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The exploration of outer space - New Horizons passes Pluto
A tiny dot
When in 1930 the American astronomer Clyde Tombaugh spotted a tiny dot in his telescope he could hardly have imagined that in less than a century man would be able to take a close-up snapshot of this distant object. But on July 14, 2015 New Horizons, a probe launched by NASA in 2006 having traveled 5 billion km (3 billion mi) across space passed the tiny dot, taking fascinating shoots from Pluto and its moons in outer space.
Once believed to be about the size of the Earth and later reckoned to be much smaller, Pluto in the end turned out to be 2,370 km (1472 mi) across, about two-thirds the size of the Earth's moon. The visit of Pluto by New Horizons concludes the exploration of all planets of our solar system although, technically speaking, Pluto is no longer considered a planet.
The New Horizons probe
- about the size of a piano 478 kg (1,053 lb)
- 10,5 kg (23,2 lb)Plutonium as power source
- 14 km per second (31,000 mph)
- 700 million USD mission
- launched August 2006 from Cape Canaveral
Launched from Cape Canaveral in 2006 New Horizons traveled through space at the astonishing speed of 14 km per second (31,000 mph) for almost 10 years before reaching Pluto. Because of the extreme distance from earth very little was known of the dwarf planet before. Now preliminary images sent by New Horizons show a surface surprisingly unmarked by meteorite impacts with mountain ranges over 3 km high. Besides its cameras the probe is equipped with a series of sensors and lab instruments to provide maximum information possible, although full data transfer back to earth will take over a year.
Our solar system
Why was Pluto demoted?
In August 2006 the International Astronomical Union (IAU) kicked Pluto out of the club of planets. To be classified as planet an object in space must basically meet three criteria:
1. Has to be in orbit around a sun (which rules out the Earth's moon despite being bigger than Pluto)
2. Must have enough mass to have become spherical under force of its own gravity
3. Has to have cleared its orbit (either by absorbing or kicking out other objects)
Pluto, having other similarly sized bodies nearby, was reclassified because of point three. In fact Pluto is now considered to be the first major object from earth forming the so-called Kuiper-Belt, a group of hundreds if not thousands of bodies at the edge of our solar system.
In the meantime New Horizons, having power until 2025, is traveling on and continues to explore the Kuiper Belt. Once believed to be a disk of trillions of comet-sized icy bodies orbiting beyond Neptune at the outskirts of our solar system, it now looks more like hundreds or thousands of objects of much larger size similar to Pluto and its five moons. This somehow contrasts with the theory that the Kuiper Belt replenishes our solar system with comets. As comets loose mass over time when approaching the sun and the universe is supposed to be some 4,5 billion years old by most, albeit not all, scientists, their existence needs to be explained. Data supplied by New Horizons will undoubtedly help evaluate how far the Kuiper Belt fits this theory and thus shed some light on the theory of origins.
New Horizons: Passport to Pluto and Beyond
The future of space exploration
With New Horizons probe having reached the edge of our solar system and the famous Voyager probes launched in 1977 now in interstellar space the exploration of the outer solar system (Jupiter, Saturn, Uranus, Neptun) is coming almost to a halt (there remains the Juno mission expected to arrive at Jupiter in October 2016).
Although there is a renewed interest in space exploration by China, India and Japan their ambitions and focus is more on resuming maned spaceflight and do not go beyond Mars. A sign that outer planetary missions will not completely dry up is perhaps an agreement worth 50 million USD per year signed by NASA and the Department of Energy in 2013 to supply plutonium-238 - the indispensable power source for outer space probes.
Will mankind survive?
Some argue that planetary science is critical to the long-term survival of the human species. In light of the difficulties in even getting man to Mars and the huge distances involved in only getting to the edge of our own solar system one may doubt space exploration will provide a solution.
3000 years ago the psalmist David marveled about heaven: "The heavens declare the glory of God, and the sky above proclaims his handiwork. (Psalm 19:1). Whereas in the first part of this Psalm (v. 1-6) he speaks about nature and the general revelation of God, he then goes on (v. 7-14) to reflect on God's special revelation, his word, to mankind. The solution for the survival of the human species may be found here on earth rather than in outer space.