Submitted to: Dr. Ravinder Aggrawal

Submitted by: Sarah Ali Hasan

Roll No. : 801251019

Date : Nov 19th 2013

One of the technical wonders of the modern world. Hubble Space

Telescope is an orbiting astronomical observatory operating from the

near-infrared into the ultraviolet.

350 miles above Earth, Hubble sees farther and sharper than any

previous telescope.

Its discoveries have revolutionized all areas of astronomy, has

imaged more than 30,000 celestial objects, snapping more than

570,000 pictures.

Overview :

• The reason Hubble is in orbit around the Earth, rather than on the

ground, is to get above the Earth’s atmosphere.

• Turbulence in the Earth’s atmosphere causes blurring of the images,

which is avoided when the telescope is above the atmosphere.

• Also the atmosphere absorbs some wavelengths of light, a

complication that is also avoided by being in orbit.

• Finally, some light is lost when it passes through the atmosphere. By

being in orbit above the atmosphere, Hubble avoids this light loss

and can see very faint objects.

• Hubble is a large astronomical telescope that was placed in orbit around Earth. It is about the size of a school bus and a mass of about 11,000 kg.

• Hubble is in a low-Earth orbit (so it can be serviced by the Space Shuttle).

• It Orbits the Earth about once every 96 minutes. Each orbit is about 1 hour in sunlight (orbit day) and 1/2 hour in darkness (orbit night).

• Hubble is designed to make observations of astronomical objects in visible light, near infrared, and near ultraviolet wavelengths—it can observe wavelengths in the range of 100–2500 nm. (Visible light lies within this range, from 400–700 nm.)

• Hubble is able to look deep into space; up to 14 billion light yearsaway!

Hubble's instruments:

No existence for eyepiece. Instead, the images observed by

Hubble are sent to a complement of scientific instruments

(cameras and spectrometers)). Each of which can perform its

own analysis and relay the resulting spectra and images to the

ground by radio.

Right from the very beginning the NASA/ESA Hubble Space Telescope

has been designed to be a new type of mission — a permanent

space-based observatory that could be regularly visited by the

Space Shuttle and serviced.

Present Instruments:

WFC3 - Wide Field Camera 3

COS - Cosmic Origins Spectrograph

ACS - Advanced Camera for Surveys (repaired during SM4)

STIS - Space Telescope Imaging Spectrograph (repaired during SM4)

NICMOS - Near Infrared Camera and Multi-object Spectrometer. (not currently

operational)

FGS - Fine Guidance Sensors

Former Instruments:

FOC - Faint Object Camera

WFPC2 - Wide Field and Planetary Camera 2

COSTAR - Corrective Optics Space Telescope Axial Replacement

WFPC1 - Wide Field and Planetary Camera 1

FOS - Faint Object Spectrograph

GHRS - Goddard High Resolution Spectrograph

HSP - High Speed Photometer

On board Hubble all the instruments are placed in the so-called

radial instrument bays and axial bays.

Four radial bays are placed around the sides of the telescope, and

are currently occupied by three Fine Guidance Sensors and the Wide

Field Camera 3 (WFC3). These instruments are shaped roughly like

quarter circles.

Four axial bays behind the mirror at the end of the telescope carry

rectangular box-shaped instruments. These bays are currently

occupied by the Cosmic Origins Spectrograph (COS), the Advanced

Camera for Surveys (ACS), the Space Telescope Imaging

Spectrograph (STIS) and the Near Infrared Camera and Multi-object

Spectrometer (NICMOS).

Hubble’s optics is all based on mirrors(no lenses); i.e. reflecting

telescope.

• Newtonian telescope → Cassegrain telescope → Ritchey-Chr´etien

Cassegrain design

Hubble’s primary mirror has a diameter of D=2.4 m (94.5 inches), &

has a focal length of: f =57.6 m. Another parameter often used to

characterize astronomical telescopes is the so-called f-number,

which is defined to be the ratio of the focal length to the

aperture diameter:

For Hubble, the primary mirror has an f-number of (f/24).

Resolution of an astronomical telescope is defined to be the smallest

angular separation of two point sources of light that will still allow

them to be resolved as individual point sources.

The exact point at which two adjacent diffraction patterns are

overlapping “too much” is a bit vague, but one commonly used

definition is the Rayleigh criterion.

Under the Rayleigh criterion, the smallest angular separation θ that

two point sources can have and still be resolvable as two individual

point sources is:

• Where θ is the angular resolution in radians, λ is the wavelength of

the light, and D is the diameter of the aperture of the instrument.

For the Hubble Space Telescope , D=2.4 m, and λ varies between

100 and 2500 nanometers. Using Rayleigh criterion, we can plot

the angular resolution of Hubble as a function of wavelength.

Hubble’s resolution in

visible light is about

0.05 arcseconds

(1 arcsec = 1/60 arcmint

= 1/3600 degree). This

means, if HST was in

Washington DC, it could

Distinguish 2 objects in

NY City if they were separated by a distance of just 3 inches:

Hubble’s Timeline

Edwin Hubble and the Hooker Telescope 1918 .

Conception of space telescope 1923 by Herman

Cberth.

The LST- Large Space Telescope 1969 by

suggested by Lyman Spitzer.

Congress Approves funding for The Hubble Space Telescope1977.

• 1978Astronauts begin training for space telescope missions

• 1979Work begins on the telescope’s 2.4-metre mirror

Space Telescope Science Institute (STScI) begins operations in Baltimore, Maryland 1981.

The Large Space Telescope is renamed Hubble 1983 , after Edwin P. Hubble, the astronomer who proved the existence of other galaxies and discovered the first evidence for an expanding universe.

Space Telescope-European Coordinating Facility (ST-ECF) begins operations in Garching, Munich1984.

Work on building Hubble is completed 1985.

Challenger disaster on 1986 puts all Shuttle flights

on hold Launch of Hubble delayed .

Launch: Shuttle Discovery (STS-31) launched on 24

April 1990. Hubble deployed on 25 April 1990.

-Spherical aberration discovered in the Hubble

primary mirror, 25 June 1990.

-COSTAR approved: The creation of a complex

package of five optical mirror pairs to rectify the

spherical aberration in Hubble's primary mirror.

First Servicing Mission (STS-61) launched on 2 December 1993 (Endeavour).

• COSTAR corrective optics installed, replacing HSP (High Speed Photometer).

• WFPC2 (Wide Field and Planetary Camera 2) replaced WFPC1 (Wide Field and Planetary Camera 1).

Hubble takes pictures of comet Shoemaker Levy 9 as it hits Jupiter in 1994.

Hubble takes the famous “pillars of creation” photo of the Eagle Nebula 1995.

The first Hubble Deep Field is released, showing the unimaginable number of galaxies in the Universe 1996.

• Hubble resolves quasar host galaxies.

Servicing Mission 2 (STS-82) launched on 11 February 1997 (Discovery).

• STIS (Space Telescope Imaging Spectrograph) replaced FOS (Faint Object Spectrograph).

• NICMOS (Near Infrared Camera and Multi-Object Spectrograph) replaces GHRS (Goddard High Resolution Spectrograph).

HST Orbital Systems Test (HOST - STS-95) launched on 29 October 1998 (Discovery). The HOST mission was flown to test new technologies to be used in Hubble on the Third Servicing Mission and beyond.

Servicing Mission 3A (STS-103) launched on 19 December 1999 (Discovery).

• Replacement of gyroscopes.

• General maintenance (no science instruments replaced).

Hubble observations detect the elements in the atmosphere of exoplanet HD 209458b in 2001.

Servicing Mission 3B launched on 1 March 2002.

• Installation of ACS.

• Installation of NICMOS Cooling System (NCS).

• Installation of new Solar Panels.

Power supply on STIS fails in 2004.

• Also Hubble Ultra Deep Field released.

Hubble images two previously unknown moons orbiting

Pluto in 2005.

Hubble observations show that the dwarf planet Eris is

bigger than Pluto in 2006.

The power supply on the Advanced Camera for

Surveys, one of Hubble’s key instruments, fails in

2007.

Hubble photographs exoplanet Fomalhaut b, one of the first to be confirmed through direct imaging in 2008.

• Hubble completes its 100,000th orbit around the Earth.

Servicing Mission 4 (STS-125) launched on 11 May 2009.

• Installation of WFC3 (Wide Field Camera 3).

• Installation of COS (Cosmic Origins Spectrograph).

• STIS and ACS repaired.

• Gyroscopes and batteries replaced.

• Soft Capture Mechanism installed.

• NOBLs (New Outer Blanket Layers) installed.

Hubble images show distant galaxies with likely red shifts greater than 8, showing the Universe as it was when it was less than a tenth of its current age in 2010.

History of the Universe revealed by Hubble

In 2011 Hubble makes its millionth observation,

a spectroscopic analysis of the exoplanet

HAT-P-7b .

10 000th scientific paper using Hubble data is

published, identifying the faintest

supernova ever to be associated with a long-

duration gamma-ray burst.

May 2012 witnessed the hit discovery of

NASA; four billion years from now: the next

major cosmic event to affect our galaxy,

sun, and solar system: the titanic collision

of our Milky Way galaxy with the

neighboring Andromeda galaxy.

• This illustration shows the collision paths of our Milky Way galaxy and the Andromeda galaxy. The galaxies are moving toward each other under the inexorable pull of gravity between them. Also shown is a smaller galaxy, Triangulum, which may be part of the smashup. (Credit: NASA; ESA; A. Feild and R. van der Marel, STScI).