The Obama administration on Wednesday will unveil its much-delayed
general plans for its rocket design, called the Space Launch System,
which will cost about $35 billion, according to senior administration
sources and information obtained by The Associated Press. It will carry
astronauts in a capsule on top and start test launching in six years.
The size, shape and heavier reliance on
liquid fuel as opposed to solid rocket boosters is much closer to Apollo
than the recently retired space shuttles, which were winged, reusable
ships that sat on top of a giant liquid fuel tank, with twin solid
rocket boosters providing most of the power. It's also a shift in
emphasis from the moon-based, solid-rocket-oriented plans proposed by
the George W. Bush administration.
"It's back to the future with a reliable liquid technology," said Stanford University professor Scott Hubbard, a former NASA senior manager who was on the board that investigated the 2003 space shuttle Columbia accident.
NASA figures it will be building and
launching about one rocket a year for about 15 years or more in the
2020s and 2030s, according to senior administration officials who spoke
on the condition of anonymity because the announcement was not yet
made.
The idea is to launch its first unmanned
test flight in 2017 with the first crew flying in 2021 and astronauts
heading to a nearby asteroid in 2025, the officials said. From there,
NASA hopes to send the rocket and astronauts to Mars -- at first just to
circle, but then later landing on the Red Planet -- in the 2030s.
At first the rockets will be able to carry
into space 77 tons to 110 tons of payload, which would include the
six-person Orion Multi-Purpose Crew Vehicle capsule and more. Eventually
it will be able to carry 143 tons into space, maybe even 165 tons, the
officials said. By comparison, the long-dormant Saturn V booster that
sent men to the moon was able to lift 130 tons.
The plans dwarf the rumbling lift-off power
of the space shuttle, which could haul just 27 tons. The biggest current
unmanned rocket can carry about 25 tons.
The size of the plans elicited an amazed
"good grief" from Hubbard, who said it would limit how often they could
be built or launched. Unlike the reusable shuttle, these rockets are
mostly one-and-done, with new ones built for every launch.
Some of the design elements, the deadline and the requirement for such a rocket were dictated by Congress.
While the recently retired space shuttle's
main engines were fueled by liquid hydrogen and liquid oxygen, it was
primarily powered into orbit by solid rockets. Solid rocket boosters
were designed to be cheaper, but a booster flaw caused the fatal space shuttle Challenger accident in 1986. The biggest drawback was that solid rockets can't be stopped once they are lit; liquid ones can.
The new plan is to use a giant rocket
powered by liquid hydrogen and liquid oxygen. Apollo, Gemini and Mercury
flew into space on liquid rockets, and liquids fuel most of the world's
unmanned commercial rockets. Russia's Soyuz rocket is liquid fueled
too.
During its initial test flights the rocket
will use five solid rocket boosters designed for the shuttle strapped on
its outside and will have shuttle main engines powering it on the
inside. But soon after that the solid rocket boosters will be replaced
with new boosters that should have new technology and may be either
liquid or solid, the officials said
NASA figures it will spend about $3 billion a
year on the plan, officials said. The key financial part of this
arrangement is that NASA hopes to save money by turning over the
launching of astronauts to the International Space Station,
which orbits the Earth, to private companies and just rent spaces for
astronauts like a giant taxi service. NASA would then spend the money on
leaving Earth's orbit and the Earth-moon system.
Hubbard worries that NASA has a history of
spending way more than initially proposed -- the space shuttle cost
about twice what it was supposed to -- and this new rocket system will
drain money from other NASA missions.
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