SPICA telescope
Encyclopedia
The Space Infra-Red Telescope for Cosmology and Astrophysics telescope (SPICA), initially called HII/L2 after the launch vehicle and orbit, is a proposed infrared
space telescope, successor of the successful AKARI
spacecraft
.
(JAXA), and the telescope will be launched on an H-IIA
rocket. The Ritchey-Chrétien telescope
's 3.5-metre mirror (similar size to that of the Herschel Space Observatory
) is to be made of silicon carbide
, possibly by the European Space Agency
(ESA) given their experience with Herschel. Currently planned to be launched in 2017, the spacecraft's main mission will be the study of star
and planetary formation. It will be able to detect stellar nurseries in galaxies
, protoplanetary discs around young star
s, and exoplanets, helped by its own coronograph for the latter two types of objects.
, allowing the mirror to be cooled to (versus the or so of a mirror cooled only by radiation like Herschel's) which provides substantially greater sensitivity in the 10–100 μm
infrared band (IR band); the telescope is intended to observe in longer wavelength infrared than the James Webb Space Telescope
.
, it is expected to be launched in 2018.
Infrared
Infrared light is electromagnetic radiation with a wavelength longer than that of visible light, measured from the nominal edge of visible red light at 0.74 micrometres , and extending conventionally to 300 µm...
space telescope, successor of the successful AKARI
Akari
Akari is a Japanese surname and given name and term meaning "light" or "glimmer". It is also associated with:* AKARI, in astronomy, is an infrared astronomy satellite developed by JAXA, in cooperation with institutes of Europe and Korea...
spacecraft
Spacecraft
A spacecraft or spaceship is a craft or machine designed for spaceflight. Spacecraft are used for a variety of purposes, including communications, earth observation, meteorology, navigation, planetary exploration and transportation of humans and cargo....
.
Background
The project is led by the Japan Aerospace Exploration AgencyJapan Aerospace Exploration Agency
The , or JAXA, is Japan's national aerospace agency. Through the merger of three previously independent organizations, JAXA was formed on October 1, 2003, as an Independent Administrative Institution administered by the Ministry of Education, Culture, Sports, Science and Technology and the...
(JAXA), and the telescope will be launched on an H-IIA
H-IIA
H-IIA is an active expendable launch system operated by Mitsubishi Heavy Industries for the Japan Aerospace Exploration Agency . The liquid-fueled H-IIA rockets have been used to launch satellites into geostationary orbit, to launch a lunar orbiting spacecraft, and to launch an interplanetary...
rocket. The Ritchey-Chrétien telescope
Ritchey-Chrétien telescope
A Ritchey–Chrétien telescope is a specialized Cassegrain telescope designed to eliminate coma, thus providing a large field of view compared to a more conventional configuration. An RCT has a hyperbolic primary and a hyperbolic secondary mirror. It was invented in the early 1910s by American...
's 3.5-metre mirror (similar size to that of the Herschel Space Observatory
Herschel Space Observatory
The Herschel Space Observatory is a European Space Agency space observatory sensitive to the far infrared and submillimetre wavebands. It is the largest space telescope ever launched, carrying a single mirror of in diameter....
) is to be made of silicon carbide
Silicon carbide
Silicon carbide , also known as carborundum, is a compound of silicon and carbon with chemical formula SiC. It occurs in nature as the extremely rare mineral moissanite. Silicon carbide powder has been mass-produced since 1893 for use as an abrasive...
, possibly by the European Space Agency
European Space Agency
The European Space Agency , established in 1975, is an intergovernmental organisation dedicated to the exploration of space, currently with 18 member states...
(ESA) given their experience with Herschel. Currently planned to be launched in 2017, the spacecraft's main mission will be the study of star
Star formation
Star formation is the process by which dense parts of molecular clouds collapse into a ball of plasma to form a star. As a branch of astronomy star formation includes the study of the interstellar medium and giant molecular clouds as precursors to the star formation process and the study of young...
and planetary formation. It will be able to detect stellar nurseries in galaxies
Galaxy
A galaxy is a massive, gravitationally bound system that consists of stars and stellar remnants, an interstellar medium of gas and dust, and an important but poorly understood component tentatively dubbed dark matter. The word galaxy is derived from the Greek galaxias , literally "milky", a...
, protoplanetary discs around young star
Star
A star is a massive, luminous sphere of plasma held together by gravity. At the end of its lifetime, a star can also contain a proportion of degenerate matter. The nearest star to Earth is the Sun, which is the source of most of the energy on Earth...
s, and exoplanets, helped by its own coronograph for the latter two types of objects.
Project plan
It is intended to use a halo orbit around the L2 point; it is intended to use mechanical cryocoolers rather than liquid heliumLiquid helium
Helium exists in liquid form only at extremely low temperatures. The boiling point and critical point depend on the isotope of the helium; see the table below for values. The density of liquid helium-4 at its boiling point and 1 atmosphere is approximately 0.125 g/mL Helium-4 was first liquefied...
, allowing the mirror to be cooled to (versus the or so of a mirror cooled only by radiation like Herschel's) which provides substantially greater sensitivity in the 10–100 μm
Micrometre
A micrometer , is by definition 1×10-6 of a meter .In plain English, it means one-millionth of a meter . Its unit symbol in the International System of Units is μm...
infrared band (IR band); the telescope is intended to observe in longer wavelength infrared than the James Webb Space Telescope
James Webb Space Telescope
The James Webb Space Telescope , previously known as Next Generation Space Telescope , is a planned next-generation space telescope, optimized for observations in the infrared. The main technical features are a large and very cold 6.5 meter diameter mirror, an observing position far from Earth,...
.
Intended focal-plane instrumentation
- SAFARI: 30–200 μm imaging spectrometerImaging spectrometerAn imaging spectrometer is an instrument used in hyperspectral imaging and imaging spectroscopy to acquire a spectrally-resolved image of an object or scene, often referred to as a datacube due to the three-dimensional representation of the data. Namely, two axes of the image corresponds to...
(to be provided by ESA) - CoronaCoronaA corona is a type of plasma "atmosphere" of the Sun or other celestial body, extending millions of kilometers into space, most easily seen during a total solar eclipse, but also observable in a coronagraph...
graphic instrument for detecting Jupiter-scale exoplanets, working in the 5–20 μm range, also usable as an unobstructed imager. - High-resolution spectrographSpectrographA spectrograph is an instrument that separates an incoming wave into a frequency spectrum. There are several kinds of machines referred to as spectrographs, depending on the precise nature of the waves...
for 4–40 μm - Low-resolution spectrograph for 10–100 μm
Timeline
The mission has been planned for many years; the launch date as of 2005 was "early 2010s", though as of 2009 a great deal of hardware has been designed but very little built, the SPICA website indicates that in summer 2009 the mission is still at the conference stage, and the 2009 paper says 'within ten years'.. An internal review at ESA at the end of 2009 suggested that the technology readiness for the mission was not adequate, it is expected to be launched in 2018.
External links
- Official site - JAXA