tware to detect this wobble, and applying the “wobble-means-planet” theory, researchers have claimed to have found some 573 extrasolar planets (as of 9 August 2011—Ed.), including the first claimed three-planet solar system (around Upsilon Andromedae, about 44 light years from Earth).17
None of the claimed extrasolar planets fulfil any of the conditions needed to support life, so the search continues for Earth-sized planets (the optimum size for life as we know it). An Earth-sized planet would have about 1/300th of the gravitational pull of Jupiter (at the same distance), as Jupiter is 318 times the mass of Earth, and so any wobble an Earth-sized planet might cause would be too small to be detected with current equipment. Further research is proceeding.
If any extrasolar planets capable of supporting life were to be found, several major problems would inhibit any rocks from carrying such life to Earth. These are:
1. The need to achieve escape velocity
For a rock (or spacecraft) to break free from the pull of gravity of its mother planet, it must achieve a speed called the escape velocity. For Earth this is 11.18 km per second, or 40,248 kph (25,009 mph). For Mars it is 5.02 km per second, or 18,072 kph (11,229 mph). As volcanoes do not eject materials at these speeds, scientists postulate that rocks are blasted from planets and into space through giant asteroid collisions.
2. The tyranny of distance
The nearest star to Earth is Alpha Centauri. It is 4.37 light years away, which means that light—travelling at 300,000 km (186,000 miles) per second—takes 4.37 years to reach us, 40 million million km away. If an Earth-sized planet (the optimum size) were orbiting Alpha Centauri and a rock were blasted from it at the speed of Earth’s escape velocity, the object would take 115,000 years to get here.18
Any rock coming from an Earth-sized planet at the comparatively close distance of 40 light years away (or 1/2500th of the diameter of the Milky Way) would take over a million years to get here.
Series of timelapse images showing several of the impacts on the surface of Jupiter by fragments of the Shoemaker-Levy 9 comet. Gaping impact zones, in some cases larger than the earth, were revealed in photographs of the giant gas planet soon after collision.
3. Other problems
“Radiation would destroy DNA on a journey between stars,” says Francis Cucincotta of the NASA Johnson Space Centre in Houston.19 Other hazards would be: the near-absolute-zero temperature of space, without a space suit; the lack of nutrients and/or oxygen in the vacuum of space, without a space vehicle; entry into Earth’s atmosphere, without a heat shield, which has been proven to burn up bacteria20; and impact with planet Earth, without a parachute.
Some idea of the force of such an impact was demonstrated by the catastrophic collision of 20 fragments of Comet Shoemaker-Levy 9 with Jupiter on July 16–22, 1994 (see images to the right).
All in all, interstellar space travel for living organisms is sheer wishful thinking.
There are no biblical or moral reasons why God should not have formed other planets, when He formed those in our own solar system, on Day 4 of Creation Week (Genesis 1:14–19).
Whether there is life on any planet other than Earth is another matter. The Bible teaches that life began on Earth through a process of commanded-by-God creation (Genesis 1:11–27). It also tells us that God’s purposes are centred on Earth. Thus God created Earth (on Day 1) before He created “the lights in the firmament of heaven” (on Day 4), which were “to divide the day from the night” and were “for signs, and for seasons, and for days, and years” (Genesis 1:14), i.e. for the benefit of mankind.
Man and woman were both “made in the likeness of God” (Genesis 1:27). This, coupled with factors such as the Fall, the Incarnation, the redemption of mankind through the once-only death and Resurrection of the Lord Jesus Christ, the Second Coming of Christ to Earth, and the coming Judgment of all mankind, show Earth’s unique importance among the billions of billions of stars in the un