Tag Archives: Andy Connolly

Our favorite Seattle astronomy events from 2015

Happy New Year from Seattle Astronomy! Yesterday we ran down our top five news stories of the past year. Today, let’s take a look back at our top talks and events from 2015.

Comet Hunter

Scheiderer and MachholzRenowned comet hunter Don Machholz was the keynote speaker last year at the annual banquet of the Seattle Astronomical Society. Machholz has discovered eleven comets visually, without the aid of CCD cameras and other modern aids, and that’s the record. He does it the old-fashioned way, sitting at the eyepiece for hours at a time and sweeping the sky for something that wasn’t there before.

Machholz told a wonderful tale about his techniques of comet hunting and about the intensely personal reasons that drove him to the quest. It was an informative, touching, and often hilarious presentation filled with images and music.

It’s all relative

Jeffrey Bennett at the UW's physics/astronomy auditorium. Photo: Greg Scheiderer.

Last year was the international year of light and marked the 100th anniversary of the publication of Einstein’s theory of relativity. Jeffrey Bennett toured the country to help us better understand relativity, and stopped in at the April meeting of the Seattle Astronomical Society to give a well-received talk about the concepts of relativity. Bennett is an engaging lecturer and his book, What Is Relativity?: An Intuitive Introduction to Einstein’s Ideas, and Why They Matter, (Columbia University Press, 2014) is a big help, too, that makes a topic that is so mind-bending and daunting to so many truly accessible to a broader audience.

We did a preview interview with Bennett as well.

Physics pioneer

Jim Peebles

Science is mostly about brainpower and creativity, and testing, but there’s some luck involved, too. Case in point: back in 1965 Jim Peebles and colleagues at Princeton were on the hunt for what we now know as the cosmic microwave background, the lasting signature of the Big Bang. Up the road at Bell Telephone Labs, Bob Wilson and Arno Penzias had found the CMB, but didn’t realize what they had! To the latter went the Nobel Prize, but Peebles has been in the forefront of research on the CMB for the past 50 years. We now know a lot about the history of our universe, except for the first fleeting moments that remain a mystery. Peebles talked about that history at a UW lecture in May.

Space tourist

SimonyiCharles Simonyi shelled out a lot of cash to fly to the International Space Station in a Soyuz capsule with the Russians—speculation is that his tab for two trips, in 2007 and 2009, came to about $60 million. Simonyi gave a talk at the University of Washington in September about the practicalities of space travel, and when it might be possible for those of us with somewhat lesser means.

The answer, sadly, is not that soon, but Simonyi envisions a day when the cost of launching a kilogram of mass into space might be driven down to $100, and that might make the cost of space travel something that more people could consider.

Simonyi’s story was an entertaining one that was as much about the training for his two trips to space as it was about the technical aspects of getting there.

Dark matter and the dinosaurs

Lisa RandallHarvard particle physicist and author Lisa Randall has a new hypothesis about what may have killed the dinosaurs on Earth. It’s a surprisingly simple notion, at least once you get past the fact that it depends on a new sort of particle that we haven’t yet detected.

Randall spoke at Town Hall Seattle in November about her ideas and her new book, Dark Matter and the Dinosaurs: The Astounding Interconnectedness of the Universe (Ecco, 2015). The theory in a nutshell: suppose that there’s a type of dark matter that interacts with light. Such dark matter could collapse into a disk, just like our galaxy. As our solar system orbits the galaxy, we periodically go up and down through the galactic plane. Passing through the plane would also move us through this disk of dark matter, which could gravitationally dislodge comets from the Oort Cloud and send them hurtling our way.

It is an interesting idea that Randall says she’ll devote much time to testing in the coming years.

Honorable mention on our list: the lecturers of the Big Bang and Beyond series at the UW, including Andy Connolly, Miguel Morales, Julianne Dalcanton, and Adam Frank; George Musser, who spoke about his book Spooky Action at a Distance: The Phenomenon That Reimagines Space and Time–and What It Means for Black Holes, the Big Bang, and Theories of Everything (Scientific American / Farrar, Straus and Giroux, 2015); and Curiosity rover chief engineer Rob Manning, who gave a talk based on his tome Mars Rover Curiosity: An Inside Account from Curiosity’s Chief Engineer (Smithsonian Books, 2014).

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Weighing the universe

Astronomers are about to take their best shot at weighing the universe. You might well ask how and why; University of Washington astronomy professor Andy Connolly recently tackled those questions in a lecture titled “Unraveling Our Own Cosmic History.” The talk was the first in a series dubbed The Big Bang and Beyond being sponsored by the UW Alumni Association as part of the celebration of the 50th anniversary of the university’s Department of Astronomy.

Connolly

Professor Andy Connolly spoke Oct. 21 to kick off the Big Bang and Beyond lecture series celebrating the 25th anniversary of the Department of Astronomy at the University of Washington. Photo: Greg Scheiderer.

The why is easy: to try to figure out dark matter and dark energy. The how, according to Connolly, is actually pretty simple, too: they’re going to weigh the universe by looking at it, and not in a carnival weight-guesser sort of way.

To explain the idea, Connolly used an example of a swimming pool with tiles on its bottom. Water refracts light, and as the surface of the water in the pool ripples the reflections of light on the bottom of the pool move. Similarly, if you watch the grid of tiles on the bottom of the pool, the view will change. Connolly noted that by taking precise measurements of the distortion, we could determine the size of the waves and the mass of the water in the pool. Blow that model up to astronomical scale, about six billion light years, and you can weigh the universe.

Connolly looked, and found no grid in the sky, but notes that there are galaxies everywhere which can serve the same purpose.

“If I can measure the shapes of galaxies, and measure how they’re distorted through gravitational lensing, in the same way that I could measure the mass of the waves on the surface of a pool, I can now measure the mass of the universe,” Connolly said. “More importantly, I can measure that structure as a function of the age of the universe.”

The challenge is that while the structures are huge, they’re also spread out and the distortion will be miniscule. Spotting it will take a better telescope, and that’s one of the research reasons that the Large Synoptic Survey Telescope (LSST) is under construction in Chile. The UW is a founding partner of the LSST, which will have an 8.4-meter mirror and a 3.2 billion pixel camera. Its images will cover 3.5 degrees of sky; the Hubble Space Telescope would have to shoot about 3,000 images to achieve the same results.

“This means that (the LSST) can survey half the sky every three nights,” Connolly said. By comparison, it took the wildly successful Sloan Digital Sky Survey ten years to image a fifth of the sky. In other words, we’re in for a big download of data. Connolly said that the LSST will produce a thousand times more data than did Sloan, which revolutionized astronomy by making so much data publicly available.

The possible discoveries from so much new data are staggering. Connolly noted that data on a mere handful supernovae led to the discovery of dark energy.

“It’s amazing that measuring the distances and the brightness of 42 supernovae could reveal a component of our universe that drives the expansion, a component of our universe that makes up 73 percent of the energy budget in the universe today,” Connolly said.

“With the LSST, in ten years we’ll have 1.2 million supernovae,” he added. “A few tens of thousands of galaxies led to the discovery of dark matter through gravitational lensing. With the LSST we get four billion galaxies.”

If it all works, Connolly said it would help us solve what it perhaps the greatest scientific riddle of our time.

“If we can understand dark energy, if we can understand dark matter, if we can understand how the universe formed in the earliest fractions of a second, then we may be able to unify two of the biggest discoveries in the last hundred years: the discovery of general relativity, which explains gravity and how structure forms; and quantum mechanics, how our universe might have come into being.”

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