I Have Been Following Orion Space Launch And Reentry

[Kim Jong-Un's Pajama Pants]

• Tweet

It went like clock work.  It looks like humans will soon be heading back into deep space.  Last time this happened was 1972.  NASA is talking really deep space.  Past the moon to an asteroid. 

The capsule on a Delta IV Heavy rocket flew 3,600 miles out and fell back to earth with speeds of upto 32,000 kmh(85% of the kinds of speeds you expect falling in from the moon).

[veritas]

I want to build a spaceship oneday.

[RV Pundit]

That is amazing

[Kim Jong-Un's Pajama Pants]

These kind of tests wouldn't be necessary if fuel is not an issue. 

Escaping the moon's gravitation takes lots of fuel.  They compensate by relying on earth's gravitation once they exit the moon's Hill sphere.  A mere 60,000 km from the moon.

That means the poor capsule is falling to earth all the way from 320,000 km.  It costs yet more fuel to overcome the kinetic energy gained, slowing it down to those still ridiculous reentry speeds. 

The goal is to slow it down to a point where the heat shield can handle reentry. 

[veritas]

Fascinating. Thanks.

You'd think they'd have invented sustainable fuel by now.