It could land anywhere from New York, Madrid and Beijing and as far south as southern Chile and Wellington, New Zealand.
In 1986, Nelson, a sitting lawmaker, was a crew member on the Space Shuttle Columbia during a six-day mission in space.
The four astronauts on Crew-1 are NASA astronauts Victor Glover, Michael Hopkins, Shannon Walker and JAXA astronaut Soichi Noguchi.
It is expected to remain in low orbit at between 400 and 450 kilometres above Earth for a lifespan of around 15 years.
When completed by late 2022, Tianhe is expected to weigh about 66 tons, a fraction the size of the International Space Station.
The current population includes six Americans, two Russians, two Japanese and one French.
With a data relay satellite, other satellites can pass their information to the ground stations even if it's out of range.
"The first core module of the new Russian orbital station is in the works," Rogozin said in a statement.
This was the second missions for Kate Rubins, and Sergei Ryzhikov Ryzhikov but first mission for Sergei Kud-Sverchkov.
He was added to the next Soyuz crew, in order to keep a constant US presence on the ISS, as operations would be hampered if no Americans were on board.
More than 3,000 experiments have been carried out in this microgravity laboratory, which flies at an average of 400 kilometres above Earth, at 28,000 km/h.
On the seven-hour spacewalk, astronauts had already spent enough time in sunlight to bake off the ammonia on their suits, Mission Control said.
China is also at work on reusable spacecrafts, a crewed moon mission and a possible permanent research base on the moon, though no dates have been proposed.
he Starliner's first crewed flight is currently scheduled for September.
The eight existing solar panels on the ISS are 12 to 20 years old which is past their design lifetime and deteriorating.
A key experiment shipped in the Cygnus cargo ship uses a light-activated protein to replace the function of damaged cells in the eye.
The spacecraft is carrying 1,400 kg of research and crew supplies, freshwater, nitrogen gas and propellant for ISS' Zvezda service module propulsion system.
The deal has set NASA back by thrice the cost of the 2022 Falcon Heavy launch of a probe to study the asteroid Psyche.
The Dragon capsule had become the first spacecraft to be certified by NASA since the Space Shuttle nearly 40 years ago.
An observatory on the space station captured a single blue jet and four ‘elves’ – UV emissions from the bottom of the ionosphere – during a thunderstorm.