Category Archives: lectures

Seattle Astronomy calendar, week of April 6

A salute to the Mercury Seven, plus a planetarium show and Yuri’s Night highlight the Seattle Astronomy calendar for this week.

Mercury Seven

The Mercury Seven. Front row L-R: Schirra, Slayton, Glenn, and Carpenter. Back row: Shepard, Grissom, Cooper. Photo: NASA.

It was 56 years ago April 9, in 1959, that NASA announced which men had been selected as the Mercury Seven, the first group of U.S. Astronauts. The seven were Scott Carpenter, Gordon Cooper, John Glenn, Gus Grissom, Wally Schirra, Alan Shepard, and Deke Slayton. The death of Carpenter in 2013 left Glenn as the only living member of the original astronaut corps.

Tom Wolfe’s book The Right Stuff is a fascinating telling of the story of the astronauts, and the 1983 movie version of the book, directed by Philip Kaufman, is fantastic as well. I still chuckle at the cast names: Ed Harris played John Glenn, Scott Glenn portrayed Alan Shepard, and Sam Shepard was cast as Chuck Yeager. There’s also a local note on the film; Seattle actress Pamela Reed portrayed Trudy Cooper, Gordo’s wife. Reed recently had a recurring role in the TV series Parks and Recreation, and was on the Seattle stage as Martha in Who’s Afraid of Virginia Woolf? at the Seattle Rep last year.

Yuri’s Night

LogoYurisNight_WHITEring_TRANSPARENTbackground250x250Sunday, April 12, marks the 54th anniversary of human spaceflight. On that date in 1961 Russian cosmonaut Yuri Gagarin became the first person launched into space. Worldwide on and around this date there are many observances of Yuri’s Night to commemorate the feat.

Only two area events are registered on the Yuri’s Night website. The Seattle Chapter of the National Space Society will meet at 7 p.m. Sunday, April 12 at the Museum of Flight, and a Yuri’s Night observance will be held next Saturday, April 18 at 5 p.m. at the Pearson Air Museum in Vancouver, Washington.

Club events

At lot of eyes were on the sky on April 11, 1986 when Halley’s Comet made its closest approach to Earth during its most recent visit to the inner solar system. Area clubs will be looking skyward this Saturday to mark the date.

The Everett Astronomical Society holds its monthly meeting at 3 p.m. April 11 at the main downtown branch of the Everett Public Library. Program details had not been announced as of this writing.

That evening beginning at 7:30 the Battle Point Astronomical Association hosts a planetarium program and evening of observing at its Edwin Ritchie Observatory in Battle Point Park on Bainbridge Island. The program topic is telescopes: the great ones of history, new ones on the drawing boards, and which one is right for you. Club members will be on hand with scopes for observing if weather permits.


General relativity explained

Cool news from the Seattle Astronomical Society, which just announced that the program for its April meeting will be a talk by Dr. Jeffrey Bennett, author of What Is Relativity?: An Intuitive Introduction to Einstein’s Ideas, and Why They Matter (Columbia University Press, 2014).

Bennett has spent much of the last 30 years at the University of Colorado, where he remains an adjunct research associate with the Center for Astrophysics and Space Astronomy. These days he is mainly a writer and he has embarked on a “Relativity Tour” this year, celebrating the centennial of Einstein’s revolutionary ideas. Bennett’s basic premise is that general relativity is not all that difficult to grasp, and his goal is to bring relativity out of the realm of obscure science and help us understand it and the impact it has on our lives.

Oddly enough, it appears that my cats understand relativity. Followers of the Seattle Astronomy Facebook page recently saw the photo below of their demonstration. People trying to help others understand general relativity often ask them to imagine a bowling ball on a bed sheet. In this case Archie and Theodolinda used themselves as the massive objects, and the down comforter represents space-time. The green object in the background may be Neptune.

relativitycatsBennett’s explanation may not be simple enough for cats to understand, but it is advertised as suitable for anyone from middle school on up. Bennett has taught young kids, and in addition to scholarly textbooks and science tomes for adults, he has written a series of children’s books featuring the outer space adventures of Max the dog. To gear up in advance of the talk pick up What Is Relativity? by clicking this link or the photo above. Links to Bennett’s other books are below.

The Seattle Astronomical Society talk will be at 7:30 p.m. Wednesday, April 15 in room A102 in the Physics/Astronomy Building at the University of Washington in Seattle. In addition to SAS, the Relativity Tour is sponsored by Big Kid Science, Columbia University Press, Fiske Planetarium, and Story Time From Space.

More materials

Jeffrey Bennett website

Books by Bennett


Gamma ray bursts, galaxies, exoplanets, and beer

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

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

Zapped by gamma rays

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

Astronomy on Tap

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

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

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

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

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

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

Astronomy porn

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


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

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

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

Little green men

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

Enceladus geysers

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

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

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

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

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

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


An evening with famed comet hunter Don Machholz

In an age when automated programs are scanning the night sky using high-tech telescopes, CCD cameras, and computing power to find near-Earth objects, Don Machholz continues to search for comets the old-fashioned way.

“I do it visually,” Machholz explained at the annual banquet of the Seattle Astronomical Society last month. “I do not use cameras, I do not use CCDs. I look through the eyepiece and I push the telescope.”

Scheiderer and Machholz

Seattle Astronomy’s Greg Scheiderer, left, with comet hunter Don Machholz at the Seattle Astronomical Society’s annual banquet. Photo: Greg Scheiderer.

Machholz is the record holder, with eleven comets discovered visually since he started his hunt in the mid-1970s. That doesn’t sound like so many, but consider this: according to the Catalog of Comet Discoveries, there have been 1,502 comets discovered since 2005. Of those, just three have been discovered visually. The Panoramic Survey Telescope & Rapid Response System (Pan-STARRS) got full or shared credit for thirty-three comet discoveries last year alone. The last time a comet was discovered visually was in 2010, when there were two, and Machholz bagged one of those.

There’s a little bit of luck involved in comet hunting. Machholz jokes that the first thing you need to do to find a comet is to be looking where it is in the 40,000 square degrees of sky. But he has a system. He checks websites to figure out where the programs like Pan-STARRS are looking on a particular night and then conducts his hunt in a different part of the sky. Machholz divides the sky into sections, and makes telescope sweeps covering about fifteen degrees at a time. Then moves down about a half field of view and sweeps again. He keeps meticulous records of his searches.

“It sounds boring, but you get to see a different part of the sky all the time,” Machholz said.

He got interested in astronomy as a boy. His father was a naval navigator and had a book with star charts that Don used to learn the sky. When he was about eight years old his sister brought home a book about meteors that piqued his interest. Finally, Machholz received a telescope for his thirteenth birthday. On the third night out he found Saturn.

“I could see the rings on it,” he recalled, thinking stargazing might not be such a bad hobby. He was hooked.

A family tragedy helped drive Machholz’s comet-hunting program early on. In 1976 his brother, an avid skier, was killed in an avalanche. Machholz found himself depressed, with insomnia, sleeping just a few hours a night, but with lots of energy.

“That’s kind of the ideal ingredients for a comet hunter,” he said. “For the next three or four years my comet hunting program developed to a greater and greater depth. Comet hunting wasn’t just something I did, it became part of who I am.”

His early comet hunting was done from his parents’ back yard and other locations around Concord, California. After moving to San Jose in 1976 he did much of his observing from nearby Loma Prieta mountain. In 1990 he moved to Colfax, California and built an observatory there.

After so much time at the eyepiece, Machholz says his heart still skips a beat or two when he thinks he has found a new comet.

“It’s a very important moment,” he said. “First I want to remember what song was on the radio.” He always has the radio playing when he hunts, and his presentation was full of music from the Rolling Stones and the Beatles to Phil Collins and Cyndi Lauper. He adds, though, that there’s no time for jumping up and down when he finds a comet, because there’s serious work to do.

“You don’t want to lose it,” he explained. “You might have it in the field now, but if you bump the telescope or let too much time go by and it drifts out of the field, you have to be able to find it again.”

“You have to be sure you know where you’re looking, make sure it’s not a galaxy or a cluster,” he added. He double checks with his star atlas, makes a drawing that puts the comet in its position compared to the field of stars, and watches to see if it moves. If all that checks out he reports the discovery by email, phone, and fax.

96/P Machholz

Comet 96/P Machholz as seen by the HI-2 camera on the STEREO-A spacecraft.

Of all of his discoveries, Machholz said comet is 96P/Machholz is his favorite.

“It is an amazing comet; it has its own Facebook page,” he said.

The orbit of 96/P Machholz changes because of the influence of Jupiter, and the perturbations have some scientists thinking there may be large undiscovered planets way out beyond Pluto. The comet also is low on carbon and cyanogen. This hasn’t been explained, though the leading ideas are that it may have originated in another solar system, or been exposed to temperature extremes that changed its chemical composition.

It was a pleasure to spend an evening with Don Machholz. His lively presentation was full of humor and had the banquet audience laughing and engaged.


Rosetta mission: the end of the beginning

There have been a lot of amazing space missions that rank among the greatest engineering achievements of all time. The Rosetta mission has to be one of the most impressive ever. Rosetta traveled 10 years and more than four billion miles to rendezvous with comet 67P/Churyumov-Gerasimenko, a rubber-ducky-shaped pile of rocks 2.5 miles across that is zipping through space at about 84,000 miles an hour. It went into orbit around the comet and then it dropped a lander, Philae, that touched down on the surface of the comet back in November. Never mind that Philae didn’t stick the landing; that’s an quite an accomplishment.

Paul Weissman

Paul Weissman of JPL spoke about the Rosetta mission Monday at the 225th meeting of the American Astronomical Association.

Thus it was most enjoyable to hear from one of the Rosetta mission scientists, Paul Weissman of the NASA Jet Propulsion Laboratory, on Monday afternoon at the 225th meeting of the American Astronomical Society. Weissman gave a talk titled “Back to the Beginning: The Rosetta Mission to Comet Churyumov-Gerasimenko.”

“Doing space missions is a work of delayed gratification,” Weissman quipped, noting that they actually started work on Rosetta in 1996, and adding that there had been plans for such a mission for about a decade before that. They finally launched in 2004 and arrived at the comet, often shortened to C-G for obvious reasons, back in August.

“We had been ten years in space,” Weissman said. “It was really exciting to finally arrive at the comet.”

Rosetta carries 11 scientific instruments on board, and the Philae has ten. Even though Philae didn’t operate for long, between them the two craft have sent back a wealth of data.

“We’ve just been flooded with phenomenal results,” Weissman said.

Philae on C-G

Rosetta’s lander Philae on the surface of Comet 67P/Churyumov-Gerasimenko. One of the lander’s three feet can be seen in the foreground. The image is a two-image mosaic. Credit: ESA/Rosetta/Philae/CIVA

He shared a great many photographs from the mission and explained what all of the instruments have been observing. Among the interesting discoveries are that C-G is spinning faster than it did on its previous trip around the Sun, the result of the forces of outgassing of the comet’s material. There are pits on the nucleus that may be sink holes or outbursts; they’re not quite sure yet. They’ve detected water within the comet, and learned it is colder in its interior than on the surface. And the comet has about 74 percent porosity.

Some of the most fantastic returns are images taken by Philae from the surface of C-G that show exquisite detail.

“We’re looking at millimeter resolution of the surface of the comet,” Weissman noted, “something that’s just astounding in terms of what we’ve been able to do previously.”

Weissman holds out hope that they’ll get more from Philae, even though its batteries are dead because it landed in the shade.

“It may be possible to re-awaken the lander in May of this year,” he noted. “The solar panels that are exposed will gather enough energy to charge up the batteries, and we might have another shot of making measurements with the lander.”

Whether that works or not, there already is a great deal of data that mission scientists simply have not yet had time to analyze, and there’s more to come.

“This is the end of the beginning,” Weissman said, “because we have another whole year that we’re going to be in orbit, studying the nucleus and watching it get active. It reaches perihelion in August, so we’ll also watch it get inactive. And there’s talk of an extended mission into 2016.”

“This is just a remarkable mission.”


A dim view of the future of funding for space exploration

Dr. John M. Logsdon does not paint a very optimistic picture of the future of funding for space exploration. Logsdon, considered the dean of space policy and the founder of the Space Policy Institute at George Washington University, gave a talk titled “What Do We Expect of a Space Program?” today at the 225th meeting of the American Astronomical Society in Seattle.

John Logsdon

Dr. John Logsdon speaking Jan. 5, 2015, at the 225th meeting of the American Astronomical Society in Seattle.

Logsdon pulled the title of his lecture from a line in a Nixon Administration memo about the future of the space program. He says a big part of the problem is that, in more than four decades since the memo, the underlying question has not been adequately answered.

Logsdon pins much of the blame for the situation on President Nixon, who scaled back funding for NASA after the race to the Moon was won.

“The decisions he made from the ’69 through ’71 period, culminating in the January 5, 1972 announcement of the approval of the space shuttle, really characterized the program that NASA executed for the next 40-plus years, and basically avoided answering the question ‘What do we expect?’ by developing capabilities rather than seeking goals,” Logsdon said.

We had the answer under President Kennedy, according to Logsdon, when the goal was not just to put people on the Moon, but to achieve preeminence about all things in outer space.

“What is distinctive about Kennedy is he not only talked the talk, but he walked the walk,” Logsdon said. “He made a commitment of human and financial resources, peaceful but warlike mobilization of resources, to carry out that program of preeminence.”

Logsdon pointed out that the budget for NASA was $964 million when JFK urged the US to go the Moon; it had ballooned to $5.2 billion by 1965. Space science shared in the growth, its part of the NASA budget going from $131 million to $767 million in the same time frame.

Logsdon is tackling the history of presidential support for space exploration in his scholarship. He published John F. Kennedy and the Race to the Moon in 2010. His new book, After Apollo?: Richard Nixon and the American Space Program, is due out in March. The latter goes into great detail about Nixon’s approach and its lasting impact.

While NASA’s budget has fluctuated over the years, Logsdon sees a silver lining in the nation’s investment in science.

“The ups and downs in the overall NASA budget are not reflected in the budget for space science, which has shown a rather gradual but steady increase for the past 25 or 30 years, and has not vacillated,” he said. “Compared to the human spaceflight part of NASA, the space science, robotic science program, including Earth science, is in pretty good shape and is not being argued about.”

Logsdon served on the Columbia Accident Investigation Board, which opined in 2003 that NASA was being forced to do too much without adequate resources. He said that’s still a problem. The reason he doesn’t see a good solution ahead is that there are three possible responses, two of which he views as unlikely. He doesn’t foresee a great increase in our ambitions or some Sputnik-like incident that creates urgency about space. Nor does he anticipate a significant increase in spending, though that could depend in part on who the next president turns out to be.

“The most likely outcome is that we just keep muddling along, as we have since 1971, with a suboptimal program,” he concluded.

Further reading:


Shields up! Scientists find impenetrable barrier around Earth

Planet Earth has an invisible and impenetrable shield about 7,200 miles out in space that blocks killer electrons from coming in and zapping satellites and causing all sorts of other havoc in the wake of huge coronal mass ejections from the Sun. This barrier is a major discovery of the Radiation Belt Storm Probe and the Relativistic Electron Proton Telescope (REPT), launched by NASA in August of 2012.


Dr. Daniel Baker

Dr. Daniel Baker, REPT science lead at the Laboratory for Atmospheric and Space Physics at the University of Colorado, spoke about the mission and the discoveries today during his opening lecture at the 225th meeting of the American Astronomical Association in Seattle. The discoveries were detailed in an article in Nature back in November.

Baker has some great credentials for the project. He earned his Ph.D. under James Van Allen, whose gear first detected the Van Allen Belts—he preferred to call them zones—in 1957, in what many consider to be the first major scientific discovery of the space age. Baker also was an investigator on SAMPEX, a particle exploring mission that operated from 1992 until 2004.

There are twin REPT probes in a highly elliptical orbit around the Sun. One of the first major discoveries by REPT, according to Baker, was of a third Van Allen Belt, a storage belt of ultra-relativistic particles that remains constant while the other belts vary wildly because of solar events.

Interestingly enough, these particles don’t ever get in any closer than about 2.8 Earth radii. Baker says that was a strange discovery, as nature typically doesn’t like such sharp barriers, but observations so far have shown it to be an impenetrable.

“It looks, at least for the period of time, the couple of years, since the Van Allen probe launched that particles—ultrarelativistic electrons—can get in so far, they run into something almost like a glass wall, and can’t really get any further. This really was quite an interesting and fascinating puzzle.”

They looked into whether the phenomenon might be related to various actions of the Earth’s magnetic field, or even perhaps a reaction to radio waves broadcast from Earth, but those explanations fell short.

“We were left with the unsatisfying situation that very slow pitch-angle scattering and even slower radial diffusion can conspire to create this sharp gradient in the particle distributions,” Baker said. “To me, that’s not very satisfactory, but it seems to be the explanation.”

“I think its a subject now that our theoretical friends are struggling with and trying to understand and explain,” he added.

Baker says this new information is vitally important for those who may be studying x-rays from the Sun, synchrotron emissions from Jupiter, radio and x-ray emissions from distant nebulae, or extra-gallactic jets.

“All of these are visible because of energetic particles, electrons primarily, moving in strong magnetic fields,” he said. “Examining the details of how the accelerator that is so accessible to us in our own cosmic backyard can really give us much useful information about how acceleration processes work in these more removed systems.”

Baker says it is an exciting time in the field, with a great many instruments and missions collecting data.

“We have quite a golden age, in a sense, of measuring the properties of this entire magnetospheric system,” he said. “When we combine this information that we’re gathering now with the wonderful measurements of the Sun and the driving factors from the Sun, we really have the opportunity to make immense progress and to address the key questions that Van Allen and co-workers uncovered nearly 60 years ago.”

“The results from the Van Allen probes mission have in a real sense been rewriting the textbooks on many aspects of structure, acceleration, transport, and loss,” Baker concluded. “They’re giving us previously undreamt of capabilities.”