The 1/250/03 Reuters/Yahoo slop at right didn't compare it's cost to the cost of the average Mars mission.

SORCE Sent To Study The Sun
1/25/03

More Solar Chaos
11/3/03

Orbital Sciences Corporation's Lockheed L1011 releases a Pegasus
rocket, 1/25/03 off the coast of Cape Canaveral, Florida.
The rocket will deliver the SORCE satellite, Solar Radiation
and Climate Experiment, into low-Earth orbit.
The joint project, with Orbital, NASA and the University
of Colorado satellite, is sending up an atmospheric instrument
that will measure incoming radiant energy from the sun.
Scientists will use this to address long term atmospheric and climate changes.
Other uses will be for ozone research and ultraviolet radiation.
REUTERS/Eric Roback and Rob Rivers, NASA Langle
Research Center-Handout NO SALES Jan 26 12:32 AM ET