Michael Laine, the CEO of LiftPort, a commercial advocate of space
elevators, says he plans to have a usable elevator anchored in the
Pacific Ocean near the equator by April 12, 2018. LiftPort's outer
space precursor hit a 1,000-foot benchmark in September 2005, but
it clearly has a long climb ahead. Laine also believes his company
can bring payload costs down to $400 a pound, a huge reduction from
the many thousands of dollars per pound it currently costs to get
people and satellites into geosynchronous orbit via rockets.
HEY, HOT STUFF
Step aside, solids, liquids, and gases. Plasma has arrived, and
former astronaut
Franklin Chang Diaz, who has been to space seven
times on conventional chemical rockets, wants to travel with
plasma. "If you heat a gas enough, the atoms break apart, and you
get plasma. It's a fourth state of matter that's really, really
hot. Plasma is everywhere in space," he says. "It's what our stars
and sun are, really."
The hotter the exhaust, the zippier the rockets. Right now, rocket
exhaust is in the thousands of degrees. "That's a pretty cold
fuel," says Chang Diaz. "Plasma exhaust will be millions of degrees
hot."
He's talking about fueling an ionically souped-up engine that can
shift gears through space and get humans to Mars in three or four
months instead of the minimum 10 months projected for chemical
rockets. Better travel speed could greatly reduce the wearying
weeks of boredom, the bone weakening of weightlessness, and the
dangerous levels of exposure to solar radiation that space
travelers face on long trips.
The plasma rocket is too hot (by just a few million degrees) to
launch from Earth. One idea is to assemble it in space, like the
ISS. Current plans to heat the plasma are for the power source to
be electrical - possibly converting solar energy for close to Earth
and using nuclear reactors for deep space.