Tag Archives: Brett Morris

CSI Universe: Unraveling the mysteries of Tabby’s Star and supernovae

The universe is full of mysteries; that’s one of the reasons that astronomy is so interesting! We dug into a couple of puzzling phenomena at the most recent gathering of Astronomy on Tap Seattle at Peddler Brewing Company in Ballard. The session was dubbed “CSI: Universe,” and Brett Morris, one of the co-hosts of Astronomy on Tap Seattle and a Ph.D. candidate at the University of Washington, gave a talk about the star KIC 8462852, more commonly called Tabetha Boyajian’s star, thank goodness. His talk was titled, “The Weirdest Star Gets Weirder.”

You helped

Citizen scientists were the first to notice that there was something odd about Tabby’s Star. The Kepler Space Telescope was searching for exoplanets by watching for slight but regular dips in a stars brightness, a possible indication of a planet in orbit around a distant star. Morris noted that it can be difficult to write a computer algorithm to filter out noise in the data, so they enlisted the help of the public through the website PlanetHunters.org.

Brett Morris

Brett Morris (Photo: Greg Scheiderer)

“What you can do on this website is help scientists look for things that are weird,” Morris said. People identify objects that don’t look right, then professional astronomers check them out. “Through this process they found a whole bunch of stars that misbehave.”

One of them was Boyajian’s.

“If we look at its colors, if we look at its spectrum, it behaves like all the other F-stars,” Morris said, “and so we were a little bit puzzled when we started looking at data.”

There were dips in light from Tabby’s Star, all right. There were smaller dips early in the mission that never really matched up. Then in March 2011 there was a huge dip of 15 percent of the star’s light, and it lasted for days, not hours as most transits do. Then in February 2013 there was an even bigger reduction in brightness of 20 percent. Nobody has come up with a plausible explanation for this.

“Whatever this is, this thing’s big,” Morris said.

No easy answer

An astounding array of possible explanations have been thrown out there. Examples include an object like Saturn with rings that could cause variations in the light curve, a passing comet, debris from a huge planetary impact like the one thought to have formed our Moon, and Tabby’s Star’s indigestion from having just swallowed a whole planet. The one in vogue at present is that a family of 10 to 20 comets, all giving off material, are creating these odd light curves. Morris doesn’t quite buy this one, either.

“The more bodies that you imagine being there, the easier it is to fit a light curve,” he said. “If you just keep adding new parameters into your model, eventually it will fit.”

“If you invoke wierdly shaped objects, you can fit it perfectly,” Morris added. “If you invoke the kinds of objects that we expect are most likely, it’s a lot harder. We really don’t know what this star is doing.”

Some have wondered if something between us and Tabby’s Star, maybe interstellar gas or dust, caused the strange light curves. Morris himself investigated this one. Back in May he got a Tweet—he said this is mostly how astronomers communicate these days!—noting that Tabby’s Star’s brightness was changing. He used the Apache Point Observatory to look for signs of absorption from interstellar gas or dust. But the spectra didn’t change even though the star was changing.

“We’re slowly ruling things out,” Morris said. “It’s not something in our solar system, it’s not something between us and the star; it’s got to be something near the star, but we don’t know what near the star could be doing this.”

As for wild speculation that the strange light curves could be caused by a Dyson Sphere or other “alien megastructure”:

“Extraordinary claims require extraordinary evidence, and I do not have any evidence to suggest that we can make a claim as extraordinary as that,” Morris said. He and a team of undergraduates at the University of Washington continue to work on the puzzle.

Coroner for the Stars

The second talk of CSI: Universe came from Prof. Melissa Graham of the UW, who does work on supernovae. These mark the death of a star, and Graham’s job is to figure out whodunnit.

Melissa Graham

Melissa Graham (Photo: Greg Scheiderer)

Graham pointed out that a star is considered alive if it’s in hydrostatic equilibrium; that is, when atomic fusion in the star’s core supports the star by counteracting gravity. Sometimes the death of a star is from natural causes. A typical star will fuse hydrogen and helium into carbon, then gradually fuses neon, oxygen, and heavier elements until eventually a core of iron forms. Graham said this means trouble, because fusing iron into something heavier is not exothermic; it doesn’t release energy.

“If you end up with a core of iron, your hydrostatic equilibrium suffers because you are losing out on that fusion in the core,” she said. “The core collapses because it can’t support itself anymore, the outer layers fall onto the inner layers, and you end up with a supernova explosion.”

Material blows away and leaves neutron star behind.

“That’s death by natural causes,” Graham said.

Type 1a supernovae are more interesting to stellar criminologists. These involve a white dwarf star, which is the remnant of a smaller star that doesn’t have enough mass to fuse carbon and oxygen into anything heavier.

“The carbon and oxygen core shrinks under its own self-gravity, and the outer layers are lost, which causes a really pretty planetary nebula,” Graham said. “The star is now supported by electron degeneracy pressure.”

This means the star isn’t alive because it’s not fusing elements.

“It’s more of a zombie star,” Graham said. “It’s died once and continues to live.”

The usual suspects

It’s a suspicious death when you see one of these explode. Graham rounded up the usual suspects: It could be a binary companion, such as a red giant or a sun-like star or another white dwarf. Sometimes it could be a pair of white dwarfs with a third companion star. A type 1a supernova also might from from a white dwarf’s impact with a primordial black hole or comet.

One way to figure this out is to simply look at the scene of the crime.

“Once this white dwarf star explodes, the other companion star would still be there,” Graham said. A companion would heat up and get brighter, so it might be detectable. Interstellar dust and gas may also light up from the energy of a supernova. Looking back at the scene later might detect such material that is at significant distance from the event. Graham is using the Hubble Space Telescope to check to find out if this is happening. She’s also looking forward to the completion of the Large Synoptic Survey Telescope, which is expected to find some ten million supernovae over its 10-year mission. With so many new examples we will, “really start to understand how these carbon-oxygen white dwarfs die,” Graham said.

More information:

Morris’s talk on YouTube

Ted Talk by Tabetha Boyajian

 

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Good events and maybe actual observing as holiday weekend approaches

We hope you have had a chance to dust off the telescope and get in some observing with the recent good weather. Seattle Astronomy had some fine looks at Jupiter and Saturn over the weekend. The forecast looks promising for some public star parties next weekend, too.

The Seattle Astronomical Society plans its free monthly public star parties for 9 p.m. Saturday, July 1 at two locations: Green Lake in Seattle and Paramount Park in Shoreline. Bad weather cancels these events, so watch the website for updates.

SAS is also involved, along with the Boeing and Tacoma clubs, with the Covington Community Park star party set for 9 p.m. Friday, June 30. This one, too, is weather dependent.

The Tacoma Astronomical Society will hold one of its public nights at 9 p.m. Saturday, July 1 at the Fort Steilacoom campus of Pierce College. The indoor program will be about constellations and star-hopping. The telescopes will come out under clear skies.

The Eastside Astronomical Society will hold its monthly meeting at 7 p.m. Tuesday, June 27 at the Newport Way Library in Bellevue. The topic for the night will be the August total solar eclipse. EAS doesn’t meet during the summer, so this will be its last gathering until September.

AOT SeattleAstronomy on Tap Seattle will hold another of its gatherings at Peddler Brewing Company in Ballard at 8 p.m. Wednesday, June 28. The topic for the evening will be CSI: Universe. AOT Seattle co-host Brett Morris will give a presentation titled “The Weirdest Star in the Universe Gets Weirder,” an update on Tabetha Boyajian’s star in light of its recent misbehavior. UW observational astrophysicist Dr. Melissa Graham will speak about her research as “Coroner For The Stars,” working to unravel the mysteries of supernovae.

There’s plenty of time for Q&A and prizes to win in astro-trivia.

It’s free, but buy beer, and bring a chair to create your own front-row seating.

Asteroid Awareness Day is Friday, June 28, and the Museum of Flight will offer educational activities and livestream lectures between 10 a.m. and 2 p.m. in its Alaska Airlines Aerospace Education Center.

Also Sprach Zarathustra

The Seattle Symphony is going to show the science fiction classic 2001: A Space Odyssey this weekend, and they’ll be providing some of the music live! Performances are at 8 p.m. this Friday and Saturday, June 30 and July 1. Tickets, available online, range from $38 to $128.


 

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AoT Seattle celebrates 1st birthday, announces move to larger venue

Astronomy on Tap Seattle last month celebrated its first year of of bringing the latest astronomical research and good beer to interested space geeks. The party was a little bittersweet, as they also announced that the series will be leaving Bad Jimmy’s Brewing Company for the larger Hilliard’s Beer Taproom, another Ballard watering hole.

AOT at Bad Jimmy's

Astronomy on Tap Seattle packed in the crowds in its first year at Bad Jimmy’s. The series is moving to the larger Hilliard’s Taproom in Ballard. Photo: Greg Scheiderer.

The move does not come entirely as a surprise. The early Astronomy on Tap events last spring were well attended, and they’ve grown in popularity to the point where nearly 140 people were sardined into Bad Jimmy’s for the monthly gatherings. Brett Morris, an astronomy graduate student at the University of Washington who is the emcee and one of the co-founders of Astronomy on Tap Seattle, hinted at a move in an interview we posted before the birthday event.

“It’s been a wild ride growing from our initially small size to something that we almost can’t handle,” said Morris. “We’re going to try our best to keep up with it as it grows through our second year.”

Kristin Garofali, another co-founder of AoT Seattle, thanked Bad Jimmy’s for their support over the first year, noting that they even let participants vote to name their imperial Scotch ale (The Big Sipper) and at the birthday party served up a delicious version of it that was aged for several months in rum barrels.

“To see how this has grown has been super amazing,” Garofali said. She added that they hope to keep doing smaller events at Bad Jimmy’s.

We recently attended one of the Pacific Science Center’s PubSci events at Hilliard’s, which probably has four times the floor space of Bad Jimmy’s.

Supernova impostor

Breanna Binder gave an interesting talk at the March 23 birthday event, about a supernova impostor that turned out to be an x-ray binary system. An amateur astronomer spotted what looked like a supernova in 2010, but it kept churning out x-rays long after it faded visually. Binder said that’s not how it’s supposed to work.

“Supernova 2010da, not only is it not a true supernova, it may be the youngest possible x-ray binary,” Binder said, noting that it theoretically takes between four and five million years before an x-ray binary begins emissions. They’d seen none prior to 2010. “The 2010 eruption might have been the birth of a brand new x-ray binary, which is something that we had never witnessed before.”

The story was featured on the popular website IFLScience. Binder will give a talk about the supernova impostor at the UW Astronomy Colloquium at 4 p.m. Thursday, May 5 in room A102 of the Physics/Astronomy Building on the UW campus in Seattle.

Planet 9

One of the other more interesting mini-talks of the evening was made by Dave Fleming, who took a look at the possible Planet 9. Astronomers have recently speculated that there’s a ninth planet in our solar system, a so-called super-earth that is somewhere between Earth and Neptune in mass and about 700 astronomical units out. Fleming noted that a fair chunk of the exoplanets discovered so far are in that mass range.

“If there is one of these guys lurking in the solar system, if we could actually detect it with a telescope and send a probe to it, it would give us a huge insight into the planet-formation process,” Fleming said. “If this ninth planet does exist, maybe it’s some relic of the planet-formation process that got scattered out by Jupiter.”

Former planet 9, and more

Morris showed a large number of photos that New Horizons shot at Pluto. He had given a talk back in July, on the day of the mission’s fly-by, and shared the very first pictures it beamed back to Earth. Though it will continue transmitting data for quite some time, we already have a sizable collection of pics from the system. Among the most interesting discoveries from the new batch: a large canyon around the equator of Pluto’s moon Charon that may indicate an underground ocean.

Other talks at the birthday event covered supermassive black holes, fast gamma-ray bursts, how to find a Tatooine, and funky, planet-shaped megastructures.

The next Astronomy on Tap Seattle event is planned for April 27 at Hilliard’s. The program has not yet been published.

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Happy birthday to Astronomy on Tap Seattle

Astronomy on Tap Seattle has spent the last year confirming that astronomy and beer together make a great combination. We will celebrate AoT’s first year in operation with a gala event at 7 p.m. Wednesday, March 23 at Bad Jimmy’s Brewing Company in Ballard. The free astronomy talks have drawn good crowds from the beginning, and the most recent events have seen attendees packed shoulder-to-shoulder into Bad Jimmy’s.

AOT Seattle March 23“It’s been a wild ride growing from our initially small size to something that we almost can’t handle,” said Brett Morris, an astronomy graduate student at the University of Washington who is the emcee and one of the co-founders of Astronomy on Tap Seattle. “We’re going to try our best to keep up with it as it grows through our second year.”

Morris said they had a hunch before they started that the audience was out there. Astronomy on Tap started in New York and has spread to a total of eight cities, and events elsewhere have drawn big crowds. Austin, Texas, for example, regularly attracts 400 people to its events in an outdoor beer garden.

“We knew that there was a big drive for this kind of event, especially in nerdy cities like Seattle, so we knew that the availability of participants was good,” Morris said, “but we didn’t really know if we’d be able to scale up the way we wanted or to reach the number of people that we needed to.”

They set out in hopes of being able to attract 50 people who would attend regularly to hear astronomy talks and enjoy a brew. They’ve accomplished that without any sort of paid advertising.

Brett Morris

UW grad student Brett Morris talked about the history of Pluto and the first photos from New Horizons at Astronomy on Tap Seattle July 15. He’ll give a Pluto update at the March 23 event. Photo: Greg Scheiderer.

“It seems that word of mouth among nerds is really effective. The social networks have been all that we needed to get the word out,” Morris said. “The enthusiasm that we’ve had from the audience has been unbelieveable and unrelenting, and the beer is quite delicious.”

There will be a special treat at the March 23 event. Astronomy on Tap Seattle participants named one of Bad Jimmy’s beers, a Scotch ale that popular vote dubbed “The Big Sipper.” Several months ago the brewers stowed some of that ale in old rum casks.

“We’re going to tap those barrels for the one-year anniversary and serve this barrel-aged imperial Scotch ale in special commemorative glasses, that you can also purchase, that have astronomy on Tap logos on them,” Morris said.

There will be a series of short talks at the anniversary with updates on astronomy discoveries made in the last year, including the latest photos from Pluto and the possibility of the existence of Planet 9. Morris said that one of the great things about being an astronomer is that when an idea such as Planet 9 comes out, there probably is an expert close by who can lead the discussion about how plausible it is. Astronomy on Tap is essentially an effort to take that discussion public.

“As an astronomer you get to meet a lot of people, daily, who think that astronomy is great and would love to talk to you about space, and would love to talk to you about life in the universe,” Morris said, “but it’s rare that you really encounter people who spend their free time trying to learn more about astronomy and physics, and that really is the core audience of Astronomy on Tap.”

“I am consistently surprised by how many people are passionately interested in learning astronomy and physics at a level deeper than you might find in an astronomy magazine,” he added.

It has been a boon for people who write about astronomy for fun. It’s great to have a monthly topic, and the discussions and trivia contests that are a part of Astronomy on Tap are fun and informative.

The March 23 event begins at 7 p.m. at Bad Jimmy’s in Ballard. You might want to arrive earlier than that to get a good seat! It’s free, but bring beer money.

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Astronomy on Tap takes a look at the first Pluto pics from New Horizons

Back in the olden days of 1979 I took an undergraduate course in astronomy at the University of Washington. The Voyager spacecraft had just visited Jupiter and the astronomy faculty were positively giddy about the new photos, data, and knowledge coming in from the largest planet in our solar system. The excitement is perhaps even greater as we digest the first images from New Horizons, which buzzed Pluto earlier this week and got our first really close look at what used to be the ninth planet.

“It’s discovering a new planet that we already knew existed,” said Brett Morris, a UW graduate student in astronomy, at a special Pluto-palooza version of Astronomy on Tap Seattle Wednesday evening at Bad Jimmy’s Brewing Company in Ballard.

The icy mountains of Pluto. Photo: NASA-JHUAPL-SwRI.

The icy mountains of Pluto. Photo: NASA-JHUAPL-SwRI.

Morris said the biggest discovery in the first batch of close-ups of Pluto is that, in a section of the dwarf planet’s “heart,” now named “Tombaugh Regio” after its discoverer, Clyde Tombaugh, there are no craters.

“This suggests that the surface is less than 100 million years old,” Morris said. While that may seem like a long time, it’s a mere blink of an eye astronomically and geologically.

“This is really young, and that was a huge surprise,” Morris said. “This is the biggest surprise of the day. The surface must be active.” He added that we have no idea yet how this could be happening, and that scientists didn’t expect to find such a thing.

Another interesting finding were tall mountains in that photo.

Brett Morris

UW grad student Brett Morris talked about the history of Pluto and the first photos from New Horizons at Astronomy on Tap Seattle July 15. Photo: Greg Scheiderer.

“We believe that these mountains are water-ice mountains eleven thousand feet tall,” Morris said, explaining that ice of methane or carbon monoxide would crumble at that height, but that water ice, in a place as cold as Pluto, would be as hard as rock.

“Imagine an ice cube the size of Mt. Rainier,” Morris said. “That’s what we’re looking at.”

Pluto’s largest moon, Charon, has material at its north pole that is darker than the rest of its surface which, like Pluto’s, also appears to be active. They’ve also spotted a large canyon on Charon.

“That canyon is twice as deep as the Grand Canyon, it stretches across a significant chunk of Charon,” Morris explained. “It’s either a really big crater or a valley carved out by something.”

The small moon Hydra appears to be made entirely of ice.

“This is a 30-mile hunk of ice sitting out there orbiting Pluto,” Morris said.

This animation combines various observations of Pluto over the course of several decades. The first frame is a digital zoom-in on Pluto as it appeared upon its discovery by Clyde Tombaugh in 1930 (image courtesy Lowell Observatory Archives). The other images show various views of Pluto as seen by NASA's Hubble Space Telescope beginning in the 1990s and NASA's New Horizons spacecraft in 2015. The final sequence zooms in to a close-up frame of Pluto released on July 15, 2015.

Click to view this animation, which combines various observations of Pluto over the course of several decades. The first frame is a digital zoom-in on Pluto as it appeared upon its discovery by Clyde Tombaugh in 1930 (image courtesy Lowell Observatory Archives). The other images show various views of Pluto as seen by NASA’s Hubble Space Telescope beginning in the 1990s and NASA’s New Horizons spacecraft in 2015. The final sequence zooms in to a close-up frame of Pluto released on July 15, 2015.

The photos returned by New Horizons are far better than any images of Pluto captured by the Hubble Space Telescope.

“The Hubble Space Telescope tried really hard to give us good images of Pluto, but that’s really difficult because it’s so far away,” Morris said. The telescope was able to see bright and dark regions on Pluto, but that was about it. Hubble also was used to search the Pluto system for rings, moons, and other objects that could be a hazard to the speeding spacecraft.

“At 15 kilometers a second, if there’s a piece of rice in your way it will destroy your spacecraft,” Morris noted. Four of Pluto’s five known moons were discovered by Hubble during this process.

Morris noted that it’s going to take a while for New Horizons to send us all the data it has collected during its flyby of Pluto. The spacecraft is equipped with what he says is essentially a 200-megabyte modem that only contacts Earth every once in a while.

“This is worse than AOL!” he quipped. We should keep receiving photos and data from New Horizons through November of 2016, so we have a lot of cool new discoveries to look forward to. May we be fortunate enough to enjoy a cold brew with each one of them!

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Gamma ray bursts, galaxies, exoplanets, and beer

Back in 1979 when I was an undergraduate at the University of Washington I took an introductory course in astronomy to fulfill some science credit requirements. The two Voyager spacecraft had just visited Jupiter and the faculty in the astronomy department seemed practically giddy about all of the new data received and textbook re-writing to come. These days, given the number of exciting missions returning information from the near and far reaches of the solar system, it seems we’re learning something new about the cosmos almost every day.

Case in point: earlier this week a trio of UW astronomy graduate students put on the first Astronomy on Tap event in Seattle, each giving a mini-lecture about their current research. Two of them had news fresh out of the headlines.

Zapped by gamma rays

Kristen Garofali was first up with a talk titled “To GRB or Not to GRB.” The GRB in this case stands for gamma ray burst.

Astronomy on Tap

There was a full house Wednesday at Bad Jimmy’s in Ballard for the first Seattle Astronomy on Tap event. Photo by @AoTSeattle.

“Gamma ray bursts are cosmic lighthouses,” directional beams that Garofali explained result from the formation of a black hole. “When the black hole forms there are two jets of energy emitted that are really high-energy.”

Last week, for the second time in less than a year, scientists thought they had detected a GRB from our closest galactic neighbor, M31, the Andromeda galaxy. This would have been a first; we’ve never detected a GRB so nearby before. The nearest have been billions of light years distant, while M31 is a mere 2.5 million light years away from Earth.

Both the event last May and the one last week turned out not to be GRBs. Garofali noted that there are other objects out there that emit gamma rays, but these don’t look at all like whatever was detected coming from the neighborhood of M31 last week.

“It’s too bright to be a transient or an ultraluminous x-ray source,” she said. “It’s too faint, however, to be a gamma ray burst.” Even so, Garofali finds the discovery and the mystery exciting. “It could open our eyes to some new process that we haven’t thought about before,” she said.

Garofali said the reason we should care about this is that gamma rays are nasty things. At the very least, one would foul up your cell phone reception, and a strong burst could cause mass extinction on Earth. In fact, there is some scientific speculation that a GRB may well be responsible for at least one of the mass extinctions that have hit our planet. However, to do that the GRB would have to come from relatively close by and be aimed right at us. The odds of that happening are extremely long, but not zero.

Astronomy porn

Talk number two by Nell Byler was titled “Andromeda, So Fly, So PHAT.” She wasn’t using dated slang, but rather was talking about the Panchromatic Hubble Andromeda Treasury, a key tool for her work studying stellar populations. PHAT has taken up a lot of the Hubble Space Telescope’s time; the treasury was created from some 7,400 Hubble images involving 936 exposure hours. The collected data has resolved more than 117 million stars in our neighboring galaxy. The UW’s Julianne Dalcanton is the principal investigator for PHAT.

PHAT M31

This PHAT portrait of M31 is a mosaic of more than 7,000 Hubble Space Telescope images. Photo: NASA; ESA; J. DALCANTON, B.F. WILLIAMS, AND L.C. JOHNSON/UNIV. OF WASHINGTON; THE PHAT TEAM; R. GENDLER.

Byler showed a great deal of “astronomy porn”—stunning Hubble images from the project. They’re more than just pretty pictures; Byler said PHAT has the potential to reveal much about star formation, stellar evolution, and a host of other questions about how galaxies work.

“Even though we’re looking at stars within another galaxy it provides a lot of insight for galaxies that we can’t resolve and for our own galaxy, which we think is pretty similar to Andromeda itself,” Byler said. “And there’s lots more science to be done.”

Little green men

Brett Morris closed the evening with a talk titled “Dear Grandpa.” Morris is an astrobiologist, which his grandfather thinks is a pretty fishy undertaking involving the cover-up of the existence of extraterrestrials. Morris is hoping to find ETs, though, and on the very day of Astronomy on Tap the news wires were abuzz with new information about subsurface oceans on Jupiter’s moon Ganymede and on Saturn’s moon Enceladus, both of which could be havens for life. Kenneth Chang’s article in the New York Times provides excellent coverage.

Enceladus geysers

Water vapor geysers erupt from the south pole area of Saturn’s moon Enceladus. Photo: NASA/JPL.

“Enceladus has what we call cryovolcanoes; they’re volcanos that shoot out water,” Morris said.

“I personally think that this is the best chance to look for life elsewhere in our solar system because we can send a spacecraft that just orbits this moon and picks up the water as it shoots out of the moon,” he said. “Could it get more convenient? We don’t need to dig at all!”

Morris explained how the Kepler Space Telescope hunted for planets around other stars, though he bristled a little at the fact that when one is discovered similar in size to our home world it is invariably called “Earthlike.”

“Those have very broad, flimsy definitions,” he said, noting that Venus, which is practically our twin in size and mass, could be called Earthlike, but it would not be a nice place to visit. Morris is excited for scientific advances that will help us get a better idea of what exoplanets are truly like, and to identify which ones might harbor life like us.

The Astronomy on Tap event was well attended, with more than 60 people jamming into Bad Jimmy’s Brewing Company in Ballard (which pours a lovely IPA, by the way). The talks were well received and games were enjoyed, even though our team, nicknamed “Hubble Trouble,” did not win any cupcakes donated by Trophy Cupcakes. The organizers plan to be back with more events. Follow them on Twitter at @AOTSeattle. Also watch Facebook, where they hope to set up a page soon.

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