Find Uranus on Alki

While walking along Alki Avenue in West Seattle today I encountered the planet Uranus. Not the actual planet—that would create some unpleasant conditions—but an artist’s representation that is part of a scale model of the solar system created by kids at the Three Dragons Academy, an arts-based alternative for elementary-age children.

This sandwich board along Alki Avenue
SW marks the location of Uranus in the
 scale model of the solar system created by
students at Three Dragons Academy. Their
Sun, 18 feet in diameter, is outside the
University Heights Center 7.3 miles
away. Photo: Greg Scheiderer.

Last month the students, aged five through 10, studied painting and scale. This city-wide art installation is the result of their work. The Sun is an 18-foot circle painted and chalked onto the south plaza of the University Heights Center at NE 50th Street and Brooklyn Avenue NE. At that scale Uranus is about eight inches in diameter, and is at 58th Avenue SW and Alki Avenue SW, in front of Coastal Surf Boutique, across the street from Duke’s Chowder House, and just a block away from Astro Biz Blue Moon Burgers. That places Uranus about 7.3 miles from the Sun as the crow flies, at least according to the Google Maps measuring tool. The scale of the model solar system is about 1:253,718,000.

At that scale Mercury, just three-quarters of an inch in diameter, is a mere six blocks away from the Sun at 50th and Roosevelt. All of the other planets are represented, too, and, bless them, the students have even included some dwarf planets. There are a couple of one-third-inch Plutos out there, one up at Paine Field in Everett and the other in Des Moines. Ceres is on the University of Washington campus, fittingly enough near the Physics/Astronomy Building.

They’re already at work on figuring out the recently speculated upon Planet Nine, which is thought to have a highly irregular orbit. At its closest might be around Portland and at its furthest somewhere near Missoula, Montana. They’re not planning to make that trip to place a painting!

You can read more about the project on the Three Dragons Academy website and probably find a planet near you. Visit one or visit them all!

Mr. Eclipse says west may be best for 2017 total solar eclipse

Fred Espenak has earned the moniker “Mr. Eclipse” though almost 46 years of observing, predicting, and chronicling solar and lunar eclipses. Espenak spoke about The Great American Total Solar Eclipse, which will cross the United States in August 2017, during his keynote talk Saturday, Jan. 30 at the annual banquet of the Seattle Astronomical Society.

Fred Espenak, known as “Mr. Eclipse,”
gave tips during a talk at the annual
banquet of the Seattle Astronomical Society
for viewing the August 2017 total
solar eclipse. Photo: Greg Scheiderer.

Espenak retired in 2009 after a long career as the head eclipse guy at NASA, where he maintained the agency’s eclipse information pages. His photography of eclipses has appeared in numerous magazines, and he’s often tapped by the news media to provide expert commentary about eclipses. He’s had a hand in several books about the topic.

Espenak was bitten by the eclipse bug when he was in high school. He had just gotten his driver’s license and went on a 600-mile road trip to watch and photograph a total solar eclipse from Windsor, North Carolina in March 1970.

“I was overwhelmed by the experience,” Espenak said. “It was like nothing I had read in the books. The spectacle of totality just cannot easily be conveyed through books, through writing, through photographs, through video.”

The total solar eclipse that will happen on August 21, 2017 will be the first one visible from the continental United States since 1979. We’re lucky to live in the Northwest because some of the best odds for clear weather for the event are close by. That’s not the sort of sentence we write often on Seattle Astronomy.

Madras in August

“In Madras, Oregon the prospects there are 35 percent [cloudiness] from satellite data and 24 percent probability of clouds from the nearest airport,” Espenak said. “Madras is favored with probably the best long-term climate along the entire eclipse path, and that’s why a lot of people are heading in that area.”

Madras is about 45 miles north of Bend in central Oregon.

Espenak and eclipsing partner Jay Anderson have done some exhaustive analysis of the 2,500-mile path the total eclipse will take across twelve states from Lincoln City, Oregon to Charleston, South Carolina. Anderson crunched weather data from satellite photos and airport reports and found that, in general, our chances are better out west. The midwest is prone to thunderstorms in the summer and the east coast can get clouds because of moist air from the Gulf of Mexico and the Atlantic. But Espenak cautions about relying too heavily on history.

Where to see the eclipse

“I can’t tell you the magic place where the best weather is going to be,” he said. “All of these statistics that Jay has concocted and derived are based on climate and 20-year studies.”

“On eclipse day you don’t get climate, you get weather,” Espenak added. While he has no magic spot, Espenak plans to start his personal pursuit of the 2017 eclipse in Casper, Wyoming, which is near the center of the eclipse path and has pretty good weather prospects.

“Casper is the location where the Astronomical League will hold its 2017 annual conference, and of course that’s going to bring a lot of eclipse chasers there,” Espenak explained. “That’s also what will bring me there, the conference. But I’m not saying I’m necessarily going to watch the eclipse from Casper, because it depends on what the two-day weather forecast is before eclipse day. If the weather looks good, I’ll stay there. If not, I’m prepared to run.”

That is Espenak’s most important piece of advice. As with real estate, when it comes to total solar eclipses, location is everything.

“Mobility, mobility, mobility is the key to seeing the eclipse, especially in this day and age with the wonderful weather forecasts you can get 24 to 48 hours in advance,” he said. “The biggest thing to keep in mind is if some large frontal system is moving across the United States, because that’s going to be the exception to the rule that throws these weather statistics out the window. That’s what’s going to change everything. If there’s a big front coming through, you want to look at the forecasts and make sure that you are on the dry side and clear side of that front at your location on eclipse day.”

That might mean you have to drive hundreds of miles to get a view of the Sun on eclipse day. Espenak said just do it if you have to.

“It’s worth it to see the total eclipse,” he said. “It’s the most spectacular thing you will probably ever see with the naked eye.”

Don’t miss this eclipse

After a long drought, it’s interesting to note that another total solar eclipse will be visible from the United States in 2024. But Espenak cautioned that this is no reason to bail on next year’s event because of a cloud or two.

“You really need to take every opportunity, because you never know what hand you’re going to be dealt in terms of weather,” he said, noting that, even with all of the data available and his experience chasing eclipses, about a quarter to a third of the time the weather leads to disappointment.

“It’s just a fact of the game,” he said.

More resources

• Espenak’s interactive Google Map with eclipse times and other data for every point along the eclipse path
• Mr. Eclipse, Espenak’s website about eclipse photography
• Eclipsewise, Espenak’s site of chronicles and predictions of eclipses
• GreatAmericanEclipse.com with maps galore, history, gear, and more
• Eclipsophile: Jay Anderson’s site for eclipse weather information
• Eclipse2017.org: Dan McGlaun’s site with information on each community in the eclipse path
• Skippysky.com.au, with predictions of cloud cover
• NationalEclipse.com, another comprehensive site for eclipse info and gear

Books by Fred Espenak

Radioactivity is good for you

While most of us tend to think that radioactivity is dangerous, experts say that, like beer, it’s actually good for you in moderation. We learned this while drinking radioactive beer at Bad Jimmy’s Brewing Company in Ballard on Wednesday during the “radioactive edition” of Astronomy on Tap Seattle.

Radioactive beer

UW prof. Rory Barnes makes a point about radioactive beer
during his Astronomy on Tap talk at Bad Jimmy’s Brewing
Company on Wednesday, Jan. 20, 2016. Photo: Greg Scheiderer.

University of Washington astrobiology professor Rory Barnes did the math on the beer. Figuring that a pint is about 90 percent water, carbon is about ten percent of the rest. That works out to 4.5 grams, or about 200 billion carbon-14 atoms. Carbon-14 has a half-life of 5,730 years, which Barnes said means that, in your glass, there’s about one atomic decay every second.

“You are all drinking radioactive beer,” he said. Nobody stopped. I was sipping on a red IPA which was delightful and may have been even a bit more radioactive than the others!

Barnes noted that while we think of Chernobyl or Fukushima when we think about radiation, the process of radioactive decay is pretty important.

Radioactivity is good

“If it weren’t for the radioactivity inside our planet we’d all be dead,” he said. Barnes explained that decay of uranium, thorium, and potassium inside the Earth produces about 50 terawatts of energy, or about 0.1 watt per square meter on the surface. That much energy could run our entire civilization if we could capture it. As it is, it drives geologic processes such as plate tectonics, which helps regulate the amount of carbon dioxide in our atmosphere.

“It’s really important that the planet does a good job of keeping it from building up to too high of a level or dropping down to too low of a level because then our Earth would not be habitable,” Barnes explained. “Without (plate tectonics) the carbon dioxide would either build up and our planet would roast or it would get drawn down and our planet would freeze.”

Earth is in a sweet spot as far as this internal energy goes. Mars generates less than half the energy Earth does and is geologically dead. Jupiter’s moon Io generates a whopping two watts per square meter and is wildly active volcanically. For life, conditions have to be just right.

Radioactivity may lead us to ET

Barnes said that this fact could help guide us to other planets that might be likely to harbor life. The trouble is that in order to determine a planet’s internal energy and radioactivity we would have to look inside a rock that is hundreds of light years away.

“It’s not really obvious how you do that, but that’s what we need to do,” he said. “I’m sorry to say that the answer is that we can’t at this point. This is the limit of our scientific research right now.”

The James Webb Space Telescope will be able to determine the elements in the atmospheres of distant planets. Barnes said it would make sense to use JWST to look at planets that are near where supernovae have occurred, because these stellar explosions spread the heavy elements needed for this sort of planetary energy generation.

Radioactivity and the ages of stars

UW postdoctoral research associate Charli
Sakari explains how the age of a star can
be determined by the presence of radioactive
elements. Photo: Greg Scheiderer.

UW astronomy post-doc Charli Sakari also uses radioactivity in her work. During her Astronomy on Tap talk she explained how she determines the makeup of stars by looking at spectra of the light they emit. Different elements leave a clear signature in the spectrum, absorption lines created when atoms in a star’s atmosphere absorb certain color wavelengths.

“If we measure how dark those lines are we can figure out how much of those elements is present in the atmospheres,” Sakari said.

It is especially informative to look for uranium and thorium.
“Uranium-238 has a half-life of 4.5 billion years, which is about the age of the Sun, whereas thorium-232 has a half life of 14 billion years,” Sakari explained. “These half-lives are long enough that we can use them to date the ages of the oldest stars in the universe.”

The oldest stars have few elements heavier than helium. Younger stars can contain many heavier elements fused in the cores of the generations of stars that preceded them.

Astronomy on Tap Seattle drew a big crowd to Bad Jimmy’s on a rainy Wednesday night. In fact astronomy and beer lovers were packed in so tightly, and were generating considerable warmth, that the staff popped the garage-type doors open to let in a little fresh air. One wag in the crowd speculated that the robust attendance may have been an indicator of the sorry state of network television. We would say that, in eleven months of events Astronomy on Tap, which is organized by astronomy graduate students at the UW, has delivered plenty of good information and tons of fun. The next gathering is scheduled for Feb. 24.

Science and art meet in Silent Sky at Taproot Theatre

We love it when science and art meet, and its going to happen this month when Lauren Gunderson’s play Silent Sky, directed by Karen Lund, has its Northwest premiere from Jan. 27 through Feb. 27 at Taproot Theatre in Greenwood.

Silent Sky is the true story of Henrietta Leavitt, the American astronomer who discovered the relationship between the luminosity and the period of Cepheid variable stars. Her work at Harvard College Observatory received little attention during her lifetime, which spanned 1868–1921, but her discovery was the key to our ability to accurately determine the distances to faraway galaxies. Silent Sky plays out against a landscape of fierce sisterly love, early feminism, universe-revealing science, and a time when humans were called “computers.”

Lauren Gunderson

Gunderson is a marvelous playwright who lives in the San Francisco Bay Area. We have seen several of her other plays, including Émilie: La Marquise Du Châtelet Defends Her Life Tonight, the fascinating tale of Émilie Du Châtelet, the 18th-Century French physicist who not only translated Newton’s Principia Mathematica but also made profound contributions in fine-tuning Newtonian mechanics. Émilie usually bested Voltaire, one of her lovers, in battles of wits. We reviewed the 2011 production at ArtsWest in West Seattle and enjoyed it immensely. Silent Sky promises to be entertaining and enlightening as well. The cast includes Hana Lass, an outstanding local actor, in the title role.
Tickets to Silent Sky are available online.

State House committee considers curb of light pollution

Rep. Jessyn Farrell

When a bill aimed at curbing light pollution in the State of Washington received a hearing before the House Environment Committee yesterday in Olympia it was the first formal discussion of the topic at the state level in seven years. House Bill 2057 would direct the state Department of Ecology to assess the environmental, economic, and public health effects of light pollution, and to submit the study and policy recommendations for reducing light pollution to the Legislature by next January.

Rep. Jessyn Farrell, D-Seattle, is the prime sponsor of the legislation.

“This is a really important issue,” Farrell said. “There are lots of studies that do show that there is an impact on human health, the natural environment, property values” from light pollution. “The goal here is to study this and see what the current state of that research is.”

Amateur astronomers testify

Farrell said the issue was brought to her by a constituent, David Dorais, who in testimony before the committee described himself as, “a former traffic engineer who knows something about outdoor lighting, especially for street use and safety. As a lifelong amateur astronomer I also know something about how we can do a much better job of illuminating those places throughout the state that need the banishment of the dark.”

L-R: David Dorais, Qiu Min Ji, and David Ingram testified
in favor of HB 2057 at a hearing of the state House
 Environment Committee on Jan. 12, 2016. Photo: Greg Scheiderer.

David Ingram, a volunteer who heads up Dark Skies Northwest, the local chapter of the International Dark-Sky Association, called the night sky a natural resource and a wonderment.

“It has inspired architecture, religion, philosophy, science and technology,” Ingram testified. “I don’t know how our young people are going to be similarly inspired if more than half of them don’t even have a contact with the night sky.”

“It’s of vital importance that we look at the question of what happens to the soul of men and women when they’re removed from contact with the night sky,” Ingram said. He added that he doesn’t want to go back to the dark ages, but believes we have the technology to use light to enhance safety, wayfinding, and commerce efficiently and effectively, without blotting out all of the stars in the process.

Amendments likely

There will probably be some changes to the bill before the committee votes on it. Jessica Archer, who is with the scientific arm of the Department of Ecology, suggested that the departments of Health, Fish and Wildlife, and Commerce be brought in on the study, as Ecology lacks the expertise to weigh in on light pollution’s impact on animals, human health, or property values. Archer also suggested that the scope of the study be more clearly spelled out, which will also help them determine the cost of the effort. Farrell said that she might seek to add potential cost savings to the scope of the study. It’s also possible that the deadline for the study will be pushed out; the due date of January 1, 2017 was set when the bill was first drafted last year.

Farrell noted that HB 2057 takes a far more cautious approach than did fairly comprehensive and directive light pollution legislation that was considered in 2008 and 2009. Mark Johnson, representing the Washington Retail Association, testified that his organization wanted to make sure that any consideration of light pollution didn’t have an adverse impact on safety or business. That’s a reason why Farrell went with a deliberate approach.

“I think we should study this and see if there’s further action that we should take,” she said.

Next steps

The bill must gain the approval of the committee by Feb. 5 if it is to come up for a vote in by the entire House. Our hunch is that the supporters have a good chance to accomplish that. The committee chair, Rep. Joe Fitzgibbon, D-Seattle, is a co-sponsor of the bill. Another member of the committee, Rep. Joan McBride, D-Kirkland, was involved in improving lighting ordinances when she was mayor of that city.

Interested people who were unable to attend Tuesday’s hearing can testify about the bill online. This makes a difference. Write today!

More information:

• Text of HB 2057
• House staff summary of HB 2057
• Bill history page
• Our coverage of the bill’s introduction last year
• Our coverage of the tabling of the bill