Gravitational wave discovery ushers in new era in astronomy

“This is beginning a new era in astronomy,” said Ethan Siegel about the publication in February of a paper announcing that scientists had detected gravitational waves. Siegel has taught physics and astronomy at Lewis & Clark College and the University of Portland in Portland, Oregon. He is creator of the science blog Starts With a Bang, and is the author of Beyond the Galaxy: How Humanity Looked Beyond Our Milky Way and Discovered the Entire Universe (World Scientific, 2015). Siegel gave a talk at this month’s meeting of the Rose City Astronomers in Portland about what he calls the discovery of a lifetime.

Ethan Siegel

“This was something, when it was first proposed, that was really taken to be a preposterous consequence of a theory and something that we never really thought we were going to be able to test,” Siegel said. “We have gone in 101 years from pure theory to concrete, direct detection of gravitational waves.”

Einstein’s theory of relativity states that mass and energy bend spacetime, and that’s why objects orbit each other. Relativity explained anomalies in the orbits of planets in our solar system, but Siegel said there is an “extra weird” effect because the orbits decay.

“Another consequence of Einstien’s relativity is that as things spiral in, and it takes a long time to do, but as they do they emit a special type of radiation; they emit radiation that goes through the fabric of space itself,” Siegel said. “This is gravitational radiation.”

It takes way too long for that to happen here in the solar system. For Earth’s orbit to decay completely and merge with the Sun would take 10¹⁵⁰ years, according to Siegel. He said we’ll have to look elsewhere to see the effects happen on human-length time scales.

“You need to find heavy masses; heavier mass in relativity means a stronger effect,” Siegel said. “You need them to have small distances, where small distance is a few kilometers, not a few million miles. And you need them to orbit at fast speeds, where fast is kind of close to the speed of light.”

Luckily these conditions exist. Black holes, neutron stars, and pulsars can do the trick; the gravitational waves detected by the Laser Interferometer Gravitational-Wave Observatory (LIGO) last fall were generated by merging black holes. One of those black holes started out at 36 solar masses and the other at 29. After the merger they weighed in at 62 solar masses. That’s simple arithmetic: 36+29=65; what happened to the other three solar masses? Siegel said, oddly enough, this was a prediction by Einstein as well. It’s the flip side of e=mc².

“When these two black holes merged, three solar masses, about five percent of the total mass, was converted into pure energy,” he said. “That energy is the gravitational radiation and is why we here on Earth were able to detect this huge event of two black holes merging from over a billion light years away.”

Siegel is amazed that we were able to figure the mass, spin rate, merging speed, mass loss and other characteristics of these distant objects.

“We learned all of this information from one 20-millisecond signal that moved two laser arms by less than 10^-18 meters,” he marveled. “What I’d say we have now is a whole new way to discover our universe.”


That way is improving rapidly. The LIGO detectors at Hanford, Washington, and Livingston, Louisiana, are being tweaked to even greater sensitivity. New detectors are planned for Italy, Japan, and India. Siegel said the ultimate would be to build three huge LIGO detectors in space, forming an equilateral triangle in Earth’s orbit and having detector arms hundreds of millions of kilometers long.

“If you do that, you can not only watch things merge with supermassive black holes, you can find mergers of ultramassive black holes,” Siegel said. We might even be able to spot gravitational waves from cosmic inflation within the light of the cosmic microwave background. Siegel said if that happens, it would prove that gravity is a quantum force.

“There’s no way to make these fluctuations unless gravity is inherently a quantum force,” he explained. “The process that makes these fluctuations is a quantum process.”

Siegel said it’s a thrilling time to be involved in astronomy.

“This is the first time we’ve seen something astronomical without using a telescope or light of any type,” he said. “This is the dawn of astronomy beyond light-gathering telescopes.”

Chasing the 2017 total solar eclipse in Jackson, Wyoming

Jackson, Wyoming is cooking up a five-day festival to celebrate the total solar eclipse that will pass through town in August 2017. The nonprofit organization Wyoming Stargazing is at the center of the preparations. Its founder and executive director, Samuel Singer, says they’ll be doing several private viewing events, plus a big public party at the Jackson Center for the Arts. The center will also host a science and arts festival with events for several days before and after the eclipse.

Singer said the weather prospects for eclipse viewing in Jackson are good. While they often have afternoon thunderstorms, last summer they only had to cancel a small handful of their stargazing events.

“Typically we don’t have any cloud cover in the late morning/early afternoon, so there’s a good possibility that it’s going to be clear that morning for the eclipse,” Singer said, “but you just never know.”

In the event of bad weather they have a fail-safe option. Wyoming Stargazing is working with Teton Gravity Research, a company that makes extreme films of skiing and snowboarding. Their helicopter has a camera that will capture the eclipse.

“If it is cloudy, they’ll have the capability of projecting a real-time image down to the ground on a really big screen at the Center for the Arts,” Singer said.

Samuel Singer
Wyoming Stargazing Photo

“A lot of people are planning their driving routes out of the valley the night before if it looks like it’s going to be cloudy that morning,” he noted, “but Wyoming Stargazing is going to stick it out and we’re going to make the most of whatever happens.”

Jackson is a major tourist area, attracting around 10,000 visitors on the average summer day. Singer said that figure may double, or more, for eclipse week.

“It may end up being the single biggest tourism day in Jackson Hole history,” he said. Given that, lodging may be a challenge. Many rooms are already taken, but a lot of hotels are holding out for bookings with large organizations, while others don’t take reservations for more than a year in advance.

“Housing is going to be tricky,” Singer said. “I think that it’s definitely going to be one of the limiting factors on how many people can actually stay here for the week of the eclipse.” He added that there are likely to be lodging opportunities in the communities within an hour or two of Jackson.

Singer admits to a little bias, but he thinks Jackson will be one of the best places to see the eclipse.

“Jackson is probably one of the most beautiful places in the entire country,” he said, noting its spectacular mountains, undeveloped areas, and teeming wildlife. “There are no other places in the country that you can go to, see the eclipse, and probably see bison, moose, elk, black bears, grizzly bears, bald eagles, osprey, maybe some prong-horn antelope, and big-horn sheep.”

In other words, there’s a lot more to do than just watch the Sun disappear for a couple of minutes.

“There are lots of people who are traveling thousands and thousands of miles for those two minutes; in Jackson they can have a much bigger experience for their money,” Singer said.

Wyoming Stargazing is just three years old, but already is putting on about 200 observing events each year at resorts, schools, parks, and other venues. Conservation is also part of the organization’s mission.

“We’re working on preserving the dark night skies we have here in Jackson,” Singer said. “We’re really trying to provide some education for the community to help them understand why dark skies are important and what the adverse effects are of light pollution.”

They’re working with the public and the local city and county governments in trying to get good, dark-sky friendly lighting ordinances enacted.

“The long-term goal is to get Jackson recognized as a dark-sky community by the International Dark-sky Association, as well as to get Grand Teton National Park recognized as a dark-sky preserve,” Singer said. “The night skies are just the national parks above our heads, they’re part of the whole deal. It’s just another natural resource that needs to be protected. In Jackson, that’s kind of an easy sell because we have spent so much time and energy preserving the natural landscape, the views, the wildlife—and the dark night skies are just another part of what makes Grand Teton National Park so grand.”

Wyoming Stargazing also has big plans to build a state-of-the-art planetarium and observatory, which will house a one-meter telescope.

“I think it will be one of the largest instruments dedicated to public outreach anywhere,” Singer said. He hopes the project will be finished by the time of the eclipse, but expects it will probably take a little longer.

Singer has Northwest roots. He was bitten by the astronomy bug as a junior at Stadium High School in Tacoma, where he took an astronomy course from Mr. Jay Eastley. During his senior year the teacher encouraged Singer to build a Dobsonian telescope, and he was hooked.

Edible optics and fun science for BPAstro Kids

Astronomy club members are sometimes heard lamenting the graying of the hobby; young kids today are too interested in their electronic gizmos to look up at the night sky. Erica Saint Clair and the Battle Point Astronomical Association (BPAA) have embarked on a new effort to hook the kids while they’re young. The association has recently started BPAstro Kids, a program for younger children that precedes its monthly planetarium shows in the John Rudolph Planetarium at its Edwin Ritchie Observatory on Bainbridge Island.

Erica Saint Clair presents BPAstro
Kids programs for the Battle Point
Astronomical Association.

Though education and the planetarium have been part of the BPAA’s mission since its formation in 1993, the program for kids came about recently as something of an accident. Saint Clair took her youngest daughter to story time at the local library, and met another mom there whose husband makes regular presentations at the association’s events. She was recruited to do a talk about Mars rovers.

“I have no background in astronomy—zero,” Saint Clair said. “I have a Ph.D. in physics, which apparently qualified me.”

She did the talk, which took a lot of time to prepare and bored her five-year-old terribly. Saint Clair also has a two-year-old, and decided that she would prefer to make presentations for younger children.

“My passion is for teaching kids science, and making it fun, and making them want to do it and beg me to do it,” Saint Clair said. “It helps to have a five-year-old who is really into and really excited about everything we do in science.”

Thus BPAstro Kids was born, presented by “Dr. Erica,” who figured if she was already creating science activities for her own daughters, she might as well share with others. The sessions feature short talks followed by hands-on activities. The kids have built edible optics, Valentine’s “love bots,” and marble particle accelerators. This Saturday they’ll make real, working telescopes they can take home. They started with one session before the monthly planetarium show, but so many people brought their kids they’re doing two now.

“I feel like we’re snowballing, and that’s fantastic,” Saint Clair said. She’s working on turning her presentations into a science-education business. She’s founded Rosie Research, with the aim of engaging kids in new types of science labs. They may eventually make tools such as telescope-making kits available for purchase. In the meantime Saint Clair goes about the business of inspiring youngsters.

“My goal is to get kids interested in all types of science, and I think space science is kind of the go-to for kids,” she said. “Every kid wants to go to the Moon, every kid wants to see what Mars is going to be like.”

Saint Clair is encouraged by the interest in BPAstro Kids and said she feels we are beginning to value “smart” again.

“I think we are as a culture shifting towards ‘science is cool and it’s sexy and it’s fun,’” she said.

Kids can build telescopes at BPAstro Kids at 5 p.m. and 6 p.m. this Saturday, April 9 at the Edwin Ritchie Observatory in Battle Point Park on Bainbridge Island. Suggested donation is $5 to help cover costs. A presentation about space telescopes will follow at 7:30. BPAstro Kids has received financial support from BPAA, the Awesome Foundation, and Rotary International of Bainbridge Island.

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.

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.

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.