASA with co-operation of ESA.
Why a Space Telescope? • Curiosity to explore the unknown. • Why not from the Earth but in Space? • It is the atmosphere partially blocks or absorbs certain wavelengths of radiation, like ultraviolet, gamma- and X-rays, before they can reach Earth. • These rays are also needed for a complete examination.
PowerNeeds Energy Source: The Sun Mechanism: Two 25-foot solar panels Power usage: 2,800 watts PowerStorageBatteries: 6 nickel-hydrogen (NiH) Storage Capacity: equal to 20 car batteries (7 hour backup capacity under the absence of sun Hubble Facts • SizeLength: 13.2 mWeight: 11,110 kg Maximum Diameter: 4.2 m • Cost at Launch$1.5 billion
Hubble Facts • Spaceflight Statistics • Orbit: At an altitude of 307 nautical miles (569 km, or 353 miles), inclined 28.5 degrees to the equator (low-Earth orbit) • Orbital Period: 97 minutes • Speed: 17,500 mph (28,000 kph) • Optical Capabilities • Sensitivity to Light: UV through IR (115—2500 nm) • Pointing Accuracy: 7/1000th of an arc second • Limitation: Direct view towards sun
Data Statistics • Hubble transmits about 120 gigabytes of science data every week. • That's equal to about 3,600 feet (1,097 meters) of books on a shelf. • The rapidly growing collection of pictures and data is stored on magneto-optical disks.
The Telescope • Primary Mirror Diameter: 94.5 in (2.4 m) Primary Mirror Weight: 1,825 lb (828 kg) Secondary Mirror Diameter: 12 in (0.3 m) Secondary Mirror Weight: 27.4 lb (12.3 kg) • Hubble is a type of telescope known as a Cassegrain reflector. • Collecting more light than the human eye can capture on its own.
Optical System • The optical telescope assembly consists of two mirrors, support trusses, and the apertures (openings) of the instruments. • System is a design known as Ritchey-Chretien Cassegrain.
Aluminum Shell Housing MLI-Multi-Layer Insulation Support Truss (Graphite Epoxy)
Science Instruments • Wide Field Camera 3 - (WFC3) • Cosmic Origins Spectrograph – (COS) • Advanced Camera for Surveys – (ACS) • Near Infrared Camera and Multi-Object Spectrometer – (NICMOS) • Space Telescope Imaging Spectrograph – (STIS) • Fine Guidance Sensors – (FGS)
Wide Field Camera 3 (WFC3) • Sees three different kinds of light • Near-ultraviolet, Visible and Near-infrared • Resolution and field of view are much greater than that of Hubble's other instruments. • Study dark energy and dark matter, the formation of individual stars and the discovery of extremely remote galaxies previously beyond Hubble's vision.
Cosmic Origins Spectrograph (COS) • Sees exclusively in ultraviolet light • Spectrographs acts something like prisms, separating light • This provides a wavelength "fingerprint" of the object being observed • About its temperature, chemical composition, density, and motion • Sensitivity at least 10 times, and up to 70 times
Advanced Camera for Surveys (ACS) • Sees visible light • Study some of the earliest activity in the universe • Helps map the distribution of dark matter, detects the most distant objects in the universe • ACS partially stopped working in 2007 due to an electrical short, but was repaired during Servicing Mission 4 in May 2009
Space Telescope Imaging Spectrograph (STIS) • Sees ultraviolet, visible and near-infrared light • Ability to hunt black holes • STIS stopped working due to a technical failure on August 3, 2004, but was also repaired during Servicing Mission 4
Near Infrared Camera and Multi-Object Spectrometer (NICMOS) • Hubble's heat sensor. • Its sensitive to infrared light. • Observe objects hidden by interstellar dust, like stellar birth sites, and gaze into deepest space.
Fine Guidance Sensors (FGS) • Devices that lock onto "guide stars" • Keep Hubble pointed in the right direction. • They can be used to precisely measure the distance between stars, and their relative motions.
Communication System • HST has 6 antennas and communicates through the TDRS system • TDRS- Tracking and Data Relay Satellites • The communications systems on the TDRS satellites were designed to support multiple missions at the same time. Each satellite has S band, Ku band (1st Gen only) and Ka band (2nd gen only) systems which support multiple data-rates • 10 launched 9 still in service; HST use 5 of them for communication to Earth.
Communication System • Frequency range lies in the C band ;Uplink Frequency – 6GHz; Downlink Frequency – 4GHz • 4 parabolic antennae in use; 2 antennae are backup • 2 Main Frame computers • Computer 1-Control the steering • Computer 2-Handles the data transmission and reception • The higher frequency is used for the up-link because the satellite antenna has limited size and a higher noise temperature (usually 290K). • The gain is higher at the upper frequency for a fixed antenna size.
Communication when Earth station is visible Earth Station Receiver Uplink Frequency6GHz Downlink Frequency4GHz H.S.T
TDRS System. Space Telescope Science Institute. H.S.T
Data Received • Recorded in 5.25 inch Magneto Optical Disk 2.6GB • Recorded data equivalent to 18 DVDs per week. • Astronomers can Download the archived data via Internet and analyze it.
Positioning System • Has 6 gyroscope of which 4 functional (3 needed 1 backup). • Has 3 Fine Guidance System (FGS) which help stabilize the telescope using vision. • Uses Reaction Wheels to steer.
Hubble’s Achievements • Hubble’s telescope is regarded as one of the most important instrument ever made. • Took hundreds of thousands of pictures of our universe. • The instruments can capture light that began traveling some 14 billion years ago. • It's helped astronomers determine that the age of the universe • Aged more than it was expected.
Hubble’s Achievements • Hubble was made with intension of running for 15years (till 2005);its life was extended till 2010. • Hubble has only a 50/50 chance of surviving another three and a half years since the last service was cancelled.
Hubble's Successor • The JAMES WEBB SPACE TELESCOPE which will be designed to view objects in visible light and infrared, and its mirror will have six times the area of Hubble's mirror. • JWST will carry a NICMOS and a mid-infrared camera. • JWST's working location is 1.5 million kilometers out in space - stationed at L2 • The JWST IS BILLED $824.8 million. • the JWST is outfitted with a large sunshade. • JWST is expected to see objects 400 times fainter.
EAGLE NEBULA CONE NEBULA WHIRLPOOL GALAXY THE CATS EYE NEBULA JUPITER THE MICE
References • www.hubblesite.org • www.howstuffworks.com • www.wikipedia.org