７０ Space Travel【Space Travel】Dialogue with the Universe

７０　Space Travel【Space Travel】Dialogue with the Universe

７０－１　The Wall of Time
At a rate of traditional space ship it takes
・5 months to Mars. [1]（It takes 2.6 years to round trip due to the revolution of the Earth and Mars.）
・20 to 30 years to out of Solar System
・30,000 years to go to our nearest neighbouring star, Alpha Centauri (distance: four light years). [1]

⇒Human colonization of other planets will be achieved by intelligent machines consisting of mechanical and electronic components.- Stephen William Hawking

⇒If humans are required, it will be reproduced from the DNA information. [2]

※Maximum speed of the vehicle, which was invented by human is 111km / s in the Apollo 10. [3]

７０－２　A New System：Laser-Powered Engine
：Propulsion of spacecraft is obtained by irradiation of the laser to the sail. (Use of Solar wind is also possible)
：The system can propel spacecraft to 30% of lightspeed. [1]
：This could get a 100 kilogram robotic craft to Mars in three days.( A craft occupied by humans would take slightly longer -- but at a month.) [1]

○Tasks：
・Energy source
・It is necessary to install the base on the planet orbit.
・There is a need also to set up a base on the arrival point for deceleration.

※Lightspeed＝300,000km / s

○Development status of laser propulsion system
1973－1975　Mariner 10(USA) which flew by the planets Mercury and Venus demonstrated the use of solar pressure as a method ofattitude control in order to conserve attitude-control propellant. [4] [5]
2010　Japan Aerospace Exploration Agency (JAXA) launched the world's first interplanetary solar sail spacecraft"IKAROS" (Interplanetary Kite-craft Accelerated by Radiation Of the Sun) to Venus. [4]
2015　Light Sail-A (The Planetary Society) was successfully tested to deploy a solar sail.

７０－３　Antimatter Spaceship [6]
・Causing the "annihilation" of positrons and electrons to get the driving force of the spacecraft.
・Expected to be 40% of the speed of light.
・10 years to go to our nearest neighbouring star, Alpha Centauri (distance: four light years).

○Problems
・To save antimatter is not possible with current technology (1g antimatter is the same destructive power as an atomic bomb).
・The anti-hydrogen required for the journey towards the nearest star is about 17g, but the cost of making the antimatter 1g is about 1,000 billion＄.

７０－４　Planet Type Spacecraft
○For long-term space travel of humans, we must have Planet type spacecrafts.
※ Planet type spacecraft;PTS：Which is a Spacecraft Modified a Planet for ultra-long-term space travel.

【References】
1. Nasa's laser-powered engine could get us to Mars in 72 hours
http://www.wired.co.uk/news/archive/2016-02/22/laser-propulsion-system-mars-in-3-days
2. Ｎｏ．３８ Brain
3. Un kickstarter per sviluppare il motore ad antimateria(ITALIA)
http://www.wired.it/scienza/spazio/2016/03/03/kickstarter-per-sviluppare-motore-ad-antimateria/
4. Wikipedia：Solar sails (also called light sails or photon sails)
https://en.wikipedia.org/wiki/Solar_sail
5. Mariner 10
http://solarviews.com/eng/marin10.htm
6. New and Improved Antimatter Spaceship for Mars Missions
http://www.nasa.gov/centers/goddard/news/topstory/2006/antimatter_spaceship.html