Date: Mon, 23 June 2008 13:07:00 (PDT)

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Subject: Spitzer Warm Mission Observing Proposals

Dear Colleagues,

NASA has authorized the Spitzer project to plan for approximately two
years of "warm" Spitzer observations after the cryogenic mission ends.
After cryogen depletion the observatory will continue operating
the 3.6 and 4.5 micron channels on the IRAC instrument with expected
sensitivity unchanged from performance in the cryogenic mission. The
longer wavelength IRAC channels (5.6 and 8.0 microns) and the MIPS
and IRS instruments will be unavailable.

In a two year "warm mission" we expect to execute ~13,000 hours of
science observations. Spitzer will operate with a substantially
reduced budget during the warm mission. To continue to produce first
class science with fewer resources to support the program, the warm
mission will focus on a new type of observing program, called
Exploration Science (ES), while continuing to support traditional GO
programs.

We plan to issue the Cycle-6 Call for Proposals on July 7, 2008.

Exploration Science General Observer Programs:

- minimum size of 500 hours

- 10,000 hours solicited for execution over two years

Regular General Observer Programs:

- maximum size of 500 hours

- 1,500 hours solicited for execution over one year

We anticipate a Cycle-7 Call for Proposals soliciting an additional
~1000-1500 hours of regular GO programs.

No Archival or Theoretical Research proposals are being solicited. It is
anticipated that archival research using the rich Spitzer archive will
be supported via other NASA programs. The SSC will advertise any such
programs as they become available. No joint observing programs with
other facilities are available in Cycle-6.

Key Dates
=========

Cycle-6 Call for Proposals  July 7, 2008

Exploration Science Proposals:

- Letters of Intent Due     September 2, 2008
- Proposals Due             October 10, 2008
- Proposals Selected        Early December 2008

Regular GO Proposals:

- Proposals Due             February 6, 2009
- Proposals Selected        May 2009

We continue to anticipate cryogen depletion in ~April 2009 with
Cycle-6 observations expected to begin in June 2009, after the
characterization period for the warm IRAC instrument and AOT.

Sincerely yours,

Lisa Storrie-Lombardi
Assistant Director for Community Affairs
Spitzer Science Center