Taking a break from its focus on the upcoming solar eclipse, Lowell Observatory, of Flagstaff, Arizona, sent its director, Jeff Hall, to Madras last week to discuss the universe.
Hall, who will return to Madras for the Aug. 21 total solar eclipse, along with 14 other staff members, 65 volunteers, and about 300 donors, gave a talk on "Are We Alone in the Universe?" to a crowd of about 125 people at the Madras Performing Arts Center.
"We're really privileged today," said Hall. "We're the first generation able to answer ... Are there other worlds out there? Might there be other planets?"
The solar system, which consists of at least eight planets orbiting the sun, is located in the Milky Way Galaxy, which has about 200 billion stars.
"Sagittarius is at the very center of our galaxy," said Hall. "I was able to see it flying in last night."
The number of planets in the solar system became controversial in 2006, when the International Astronomical Union demoted Pluto from a planet to a "dwarf planet." There are the shoo-in planets: the terrestrial planets Mercury, Venus, Earth and Mars; the giants, Jupiter, Uranus, Saturn and Neptune; and then there is Pluto.
"Our sun has, I'm just going to say it, nine planets," said Hall, who still considers Pluto, and the other dwarf planets as bonafide planets. Pluto was discovered by Clyde Tombaugh in 1930, at Lowell Observatory, but that's not why Hall believes it should remain a planet.
The definition of a planet specifies that "a planet orbits the sun, and is big enough to be a bully; it plows everything out of its way," he said.
According to the International Astronomical Union, a planet must be a celestial body in orbit around the sun, have enough mass for its "self-gravity to overcome rigid body forces" to make it nearly round, and it must clear the neighborhood around its orbit. Dwarf planets align with the first part of the definition, but are not large enough to have "cleared the neighborhood."
By that definition, he said, the Earth's status could be questioned, since it failed to stop a large meteorite from hitting Chelyabinsk, Russia, in 2013.
"I and many others think the 'clear the orbit' part of the definition is silly. Proponents will say that they're not really referring to very small chunks of rock, such as the one that exploded over Chelyabinsk, but just larger stuff," he noted. "But it's still a bad component, since (for example) if you teleported Earth out to where Pluto is, it would no longer be a planet. Once it kicked all the objects out of its new orbit, it would suddenly become a planet again."
"I also think tying the definition to objects in the solar system is silly," Hall said. "We're finding very similar objects around hundreds of other stars — are they not planets? Making a scientific classification location-based is not a good way to do it."
In 2009, NASA launched the Kepler space observatory to focus on one spot in the sky, he said. As of June, the Kepler mission had discovered 4,034 planet candidates and 2,335 confirmed planets in orbit around many different stars.
Asked whether or not there is other life in the universe, Hall said, "The honest, purely scientific answer is 'I don't know.' We have no direct evidence of life elsewhere in the universe, so, I don't know."
"That said, I think that given the number of planets that seem to be out there, and that quite a few of them must be Earth-like (in the sense that they're more or less Earth-sized, and are neither infernos nor frozen wastelands), it is probable there indeed is life elsewhere — perhaps it's just very simple, but life nevertheless," he said.
"There might even be some elsewhere in our solar system," said Hall. "But we have yet to confirm that. If we do, it would be a momentous discovery."
A native of Virginia, Hall has worked at Lowell Observatory since 1992, and became the director in 2010. He earned his undergraduate degree in physics from Johns Hopkins University in 1986, and his doctorate in astronomy and astrophysics in 1991 from Pennsylvania State University.
Solar eclipse plans
Regarding the Aug. 21 solar eclipse, Hall said that a partial eclipse will be visible across the entire U.S., but the path of totality is only about 70 miles across. Madras sits very near the center of totality, which makes it a prime location for viewing the total eclipse.
"It's an extraordinary thing to see," said Hall, who will be back at the PAC Aug. 20, for the start of the Lowell Observatory Solar Eclipse Experience, which will include presentations by astronomers, a star party, and a giveaway of 10,000 pairs of eclipse glasses.
Hall will present "What to Expect When You're Expecting an Eclipse" at 6 p.m., Sunday, Aug. 20, and again at 7 a.m., Monday, Aug. 21. Sunday's events are free, and open to the public; tickets for Monday's events at the PAC and Madras High School football field cost $20, and includes a pair of solar glasses. Visit www.lowellsolareclipse.com to find out more, or purchase a ticket.
For those who are not in the path of totality, which in Central Oregon, includes Bend, Hall recommends making the effort to experience the total solar eclipse.
"Even if it's 80 percent covered, it's not that impressive," he said. "It's a little cooler, the light's lower, and it's a little duskier."
Hall stressed that viewers cannot use regular sunglasses, which are not safe for looking at the sun. To avoid damaging your eyes, eclipse glasses, which have an ISO 12312-2 certification, must be worn when looking at the sun, except during the 2 minutes and 2 seconds of totality.
During totality, viewers should remove their glasses. "You want that whole visceral experience," he said.