Category Archives: lectures

Finding exoplanets by detecting magnetospheres

Scientists are developing new and more refined ways to find and characterize exoplanets, and it involves a familiar local phenomenon. Magnetospheres of distant planets may help us spot them, and could tell us a lot about their potential for habitability.

Matt Tilley, a University of Washington graduate student working on a doctoral degree in computational space plasma physics and astrobiology, gave a talk last week titled, “The Magnetospheres of Solar System Planets and Beyond.” The lecture was part of the Pacific Science Center’s PubSci series at the Hilliard’s Beer Taproom in Ballard.

Matt Tilley

Matt Tilley discussed magnetospheres and how they might help us detect habitable exoplanets. The event was March 2 at Hilliard’s Beer Taproom in Ballard, part of the Pacific Science Center’s PubSci series. Photo: Greg Scheiderer.

Tilley explained that any planet that has a strong magnetic field will have a magnetosphere generated by the stellar wind from the star it orbits. Earth qualifies.

“The solar wind is actually an electrically charged gas that carries with it a magnetic field,” he said. “It’s an electrically charged magnetic wind blowing off of the Sun at a million miles an hour.”

The magnetosphere is essentially a bubble where the stellar wind is deflected around the planet.

“It literally is the force field for Earth, and it shields the Earth from being blasted by this electrically charged magnetic wind.”

Some recent research suggests that we may be able to spot the magnetospheres of exoplanets. To date we have found some 1,800 confirmed exoplanets, most of them by the Kepler mission which watched for slight dimming of stars which would occur as a distant planet transits the stellar disk. Usually the change in the light curve is pretty uniform, but in some cases it is not. Tilley noted that material from the stellar wind can accumulate in a bow shock at the magnetosphere, and this could be enough to show up in the Kepler data.

“If you have varying amounts of density of this electrically charged magnetic gas, this stellar wind, piled up against the bow shock, it will enter and start blocking some of the light before the planet ever enters the frame of the shot,” Tilley said.

There’s still debate about whether this is actuallly what is happening, but Tilley said it would be quite a useful discovery.

“It would be our first observation of a remote magnetic field,” he noted. “That tells us something about the composition, it tells us somethigng about the mass, the rotation rate—we can infer multiple planetary characteristics from just the magnetic field, just from this distance, this one measurement of light.”

That data, plus the existence of the magnetic field, could tell us a lot about a planet’s potential habitability.

There’s another possible way to discover exoplanets because of magnetospheres. Tilley noted that the transit method only works for edge-on systems in which the transit of planets can be detected from our vantage point. It’s extremely difficult to spot exoplanets visually because they’re so dim in contrast to their host stars. However, Tilley said that the magnetosphere generates strong signals called auroral radio emissions that shoot out from the planet’s poles. Planets generate much stronger radio waves than do stars, and so for face-on systems looking for these radio waves may well be a way to detect exoplanets.

Tilley said it’s an exciting time to be working in the field.

“Astrobiology is really the study of the conditions on a planet, the stellar conditions and the planetary conditions that make the situation right for life to form and right for it to survive long enough to evolve into something interesting,” he said.

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Astronomy reduced to pixel archive science

A University of Oregon professor of physics frets that astronomy is drowning in data that threatens to reduce it to a “pixel archive science.” His solution is something right out of Star Trek.

Dr. Gregory Bothun made a presentation titled, “Big Data, Discovery, and a New Kind of Astronomy: Are We Prepared?” at the February meeting of the Rose City Astronomers at the Oregon Museum of Science and Industry in Portland. Bothun noted that efforts such as the Sloan Digital Sky Survey provide the stuff of discovery.

Gregory Bothun

Prof. Gregory Bothun of the University of Oregon spoke about astronomy’s challenges with big data to a meeting Feb. 15 of the Rose City Astronomers in Portland. Photo: Greg Scheiderer.

“The great thing about surveys is that they produce a catalog of calibrated sources which serve the community on a worldwide basis and involve more people in astronomy,” he said, adding that, for this reason, surveys should come before more targeted observations of individual objects.

“We’ve done it the other way around, mostly because of some kind of fetish with large-aperture glass,” Bothun said. “We have spent far more money building large telescopes than we have on building real, useful surveys that serve the community.”

Bothun pointed out that sometimes a big telescope will do a survey, such as Hubble’s ultra-deep-field work, and this leads to tremendous advances.

“Every time an instrument does a calibrated survey, science moves forward much more rapidly than some individual working with some piece of aperture doing a follow-up observation,” Bothun said.

A pipeline problem

While Sloan was useful, Bothun said, it also illuminated a problem. It took eight years to get the survey’s 20 terabytes of data into the hands of scientists.

“We’re not good at pipeline processing of survey data in a timely manner to feed a community,” Bothun said. “We shouldn’t have to wait eight years to go from acquired pixels to reduced data to analysis. It should just happen instantly. To the extent that it doesn’t is the extent that we’re going to shoot ourselves in the foot and turn astronomy into a science that archives pixels.”

3point2billionpixelsThe problem is about to get more challenging. A coalition of institutions is building the Large Synoptic Survey Telescope (LSST) in Chile. The LSST camera will have 3.2 billion pixels, and at 16 bits per pixel, each image it captures will be a whopping 6.4 gigabytes.

“Try to take a selfie of that and send it to your mom over wifi,” Bothun quipped. The challenge, though, is no laughing matter. It’s difficult to move that much data around, and it’s hard to look at it, too.

What you see is not all you get

“Every pixel in astronomy has a source in it. We need to see every pixel. We’re nowhere close to that,” Bothun said. A short-term answer may be visualization walls, commonly called viz walls. These are banks of high-definition monitors that scientists could use to display and manipulate vast amounts of data in one place. This would be perfect for looking at such large, high-resolution images. If you’re seeing a scaled-down version of a photo, Bothun said, the really interesting stuff may simply get averaged out. In addition, it’s better to look at a entire image at native resolution. This will take some training of our brains, but they’re capable.

“Your brain is a great visualizing machine. It’s a great parallel processing machine,” Bothun said. He said if it wasn’t we couldn’t drive on I-5. Think about how it would be if you tried to consciously track the speed and location of every other vehicle around you on the freeway. It’s not possible.

“Your brain does this automatically,” Bothun said. “It’s about time we we started to do data analysis in a forum that matches your brain’s algorithm.”

This would allow us “to take on extremely challenging problems, which is what leads to discovery in science,” he added.

Star Trek to the rescue

Viz walls may not be enough when it comes to the data from LSST. Its ten-year survey of the universe will generate a mind-boggling 60 petabytes of information. To meet the challenge, Bothun’s office is working on advanced visualization tools, a sort of three-dimensional viz cloud.

“It could be the holodeck,” Bothun said in reference to the virtual reality facility in Star Trek. “That’s how you should think of this.”

In this viz cloud trained humans could look at data in real time, and quickly sort out and discard what isn’t useful. After all, Bothun noted, the scientifically interesting data is usually just a tiny fraction of what is collected, and there’s no good reason to be pack rats with the rest.

“If all we’re going to do is take the raw data set and write it to disk, this is not a useful instrument,” he said of the LSST. “We have to do business differently if we want to optimize discovery.”

Big data is here, and visualization of this sort will help astronomers, but it will go beyond that; It can help in fields from finance and business to medicine, climate change, and counter-terrorism. To make effective use of the information available will require solutions to the pipeline and database challenges.

“All of this is absolutely vital for observational astronomy to continue to progress and continue to engage in discovery,” Bothun concluded.

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Busy Presidents Day week ahead

Happy Presidents Day from Seattle Astronomy. We celebrate the birthdays of George Washington and Abraham Lincoln this week. Perhaps, though, we should observe Astronomers Day, because some big-name birthdays fall this week as well. Nicholas Copernicus was born Feb. 19, 1473—he would be 543—and Galileo was born Feb. 15, 1564—452 years ago this day. Maybe it is because of these two most important scientists that there are so many great astronomy events on the calendar this week!

Show me a rose

Rose City AstronomersWe’re planning a road trip to Portland, where the Rose City Astronomers will hold their monthly meeting at 7:30 p.m. Monday, Feb. 15 at the OMSI auditorium. Dr. Gregory Bothun of the University of Oregon will give a talk titled, “Astronomy, Big Data, and the Future.” The premise: we’re collecting astronomical data at an astronomically increasing pace, but human processing and thinking about all of this information can’t keep up. Is astronomy in danger of becoming a “pixel archive science?”

Silent Sky and These Things Abide

Silent SkyTaproot Theatre in Greenwood continues its run of Silent Sky, Lauren Gunderson‘s play about astronomer Henrietta Leavitt, through Feb. 27. This Tuesday, Feb. 16 at 7:30 p.m. the theatre will host a special conversation with the play’s director, Karen Lund, and Adrian Wyard of the Counterbalance Foundation as they discuss the search for truth by both science and religion, the history of the conversation between faith and science, and the possibilities for future dialogue. It’s free, but seating is limited, so contact the theatre if you wish to attend.

Watch for a post about our conversation with Wyard coming soon!

Decisions, decisions

There are two good events coming up on Wednesday, Feb. 17, but alas, you can only be in one place at a time, unless this whole multiverse thing is true.

AOT SeattleThe fine folks from Astronomy on Tap Seattle, organized by astronomy graduate students from the University of Washington, will host their monthly confab of astronomy, trivia, prizes, and beer at 7 p.m. at Bad Jimmy’s Brewing Company in Ballard. This month UW astronomer Dr. John Parejko will give a talk titled, “Detect the Ancient Universe Like a BOSS,” and Dr. Fabio Governato will speak about “Dark Matter, Black Holes and other reasons to work with NASA’s fastest supercomputer: Pleiades.” It’s free, but bring beer money.

Meanwhile the Seattle Astronomical Society will hold its monthly meeting at 7:30 p.m. Wednesday in room A102 of the Physics/Astronomy Building on the UW campus in Seattle. Astronomy Ph.D. student Phoebe Upton Sanderbeck will give a presentation about how measuring the temperature of the universe can help us understand its development.

Saturn’s moons of promise

Pacific PlanetariumPacific Planetarium in Bremerton will feature its monthly third Friday astronomy talk this Friday, Feb. 19 with hourly presentations at 5 p.m., 6 p.m., and 7 p.m. NASA Solar System Ambassador Ron Hobbs will share the latest findings about the environments on Saturn’s moons Enceledus and Titan, where liquid water and methane flow, which might provide the necessary conditions for life to develop. Tickets are $5 and are available at the door or in advance online.

The Mercury 13

Mercury 13Sally Ride became the first American woman in space when she flew on a space shuttle mission in 1983. More than two decades earlier 13 U.S. women were training for flight in the Woman in Space program. Of course, the Mercury 13 never got off the ground. At 2 p.m. this Saturday, Feb. 20 at the Museum of Flight aviation expert Philip Tartalone will explore the genesis of the Woman in Space Program, the personalities involved, the testing, and the social mores of the early 1960s that ultimately doomed the program. The presentation is free with admission to the Museum.

Up in the sky

Jupiter will be at opposition next month, but it’s already placed pretty well for viewing in the late evening these days. 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.

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Astronaut Wilson blazing trails to space

It’s interesting that so many people involved in space and astronomy can point to a particular moment when they became interested in the field as a career. For astronaut Stephanie Wilson it happened when she was about 13 years old.

Stephanie Wilson

Astronaut Stephanie Wilson spoke about her inspiration for pursuing a career in aerospace during a talk to participants in the Michael P. Anderson Memorial Aerospace Program Saturday at the Museum of Flight. Photo: Greg Scheiderer.

“I was given a school assignment to interview somebody who worked in an interesting career field,” Wilson recalled. “I was interested in astronomy at the time, so I interviewed an astronomy professor at Williams College.”

Wilson said she was fascinated by the opportunities to travel, do research, and teach to which a career in astronomy might lead.

“That was my first interest in space and my introduction to science,” Wilson said.

Wilson spoke Saturday at the Museum of Flight in a presentation to the Michael P. Anderson Memorial Aerospace Program. The program, named after the Washington-native astronaut who died in the space shuttle Columbia tragedy in 2003, aims to provide inspiration and role models for students who are underrepresented in aerospace.

“It really started a thought process about what other opportunities were available and what were some other ways that I could function in aerospace,” Wilson said of her talk with the astronomy professor. “I also had an inerest in working with my hands and understanding how devices are put together, so I did decide to study engineering in college.”

Statue of Mike Anderson

This statue of astronaut Michael P. Anderson is outside the Museum of Flight in Seattle. Photo: Greg Scheiderer.

She earned degrees in engineering science at Harvard and in aerospace engineering at the University of Texas. Wilson held jobs in structural dynamics, robotics, and spacecraft attitude control before becoming part of the astronaut class of 1996. She was the second African-American woman to fly in space, going on three shuttle missions to the International Space Station. During her presentation Wilson showed video of highlights of her STS-131 mission in 2010. She has logged 42 days in space, and hopes to go again. She said she’d especially enjoy a longer mission during which she could spend six months on the ISS.

Michael Anderson was part of the 1995 astronaut class, and Wilson met and flew with him during her early days with NASA. She said that gives her some extra affinity for his namesake aerospace program’s goals.

“I really hope that people see that, as a woman and as an engineer, I tried to worked hard in that field, I did the best that I could to advance those fields,” Wilson said. “I also hope that people see that I tried to make a path so that people could follow in those footsteps and continue on their work. I hope that young people will see that anything is possible.”

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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

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, becuase 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

Books by Fred Espenak

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Astronaut visit, three club meetings this week

A talk by a visiting astronaut and three astronomy club meetings highlight the week on the Seattle Astronomy calendar, and two of the week’s featured events are on the west side of Puget Sound.

Astronaut Wilson speaks at MOF program

Stephanie Wilson

Astronaut Stephanie Wilson. Photo: NASA.

Astronaut Stephanie Wilson, the second African-American woman to travel to space, will give a talk at 2:30 p.m. Saturday, Feb. 6 at the Museum of Flight. Wilson, who flew on three shuttle missions, appears in recognition of Black History Month and in conjunction with the Michael P. Anderson Memorial Aerospace Program, named after the Washington native astronaut who died in the space shuttle Columbia tragedy. The program brings in mentors for at-risk students and gives them exposure to aerospace education, improving their chances to graduate from high school.

The talk is free with admission to the museum.

Astronomy clubs meet

Three area astronomy clubs have their regular meetings scheduled this week.

The Olympic Astronomical Society gathers at 7:30 p.m. Monday, Feb. 1 in room Art 103 on the Olympic College campus in Bremerton. The club has a half-dozen interesting talks on its agenda for the evening.

Tacoma Astronomical Society will meet at 7:30 p.m. Tuesday, Feb. 2 in room 175 of  Thompson Hall on the campus of the University of Puget Sound in Tacoma. Popular speaker Ron Hobbs, a NASA JPL Solar System Ambassador, will give a talk about the DAWN mission to Ceres.

The Spokane Astronomical Society plans its monthly meeting for 7:30 p.m. Friday, Feb. 5 in the planetarium at Spokane Falls Community College. Guest speaker and program information hadn’t been published as of this writing.

First Friday Sky Walk

Pacific PlanetariumIf you haven’t checked out Pacific Planetarium in Bremerton, this Friday would be a good time to do so. The planetarium presents a First Friday Sky Walk each month, with the next being on Feb. 5. These family-friendly presentations give a look at what’s up in the night sky for the coming month. The first show is at 5 p.m. and it is repeated hourly through 8 p.m. Before or after shows you can explore the planetarium’s space science exhibits and activities. Volunteers from the Olympic Astronomical Society will be present to answer your astronomy questions.

Tickets are $3 and are available online or at the door. For those coming from the east side of the sound, the planetarium is less than a mile from the Bremerton ferry terminal.

Up in the sky

The Moon passes near Mars, Saturn, and Venus this week as the early-morning lineup of planets continues. 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.

Follow the Seattle Astronomy calendar to keep up to date on astronomy happenings in the area.

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SAS banquet Saturday, Leavitt play opens this week

An appearance by “Mr. Eclipse” and the opening of a play about noted astronomer Henrietta Leavitt highlight the events on this week’s Seattle Astronomy calendar.

SAS banquet

EspenakThe Seattle Astronomical Society will hold its annual banquet on Saturday, Jan. 30 at the Swedish Club on Dexter Avenue in Seattle. The keynote speaker for the event will be Fred Espenak, known as “Mr. Eclipse” for his long career tracking, viewing, and writing histories of eclipses. Espenak will speak about preparing to view the Great American Solar Eclipse, the total solar eclipse coming up in August 2017 that will be the first visible from the lower-48 since 1979.

Tickets for the banquet are sold out. Check our preview of the event from earlier this month.

Silent Sky opens at Taproot

FB_Silent_Sky_banner_lowline_700x259Silent Sky, the true story of the work of American astronomer Henrietta Leavitt, will have its Northwest premiere when it opens Wednesday at Taproot Theatre in Greenwood.

The play, written by Lauren Gunderson and directed by Karen Lund, will run through Feb. 27. Leavitt 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.

Remembering fallen astronauts

It’s hard to believe that Thursday marks the 30th anniversary of the explosion of the space shuttle Challenger that killed seven astronauts. Oddly enough, all three U.S. space disasters happened about this time of year. This Apollo I fire killed three astronauts on Jan. 27, 1967, and the shuttle Columbia was destroyed on re-entry on Feb. 1, 2003. The Museum of Flight pays tribute to the fallen fliers with its annual astronaut remembrance weekend this Saturday, Jan. 30.

The museum plans displays and video looking back at the events. NASA JPL solar system ambassador Ron Hobbs and Museum of Flight Challenger Learning Center coordinator Tony Gondola will give a presentation at 2 p.m. Saturday remembering the astronauts who paid the ultimate price in the line of duty.

Ready, Jet, Go!

Ready, Jet, Go!The Pierce College Science Dome and KBTC public television team up Sunday, Jan. 31 for a special event to launch the new PBS KIDS astronomy show Ready, Jet, Go! The event runs from 10 a.m. until 1:30 p.m. and includes hands-on science activities and screenings of the program at 10 a.m. and noon in the planetarium.

TAS public night

taslogoThe Tacoma Astronomical Society will hold one of its public nights at 7:30 p.m. Saturday, Jan. 30 at the Fort Steilacoom campus of Pierce College. The planned program will be about Apollo missions to the Moon. Club members will be on hand with telescopes for observing, weather permitting.

Up in the sky

The Moon passes near the star Regulus in the constellation Leo on Monday, Jan. 25 and flirts with Jupiter on Wednesday evening. 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.

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