Astronomers have discovered nearly 6,000 planets in the last 20 years. And Neanderthals had red hair and freckles.
We are living in a great age of natural science.
In “On First Looking Into Chapman’s Homer,” John Keats described the wonder he felt on reading the translations of The Iliad and the Odyssey published in 1616 by Shakespeare’s contemporary George Chapman (1559-1634):
Then felt I like some watcher of the skies When a new planet swims into his ken; Or like stout Cortez when with eagle eyes He star’d at the Pacific — and all his men Look’d at each other with a wild surmise — Silent, upon a peak in Darien.
It was Balboa, not Cortes, who was the first Spanish explorer to see the Pacific from Central America (Keats was corrected but let the line stand). The “watcher of the skies” who delights “when a new planet swims into his ken” was the astronomer William Herschel, who discovered Uranus in 1781.
Neptune was discovered in 1846 and Pluto in 1930. In mid-July of this year, the New Horizons space probe flew close to the surface of Pluto, now known to be one of a number of dwarf planets in the outer solar system, including the newly-discovered Eris, Haumea and Makemake. Thanks to the photographs from New Horizons, ours is the first generation to gaze on the surface of Pluto.
If you aren’t as thrilled to be alive and learning something new as Herschel, Balboa and Keats, you aren’t paying attention.
Beyond our solar system, new planets swim into our ken — or rather swarm. In 1992 Aleksander Wolszczan discovered a planet orbiting around a pulsar, the remnant of a supernova. In 1995 the first planet orbiting a normal star was discovered by Michel Mayor and Didier Queloz, a Jupiter-like world called Pegasus 51 b 50 light years away.
In the two decades since 1995, using a variety of techniques, astronomers have discovered thousands of planets orbiting distant suns. As of September 9, 2015, according to NASA’s Jet Propulsion Laboratory, 1,889 planets had been confirmed, out of 5,593 suspected planets.
The easiest planets to identify at first were “hot Jupiters,” gas giants close enough to their stars to perturb their movements. But as planet-finding techniques have advanced, astronomers have discovered smaller and smaller worlds. One surprise has been the number of “super Earths,” intermediate in mass between the Earth and Uranus or Neptune.
Think about it. In 20 years we have learned of the existence of roughly two to six thousand planets in other star systems. We have discovered more worlds in 20 years than in all of prior human history.
Back on earth, this is an age of scientific wonders as well. It is stunning to think that as recently as 12 years ago in 2003 the human genome was completely decoded.
The potential of genetic medicine has yet to be realized. But DNA analysis has already revolutionized our understanding of the human past. It has allowed scientists to infer the existence of an extinct hominid group, the Denisovans, who shared the earth with modern humans and Neanderthals 40 thousand years ago. DNA testing is underway on yet a fourth species, the tiny and mysterious “hobbits” who lived in Indonesia as recently as 12,000 years ago.
Because DNA permits scientists to reconstruct complexions and hair and eye colors, we now know that a male hunter-gatherer who lived in Spain 7,000 years ago had dark skin, dark hair and blue eyes. And the Neanderthals who preceded modern humans in Ice Age Europe had blue or green eyes, red hair, light skin and possibly freckles.
We know the colors of some dinosaurs, too.
In 2010, scientists reconstructed not only the colors (reddish orange and white) but also the pattern (a striped tail) of the fuzzy protofeathers of a carnivorous dinosaur, Sinosaupteryx. Another feathered chicken-like dinosaur, Anchiornis, had gray body plumage, black and white wings and a reddish crest.
Yes, dinosaurs had feathers. We now know that all bipedal, carnivorous dinosaurs were probably feathered. Tyrannosaurus Rex looked more like Big Bird than Fafnir the Dragon.
Amazing.
Is this a Golden Age of natural science? Arguably not. As rich in wonders as it is, today’s era of discovery cannot compare to the nineteenth and early twentieth centuries. The legacies of that epoch include Darwin’s theory of evolution by natural selection and the later discovery of DNA and RNA, Einstein’s theory of relativity, the discovery of the expanding universe and the Big Bang , the discovery of the sequence of life on earth from bacteria through the dinosaurs to hominids.
If it is not a Golden Age, our time is at least a Silver Age of natural science. Scientists are filling in the details of the big picture of the origins of the universe, life and humanity that was provided by the discoverers and geniuses of the preceding era. In an otherwise dreary period characterized by global economic stagnation and political dysfunction, we can take delight in the marvels revealed by science almost every day.
Did I mention that Neanderthals had red hair and freckles? •