September 29, 2016

Gorge night sky symposium sparks good lighting conversations

A diverse group of night-sky enthusiasts, business people, lighting designers, and government officials gathered last month in Goldendale, Washington and The Dalles, Oregon for a two-day symposium for discussion of measures that might be taken to protect the supremely dark night skies in the Columbia River Gorge. While Seattle Astronomy was unable to attend because of travel, we did speak recently with symposium organizer Jonathan Lewis, who said the event was a big success because it got some great conversations started.

LEDs can be good

The Goldendale Observatory was one of the sites for a
two-day symposium about dark skies in the Columbia
River Gorge. Photo: Greg Scheiderer.
Notably, Lewis said that author Paul Bogard portrayed LED lighting as the enemy during his keynote talk to open the symposium, but participants were able to change some minds.

“By the end of it we realized that the LED technology has a lot of potential to make the dark skies much better if it’s done properly,” Lewis said. “That was really the goal, to get that message out.”

Lewis gave several examples of talks that were learning experiences for symposium attendees. Gary Chittim of a lighting company called PlanLED discussed human-centric lighting that takes into account our circadian rhythms and other factors. LED lighting can be turned down low in the evening and much hotter during the day to mimic the Sun.

“Our relationship with lighting can, with LEDs, mimic a more natural environment, not only at night but also during the day,” Lewis noted.

Another speaker, Rob Leonard of Echelon, demonstrated interesting possibilities for the control of LEDs to provide as much light as needed when it is needed. LEDs can be set to dim at certain hours, and to get brighter only when people move near them. There’s even an app with an emergency button that can allow a person to turn up the lights if they’re concerned they’re being stalked at night.
“Amazing sci-fi stuff that they have available right now,” Lewis said, adding that Echelon is helping to put in controlled lights in Goldendale.

Lighting the ballfield

Sports teams have been among the loudest objectors when strong lighting ordinances are suggested, but Leonard also talked about arena lighting, and said that sports stadia can now be lit more evenly with minimal glare or light trespass.

“All of those things are greatly improved with the newer LED technology that’s available, so a lot of the arguments that sports groups might have against lighting ordinances maybe will go away because of the new technology,” Lewis said.

Building political support

Most of the “right people” attended the symposium, according to Lewis, including officials from Wasco County in Oregon, city commissioners from Hood River, and representatives from Columbia Gorge Scenic Area groups. State Rep. Gina McCabe (R-Goldendale) attended and stated that the attraction of the dark skies is important for tourism in the area.

“She’s definitely a leader in the business community, and having the businesses hear what she had to say and to have that be an important part of her agenda was really important,” Lewis said. He’s hoping McCabe can help engage on some statewide issues. For example, sometimes lighting ordinances aren’t enforced adequately in smaller communities because they don’t have their own electrical inspectors and rely instead on state inspectors through the Department of Labor and Industries. State legislation could allow L&I inspectors to enforce or urge compliance with local ordinances even though they serve different jurisdictions.

“Some conversations like that were able to get started,” Lewis said.

The conversations are continuing, Lewis said. There’s some talk about creating a Gorge-wide dark sky area project, which he called, “a very exciting possibility.” There’s also a movement afoot to start collecting data about light levels in the Gorge. Lewis noted that people who wish to follow these efforts can sign up for newsletters from the Mid-Columbia Economic Development District and the Friends of the Goldendale Observatory.

If you missed the symposium as we did, you’ll find videos of the various presentations below.

Videos of presentations from the dark-sky symposium:













September 27, 2016

Total solar eclipse 2017: Salem, Oregon

This is the tenth article Seattle Astronomy has done to preview possible places from which to view the total solar eclipse that will cross the United States next August 21. We’ve talked with folks from Madras, Oregon to Columbia, South Carolina and points in between. It’s time to look at the closest viewpoint for Seattle eclipse chasers: The Salem Fairgrounds in Salem, Oregon are just 219 miles from Seattle Astronomy world headquarters, and will be the site of an eclipse viewing party headed by the Oregon Museum of Science and Industry (OMSI.)

Good viewing in Oregon

“Oregon is really advertised as the best place to view the eclipse, and we’re expecting ten million visitors to come down to Oregon for that one-day event,” said Jim Todd, director of space science education at OMSI. “Oregon needs to be ready.”

That latter is something of an understatement. Todd says they expect about ten thousand people to attend the OMSI-sponsored party at the fairgrounds, an event that has support from Rose City Astronomers in Portland, the Oregon Observatory, and NASA, among others. The party will feature science lectures, astronomy-related community groups, and entertainment, including a performance by the Portland Taiko drum ensemble.

Salem is a bit north of the center line of totality, which crosses I-5 about halfway between Oregon’s capitol city and Albany. But the total eclipse will last nearly two minutes at the fairgrounds, and Todd said there will be numerous other viewing points in and near the city, including at Willamette University and Volcano Stadium in Keiser, where the Salem-Keiser Volcanoes baseball team, a class-A affiliate of the San Francisco Giants, are planning a Monday morning baseball game for next August 21 that may feature the first “eclipse delay” in the history of organized ball.

“It goes without saying: we can’t do this alone,” Todd said. “We just have to educate the public and make sure they understand what’s involved with the eclipse.”

Western Oregon eclipse map courtesy GreatAmerican Eclipse.com.
They’re doing that through planetarium shows, workshops, and social media to get the word out, especially about about safe viewing of the eclipse during its partial phase. They’ve also been in touch with government officials from the Oregon governor’s office on down to make sure they’re thinking ahead for eclipse day. With huge crowds expected, things could get chaotic, especially if there are clouds around and people have to scramble to find a clear sky for the moment of the eclipse.

“It will likely be hot, it will likely be crazy as far as traffic jams. Airports, hotels, you name it,” Todd warns. “It’s going to be a crazy day. It’s going to be one of those days people are going to remember where they were on that very day when they were looking for the eclipse.”

Rural options

Todd also serves as a co-director of the annual Oregon Star Party, which has set its 2017 event for the days before, of, and after the eclipse.

“We plan to do viewing from Indian Trail Spring in the Ochoco Mountains,” he noted. The site is somewhat south of the center line of the path of totality, and will enjoy about a minute and 27 seconds of total solar eclipse.

One concern about eclipse day is that many people will simply head for similar remote areas and gridlock roads there.

Jim Todd. Photo: LinkedIn.
Todd has seen one other total solar eclipse, that back in 1979. He was a senior in high school and had to wrangle his way around official authority to do it.

“My science teacher was going to keep the class inside,” he recalls with a laugh. He got permission to head to Goldendale, Washington with another family, where they escaped cloudy Portland skies—it was February—and saw the eclipse. Next year may be a bit easier.

“Fortunately for us [the eclipse is] going to be in August, when we have a great chance of clear skies,” Todd noted.

The job fits

Todd is a true space nut. Like many of us, his interest was cemented when he watched Apollo 11 land on the Moon. He taught himself space science and astronomy, then took an internship at OMSI. He never left; he’s been there 33 years.

“It’s been my way of getting close to NASA by getting close to all of the astronomical events,” he said. “It’s one of the very few jobs where the hobby has actually become the job. I was able to combine my passion with astronomy and space science with the teaching and computers and so on. It was a perfect fit.”

Portland is an astronomy city. Rose City Astronomers is one of the biggest clubs in the country. Proximity to pretty good dark, transparent skies may be one reason for that.

“Portland has a science-minded audience and they love these kind of events,” Todd said. “We like to think, too, that OMSI had a role in that.”

Tickets to the eclipse party at Salem Fairgrounds are $8 and are available now through the OMSI website.

September 13, 2016

Proxima Centauri b and the question of habitability

The discovery of evidence of a planet in orbit around our nearest stellar neighbor, Proxima Centauri, has people all agog and with good reason. It’s something of a misnomer, however, to call the exoplanet Proxima Centauri b “Earth-like.” Rory Barnes, a professor in the Department of Astronomy and the Astrobiology Program at the University of Washington, points out that the planet’s mass is probably somewhere between 1.3 and five times that of Earth.

UW prof. Rory Barnes speaking at an Astronomy on
Tap Seattle event earlier this year. Photo: Greg Scheiderer.
“There’s a lot of excitement about this planet because it is so close in mass to the Earth, but we don’t actually know if it’s even rocky like the Earth,” said Barnes during a recent talk at the Pacific Science Center. Barnes, who uses computer modeling to study the habitability of exoplanets, noted that even though Proxima Centauri is the next closest star, it’s still pretty far away at 4.24 light years. If the Sun were the size of a baseball resting on home plate at Safeco Field, Barnes said Proxima Centauri b would be a grain of sand in New York City. Still, he noted there’s understandable excitement about the discovery.

“The reason why I think that this is the biggest exoplanet discovery since the discovery of exoplanets is because it is still very close, at least relatively speaking,” Barnes said. “We really have a chance, with this planet, to potentially observe its atmosphere and its surface and maybe start to try and sniff out the presence of life on that planet. Or not. We don’t know yet. But being so close, it gives us a shot.”

Not really “like” Earth

While Proxima Centauri b is about the mass of Earth, plenty else is different. It’s twenty times closer to its home star than Earth is to the Sun, and goes around that star in just 11.2 days. We know little else about it. The star has just 12 percent of the mass and 14 percent the radius of the Sun, and its brightness is just one one-thousandth that of the Sun.

“This is a small, dim star,” Barnes said.

Is there life there?

Life requires energy, some bioessential elements, and liquid water. The energy and elements are abundant in the universe, so Barnes says the key to finding life elsewhere is liquid water.

“When we think about exoplanets, we’re really going to focus, at least for now, on surface water,” Barnes said. “Not only is it going to be easier to see, but it’s going to be more similar to the Earth and that gives us a better shot at maybe being able to interpret the observations that we’re going to get.”

The desire to find liquid surface water on a planet led us to the concept of the “habitable zone” around a star, an area where the temperature would be right for liquid water to exist. Barnes said Proxima Centauri b is smack in the middle of the habitable zone.

“This is a dream planet for those of us who study this field,” he said, but added a caveat: “Being in the habitable zone does not mean you’re habitable. It is just the first step we need to get to.”

“The habitable zone is jargon, and it’s really misleading,” Barnes added. “I apologize for my field for inflicting it on you!”

Barnes said there are several threats to habitability for planets orbiting M dwarf stars like Proxima Centauri. With the habitable zone so close to the star, there is potential that stellar flares could blow away the atmosphere of a planet within it. Planets that close are probably tidally locked, too, but this isn’t a deal-breaker; their atmospheres might distribute heat and energy effectively. Tidal heating could cause problematic volcanism.

Barnes showed this chart demonstrating that while
Proxima Centauri b is now within the habitable zone, the
zone was once much further from the star.
The biggest threat to the habitability of Proxima Centauri b, according to Barnes, is that its star was once much bigger and brighter before it contracted into the dim, red phase it is in today. In the early years that would have meant that its habitable zone was out at a distance between .25 and .5 astronomical units, while Proxima Centauri b orbits at a mere .05 AU. Being so far inside the habitable zone after formation means that the planet could have lost all of its water and become a completely uninhabitable place like Venus. On the other hand, if Proxima Centauri b formed as something like Neptune, being so close to the star could have blasted away its hydrogen envelope.

“Maybe that planet could have actually transformed from an uninhabitable Neptune-like planet into a rocky planet like the Earth,” Barnes speculated. “This is what we at the University of Washington think is probably the best bet for how this planet could be habitable.”

Barnes is hopeful that the discovery of Proxima Centauri b will help boost support for the sorts of telescopes and observatories that can make the observations needed to learn more about this intriguing exoplanet and determine if it is habitable, and even inhabited.

While Barnes won’t give the odds of life there—there are way too many variables and so little we know right now—he sounds confident that we’ll find life somewhere. He noted that we’ve found life on Earth in the deep sea, extreme deserts, extreme cold, acidic environments, and under other harsh conditions.

“The realization that extreme life is everywhere is part of the astrobiological revolution that is occurring right now in science,” Barnes said. “This recognition that life finds a way gives us confidence as we go forward.”