The Space Infrared Telescope for Cosmology and Astrophysics (SPICA), was a proposed infrared space telescope, follow-on to the successful Akari space observatory. It was a collaboration between European and Japanese scientists, which was selected in May 2018 by the

European Space Agency , owners = , headquarters = Paris, Île-de-France, France , coordinates = , spaceport = Guiana Space Centre , seal = File:ESA emblem seal.png , seal_size = 130px , image = Views in the Main Control Room (1205 ...

(ESA) as a finalist for the next Medium class Mission 5 of the Cosmic Vision programme, to launch in 2032. At the time the other two finalists were THESEUS and EnVision, with the latter that was eventually selected for further development. SPICA would have improved on the spectral line sensitivity of previous missions, the Spitzer and Herschel space telescopes, between 30 and 230 µm by a factor of 50—100. A final decision was expected in 2021, but in October 2020, it was announced that SPICA was no longer being considered as a candidate for the M5 mission.

History

In Japan, SPICA was first proposed in 2007, initially called HII-L2 after the launch vehicle and orbit, as a large Strategic L-class mission,Cosmic Vision programme (M1 and M2), but an internal review at ESA at the end of 2009 suggested that the technology readiness for the mission was not adequate. In May 2018, it was selected as one of three finalists for the Cosmic Vision Medium Class Mission 5 (M5) for a proposed launch date of 2032. Within ESA, SPICA was part of the Medium Class-5 (M5) mission competition, with a cost cap of 550M Euros. It stopped being a candidate for M5 in October 2020 due to financial constraints.

Overview

The concept was a collaboration between the

(ESA) and the

Japan Aerospace Exploration Agency The is the Japanese national air and space agency. Through the merger of three previously independent organizations, JAXA was formed on 1 October 2003. JAXA is responsible for research, technology development and launch of satellites into orb ...

(JAXA). If funded, the telescope would have been launched on JAXA's H3 launch vehicle. The

Ritchey–Chrétien telescope A Ritchey–Chrétien telescope (RCT or simply RC) is a specialized variant of the Cassegrain telescope that has a hyperbolic primary mirror and a hyperbolic secondary mirror designed to eliminate off-axis optical errors (coma). The RCT has a wi ...

's 2.5-metre mirror (similar in size to the mirror of the

Herschel Space Observatory The Herschel Space Observatory was a space observatory built and operated by the European Space Agency (ESA). It was active from 2009 to 2013, and was the largest infrared telescope ever launched until the launch of the James Webb Space Telesc ...

) would have been made of silicon carbide, possibly by ESA given their experience with the Herschel telescope. The main mission of the spacecraft would have been the study of

star A star is an astronomical object comprising a luminous spheroid of plasma (physics), plasma held together by its gravity. The List of nearest stars and brown dwarfs, nearest star to Earth is the Sun. Many other stars are visible to the naked ...

and

planetary formation The nebular hypothesis is the most widely accepted model in the field of cosmogony to explain the formation and evolution of the Solar System (as well as other planetary systems). It suggests the Solar System is formed from gas and dust orbiting t ...

. It would have been able to detect stellar nurseries in

galaxies A galaxy is a system of stars, stellar remnants, interstellar gas, dust, dark matter, bound together by gravity. The word is derived from the Greek ' (), literally 'milky', a reference to the Milky Way galaxy that contains the Solar System. ...

, protoplanetary discs around young stars, and exoplanets, helped by its own coronograph for the latter two types of objects.

Description

The observatory would have featured a far-infrared spectrometer and was proposed to be deployed in a

halo orbit A halo orbit is a periodic, three-dimensional orbit near one of the L1, L2 or L3 Lagrange points in the three-body problem of orbital mechanics. Although a Lagrange point is just a point in empty space, its peculiar characteristic is that it ca ...

around the

L2 point In celestial mechanics, the Lagrange points (; also Lagrangian points or libration points) are points of equilibrium for small-mass objects under the influence of two massive orbiting bodies. Mathematically, this involves the solution of th ...

. The design featured V-groove radiators and mechanical

cryocooler A refrigerator designed to reach cryogenic temperatures (below ) is often called a cryocooler. The term is most often used for smaller systems, typically table-top size, with input powers less than about 20 kW. Some can have input powers as lo ...

s rather than liquid helium to cool the mirror to below

History

Overview

Description

Objectives

Discovery science

See also

References

External links