ThIs [BBC](https://www.bbc.com/news/science-environment-57797297) article states that the passengers experienced weightlessness for 5 minutes – how is this possible? Is it at the descent? They are much too close to the earth to not experience a lack of gravity.
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Weightlessness ≠ lack of gravity
Weightlessness is when you and your ship and all the air in your ship are experiencing the same forces, be they gravity or air resistance. In your frame of reference, the ship is moving with you.
The ISS and the Unity both experience the same gravitational forces and have the same weightlessness inside them. The ISS is moving faster, so it can sustain weightlessness for years, but that’s the only difference. The Earth’s gravity extends a long way, that’s what’s keeping the Moon in orbit after all.
Here’s a funny fact: gravity doesn’t make you feel heavy. Gravity is- sort of- not the reason you have ‘weight’ that you feel.
The ground is. Well, sort of.
Gravity pulls you down, and with nothing in your way you keep falling. When you’re falling, you feel no weight. Gravity pulls, and you fall, and everything is balanced out. But when you’re on the ground, the ground is in the way! It’s pushing back, preventing you from falling further. And it’s the pull of gravity plus the push of the ground that is ‘weight’ that you feel. If nothing is pushing you up, like the ground does, you feel weightless.
Astronauts in the ISS are in orbit. That means that they are still falling towards the earth, but they’re moving so fast sideways that they ‘miss’ it. They’re falling forever, because gravity is still pulling very hard on the station but the path they’re taking doesn’t let them hit the earth.
Branson and his space plane flew up just beyond the line that some people use to define ‘the edge of space’. The space plane flew up really really hard, then stopped accelerating and coasted to a maximum height of a little more than 50 miles or 80km. After it reached it’s maximum height, it fell back down. And between when they turned the engines off and when they started to slow down again, they were in freefall- no weight.
Sadly Branson’s space plane isn’t powerful enough to fly sideways fast enough to reach orbit. That takes a LOT of energy. It’s really cool, but not very big.
Basically they experienced the same kind of weightlessness as those who go training in the NASA ‘vomit comet’ – accelerate upward, and as the craft reaches a peak, and is somewhere between climb and descent, they float around.
Branson just went higher and faster
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