The annual Seattle Astronomical Society banquet and Astronomy on Tap Seattle are the highlight events for the coming week. The Museum of Flight kicks off Astronaut Remembrance Week, and regional planetarium shows cap the calendar.
The Seattle Astronomical Societybanquet always draws an excellent guest speaker, and this year is no exception: renowned photographer Robert Reeves will keynote the annual banquet, and talk in particular about observing and imaging the Moon. The banquet gets under way at 4 p.m. Sunday, January 28 at the Swedish Club on Dexter Avenue North in Seattle. Reservations are $65 for the general public, $55 for SAS members. Don’t wait; there were only 18 spots left as of this writing. Reservations are available online.
Reeves will do a special master class on lunar photography for the SAS Astrophotography Special Interest Group. The class is open to the public and will be held at 5:30 p.m. Saturday, January 27 in the Red Barn Classroom at the Museum of Flight.
Astronomy on Tap Seattle
The topic will be exploring alien moons when Astronomy on Tap Seattle holds its first event of the new year at 7 p.m. Wednesday, January 24 in the beer garden at Peddler Brewing Company in Ballard. Second-year UW graduate student in astronomy and astrobiology Tyler Gordon will speak about his research on the search for exoplanetary satellites using current and future telescopes. UW Ph.D. student in oceanography Max Showalter will discuss looking for life when the trail goes cold, an update on his work using movement as a sign of life in icy places.
Showalter did a talk at Town Hall Seattle almost two years ago. Check our recap of that talk and learn how SHAMU is helping hunt for ET.
The Washington State University Planetarium in Pullman has a new show this week titled, “Millions of Miles to Mars.” The show explores the whats, hows, and whens of Mars visits. Showtimes are 7 p.m. Friday, Jan 26, and 5 p.m. Sunday, Jan 28. Tickets at the door are $5 cash or check; they don’t accept credit cards. Kids under six get in free.
America’s three great spacefaring tragedies all occurred at this time of year. To honor the sacrifices of the fallen astronauts, the Museum of Flight holds an annual astronaut remembrance week. The event runs from Friday, January 26 through Sunday, February 4 and features displays and exhibits about the fallen astronauts and their accomplishments. Solar System Ambassador Ron Hobbs will give a presentation about the tragic missions, and about the risks and successes of space travel, at 2 p.m. Saturday, January 27. It’s free with museum admission.
A total eclipse of the Moon will be visible in the early morning hours of Wednesday, January 31. The event begins just after 3 a.m. PDT, the partial eclipse starts around 3:45, and it will be total from just before 5 a.m. until a little after 6:00. All you really need to do is go outside and look up, but if you want to watch with others, the Seattle Astronomical Society plans a group viewing event at Solstice Park in West Seattle.
You can always scout out future events on our calendar.
Professor Erika Harnett opened the evening explaining the overall work of NASA’s Virtual Planetary Laboratory, which is headquartered at the UW.
Erika Harnett (Photo: Greg Scheiderer)
“We use a variety of techniques to study planets found in our solar system and in other solar systems for their potential habitability, the potential for life developing there,” Harnett explained.
Harnett’s particular research interest is on the vanishing atmosphere of Mars. Rovers there have helped us confirm that, while the Red Planet is now cold and arid, it was once warm and had oceans and flowing rivers. It also once had a global magnetic field, but it doesn’t any more.
“At some point in Mars’s history—and we’re really having a hard time telling when—its global magnetic field disappeared, and at that point its atmosphere was fully exposed to the radiation of space,” Harnett said. “Probably at that point it started losing a large amount of its atmosphere to space and that’s when water stopped becoming stable.”
There’s lots of ice at the poles and underground on Mars, but if warmed it would go straight to vapor because of the low atmospheric pressure.
Harnett and others are working to figure out the time line for if and when Mars was habitable.
Space is big
While we’ve been to Mars robotically and may well go in person one day, Harnett noted that space is big and there aren’t that many other places to go where life might be possible. For the rest of the universe we use remote sensing.
“We train telescopes looking at a variety of wavelenghts at those locations and try to see what kind of information we can read from those wavelengths of light,” she said.
We can figure out a lot even from a little bit of light. Aliens looking at Earth from afar might conclude that the blue light means lots of water. They could measure our rotation by tracking light changes. Green or brown light might mean vegetation while white would be an indicator of ice. We could use similar methods learn such things about exoplanets far away.
Life on Jupiter’s moons
Marshall “Moosh” Styczinski is a UW graduate student who said he first got interested in Jupiter after watching the movie 2001: A Space Odyssey. Jupiter is still his favorite planet.
Moosh Styczinski (Photo: Greg Scheiderer)
“Its got these four big moons that are a great place to start looking if we want to find life elsewhere in the solar system,” Styczinski said. The focus is on Europa, but the other Galilean moons play a part as well.
“Io plays a surprisingly big role in both why Europa is a promising place to look, and how we study it,” Styczinski noted. Io is pockmarked with volcanoes and its surface is coated with sulfur spewed from those volcanoes. The moons are heated internally because of tidal heating and orbital heating, and not just on the rocky moons.
“Tidal heating causes friction in the interior that warms up the rocks and melts the ice from the underside,” Styczinski explained. “The ice forms a thick crust on top that acts like a blanket, keeping the water warm from the cold space outside.”
Life needs more than just water. Europa also probably has nutrients because liquid water comes into contact with hot rocks.
“Hydrothermal vents are what makes Europa an exciting place to look for life,” Styczinski said. “It has all the basic ingredients that life needs: an energy source, nutrients, water, and shelter.”
We’ve learned a lot about Europa and made models based on our observations so far, but we need more data to get a better handle on questions like the inner structure of this moon, how deep the water is, and where geysers and hydrothermal vents might be found. The Galileo probe is no more, but a couple of other missions are on the drawing boards. NASA plans to launch the Europa Clipper some time in the next decade, and the European Space Agency is scheduled to launch JUICE—Jupiter Icy Moons Explorer—in 2022.
“Both of these missions are going to visit Europa many times, and return lots of valuable measurements that can help refine our models,” Styczinski said. “Finding the right model for Europa’s interior can directly guide future missions by telling them where to go and what we might find when we get there.”
We know for certain of some 2,500 exoplanets—planets orbiting stars other than our own Sun—and there are about five thousand more possibles, of which UW grad student Brett Morris, a co-founder of Astronomy on Tap Seattle, expects about 95 percent will also be confirmed as planets. Most of these have been discovered by the Kepler telescope observing a dip in the light when an exoplanet transits in front of its host star. Morris said this discovery is not really so tricky as it sounds.
Brett Morris (Photo: Greg Scheiderer)
“Probably even your iPhone camera is good enough to measure the change in brightness of the Sun when something goes in front of it,” he said. “If you just measure the brightness of the star instead of actually resolving the surface and seeing things going on, you can discover planets.”
Morris said that for every exoplanet the size of Jupiter, they’re discovering two that are about the size of Neptune and a dozen that are roughly the size of Earth.
“The big suprise is that the most common type of world is one that we don’t know anything about,” Morris said. A great many exoplanets have been discovered that are somewhere between the size of Earth and Neptune, which is about four times the diameter of the home planet. Since we don’t have any of these “mystery worlds” of that size in our solar system, the first thing astronomers want to figure out is at what size point these planets are more likely to be gaseous than rocky.
“Exactly where that line is will determine how much habitable real estate there is in the universe,” Morris said, as we don’t expect anyone or anything to be living on gas planets.
Morris is looking forward to the launch of the James Webb Space Telescope, now scheduled for next year. JWST will see in infrared, and will examine spectra of light from the atmospheres of exoplanets to reveal the elements that exist there.
“What we hope to look for are oddballs,” Morris said. Earth, for example, is the oddball of our solar system. While Venus and Mars have atmospheres of mainly carbon dioxide, ours is rich with nitrogen, oxygen, and a host of trace elements.
“Life is what causes the atmosphere here to be different,” Morris said. “We might have trouble saying whether or not life is to blame if we were looking at planetts in other solar systems, but we could definitely flag that one and then try to study it harder, because something interesting is going on there.”
After the talks we watched the 3-D movie The Search for Life in Space. The film is visually spectacular. One often had the notion that a moon or the Cassini spacecraft were about to land in the next seat. It’s worth a look if you get a chance. It’s showing at Pacific Science Center at least through January. Check out the trailer below.
As we flip the calendar to December, there are a couple of good headline events, four astronomy club meetings, and several educational events to look forward to.
Astronaut and mountaineer Scott Parazinski is the only person ever to have both flown in space and stood on the top of Mount Everest. He’ll be at the Museum of Flight at 2 p.m. on Saturday, December 9 to talk about his experiences and his new book, The Sky Below: A True Story of Summits, Space, and Speed (Little A, 2017). Parazinski will sign copies of the book after his talk, which is free with museum admission.
If you can’t make it Saturday, you can pick up the book by clicking the link above or the book cover at left; Seattle Astronomy gets a small royalty at no cost to you when you purchase this way, and it helps support our operations. Thanks so much!
Life in Space
The Pacific Science Center’s Science in the City lecture series continues at 7 p.m. Wednesday, December 6 with a program called Life in Space. Three University of Washington astrobiologists will discuss their research—including the search for planets around other stars, characterizing how stars influence the habitability of those planets, and techniques to mix computer modeling with data analysis to determine the characteristics of potentially habitable worlds. Two of the three presenters will be familiar to Seattle Astronomy readers. Brett Morris is a PhD candidate of astronomy and astrobiology at the University of Washington and is a co-founder and co-host of the popular Astronomy on Tap Seattle events. Dr. Erika Harnett is a research associate professor and was featured on the blog and podcast this year. The “new guy” is Marshall “Moosh” Styczinski, a grad student who does research using magnetic fields to peel back the icy crust of Jupiter’s moons, looking for places that life may be found.
After viewing the documentary The Search for Life in Space, the trio will answer questions about their research and other topics addressed in the film.
Tickets to Life in Space are $5, free for Pacific Science Center members.
In addition, two clubs have public outreach events on Saturday. The BP Astro Kids on Bainbridge Island will make LED holiday cards during sessions at 4 p.m. and 5 p.m. at the Ritchie Observatory on Bainbridge Island. Following at 7:30 p.m. the Battle Point Astronomical Association monthly planetarium show will focus on how neutron stars make gold, and how we can tell they’re doing it. The Tacoma Astronomical Society will hold one of its public nights at 7:30 p.m. Saturday, December 9 at the Fort Steilacoom campus of Pierce College. The indoor presentation will be a viewing of the movie The Christmas Star. At both the Battle Point and Tacoma events there will be stargazing if the weather permits.
There’s a full Moon on Saturday and Daylight Saving Time ends on Sunday. Maybe that’s why the astronomy calendar is a little sparse this week!
Are we alone in the universe?
Thousands of exoplanets have been discovered over the past two decades. Dr. Lisa Kaltenegger, Director of the Carl Sagan Institute at Cornell University and an associate professor in Cornell’s astronomy department, will discuss these discoveries during a lecture at 5:30 p.m. Friday, November 3 at Adler Planetarium in Chicago. You don’t have to be in the Windy City to attend; the lecture is part of the bi-annual Kavli Fulldome Lecture Series and will be live streamed to the Pacific Science Center’s Willard Smith Planetarium! It’s part of the center’s on-going Science in the City lecture series. Kaltenegger will explore how we can determine which exoplanets might be suitable for life and cover techniques and missions that could detect life on these faraway worlds.
Tickets are $5, and free to science center members. Space is limited, so advance tickets are recommended.
The Spokane Astronomical Society will meet at 7:30 p.m. Friday, November 3 at the planetarium at Spokane Falls Community College. The guest speaker had not been published as of this writing.
The Seattle Astronomical Society will offer one of its new members orientation sessions at 2 p.m. Sunday, November 5 at the Theodor Jacobsen Observatory on the University of Washington campus in Seattle. While the title calls out “new members,” prospective members are welcome as well. It’s a good time to find out what the society has to offer—and sign up!
Baron saw his first total solar eclipse from Aruba in 1998.
“I was just dumbfounded,” he said at the sight of the eclipse, which revealed stars in the daytime and Jupiter, Mercury, and Venus. “There, among the planets was this thing; this glorious, bewildering thing. It looked liked a wreath woven from silvery thread and it just hung out there in space, shimmering.”
It was the Sun’s corona, and Baron said the photos you’ve seen don’t do it justice. Soon, the eclipse was over.
“The world returned to normal, but I had changed,” Baron said. “That’s how I became an eclipse chaser.”
He said he decided that day, on the beach in Aruba, that he wanted to write a book about solar eclipses. He also figured 2017 would be the year to release it, with public interest in solar eclipses likely to be at its apex because of this year’s eclipse. So his book has been 19 years in the making. He said the work started in earnest about seven years ago, when he went researching for interesting eclipse stories to tell.
The American eclipse of 1878
Baron came upon a historical marker next to Battle Lake in the Wyoming Sierras, which claims that Thomas Edison came up with the idea to use bamboo as a filament for an electric light bulb while fishing at the lake in 1878. Baron found no evidence that this was actually true, but Edison was involved in eclipse watching in Wyoming that summer, for the total solar eclipse of July 29, 1878. The eclipse ran from Montana south down across the American frontier through Texas. At the time, Baron noted, Europeans were the clear leaders in eclipse science.
“Here was America’s chance to shine—or an opportunity to slip up and embarrass ourselves—but if all went well we would show the rest of the world what we were capable of as a scientific nation,” Baron said, “and so the eclipse was a big, national undertaking.” The eclipse and the expeditions to observe it received in-depth coverage in the newspapers.
Edison was among a group that went to Rawlins, Wyoming to view the eclipse. The group included Norman Lockyer, who had discovered helium on the Sun and founded the journal Nature; and James Craig Watson, an astronomer at the University of Michigan, who was in search of the hypothetical planet Vulcan that could explain orbital anomalies of Mercury.
Author David Baron spoke about his book American Eclipse on July 19, 2017 at the Pacific Science Center. (Photo: Greg Scheiderer)
Also out west was Maria Mitchell, professor and director of the Vassar College Observatory, who brought a group of Vassar students to Denver to show that women could do science, too. For Edison’s part, he was anxious to test an invention he called the tasimeter, intended to detect minuscule changes in temperature. Astronomers were interested in the device, which might reveal if the Sun’s corona gave off heat.
“These three main characters of mine had a lot on the line,” Baron said, and on the day of the eclipse they declared great success and the press was highly positive, though neither Edison, Watson, nor Mitchell really achieved their set goals.
“Maria Mitchell did help open the doors of science and higher education to women, but it’s not like male scientists suddenly embraced their female counterparts,” Baron noted. “It was the beginning of a long, hard, continuing struggle.”
Watson didn’t find Vulcan, of course; the precession of Mercury’s orbit was explained later through Einstein’s general relativity. Edison’s tasimeter never lived up to the hype. He did head home and start work on the light bulb, though not in the way the Historical Landmark Commission of Wyoming would have you believe.
“The eclipse of 1878 did not illuminate America in the way the historical marker claims,” Baron said. “However it did enlighten America, helping to push this upstart nation toward what it soon would become—the undeniable global superpower in science, a country that would, in this intellectual realm, eclipse the world.”
Learning from history
Baron sees an interesting parallel with next month’s total solar eclipse.
“Once again the Moon’s shadow will visit us at an interesting time in our intellectual development,” he noted. “Today the issue isn’t whether America can rise up and take on the world in science, the question is whether America can maintain its global lead.”
It will undoubtedly be the most widely viewed total solar eclipse in human history. We’ll see whether it has the power to change hearts, minds, and the course of history.
You can purchase American Eclipse though the link above or by clicking the image of the book cover. Purchases made through links on Seattle Astronomy support our ability to bring you interesting astronomy stories. Thank you!
The 21st Century is an exciting time for those who study exoplanets. As the number of confirmed worlds in orbit around far-away stars grows almost daily—as of this writing the NASA Exoplanet Archive lists 3,489 of them—Lucianne Walkowicz says it’s becoming more than just a tally.
Adler Planetarium astronomer Lucianne Walkowicz gave a talk titled “Seeking Life Beyond Earth” May 23, 2017 at the Pacific Science Center. (Photo: Greg Scheiderer)
“We are starting to get to know these planets not just as a new marble in the bin, but something that you can understand what its environment might be like,” Walkowicz said. “We’re right around the corner from being able to really understand these places as worlds, and not just compare their size or their orbit to the planets in our solar system.”
Walkowicz is an astronomer at the Adler Planetarium in Chicago who earned her master’s and doctoral degrees at the University of Washington. She was back in Seattle recently to give a talk at the Pacific Science Center about the latest in exoplanet research and the prospects for figuring out if life exists on any of them. The talk complemented the Mission: Find Life! astrobiology exhibit that is presently running in the center’s Portal to Current Research space. (Check our previous post and podcast for more about the exhibit.)
While a majority of the early exoplanet finds by the Kepler mission were of gas giants on the order of Jupiter, Walkowicz said that was because bigger planets are easier to find because they block more light when they pass in front of, or transit, their host stars.
“The smaller planets that are more like Earth that might be out taking a full year to go around their star are even harder (to find) because you have a very small signal that takes years and years to repeat,” she said. As time went on, more and more smaller exoplanets were detected.
It turns out that, “The things that are a little bit bigger than Earth and little bit smaller than Neptune are super common,” Walkowicz noted. This threw planetary formation theorists for a loop. They’d spent careers constructing formation models that did not result in planets of that size because we don’t have any in our solar system. While journalists tend to rush toward a declaration of some of these planets as “Earth-like,” Walkowicz said that’s typically premature.
“It’s not the discovery of life around other stars,” she said of the finding exoplanets in this size range, “but it does mean that there is a lot of real estate for us to look.”
Goldilocks lives in the habitable zone
Walkowicz discussed the concept of the so-called habitable zone around stars—an area that could be at the right temperature for liquid water to exist on a planet’s surface. This is a ballpark figure; she noted that distant astronomers looking at our solar system would declare Venus, Earth, and Mars all to be within our Sun’s habitable zone. Yet these are very different worlds and two of them are not particularly hospitable at present. The type and kind of starlight, a planet’s orbit, tidal heating, radiation protection, and the actual existence of water, ice, haze, or clouds all can make big differences for a planet’s potential habitability.
As we move forward, astronomers will look not just at exoplanets’ location, but also at their biosignatures, which Walkowicz explained are the, “signatures of the chemical species that make up a planet’s atmosphere and whether they mean that life can be there.” Finding oxygen, ozone, water, carbon dioxide, and methane all could be positive indicators for life. On the other hand, finding carbon monoxide in a planet’s atmosphere would mean life is less likely. But even the right ingredients don’t necessarily mean life exists.
Local help from VPL
The Virtual Planetary Laboratory (VPL) at the University of Washington is leading the way in looking at such biosignatures and interpreting what they could mean for varying planets around different types of stars. Having so many possible combinations can be on the confusing side.
“Planets are complicated,” Walkowicz said. “They’re not just spheres orbiting around a star that’s getting some illumination at some distance.”
“It’s usually just not one thing, its the balance of things overall. You have to be able to look at the complete picture in order to interpret what you find,” she added.
That is difficult to do at present, but a couple of future space telescopes will be able to help. The Transiting Exoplanet Survey Satellite (TESS) is scheduled to launch next March, and the James Webb Space Telescope is targeted for launch in October 2018. TESS will look for more exoplanets by watching for their transits in front of some 200,000 nearby stars. The Webb, according to Walkowicz, will look into the infrared and explore the plentiful small, red stars in the galaxy and try to take the spectra of the atmospheres of planets in orbit around them.
“In some cases, we’ll be able to get this chemical fingerprint of what the planet’s atmosphere is made up of,” Walkowicz enthused. She added that the VPL’s work will help astronomers decide which planets to study with the new space telescopes—it will be important to winnow the field down to the most promising candidates, as competing demands for time on these scopes will limit the observing opportunities for any one project.
We might well have a better idea if there’s life elsewhere in the not-too-distant future.
It’s been a month filled with astronomy at Pacific Science Center, and they’ll wrap it up big this weekend with their celebration of AstronoMay Saturday, Sunday, and Monday. According to Dave Cuomo, supervisor for science interpretation programs and the Willard Smith Planetarium at the center, there will be a lot going on.
“We will have expanded planetarium shows,” Cuomo said. “We will have lectures about astronomy featured on our Science on a Sphere exhibit. We will talk about astrobiology in some of those. We will have space scientists that visitors can speak with and talk about their study and research about astronomy. And, weather permitting, we will have some solar telescopes out so you can safely observe the Sun.”
There’s a great variety of selections for shows in the planetarium. One that will run this weekend is called “The Search for Life.”
“It will be an exploration of the different ways that astrobiologists are looking for life, both in the solar system and outside of the solar system,” Cuomo said. That show is a great complement to the “Mission: Find Life!” exhibit about astrobiology that is presently in the center’s Portal to Current Research space. (See our post from last month for more about that.) Another show, titled “Let’s Explore Light,” is about the basic physics of light.
A third planetarium show called “The Skies of Ancient China,” created to complement the popular Terracotta Warriors exhibit at the center, looks at more than 4,000 years of Chinese astronomy. Cuomo noted that Chinese astronomers in the day had a pretty high-stakes job.
“They were hired by the emperor because the emperor ruled the Earth because he had the mandate from the heavens,” Cuomo explained, “so he needed to be able to know what was going to happen in the sky.”
The astronomers predicted planetary conjunctions and eclipses of the Sun and the Moon. Conjunctions in particular were considered omens of pending regime change, and, say what you will about whether the heavens influence lives on Earth, a couple of empires actually did flip at around the time of a conjunction. More amazing is the accuracy of both the Chinese astronomical observations and their record keeping.
“Modern astronomers have associated at least nine supernova remnants with ‘guest stars’ that the Chinese observed and recorded the location of,” Cuomo marveled. “There is also almost two thousand years of history of a returning star every 76 years, which we now know was Halley’s Comet.”
Cuomo found it interesting that there wasn’t much mythology around the heavens with the Chinese astronomers as compared to that in many other cultures. He and three of the center’s planetarians created the show with research help from the British Library, the Hong Kong Space Museum, and many others across the country and the world.
The astronomy doesn’t stop once May ends. The Pacific Science Center is gearing up for the total solar eclipse that will happen on August 21. The entire month of August will be PacSci “Up in the Sky.”
“We will talk about solar astronomy, observational astronomy, weather; anything that you look up to see, we’ll want to talk about,” Cuomo said. They’ll also have eclipse glasses on hand for safe viewing of the Sun, and probably some solar projectors for watching the eclipse.
Although the eclipse will only be partial in Seattle, the center plans to open early, at 8:30, that morning.
“We will have solar telescopes available and educators talking about the eclipse and the science of the eclipse,” Cuomo said. First contact—when the Moon starts moving across the face of the Sun—will happen at 9:08 a.m. at PacSci, and it will be over by 11:30. But they’ll have live feeds from other eclipse events from all across the country so you can keep watching.
Cuomo will be in Madras, Oregon for the total eclipse, along with other educators from the Pacific Science Center in partnership with Lowell Observatory. They’re leading a four-day trip to view the total eclipse. Space is limited; if you’re interested in going along, you can find out more online.