iPedia Free Information Center

Information about Herschel Space Observatory

This article is about the future ESA space telescope. For the telescope on the Canary Islands, see William Herschel Telescope


Herschel Space Observatory

Artist's impression of the Herschel Space Observatory
General information
Alternative names:Far Infrared and Submillimetre Telescope (FIRST)
Organization:ESA
Launched:July 2008 (delayed from July 2007
Deorbited:2010 - 2011
Mass:3,300 kg
Orbit height:1.5×106km from Earth
(L2 Lagrangian point)
Orbit period:1 year
Orbit velocity:7,500 m/s, 16,800  (0 )
Type of orbit:Lissajous orbit
Telescope style:Cassegrain reflector
Wavelength:infrared: 60 to 670 µm
Diameter:3500 mm, f/0.5
Collecting area:9.6 m²
Focal length:27000 mm
Instruments
HIFI:Heterodyne Instrument for the Far Infrared
PACS:Photodetector Array Camera and Spectrometer
SPIRE:Spectral and Photometric Imaging Receiver
 
Website:[1]


The Herschel Space Observatory is a mission of the European Space Agency. It is to be launched in 2008 aboard an Ariane 5 rocket together with Planck and will enter a 700,000 km diameter Lissajous orbit around the second Lagrangian point of the Earth-Sun system, 1.5 million kilometres away from Earth.<ref name = "FACT" /> The mission is named after Sir William Herschel, who discovered the infrared spectrum.[1]

Instrument

The mission, formerly titled the Far Infrared and Sub-millimetre Telescope (or FIRST),[2] will be the first space observatory to cover the full far infrared and submillimetre waveband, and its telescope will have the largest mirror ever deployed in space (three and a half metres wide).[3] The light will be focused onto three instruments with detectors kept at temperatures below 2 K. The instruments will be cooled with liquid Helium, boiling away in near vacuum at a temperature of ~1.4 K. The (operational) lifetime is limited by the amount of Helium on board the satellite.

The three detectors on board Herschel will be:[4]
  • PACS (Photodetecting Array Camera and Spectrometer) will be an imaging camera and low resolution spectrometer with coverage from 55 to 210 micrometres. The spectrometer will have a resolution between 1000 and 5000 and be able to detect signals as weak as a few times 10-18 W/m². The imaging camera will be able to image simultaneously in two bands (either 60-85 micrometres or 85-130 micrometres, as well as 130-210 micrometres) with a detection limit of a few millijanskies.[5]
  • SPIRE (Spectral and Photometric Imaging Receiver) will be an imaging camera and low resolution spectrometer with coverage from 194 to 672 micrometres. The spectrometer will have a resolution between 40 and 1000 at wavelengths of 250 micrometres and be able to image point sources with brightnesses around 100 millijanskies and extended sources with brightnesses of around 500 millijanskies.[6] The imaging camera has three bands, centered at 250, 350 and 500 micrometres, which have 139, 88 and 43 pixels respectively. The imaging camera can detect point sources with brightness above 2 millijanskies and for extended sources the threshold is between 4 and 9 millijanskies.
  • HIFI (Heterodyne Instrument for the Far Infrared) will be a high resolution spectrograph. The spectrometer has a resolution as high as 107.[7] The spectrograph covers two wavelength bands, from 157 to 212 micrometres and from 240 - 625 micrometres.

Science

Herschel will specialise in collecting light from objects in our solar system as well as further into the Milky Way and even extragalactic objects, such as newborn galaxies billions of light-years away.

The science goals of Herschel are<ref name = "SNT" />:

References

1. ^ Herschel Factsheet (1 February 2007). Retrieved on 2007-09-29.
2. ^ Herschel. European Space Agency Science & Technology. Retrieved on 2007-09-29.
3. ^ Herschel Space Observatory. Imperial College. Retrieved on 2007-09-29.
4. ^ Herschel. European Space Agency. Retrieved on 2007-09-29.
5. ^ PACS - Photodetector Array Camera and Spectrometer. Retrieved on 2007-09-29.
6. ^ SPIRE - Spectral and Photometric Imaging Receiver. European Space Agency. Retrieved on 2007-09-29.
7. ^ HIFI - Heterodyne Instrument for the Far Infrared. European Space Agency. Retrieved on 2007-09-29.

External links

European Space Agency (ESA), established in 1974, is an inter-governmental organisation dedicated to the exploration of space, currently with 17 member states. Its headquarters are in Paris.
..... Click the link for more information.
space observatory is any instrument in outer space which is used for observation of distant planets, galaxies, and other outer space objects.

Introduction

A large number of observatories have been launched into orbit, and most of them have greatly enhanced our knowledge of
..... Click the link for more information.
Comunidad Autónoma de Canarias
Autonomous Community of the Canary Islands

Flag Coat of arms

Anthem: Arrorró
Capital Las Palmas de Gran Canaria and
Santa Cruz de Tenerife
Official language(s) Spanish
Area
..... Click the link for more information.
William Herschel Telescope

Moonrise over the William Herschel Telescope
Organization: Isaac Newton Group of Telescopes
Location: Roque de los Muchachos Observatory, La Palma, Canary Islands
Wavelength: Optical / infrared
Built: Completed June 1 1987
..... Click the link for more information.
European Space Agency (ESA), established in 1974, is an inter-governmental organisation dedicated to the exploration of space, currently with 17 member states. Its headquarters are in Paris.
..... Click the link for more information.
Lagrangian points (pronounced [ləˈgɹɒɲ.dʒi.ən] or [laˈgʀɑ̃.
..... Click the link for more information.
Metre per second (U.S. spelling: meter per second) is an SI derived unit of both speed (scalar) and velocity (vector quantity which specifies both magnitude and a specific direction), defined by distance in metres divided by time in seconds.
..... Click the link for more information.
In orbital mechanics, a Lissajous orbit is a quasi-periodic orbital trajectory that an object can follow around a collinear libration point of a two-body system without requiring any propulsion.
..... Click the link for more information.
Cassegrain reflector is a combination of two coaxial reflectors used in Cassegrain telescopes and radio antennas.

First developed in 1672 by Laurent Cassegrain, this reflector is a combination of a primary concave mirror and a secondary convex mirror, both aligned
..... Click the link for more information.
In physics, wavelength is the distance between repeating units of a propagating wave of a given frequency. It is commonly designated by the Greek letter lambda (λ). Examples of wave-like phenonomena are light, water waves, and sound waves.
..... Click the link for more information.
Infrared (IR) radiation is electromagnetic radiation of a wavelength longer than that of visible light, but shorter than that of radio waves. The name means "below red" (from the Latin infra, "below"), red being the color of visible light with the longest wavelength.
..... Click the link for more information.
Area is a physical quantity expressing the size of a part of a surface. The term Surface area is the summation of the areas of the exposed sides of an object.

Units

Units for measuring surface area include:
square metre = SI derived unit

..... Click the link for more information.
F and focal length f of a positive (convex) lens, a negative (concave) lens, a concave mirror, and a convex mirror.]] The focal length of an optical system is a measure of how strongly it converges (focuses) or diverges (diffuses) light.
..... Click the link for more information.
European Space Agency (ESA), established in 1974, is an inter-governmental organisation dedicated to the exploration of space, currently with 17 member states. Its headquarters are in Paris.
..... Click the link for more information.
Ariane 5

Ariane 5 mock-up
Fact sheet
Function Heavy launch vehicle
Manufacturer EADS Astrium for
ESA and Arianespace
Country of origin Europe
Size
Height 59 m (193 ft)
Diameter 5.4 m (17.
..... Click the link for more information.
Please help [ improve this article] by expanding this section.
See talk page for details. Please remove this message once the section has been expanded. (tagged since April 2007)
The mission has a wide variety of scientific aims, including:[4]

..... Click the link for more information.
In orbital mechanics, a Lissajous orbit is a quasi-periodic orbital trajectory that an object can follow around a collinear libration point of a two-body system without requiring any propulsion.
..... Click the link for more information.
Lagrangian points (pronounced [ləˈgɹɒɲ.dʒi.ən] or [laˈgʀɑ̃.
..... Click the link for more information.
This is a list of known objects which have been, are or are planned to occupy any of the five Lagrangian points of two-body systems in space.

Sun-Earth Lagrangian points

L1

L1
..... Click the link for more information.
Frederick William Herschel, FRS KH (15 November 1738-25 August 1822) was a German-born British astronomer and composer who became famous for discovering Uranus. He also discovered infrared radiation and made many other discoveries in astronomy.
..... Click the link for more information.
Infrared (IR) radiation is electromagnetic radiation of a wavelength longer than that of visible light, but shorter than that of radio waves. The name means "below red" (from the Latin infra, "below"), red being the color of visible light with the longest wavelength.
..... Click the link for more information.
Infrared (IR) radiation is electromagnetic radiation of a wavelength longer than that of visible light, but shorter than that of radio waves. The name means "below red" (from the Latin infra, "below"), red being the color of visible light with the longest wavelength.
..... Click the link for more information.
Submillimetre astronomy or submillimeter astronomy (see spelling differences) is the branch of observational astronomy that is conducted at submillimetre wavelengths. It is often described as residing in the far-infrared or between the infrared and radio wavebands.
..... Click the link for more information.
spectrometer is an optical instrument used to measure properties of light over a specific portion of the electromagnetic spectrum, typically used in spectroscopic analysis to identify materials.
..... Click the link for more information.
For other uses, see Jansky (disambiguation).

The flux density or monochromatic flux, , of a source is the integral of the spectral radiance, , over the source solid angle:

In radio astronomy, the flux unit or jansky (symbol Jy
..... Click the link for more information.
Band may refer to a specific group:
  • Band (music), a company of musicians
  • Band (radio), a range of frequencies or wavelengths used in radio transmission
  • Band (algebra), an idempotent semigroup
  • Band society, a small group of humans in a simple form of society

..... Click the link for more information.
Solar System or solar system[a] consists of the Sun and the other celestial objects gravitationally bound to it: the eight planets, their 166 known moons,[1]
..... Click the link for more information.
Milky Way (a translation of the Latin Via Lactea, in turn derived from the Greek Γαλαξίας (Galaxias) sometimes referred to simply as "the Galaxy"), is a barred spiral galaxy that lies with the Local Group of galaxies
..... Click the link for more information.
Extragalactic astronomy is the branch of astronomy concerned with objects outside our own Milky Way Galaxy (the study of all astronomical objects which are not covered by galactic astronomy).

As instrumentation has improved, more distant objects can now be examined in detail.
..... Click the link for more information.
A galaxy (from the Greek root γαλαξίας, meaning "milky", a reference to our own Milky Way) is a massive, gravitationally bound system consisting of stars, an interstellar medium of gas and dust, and dark matter.
..... Click the link for more information.


This article is copied from an article on Wikipedia.org - the free encyclopedia created and edited by online user community. The text was not checked or edited by anyone on our staff. Although the vast majority of the wikipedia encyclopedia articles provide accurate and timely information please do not assume the accuracy of any particular article. This article is distributed under the terms of GNU Free Documentation License.
Herod_Archelaus


page counter