Space
Rockets Don't Go Up. They Go Sideways
Reaching space is the easy part; staying there takes enormous sideways speed. This Short explains why rockets pitch over soon after liftoff: almost all the energy of an orbit goes into moving horizontally, not climbing. Its takeaway is that orbit is about speed rather than height.
The numbers
- Space begins about 100 km up, roughly an hour's drive.
- Staying in orbit needs about 7.8 km/s of sideways speed.
- At that pace you'd cross from New York to Los Angeles in about 8 minutes.
- Nearly 90% of an orbit's energy comes from sideways speed.
Sources cited in the video: ESA · NASA · FAI · NASA Goddard Space Flight Center
