The Universe in the Infrared What is the Spitzer Space Telescope, and how does it work? Funded by NASA’s Spitzer Science Center Images courtesy NASA/JPL

The Universe in the Infrared

What is the Spitzer Space Telescope, and how does it work?

Funded by NASA’s Spitzer Science Center

Images courtesy NASA/JPL - Caltech

Pilachowski / August 2005


Slide 2

Outline

NASA’s Great ObservatoriesIntroducing SpitzerSpitzer’s LaunchOrbitNaming SpitzerThe TelescopeInstrumentsFuture IR Telescopes



Slide 3

NASA’s Great Observatories

Spitzer is the final spacecraft in NASA's Great Observatories program

HST 1990

Compton GRO 1991

Chandra 1999



Slide 4

Introducing Spitzer

The Spitzer Space Telescope is a cryogenically cooled, infrared observatory in space.

Spitzer can study objects ranging from our Solar System to the distant reaches of the Universe.



Slide 5

Launch

• Launched from KSC on25 August 2003

• Lifetime:2.5 years (minimum); 5+ years (goal)



Slide 6

Heliocentric Orbit

• Most space telescopes orbit the Earth

• Spitzer orbits the Sun - trailing the Earth as it moves around the Sun

• Spitzer is receding from Earth at 9.3 million miles (15 million kilometers) per year

• Spitzer now trails the Earth in its orbit by about 20 million miles (~ 32 million kilometers)

• By 2008, Spitzer will be about 56 million miles or 90 million kilometers away



Slide 7

Named for Lyman Spitzer

Lyman Spitzer was the driving force behind HST

Founded the study of the interstellar medium

Studied interstellar dust and star formation



Slide 8

Introducing the Telescope

http://ssc.spitzer.caltech.edu/



Slide 9

Spitzer Specs

Mirror:85 cm (33.5”) diameterlightweight beryllium f/12 curvature

Weight: Telescope: 851.5 kgHe cryogen: 50.4 kgN propellent: 15.6 kg




Slide 10

Keeping Spitzer Cold

• Telescope operates at 5.5 K

• Why? - Spitzer is itself a black body radiator, and must be colder than the astronomical sources it detects

• How?– Heliocentric orbit– Solar shield/solar cells– Outer shell insulates

and cools the telescope




Slide 11

Keeping Spitzer’s Instruments Even Colder

A tank of liquid helium is used to keep Spitzer’s instruments and detectors at 1.5 K



Slide 12

Spitzer’s Instruments

• IRAC – InfraRed Array Camera– images at 3.6, 4.5, 5.8, and 8 m

• IRS – InfraRed Spectrograph– mid-IR spectroscopy

• MIPS – Multiband Imaging Photometer for Spitzer– images at 24, 70, and 160 m

IRS

MIPS IRAC




Slide 13

InfraRed Array Camera (IRAC)

• Built at the Smithsonian Astrophysical Observatory

• Simultaneous images in four IR passbands



Slide 14

InfraRed Spectrometer

• Built at Cornell University• Spectroscopy in the mid-IR



Slide 15

Multiband Imaging Photometer for Spitzer (MIPS)

• Three detector arrays– 128x128 pixel Si:As for 24 mm– 32x32 pixel Ge:Ga for 70 mm– 2x20 pixel Ge:Ga for 160 mm

Built at the University of Arizona



Slide 16

Spitzer Focal Plane

Spitzer instruments are arranged in fixed locations on the Spitzer focal planeThe telescope is rotated to move a particular science target to the right position for the instrument to be usedOther instruments record data for “serendipitous” fields



Slide 17

Spitzer Operations

www.spitzer.caltech.edu/about/now.shtml

What Is Spitzer Doing Now?

http://www.spitzer.caltech.edu/about/now.shtml

http://www.spitzer.caltech.edu/about/now.shtml




Slide 18

Future Infrared Satellites

2007: Herschel Space Observatory - a European Space Agency infrared-submillimeter mission planned for 2007 to study galaxy formation, interstellar matter, star formation and the atmospheres of comets and planets.

2007: Planck Surveyor - European Space Agency far infrared-submillimeter mission planned for 2007 to study Cosmic Background Radiation.

2010: The James Webb Space Telescope, planned for launch in about 2011, is a visible/infrared space mission to study the early universe and the formation of galaxies, stars and planets.

Documents

The Universe in the Infrared What is the Spitzer Space Telescope, and how does it work? Funded by NASA’s Spitzer Science Center Images courtesy NASA/JPL