[Revising...]

Improvement in the utility per kg for systems on robotic spacecraft make them increasingly attractive to space agencies for increasing numbers and types of missions.

Even as NASA concentrates its resources on manned lunar and Martian expeditions, unmanned space exploration may find new prominence and greater funding in an effort to replace more costly, less productive science performed on manned missions.

Though ESA's budget ($3.8 billion for FY2005) is roughly a quarter of NASA's ($16 billion for FY2006), ESA's agility and relative lack of legacy programs will help it to achieve more with less funding. Over the coming decade, ESA has concrete plans for unmanned missions to Venus, Mars, Mercury, and in conjunction with the Indian space agency, the moon. ESA will probably use knowledge developed in these programmes, and especially research on new propulsion technologies, to launch even more probes in the years up to 2020 and beyond. Unified platforms and systems of systems will reduce overall costs. Initial probe development promises to beget less expensive probes in the future.

Building upon programmes planned for the 2010 to 2020 timeframe, scientists hope to be able to construct 3D maps of the galaxy, gain a better understanding of the origins of the universe, and search for Earth-like planets. Microsatellites, launched for less than $10 million apiece (for example, Canada's MOST space telescope), will probably play an important role in these discoveries by allowing astronomers more time for otherwise low-priority experiments. Upon its launch around 2011, NASA's James Webb Space Telescope will study the origins of the universe using infrared sensors, if its progress is not hampered by further budget cuts and downsizing.

This will be enabled by:

Expense and inefficiency of scientific experimentation on manned missions

Early indicators include:

Construction by ESA of its Venus Express, using the same platform as the successful Mars Express
Testing of an ion propulsion system by ESA's SMART-1 probe
Wavering by NASA on rehabilitating the Hubble Space Telescope and its lack of planning for a direct replacement
Cutting from NASA's 2006 budget of its Jupiter Icy Moons Orbiter (JIMO), long planned as a testbed for advanced probe technology

What to watch:

An increasing number of scientific papers cite the Hubble Space Telescope rather than the International Space Station.
US cuts funding for deep-space exploration, unmanned programs, and 'blue sky' projects.

Better knowledge of our solar system and those yet unexplored
Potential for discovery of extraterrestrial life
Better understanding of the moments following the Big Bang
Better understanding of the composition and history of Mars, Mercury, and Venus