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of other stars； absence of evidence had been considered evidence of absence。
Today we have firm evidence for at least three planets orbiting an extremely dense star； the pulsar designated B1257＋12； about which I'll say more later。 And we've found； for more than half the stars with masses like the Sun's； that early in their careers they're surrounded by great disks of gas aid dust out of which planets seem to form。 Other planetary systems now look to be a cosmic monplace； maybe even worlds something like the Earth。 We should be able； in the next few decades； to inventory at least the larger planets； if they exist； of hundreds of nearby stars。
Well； if our position in space doesn't reveal our special role； our position in time does： We've been in the Universe since The Beginning （give or take a few days）。 We've been given special responsibilities by the Creator。 It once seemed very reasonable to think of the Universe as beginning just a little before our collective memory is obscured by the passage of time and the illiteracy of our ancestors。 Generally speaking； that's hundreds or thousands of years ago。 Religions that purport to describe the origin of the Universe often specify—implicitly or explicitly—a date of origin of roughly such vintage； a birthday for the world。
If you add up all the 〃begats〃 in Genesis； for example； you get an age for the Earth： 6；000 years old； plus or minus a little。 The universe is said to be exactly as old as the Earth。 This is still the standard of Jewish； Christian； and Moslem fundamentalists and is clearly reflected in the Jewish calendar。
But so young a Universe raises an awkward question： How is it that there are astronomical objects more than 6；000 light…years away？ It takes light a year to travel a light…year； 10；000 years to travel 10；000 light…years； and so on。 When we look at the center of the Milky Way Galaxy； the light we see left its source 30；000 years ago。 The nearest spiral galaxy like our own； M31 in the constellation Andromeda； is 2 million light…years away； so we are seeing it as it was when the light from it set out on its long journey to Earth—2 million years ago。 And when we observe distant quasars 5 billion light…years away； we are seeing them as they were 5 billion years ago； before the Earth was formed。 （They are； almost certainly； very different today。）
If； despite this； we were to accept the literal truth of such religious books； how could we reconcile the data？ The only plausible conclusion； I think； is that God recently made all the photons of light arriving on the Earth in such a coherent format as to mislead generations of astronomers into the misapprehension that there are such things as galaxies and quasars； and intentionally driving them to the spurious conclusion that the Universe is vast and old。 This is such a malevolent theology I still have difficulty believing that anyone； no matter how devoted to the divine inspiration of any religious book； could seriously entertain it。
Beyond this； the radioactive dating of rocks； the abundance of impact craters on many worlds； the evolution of the stars； and the expansion of the Universe each provides pelling and independent evidence that our Universe is many billions of years old—despite the confident assertions of revered theologians that a world so old directly contradicts the word of God； and that at any rate information on the antiquity of the world is inaccessible except to faith。 These lines of evidence； as well； would have to be manufactured by a deceptive and malicious deity—unless the world is much older than the literalists in the Judeo…Christian…Islamic religion suppose。 Of course； no such problem arises for those many religious people who treat the Bible and the Qur'an as historical and moral guides and great literature； but who recognize that the perspective of these scriptures on the natural world reflects the rudimentary science of the time in which they were written。
Ages rolled by before the Earth began。 More ages will run their course before it is destroyed。 A distinction needs to be drawn between how old the Earth is （around 4。5 billion years） and how old the Universe is （about 15 billion years since the Big Bang）。 The immense interval of time between the origin of the Universe and our epoch was two…thirds over before the Earth came to be。 Some stars and planetary systems are billions of years younger； others billions of years older。 But in Genesis； chapter 1； verse 1； the Universe and the Earth are created on the same day。 The Hindu…Buddhist…Jain religion tends not to confound the two events。
As for humans； we're lateers。 We appear in the last instant of cosmic time。 The history of the Universe till now was 99。998 percent over before our species arrived on the scene。 In that vast sweep of aeons； we could not have assumed any special responsibilities for our planet； or life； or anything else。 We were not here。
Well； if we can't find anything special about our position or our epoch； maybe there's something special about our motion。 Newton and all the other great classical physicists held that the velocity of the Earth in space constituted a 〃privileged frame of reference。〃 That's actually what it was called。 Albert Einstein； a keen critic of prejudice and privilege all his life； considered this 〃absolute〃 physics a remnant of an increasingly discredited Earth chauvinism。 It seemed to him that the laws of Nature must be the same no matter what the velocity or frame of reference of the observer。 With this as his starting point； he developed the Special Theory of Relativity。 Its consequences are bizarre； counter intuitive； and grossly contradict mon sense—but only at very high speeds。 Careful and repeated observations show that his justly celebrated theory is an accurate description of how the world is made。 Our monsense intuitions can be mistaken。 Our preferences don't count。 We do not live in a privileged reference frame。
One consequence of special relativity is time dilation—the slowing down of time as the observer approaches light speed。 You can still find claims that time dilation applies to watches and elementary particles—and； presumably； to circadian and other