JAMES WEBB SPACE TELESCOPE
-
Upload
sreeja-nettath -
Category
Engineering
-
view
106 -
download
7
Transcript of JAMES WEBB SPACE TELESCOPE
JAMES WEBB SPACE TELESCOPE
PRESENTED BYSREEJA NEEE 8th SEMRGIT
CONTENTS
Introduction
History
Construction and Working
Launch of JWST
Advantages
Disadvantages
Conclusion
Reference
INTRODUCTIONIt is also called WEBB or JWST.
It is a large space based observatory telescope.
Is optimized for infrared wavelengths.
Include answering some of our most fundamental questions about the origin of the cosmos.
It will be located near the
Earth–Sun L2 point.
It is 1,500,000 kilometers
(930,000 mi) from Earth,
directly opposite to the Sun.
L2 point the combined
gravitational pull of the
Earth and the Sun .
HISTORYThis space-based observatory is named after James E.
Webb (1906- 1992).
The project represents an international collaboration of about 17 countries.
The JWST originated in 1996 as the Next Generation Space Telescope (NGST).
Launch is scheduled for 2018 on an Ariane 5 rocket. Its nominal mission length is of five years.
It is successor to NASA's Hubble Space Telescope.
CONSTRUCTION AND WORKINGIt will be the largest space telescope.
It has four main element
the telescope.
the instrument module(ISIM) .
the sunshield .
the spacecraft bus.
PRIMARY MIRROR
It consists of 18 individual hexagonal mirror(6.8mtr die).
The mirror segments is made of beryllium.
The mirrors are build in segments on a structure, which will fold up, so that it can fit into a rocket.
The mirror segments deploy and get aligned in space by
commands from Earth.
It can gather more light and resolve more details.
The hexagonal shape allows a segmented mirror with high
filling factor
Webb needs to be very cold ("cryogenic"), with its mirrors
at around -220 degrees C
SECONDARY AND TERTIARY MIRROR The single secondary mirror is perfectly rounded and
convex
The tertiary mirror is the third stop for light coming into the telescope and is the only fixed mirror in the system
The light from an object reflects off the mirrors before entering the science instruments in the back of the telescope
SUNSHIELDThe JWST must be kept very
cold (under 50 K (−220 °C; −370 °F))
It uses a large sunshield to block light and heat from the Sun, Earth, and Moon
L2 point keeps all three bodies on the same side of the spacecraft at all times.
Maintains a constant environment for the sunshield and solar arrays.
The sunshield is made of polyimide film, has membranes
coated with aluminum on one side and silicon on the other
side
It is designed to be folded twelve times so it will fit within
the Ariane 5 rocket
The sunshield was hand-assembled at Man Tech Albama
It is approximately tennis court-sized five-layer deployable
sunshield.
ISIM(Integrated Science Instrument Module )
The ISIM is the heart of the James Webb Space Telescope
This is the unit that will house the four main instruments that will detect light from distant stars and galaxies
Near-Infrared Camera
Near-Infrared Spectrograph
Mid-Infrared Instrument
Fine Guidance Sensor/ Near InfraRed Imager and Slitless Spectrograph
Near-Infrared Camera
NIRCam will detect light from the
earliest stars
NIRCam is equipped with
coronagraph
will cover the infrared wavelength
range 0.6 to 5 microns.
Near Infrared SpectrographIt is being built by the European
Space Agency
Analyzing the spectrum of an
object can tell us about its
physical properties
Multi-object capability
Micro shutter system to control
how light enters the NIRSpec.
Mid-Infrared InstrumentMIRI covers the wavelength range of 5 to 28
microns.
Its sensitive detectors will allow it to see the
redshifted light of distant galaxies, newly
forming stars, and faintly visible comets .
The Mid-Infrared Instrument (MIRI) has
both a camera and a spectrograph
Fine Guidance Sensor It has a wavelength range of 0.8 to 5.0
microns
It is a "guider," which helps point the
telescope.
The Spacecraft BusThe spacecraft bus provides the
necessary support for the operation
The bus is the home for six major subsystems:
Electrical Power Subsystem
Attitude Control Subsystem
Communication Subsystem
Command and Data Handling subsystem
Propulsion Subsystem
Thermal Control Subsystem
ADVANTAGES
infrared light emitted by these regions can penetrate this dusty cloud and reveal what is inside.
JWST will offer unprecedented resolution and sensitivity from long-wavelength visible to the mid-infrared
Understands the formation of stars and planets.
DISADVANTAGES
James Webb telescope so far from the Earth.
EAGLE NEBULA
SUPERNOVA
CONCLUSION
James webb space telescope capabilities will enable a
broad range of investigations across the fields
of astronomy and cosmology. It observes some of the
most distant objects in the Universe, beyond the reach
of current ground and space based instruments
REFERENCEhttp://www.jwst.nasa.gov
The Scientific Capabilities of the James Webb Space Telescope – Jon Gardner
Comparative Planetology: Transiting Exoplanet Science with JWST – Mark Clampin
Planetary Systems and Star Formation with JWST –George Rieke
Study of Planetary Systems and Solar System Objects with JWST – George Sonneborn