Skip to main content

Extending Science NASA's Space Science Mission Extensions and the Senior Review Process (2016) / Chapter Skim
Currently Skimming:

4 The Balance of New Missions Versus Extended Missions
Pages 48-52

The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.


From page 48...
... is currently operating approximately 60 science missions, of which approximately three-fourths are in their extended mission phase and one-fourth in their prime phase. This complementary arrangement has proved effective in enabling all four mission divisions to achieve scientific goals that could not have been reached with either primary or extended missions alone.
Read the entire page →
From page 49...
... The committee is unaware of any published evaluation of what constitutes the "proper" balance between new and extended phase missions, other than the 2005 National Research Council report Extending the Effective Lifetimes of Earth Observing Research Missions (NRC, 2005)
Read the entire page →
From page 50...
... The Heliophysics System Observatory, which relies upon multiple observations at multiple locations, would simply collapse. The results for the Planetary Sciences Division are similar: canceling all operating extended phase missions -- Curiosity, Opportunity, Lunar Reconnaissance Orbiter, Mars Reconnaissance Orbiter, MAVEN, Cassini, and even New Horizons, which will finish its prime phase soon -- would result in approximately one new Discovery mission every 2-plus years, or one new flagship class mission every decade (see Table 4.1)
Read the entire page →
From page 51...
... Finding: NASA's extended science missions constitute approximately three-fourths of the missions in flight, but cost a relatively small percentage of the overall SMD budget, on average 12 percent over the last 5 years. Finding: Eliminating all of the extended missions would • Increase the funds available for new development only by approximately 25 percent; • Make it difficult or impossible to achieve many objectives of decadal survey science; and • Adversely and significantly impact SMD's overall science return.
Read the entire page →
From page 52...
... 52 EXTENDING SCIENCE -- NASA'S SPACE SCIENCE MISSION EXTENSIONS AND THE SENIOR REVIEW PROCESS FIGURE 4.2  The Mars Reconnaissance Orbiter not only performs extended mission science at Mars but also serves as a relay spacecraft for the Opportunity and Curiosity rover missions. Ending operating Mars orbiters would eliminate vital infrastructure supporting other missions in both prime and extended phase.
Read the entire page →

Key Terms

  • extended phase
  • science missions
  • science division
  • current balance
  • extended science

  • science mission
  • space science
  • phase missions
  • class mission
  • prime phase

  • reconnaissance orbiter
  • flagship class
  • extended mission
  • extended phases
  • mission extensions

  • operating missions
  • nasa missions
  • planetary science
  • discovery mission
  • earth science

  • launch costs
  • mars reconnaissance
  • decadal surveys
  • division canceled
  • including launch

  • approximate buying
  • buying power
  • operating extended
  • current extended
  • divisions spends


    • This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
    More information on Chapter Skim is available.