Category Archives: lectures

Annual Moon viewing festival highlights week’s calendar

The last installment of the Pacific Science Center’s Science Café series and an annual Moon viewing festival are the high points of this week’s astronomy events calendar.

Viewing the Moon

Seattle Japanese GardenThe popular annual Moon Viewing Festival at the Seattle Japanese Garden will be held beginning at 6 p.m. Saturday, September 17 at the garden, which is within the Washington Park Arboretum in Seattle. The evening will include music, a haiku contest, and a traditional Japanese Tea Ceremony. Volunteers from the Seattle Astronomical Society will be on hand with telescopes to offer a great, close-up view of the Moon. Unfortunately, as of this writing the event is sold out.

Farewell to the science café

Pacific Science CenterThe Pacific Science Center is discontinuing its Science Café program after more than ten years at The Swiss Restaurant & Pub in Tacoma, Wilde Rover in Kirkland, and, up until a year or two ago, T.S. McHugh’s in Seattle. The center plans to have many of the same sorts of speakers and topics at its new, onsite Science in the City lectures.

One final astronomy-themed science café remains on the calendar and will be held at The Swiss at 6:30 p.m. Tuesday, September 13Josh Krissansen-Totton of the University of Washington Astrobiology Program and Department of Earth and Space Sciences will give a talk titled “The Search For Life Beyond Earth.” Krissansen-Totton will go beyond the headlines and explore how astronomers and astrobiologists are trying to detect life on exoplanets, and when they’re likely to be successful. Admission is free. Bring questions; there’s always plenty of time for Q-and-A.

OAS meets

Olympic Astronomical SocietyThe Olympic Astronomical Society will hold its monthly meeting at 7:30 p.m. Monday, September 12 in room Art 103 at Olympic College in Bremerton. They plan to make a comet, among other activities.

Futures file

You can scout out future astronomy events on our calendar. New additions this week include:

Up in the sky

September often offers great weather for stargazing as it’s still typically fairly warm in the evenings but the nights are getting longer. This Week’s Sky at a Glance from Sky & Telescope magazine and The Sky This Week from Astronomy have observing highlights for the week.


Wednesday astronomy at UW

Most of the week’s astronomy activity is focused on a couple of events Wednesday at the University of Washington.

Seattle Astronomical SocietyThe Seattle Astronomical Society will hold its monthly meeting at 7:30 p.m. Wednesday, June 15 in room A102 of the Physics/Astronomy building on the Seattle campus. Society member John McLaren will give a presentation about solar exploration, covering early human interactions with the Sun and their unexpected impacts on our growing technology. He’ll discuss how we learned about the Sun before the space age, what we’ve since discovered from space-based observing, and what the future holds for solar observations from space. The meeting is open to the public.

TJO goes retrograde

Theodor Jacobsen Observatory

Photo: Greg Scheiderer.

After the SAS gathering you’ll have just enough time to dash up campus to one of the twice-monthly open houses at the Theodor Jacobsen Observatory, which begins at 9 p.m. With both Mars and Saturn in the retrograde parts of their orbits, the observatory director, Dr. Ana Larson, will talk about what that means, will discuss the historical context, and help visitors plot the motion of Mars against the background stars using a star map.

With both planets well placed for viewing, hope for clear skies and at peek at them through the observatory’s vintage telescope, operated by volunteers from the Seattle Astronomical Society.


The Willard Smith Planetarium at Pacific Science Center has several astronomy shows every day. Check our calendar for the schedule.

Pacific Planetarium in Bremerton will offer public shows on Friday, June 17, with hourly presentations at 5 p.m., 6 p.m., and 7 p.m. The topic will be star hopping: how to explore the heavens using the constellations and stars as a guide. Admission to the shows is $5.

Up in the sky

Jupiter, Mars, and Saturn all remain well placed for evening viewing these days, but there’s plenty more to see. The Sky This Week from Astronomy magazine and This Week’s Sky at a Glance from Sky & Telescope have other observing highlights for the week.


Space oddities at Astronomy on Tap Seattle

Things got a little strange at the most recent gathering of Astronomy on Tap Seattle, and not just because we were all drinking beer at Hilliard’s Beer Taproom in Ballard and enjoying eats from the Cave Man Food Truck parked outside. The event, organized by astronomy graduate students at the University of Washington, took on space oddities like Hanny’s Voorwerp and Thorne-Żytkow Objects.

Seattle Astronomy gets all sentimental about Hanny’s Voorwerp because it has a cool name and it was a subject of our third post ever when we started this effort in January 2011. The Voorwerp was noticed by Hanny van Arkle, a Dutch schoolteacher who was categorizing galaxies in Sloan Digital Sky Survey images as part of the Galaxy Zoo project. The object (voorwerp is Dutch for thing or object) appeared as a blue blob near the galaxy IC 2497.

What’s a voorwerp?

John Ruan

Graduate Student John Ruan spoke about Hanny’s Voorwerp at Astronomy on Tap Seattle May 25. Photo: Greg Scheiderer.

During his talk titled, “Citizen Discovers Strange Black Hole Echoes: The Science Behind Hanny’s Voorwerp,” UW graduate student John Ruan said there were four ideas about what it was. All of them were wrong.

Imaging artifact. It could have been just a blip on the camera, Ruan said, but other observers were able to spot it.

Unknown solar system object. Ruan said solar system objects move rapidly, but the Voorwerp was found on photographic plates made more than 50 years ago, and it hadn’t budged.

Distant, high-redshift galaxy. The redshift was not high enough for the Voorwerp to be at great distance.

Milky Way nebula. Conversely, it wasn’t something in our own galaxy, either, this time because the redshift was not great enough.

It was in examining the spectra, though, that Ruan said a clue was found. The emission lines were strong.

“To get emission lines that are this strong, you need a really, really bright source that emits a lot of high-energy light,” Ruan said, the kind of light you get from gas falling onto a black hole. “This is evidence that this object was produced by a quasar.”

Hanny's Voorwerp

Hanny’s Voorwerp appears as a green blob in this photo by NASA, ESA, W. Keel (University of Alabama), and the Galaxy Zoo Team.

There was just one small problem with the idea. There’s no quasar in any of the photos. Ruan said the quasar was probably created when the galaxy merged with a smaller one.

“It disturbs the gas in this larger galaxy, and this gas, some of it, because it’s disturbed it will fall into the center of the galaxy and fall into the black hole,” Ruan explained. This ignited the quasar, but at some point it literally ran out of gas.

“That quasar became quiet again, and it looked like just a normal galaxy, however the gas cloud that the quasar was shining on still appears to be lit up,” he said. “And that is Hanny’s Voorwerp.”

Similar objects have been discovered and are generally referred to as quasar ionization echoes. Ruan said Hanny’s Voorwerp will gradually fade as the ionization of the gas wears off.

The weirdest stars in the universe

Emily Levesque is just finishing her first year on the astronomy faculty at the University of Washington, and her research bailiwick fit perfectly into space oddity night.

Emily Levesque

Emily Levesque makes a point about TZOs. Photo: Greg Scheiderer.

“I study weird stars, strange stars, the really oddball stars that we can’t easily explain,” Levesque said. Indeed, she started out looking at the odd couple of stars: red supergiants and neutron stars.

Red supergiants are enormous, massive, relatively cool stars. The largest one found so far is so big that it’s surface, if it were plunked into our solar system in place of the Sun, would reach almost out to the orbit of Saturn. Neutron stars are the small, dense remains of supernovae. They are no bigger than a city.

“There’s only one thing that I can do to red supergiants and neutron stars to make them weirder at this point,” Levesque said. “If we put a red supergiant and a neutron star into a binary, and we merge them, we get a very, very weird object.”


The weird object is called a Thorne-Żytkow Object (TŻO) because Kip Thorne of Caltech and Anna Żytkow of the University of Cambridge hypothesized just this sort of thing way back in 1977. Żytkow heard that Levesque was studying red supergiants, and sent an email asking if she’d like to give a shot at spotting a TŻO. It was quite a challenge.

“A neutron star is the size of the city of Seattle,” Levesque said. “A red supergiant is bigger than the orbit of Jupiter. If you embed a neutron star inside a red supergiant it’s virtually impossible to detect.”

As with Hanny’s Voorwerp, the spectra were the key. Inside a TŻO, convection pockets would circulate material and create bizarre chemical processes. As stuff nears the neutron star at the core it would be bombarded with protons, changing it into a different element. Then as it nears the surface of the star, it would decay into yet something else. The process repeats. If the spectrum reveals the presence of elements that you would not normally expect to see at the surface of a cold star, you may be onto something.

Two years ago Levesque and her team looked at 100 red supergiants, and 99 of them appeared normal. The spectrum of one of them, HV 2112, showed unusual concentrations of rubidium, lithium, and molybdenum.

“This was a signature that we’d actually found the first example of a Thorne-Żytkow Object in the universe,” Levesque said.

If true, it means a new way to make stars and a new way to make elements. Levesque said they’re still calling the star a candidate or possible TŻO because of the Sagan Standard that holds that extraordinary claims require extraordinary evidence.

“The evidence that we have is really compelling, but it’s three little blips in a spectrum,” Levesque said. “We desperately want to find more of these, we want to find other ways of detecting them. We’d ultimately love to have a whole set of Thorne-Żytkow Objects, and have a whole set of stars that we can look at that can hold the title of weirdest star in the universe.”


Mars at opposition, AoT looks at weird objects

Mars from Hubble

Astronomers using NASA’s Hubble Space Telescope captured this striking image of Mars on May 12, when the planet was 50 million miles from Earth. Image Credit: NASA, ESA, the Hubble Heritage Team (STScI/AURA), J. Bell (ASU), and M. Wolff (Space Science Institute).

The season of Mars begins this week as the Red Planet reaches opposition on Sunday, May 22! That means that Mars will rise around sunset, be highest in the southern sky at around 1 a.m., and will be visible all night long. When Mars is at opposition it also is near its closest approach to Earth, which this year happens on Memorial Day.

This year’s apparition is a particularly favorable one for Mars, which will draw nearer to Earth than it has been in more than a decade. At closest approach on May 30 Mars will be just 46.8 million miles away from us; it will be at its brightest for the year and we will have our best chance to see surface details through our telescopes. After Memorial Day Mars and Earth will slowly get further apart and Mars will appear to grow dimmer. The best views will be through June, but Mars will be reasonably well placed for observation through the rest of the year.

This NASA site has good information about the Mars opposition and current activity on the Red Planet.

Space oddities

AoT Seattle May 25, 2016The next edition of Astronomy on Tap Seattle is coming up at 7 p.m. Wednesday, May 25 at Hilliard’s Beer Taproom in Ballard. The monthly event organized by graduate students in astronomy at the University of Washington this time takes a look at real-life space oddities. UW astronomy professor Emily Levesque will talk about her research on “The Weirdest Stars in the Universe,” and grad student John Ruan will give a talk titled, “Citizen Discovers Strange Black Hole Echoes: The Science Behind Hanny’s Voorwerp.”

Astronomy on Tap also features trivia contests, good beer, good science, and a lot of fun. There are typically more participants than there are chairs, and the organizers suggest you can bring a lawn chair and create your own premium seating.

Fly above it all

Above and BeyondAbove and Beyond: The Ultimate Interactive Flight Exhibition opens May 28 and runs through September 10 at the Museum of Flight. It’s the west coast premiere for the exhibition, which explores the wonder of flight and the marvels of aerospace innovation, design, and technology. Above and Beyond is designed to be the most interactive touring exhibition on aerospace, with approximately 5,000 square feet of exhibition space, including a 180-degree immersive theater presentation, a high-tech media-rich historical timeline, a simulated space elevator ride, a challenge to design and test a supersonic fighter jet in a virtual high-speed flying competition, and an avatar-based motion-capture group experience that demonstrates flight like a bird.

Astronaut Tom Jones

Astronaut Tom Jones. Photo: NASA.

Seattle Astronomy plans to run a full-length preview of the exhibition later this week. It has been at the Smithsonian and in Abu Dhabi, and recently wrapped up runs at the St. Louis Science Center and the Gaillard Center in Charleston, South Carolina.

Shuttle astronaut Tom Jones will be at the museum Saturday to help kick off Above and Beyond. At 2 p.m. Jones will give a talk about what it’s like to fly in space. Afterward, he’ll sign copies of his book, Ask the Astronaut: A Galaxy of Answers to Your Questions on Spaceflight (Smithsonian Books, 2016). The lecture, and the exhibition, are free with admission to the museum.

Books by Tom Jones:

Up in the Sky

With Mars reaching opposition we have a pretty good three-planet show in the evenings. Jupiter was at opposition March 8 and these days is high in the south at dusk and sets around 2 a.m. Saturn will be at opposition June 3. This Week’s Sky at a Glance from Sky & Telescope magazine and The Sky This Week from Astronomy have additional observing highlights for the week.


New Horizons reveals much, raises questions about Pluto

I overheard a little academic snark after a recent University of Washington astronomy colloquium. “It must be nice to be a planetary scientist,” said one attendee. “The answer to everything is, ‘I don’t know.’”


Will Grundy. Photo: Lowell Observatory.

The topic of the day was Pluto, and the speaker was astronomer Will Grundy of Lowell Observatory. Grundy is a co-investigator for the New Horizons mission that flew past Pluto last July and will be beaming data back to Earth through the end of this year. He heads up the mission’s surface composition science theme team.

To be sure, Grundy’s talk was peppered with words like probably, puzzle, conjecture, speculation, and, yes, “We don’t know.” To be fair, we have learned quite a lot from a spectacular collection of snapshots beamed back to Earth from a dwarf planet three billion miles away. UW astronomy professor Don Brownlee talked about the scientific achievement, and the advances of the last 50 years, in his introduction of Grundy.

“Mariner 4 went to Mars and took 22 exciting pictures which we would now think were absolute dirt because they were 200 by 200 pixels and had very poor signal-to-noise ratio,” Brownlee said. “We’ve had this fantastic half-century of discovery of things where objects in the solar system went from dots to actual worlds. The last first-time is Pluto.”

One thing that we know fairly definitively is the variety of materials that are on Pluto’s surface. Grundy, who is a spectroscoper, showed many of the colorful images that reveal which compounds are there.

“The outer solar system would be a really colorful place if our eyes could just see a little farther out into the infrared,” Grundy noted, “but I guess it wasn’t advantageous to us running around on the African savannah to be able to distinguish methane ice from nitrogen ice.”

Psychedelic Pluto

“The outer solar system would be a really colorful place if our eyes could just see a little farther out into the infrared,” says New Horizons scientist Will Grundy. Mission scientists made this false color image of Pluto using a technique called principal component analysis to highlight the many subtle color differences between Pluto’s distinct regions. Image Credit: NASA/JHUAPL/SwRI.

Many other images showed the fascinating and varied terrain of Pluto, and this is where a lot of the we-don’t-knows come in. There are features that look for all the world like drainage canals, but it’s way too cold on Pluto for liquids. Perhaps the features were caused by glaciers, or some material we don’t know about. Other areas show what look like sand dunes with ripples on them, but Pluto’s atmosphere is too thin to blow sand around. Perhaps there was a thicker ancient atmosphere. Each photo revealed amazing detail and features, and many may well remain mysteries until more data can be collected.

“All of these different things are going on on different time scales,” Grundy said. “Sorting out the processes that we’re seeing here is going to be a fun challenge.”

The images are truly remarkable, though Grundy suggested they’re even better in higher resolution than he could display on the lecture-room screen. He suggested delving into the New Horizons image archive for some good viewing.

Pluto may seem insignificant to some, especially in light of its reclassification to dwarf planet, but Grundy said it’s well worth it to explore the “cold fringes of the solar system.”

“These things are really faint, really far away, really hard to get to, not huge,” he said. “Arguably they are the debris that’s left over from the formation of the giant planets, and they preserve a lot of clues about the planet-formation process specific to our solar system and perhaps general solar systems more broadly.”

“From my point of view, I’m just interested in exploration, just seeing what the objects out there are like.” Grundy continued. “If you like geology, or real estate, most of the solar system’s solid surface is out there.”

As New Horizons continues to beam back data it collected during last summer’s fly-by, it also is zipping toward another Kuiper Belt object, 2014 MU69, at which it will arrive on New Year’s Day 2019.

There’s another chance to catch Grundy’s presentation about Pluto coming up this weekend. He is scheduled to give a talk titled “Pluto and Charon Up-close” at 2:15 p.m. Sunday, May 22 at the PACCAR IMAX Theater at the Pacific Science Center. It’s part of the center’s on-going observance of AstronoMay.


The universe is big, even in small spaces

The universe is pretty vast even in confined spaces. That was the lesson given on opposite ends of the size scale at the most recent Astronomy on Tap Seattle event hosted at Hilliard’s Beer Taproom by University of Washington graduate students in astronomy.

Ethan Kruse

UW astronomy graduate student Ethan Kruse said the universe is a big place, and it will take some technological advances to reach Alpha Centauri in 20 years. Photo: Greg Scheiderer.

Grad student Ethan Kruse was all set to give a talk that concluded we would never even get out of our solar system because it is way too big. Then a few weeks before the talk Stephen Hawking and friends announced their plan for getting all the way to neighboring star Alpha Centauri in 20 years through a project called Breakthrough Starshot.

“If I’m disagreeing with Stephen Hawking,” Kruse recalled thinking, “I should probably stop for a minute and reevaluate my thesis.”

Kruse remained on point about the mind-boggling scale of the universe. He said that if our Sun was the size of a basketball sitting on the stage of Hilliard’s, Earth would be the size of a sesame seed in the back of the room, 84 feet away, and the orbiting Moon would be the size of a grain of salt. At this scale Jupiter would be a golf ball on the Ballard Bridge and Pluto would be a grain of salt about a kilometer away—about the distance to Bad Jimmy’s Brewing Company, which served as the venue for Astronomy on Tap Seattle for its first year. Alpha Centauri, in this set-up, is some 4,400 miles away—in London or Tokyo.

Kruse pointed out that the fastest spacecraft we have built so far, New Horizons, took a decade to get to Pluto.

“We went from Hilliard’s to Bad Jimmy’s in ten years,” he observed. “Don’t worry guys, we’re going to go to London in 20 years!”

The idea behind Starshot is that a super-light craft with a light sail could be accelerated by lasers to up to 20 percent of the speed of light. Kruse outlined a litany of technological challenges with the concept, including the ability to generate sufficient laser power, creating an adequately reflective material for the sails, being able to accurately aim the lasers at great distances, and shielding the craft from possible collisions with space debris. Still, he concluded, the idea is worth exploring, especially since the same technology could be used to explore the solar system more quickly.

“This is honestly the most realistic thing that anyone has proposed so far for getting to any other star system,” Kruse said.

It will, however, take a great deal of research and development.

“Don’t necessarily count on this before you die,” Kruse concluded. “Space is big.”

Jessica Werk

UW astronomy Prof. Jessica Werk says your atoms took quite a journey to become you. Photo: Greg Scheiderer.

Professor Jessica Werk, one of the newest hires onto the astronomy faculty at the University of Washington, also used sports equipment to illustrate her talk, “The History of You: The Rather Tumultuous Past of the Atoms in Your Body.” Werk pointed out that atoms are mostly empty space. If the nucleus of an atom were the size of a baseball, the nearest electrons would be a football field away.

After the Big Bang the universe was mostly light atoms: hydrogen and helium and a few others. Where did the carbon and calcium and other heavier stuff we’re made of come from?

“All evidence suggests that these atoms were fused in the cores of very, very massive stars twelve-and-a-half billion years ago,” Werk said. “Since then they have been on an absolutely crazy, long, sometimes violent journey to end up in your body 93 million miles from the Sun on this speck named Earth.”

Those atoms took a somewhat circuitous route to get here.

“Sixty percent of the atoms in your body we at one point outside of the galaxy in the circumgalactic or intergalactic medium,” Werk said. We don’t really know how they got here, but the best theory is that the atoms tend to cool off, and the gas rains back down on the galaxy, collapsing in star formation or becoming part of the debris disk out of which planets form.

There’s some mind-bending scale at the atomic level, too. Werk pointed out that there are 1023 atoms in a breath of air.

“Each breath-full of air contains more atoms than the number of breath-fulls of air in the entire Earth’s atmosphere,” she said. “What that means is that it is very likely that the last breath of air you just took contained at least one oxygen atom from the first breath of air that you ever took as a human being on planet Earth.”

That reminds us of a recent post by Ethan Siegel on the blog Starts With a Bang, in which he concluded that we all probably share atoms that were once part of King Tut or any other historical figure you might name.

AOT crowd

Astronomy on Tap Seattle outgrew Bad Jimmy’s, and pretty well packed the larger Hilliard’s at its first event there in April. Photo: Greg Scheiderer.

“The matter that makes up your physical body is part of a huge universe that is continually evolving and recycling the material in it into new forms,” Werk concluded.

The next Astronomy on Tap Seattle event is set for 7 p.m. Wednesday, May 25 at Hilliard’s. Astronomy Prof. Emily Levesque and graduate student John Ruan will give talks about some of the strangest celestial objects ever discovered or theorized. People outnumbered seats at the April event, and so the organizers suggest that you can bring a lawn chair and create your own premium seating.


AstronoMay continues at PacSci with two talks this week

Saturday was Astronomy Day, but the Pacific Science Center is taking the whole month to celebrate AstronoMay! Two interesting talks highlight the calendar for the week.

Brett Morris

Brett Morris

Brett Morris, one of the co-founders of Astronomy on Tap Seattle, will give a presentation titled, “Hunting For Life in the Universe” at a Teen Science Café at 7 p.m. Wednesday, May 18 at the center’s PACCAR IMAX Theater. Morris will introduce the science of astrobiology and how it seeks to measure and locate the conditions necessary for life in the universe. He’ll talk about telescopes and techniques used to explore other worlds and to try to track down life on them.

Dr. Will Grundy, the lead investigator for the surface composition team of New Horizons, will give a talk titled, “Pluto and Charon Up-close” at 2:15 p.m. Sunday, May 22 at the PACCAR Theater. Grundy will show close-up images from the mission and discuss his research, which involves icy outer solar system planets, satellites, and Kuiper belt objects using a broad variety of observational, theoretical, laboratory, and space-based techniques.

Volunteers from the Seattle Astronomical Society will be on hand at the center Saturday and Sunday with solar telescopes for viewing of the Sun. AstronoMay also includes planetarium shows, screenings of the movie A Beautiful Planet 3D, and other activities. Check the AstronoMay calendar page for a full listing.

Club events

saslogoThe Seattle Astronomical Society will hold its monthly meeting at 7:30 p.m. Wednesday, May 18 in room A102 of the Physics/Astronomy building on the campus of the University of Washington in Seattle. Solar System Ambassador Ron Hobbs will give a talk titled, “Juno to Jupiter: Piercing the Veil.” The Juno spacecraft will arrive at Jupiter in July. Over the ensuing year and a half, it will peer through the Jovian cloud tops and provide a deeper understanding of the composition and structure of the Solar System’s largest planet. Hobbs will explain what exciting science to expect from NASA’s latest outer planet mission.

Rose City AstronomersRose City Astronomers will hold their monthly meeting at 7:30 p.m. Monday, May 16 at the OMSI auditorium in Portland. It will be the group’s annual astronomy fair, with a swap meet, info booths, and brief show-and-tell sessions.

TJO open house

Theodor Jacobsen ObservatoryThere will be an open house at the University of Washington’s Theodor Jacobsen Observatory at 9 p.m. Wednesday, May 18. Students Cale Lewandowski and Jason Busnardo will be giving a talk about how to overcome the challenges of a trip to Mars. Reservations are strongly recommended for the talks, which are held in a small classroom in the observatory and often fill up early. Volunteers from the Seattle Astronomical Society will offer tours of the observatory and a look through its vintage telescope if weather permits.

Up in the sky

Mars is nearing opposition and Jupiter remains well placed for observing. This Week’s Sky at a Glance from Sky & Telescope magazine and The Sky This Week from Astronomy have other observing highlights for the week.