Space travel has become much safer as scientists have overcome potential problems, but itâs still dangerous. Itâs also very expensive. In order for a space shuttle to break free of Earthâs gravity, it has to travel at a speed of 15, 000 miles per hour. Space shuttles need 1.9 million liters of fuel just to launch into space. Thatâs enough fuel to fill up 42, 000 cars! Combine the high speed, heat and fuel needed for launching and youâve got a very potentially dangerous situation.
Re-entering the atmosphere is dangerous too. When a space craft re-enters the atmosphere, it is moving very fast. As it moves through the air, friction causes it to heat up to a temperature of 2, 691 degrees. The first spacecrafts were destroyed during re-entry. Todayâs space shuttles have special ceramic tiles that help absorb some of the heat, keeping the astronauts safe during re-entry.
- One space shuttle launch costs 0 million.
- The German V2 was the first rocket to reach space in 1942.
- In 1947, fruit flies were launched into space. Scientists wanted to see how they reacted to space travel. Later, in 1949, Albert II, a Rhesus monkey went to space. In 1957, the Russian space dog, Laika, orbited the Earth. Scientists wanted to make sure space travel was safe for humans. Sending animals first gave them valuable information about how bodies react to being in space.
- Russian astronaut, Yuri Gagarin, was the first human in space. He orbited the Earth in 1961.
- In 1963, the first woman, Valentina Tereshkova, entered space.
- On July 20, 1969, Neil Armstrong and Buzz Aldrin became the first men to walk on the moon and return home safely â a journey of 250, 000 miles.
- In 1970, Apollo 13 was headed to the moon when an explosion on board caused serious problems. The astronauts fixed the problems with materials they had on hand and returned home safely.
- US astronauts returned to the moon three more times in 1971.
- 1981 marked the first space shuttle that could be used again. Six shuttles have been built since then.
- In 1986, Space Shuttle Challenger exploded shortly after launch, killing all seven astronauts onboard, including school teacher, Christa McAuliffe.
- Since 2000, permanent crews have been living and working in space at the International Space Station.
- In 2001, the first private citizen, millionaire Dennis Tito, toured space. He paid $20 million to spend a week in space.