ACCIDENTAL ASTRONOMY

An astrophysicist examines why “we exist as the result of a chain of countless accidents.”

Having written a popular account of his subject in Bang! The Complete History of the Universe, Lintott, professor of astrophysics at Oxford, writes another that steps back to remind readers that, until the past century and with the exception of the Earth, astronomers dealt with subjects that were out of reach. Unable to perform experiments, they attempted to explain what they saw with a confidence that was not always justified, and they regularly changed their minds. “Whenever we have looked longer, deeper, farther or in new ways at the Universe, it has surprised us,” writes the author. In reality, the surprises are almost always phenomena that were there all the time. Perhaps the most unwelcome would be one of the roughly 800,000 known asteroids striking the Earth. About 20,000 cross our orbit, with plenty of experts tracking their progress. They assure us that a disastrous collision is guaranteed, if unlikely—similar to the odds of dying in a plane crash. Discovery of the first planets around other stars produced headlines, but it’s now clear that uncounted numbers exist. That surprise is sure to be dwarfed by the first evidence of life beyond Earth. Being alive requires so many wildly complex processes that life’s development on Earth may be unique, although this is a minority view. Most astronomers believe that life is inevitable given certain conditions, and the presence of billions of earthlike planets in our galaxy alone gives cause for hope. Enthusiasts may gnash their teeth at Lintott’s lack of interest in UFOs and insistence that hard evidence for alien life forms is nonexistent, but he is a diligent scientist, and the discovery of a single one will convince experts that the universe is well populated.

An entertaining astronomical miscellany.