Category Archives: lectures

Major changes in store at Goldendale Observatory

Big changes are in store at the Goldendale Observatory in Goldendale, Washington. The facility’s telescope, installed in 1973, has already been reconfigured and more improvements are planned. Most of the existing facility, save for the south dome that houses the telescope, will be demolished this winter and replaced with a bigger, more useful observatory that operators hope will be operational in time for the solar eclipse in August.

Troy Carpenter

Troy Carpenter, interpretive specialist at Goldendale Observatory State Park, spoke at a recent Rose City Astronomers meeting about plans for improvements at the observatory. Photo: Greg Scheiderer.

Troy Carpenter, interpretive specialist at the observatory, talked about the plans at the recent meeting of the Rose City Astronomers in Portland. He said that up until recently the telescope and facility had been virtually unchanged since they opened.

The telescope, originally a 24.5-inch classical Cassegrain built by amateur astronomers from Vancouver, Washington, was reconfigured this summer.

“It is still the same telescope, but it has become a Newtonian,” Carpenter said. “The primary reason this was converted from Cassegrain to Newtonian is because, frankly, a classical Cassegrain telescope is totally inappropriate in Goldendale, Washington.”

The original scope, with an effective focal ratio of f/14.5, had a focal length of more than 9,000 millimeters. For telescopes and cameras, that’s extremely long.

“I would even say excessively long because it means the telescope can only operate at very high orders of magnification,” Carpenter said. That was bad, because the telescope couldn’t really look at large, dim objects like the Andromeda galaxy or Orion nebula. Also the scope required good seeing conditions, and while it’s dark and clear in Goldendale, the seeing at the observatory isn’t typically great. On top of that, the secondary mirror was eight inches wide with a ten-inch baffle that blocked too much light, leading to poor contrast at the eyepiece.

“In short, what we had was a horribly over-magnified image with terrible contrast all the time, and as a result this very impressive-looking telescope became kind of infamous, and not so much famous, for being awful,” Carpenter said. “All of these issues contributed to the decision to convert it to a Newtonian.”

That work, and some other adjustments to the telescope, its mount, and adjustability, were completed in September. Back to a more appropriate 3,050-millimeter focal length, Carpenter said views through the telescope are much better now. An improvement yet to come is replacement of the primary mirror, which has deteriorated over 43 years of use. In addition, the mirror is five inches thick, weighs 200 pounds, and takes four hours to reach thermal equilibrium, which is essential to good viewing.

A replacement is being fashioned by a company in Pennsylvania that has done work for NASA. The new mirror, computer designed and fabricated from inexpensive materials, will be the same width but just two inches thick and will weigh only 35 pounds. It will take just 15 minutes to cool to ambient temperature. They hope to have it in Goldendale and installed within the next few months. Its price tag, with a generous educational discount, is $25,000, and while that may sound like a lot, Carpenter noted a similar-sized mirror made of fused quartz might go for ten times as much, a quarter million.

New observatory

Big changes are in store for the buildings at Goldendale Observatory State Park, too.

Observatory plans

Preliminary plans for the new facility at Goldendale Observatory.

“We’re tearing it down so that a much larger facility can be built in its place,” Carpenter said. Everything except the south dome that houses the telescope will go. The new facility will include a large auditorium for classes and lectures that will seat about 150, interpretive exhibit space, and a rooftop observation deck. The total cost of the improvements, which are being made in several phases, is $5 million, which is being covered by capital funds appropriated by the Washington State Legislature. Demolition is set for this winter and they hope to be operational with the new facility in time for the total solar eclipse on August 21, 2017. While Goldendale won’t be within the path of totality as it was for the 1979 eclipse, the Sun will be about 98 percent obscured at the observatory that day, so it will still be something to look at.

One page detailing the planned improvements is above; you can see more of them in the latest newsletter from Friends of Goldendale Observatory.

Light pollution

While it’s pretty dark in Goldendale, many feel that light pollution has increased in town in recent years. Concerned folks this summer held a Gorge Night Sky Symposium to discuss the situation. (See our recap of the event.) Carpenter raised a few eyebrows in the room, mine included, with his take on the issue.

Goldendale Observatory

Goldendale Observatory. Everything but the dome on the right will be demolished to make way for improved facilities. Photo: Greg Scheiderer.

“I’m going to surprise you by not being the loudest opponent of the light pollution we have in Goldendale,” he said. He added that he grew up in New York and has lived in Philadelphia, so he knows light pollution.

“I’ve been to places where stars don’t exist,” he said. So while Goldendale has some light pollution, Carpenter noted that they still have great views of lots of faint fuzzies in the dark night sky.

“It’s low on my priority list because it’s a politically charged issue and it makes us very unpopular every time we bring it up,” Carpenter explained. “Our friends group, however, does care very much about light pollution and they do work hard.”

He noted that the town of Goldendale is working on an improved lighting code, and is converting to full cut-off, dimmable LED street light fixtures. Despite some light pollution, Carpenter said it’s still a great place for stargazing.

“You can see the Milky Way from horizon to horizon in Goldendale,” he said, “and that’s a wonderful thing.”

We look forward to a dark, clear future at Goldendale Observatory.

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Authors pick Titan as solar system’s best place for human colony

Mars is and has long been a popular choice for human colonization should we want or need to leave Earth. But Amanda Hendrix and Charles Wohlforth say that if we’re going to go live somewhere else in the solar system, then Saturn’s moon Titan is the best choice.

Hendrix, a planetary scientist who works for the Planetary Science Institute, and Wohlforth, an award-winning science writer, have just come out with a book, Beyond Earth: Our Path to a New Home in the Planets (Pantheon, 2016). They talked about Titan and the book last week at Town Hall Seattle.

Why go?

“The topic really is not just getting to another planet, but living there and staying there self sufficiently forever,” Wohlforth said. The big question to answer, he noted, is why.

“We don’t, as human beings, normally do big expensive things for no reason at all,” Wohlforth said. “That led us to thinking about what would we want on another planet, or what we would be getting away from here on Earth, that would drive us to want to move to another planet.”

While humans have long had a case of wanderlust, Wohlforth said the reasons to colonize another planet go beyond that.

“Environment drives colonization; it has in the past, and we don’t always call it environment,” he said. “We call it overcrowding or we call it wealth seeking, but really in our society economics is how we talk about environment a lot of the time.”

A key to colonization, he said, is having the resources to do it and to keep it going.

“Making colonies requires technology and it also requires wealth and the ability to make money, and in our world that’s often meant that government gives private industry the money to get started,” Wohlforth said. “Colonies need a reason to exist environmentally or economically, they need major government investment to happen, and ultimately they need a way to support themselves without help from home.”

Why Titan

Hendrix said they developed five main criteria they considered when evaluating a place as a possible site for a human colony. It should have an atmosphere, a magnetosphere, manageable temperatures, a decent amount of gravity, and a hospitable landscape. Among those, she said the first two are most important, as the atmosphere and magnetosphere could shield colonists from harmful radiation.

Wohlforth and Hendrix

Charles Wohlforth and Amanda Hendrix talked about their new book “Beyond Earth” Nov. 18, 2016 at Town Hall Seattle. Photo: Greg Scheiderer.

It was easy to winnow the list. Venus was rejected out of hand as a super hot hellhole with a poisonous atmosphere that may well be volcanically active.

“It’s really not the greatest environment for a human settlement,” Hendrix understated, “but what’s interesting about Venus is that in that thick atmosphere there is an altitude at which air that we like to breathe is stable. You could, in theory, have a floating city of balloons that are filled with air and where humans could live.”

On Mercury, Mars, or the Moon people would likely have to live underground to avoid radiation. That’s not very appealing, either.

“It’s not really what we’re going for,” Hendrix said. “We’d like to find a place in the solar system, if possible, where we can live on the ground and have a decent amount of radiation shielding.”

Jupiter has a lot of interesting moons, but the king of planets churns out huge doses of radiation and is not a very hospitable place. When you get out to Saturn, though, Titan catches the eye.

“One of the number-one reasons is that it has an Earth-like atmosphere,” Hendrix said. It’s mostly nitrogen with some methane, and is at about 1.5 times the pressure of our atmosphere on Earth. Titan has no magnetosphere of its own, but for much of its orbit it lies inside Saturn’s magnetosphere, so they can share.

“We think that for our key points of shielding from radiation by either an atmosphere or a magnetosphere, Titan is a very good place,” Hendrix said. “This really sets Titan apart from the other places that we looked at in the solar system for a long-term human colony.”

More positive features

We know a lot about Titan through data gathered on 124 fly-bys of this moon by the Cassini spacecraft. Titan has a lot of Earth-like features. It has clouds, rain, swamps, wind, and sand dunes. It has surface liquid—lakes and seas of methane and ethane. (Water would freeze.) It’s cold there, but Titan has pretty constant temperatures across seasons and latitudes.

There’s also a virtually limitless energy source on Titan. Reactions between its atmosphere, sunlight, and energy from Saturn create hydrocarbons that cover the moon’s surface. Colonists could drill down and get water from Titan’s liquid subsurface ocean, separate out the hydrogen and oxygen, giving them the chemistry needed to burn the hydrocarbons.

“You can imagine settlers on Titan having a power plant that takes in methane and water, and the output is energy and breathable oxygen,” Hendrix said. “So it could work out quite well for our colonists—plenty of energy.”

Don’t pack your bags yet

Setting up a colony on Titan would not exactly be a piece of cake, especially if you didn’t survive the trip. NASA has compiled a long list of potential health risks for astronauts, many of them related to radiation exposure, and concluded that space flights of more than a year are too risky for humans. It would take seven years to get to Titan with current technology.

“These are risks that, without some technology leaps,” Wohlforth cautioned, “we’re not going to Saturn. We simply can’t get there and have the astronauts be safe.”

The key to the trip is finding a way to go faster. Wohlforth said the commercial space sector is making some headway on this, and a NASA scientist named Sonny White is actually working on a propulsion system that uses quantum virtual particles and is also tinkering with a warp drive. That notion drew applause from the Trekkies at the talk, but Wohlforth noted that there’s a pretty good dose of skepticism out there. While warp drive may be “poppycock” as one headline writer opined, it’s not unreasonable to think that some smart engineer is out there cooking up a way to make space ships really zip.

Challenges aside, the urge to go and explore and colonize is strong. Hendrix and Wohlforth touched briefly on a lot of topics that are covered in more depth in the book—such considerations as how society might develop elsewhere, how reproduction might change in a Titan colony, and other challenges and opportunities.

“We really like Titan as a potential human colony location,” Hendrix concluded. “We think it has a lot to offer.”


You can purchase Beyond Earth by clicking the title link or book cover image above. Buying through Seattle Astronomy supports our efforts to bring you interesting space and astronomy stories, and we thank you.

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Talk about Proxima b highlights week’s calendar

Thanksgiving week is a little light on astronomy events, but there are several club meetings and an interesting talk on the calendar.

Habitability at Proxima b

Victoria Meadows

Victoria Meadows. Photo: UW.

There has been a great deal of talk about exoplanet Proxima b since its discovery in orbit around our nearest stellar neighbor, Proxima Centauri, was announced this summer. The planet’s orbit is within the habitable zone of the star, but there’s still a great deal of question about how habitable planets can actually be when they orbit are close to M dwarf stars such as Proxima Centauri. Victoria Meadows, a professor of astronomy at the University of Washington and principal investigator for the NASA Astrobiology Institute’s Virtual Planetary Laboratory, will talk about how they’re modeling the Proxima system and prospects for observing this interesting exoplanet at 3 p.m. this Tuesday, November 22 during an astrobiology colloquium in Physics/Astronomy Auditorium 118 on the UW campus in Seattle.

If you can’t be there in person you can view the presentation via live stream.

Club events

Rose City AstronomersThe Rose City Astronomers will hold their monthly meeting at 7:30 p.m. Monday, November 21 at the Oregon Museum of Science and Industry in Portland. The guest speaker will be Troy Carpenter, administrator of the Goldendale Observatory State Park in Washington, who will talk about the limitations of human vision, how those limitations hinder our ability to observe the universe, and the technological solutions of the past century that allow us to transcend these challenges. Carpenter will also talk about the Goldendale Observatory upgrade project.

The Island County Astronomical Society will hold its monthly meeting at 6:30 p.m. Monday, November 21 at the Oak Harbor Library. No information about guest speakers or programming had been published as of this writing.

Ron Hobbs

Ron Hobbs. Photo: Greg Scheiderer.

The Eastside Astronomical Society will meet at 7 p.m. Tuesday, November 22 at the Lake Hills Library in Bellevue. Guest speaker Ron Hobbs, a NASA Solar System Ambassador, will talk about how amateur astronomers and other citizen scientists are contributing to space exploration by helping to process the deluge of imagery that comes down daily from space probes.

Futures file

You can scout out future astronomy events on our calendar. New additions to the calendar this week include:

Up in the sky

Jupiter will appear very close to the Moon on Thanksgiving day. This Week’s Sky at a Glance from Sky & Telescope magazine and The Sky This Week from Astronomy offer more observing highlights for the week.

Happy Thanksgiving!

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Asteroid spotting with NEOWISE

The solar system seems like a big place with lots of empty space in it, at least until an astronomer plays a simulation of the orbits of its asteroids. Such a simulation looks like an angry swarm of bees, and Earth appears likely to be stung by them several times per day.

Joe Masiero

Joe Masiero, a scientist with the NEOWISE project, spoke at the meeting of the Seattle Astronomical Society Nov. 16, 2016. Photo: Greg Scheiderer.

Some scientists at NASA’s Jet Propulsion Laboratory convinced the agency a few years ago to give them the keys to a hibernating but still semi-functional space telescope, and now the Near-Earth Object Wide-field Infrared Survey Explorer (NEOWISE) is on the hunt for asteroids and other near-Earth objects. Mission scientist Joe Masiero talked about NEOWISE at this week’s meeting of the Seattle Astronomical Society.

Masiero explained that NEOWISE is a part of NASA’s near earth object observation program.

“This is one of the funding lines that NASA has specifically dedicated to discovering and characterizing objects that come close to the Earth,” he explained. “It’s one of a number of missions and a number of telescopes that do these surveys for near-Earth objects trying to look out to see if anything is posing a hazard to our planet.”

Used scope for sale

That important work is being done by a hand-me-down space telescope. WISE launched in December of 2009 on a mission to essentially build an infrared atlas of stuff to help scientists decide where to point the James Webb Space Telescope when it becomes operational. WISE looked for the most luminous galaxies in the universe, close and cold brown dwarfs, and other sorts of objects for Webb to explore. That mission complete by the following September—and two of four infrared wavelength detectors shot because their coolant ran out—WISE was put into hibernation for almost three years. But the JPL team thought the 40-centimeter scope could still be used for science with the two infrared detectors that didn’t need cooling, and convinced NASA to resurrect WISE as NEOWISE. They fired the scope up again in December of 2013.

“The goals of the NEOWISE mission are to survey near-Earth objects,” Masiero explained, “both to discover new ones, but even more importantly, to characterize ones that we currently know about, to figure out how big they are and how reflective they are, because it’s the reflectivity, the albedo of an object, gives you an initial hint as to what it’s made of.”

There are a number of programs looking for near-Earth objects, such as PanSTARRS and the Catalina Sky Survey, but Masiero said NEOWISE brings something different to the table.

“One of the benefits of NEOWISE as an infrared survey is that we’re discovering a lot of these objects that are very dark—that look like a lump of coal—and sometimes that are very big,” he explained, adding that this is the mission’s special niche.

“There are other surveys finding more near-Earth objects than we are,” he said, “but what we excel at is finding these very dark objects that other telescopes miss.”

The mission has been prolific. Between WISE and NEOWISE, Masiero said they’ve discovered about a thousand near-Earth objects larger than a kilometer.

“Those are the dinosaur-killer level,” he said. In addition, they’ve found about 20,000 objects in the 100-meter class; the type that could cause a “bad day” were they to hit Earth.

Science, too

Possible mass extinction is reason enough to keep an eye out for near-Earth objects, but Masiero notes that there’s science to be done as well. Since these objects are close in they’re easier to study and visit, and there are a number of future missions planned to do just that. Asteroids could also give clues to the formation of the solar system.

Masiero’s particular interest is in looking at main-belt asteroids, which don’t get as much study because they’re so hard to see. One interesting thing they’ve been able to do with NEOWISE is to determine the albedo of asteroids. They’ve found that many objects with a matching albedo also share the same orbital inclination. These asteroid “families” traveling in clusters also often match in optical color.

“This is a single large object that something crashed into and shattered into hundreds or thousands of smaller pieces,” Masiero said. “Because it came from a single object, they all have a similar composition.”

These families are pretty new, geologically speaking. Masiero said that families that formed in the last billion years or so make up over a third of all the objects we know about in the main asteroid belt. NEOWISE data may help scientists track the families, learn what they’re made of, and how they evolved.

The next generation

NEOWISE is funded through next summer, and while they’re hoping to get an extension, eventually the satellite’s orbit will decay and it will burn up in the atmosphere. Masiero said they’re now proposing a new mission, called NEOcam. This would be similar to NEOWISE, except the telescope would be a bit bigger, with a 50-centimeter mirror, and they would fly it out to the first Lagrangian point—L1—where it would stay cold and work indefinitely.

NEOcam

NEOcam: NASA/JPL-Caltech

“If we’re selected we would fly this space telescope specifically designed to search for near-Earth asteroids in the infrared,” Masiero said. “The goal of this survey is to characterize these objects, quantify them, and help us predict what kind of hazard they could pose to the Earth.”

NEOcam could take longer exposures and thus look deeper into space and find more objects. He expects a five-year survey would find some 300,000 near-Earth objects and eight million main-belt asteroids—an increase of an order of magnitude for both.

“This would improve upon the census taken by NEOWISE, helping us characterize the hazard, but also—very interesting from a scientific point of view—figure out where these populations turn over, how many you have in each size band, and hopefully trace them back to where they come from,” Masiero said.

Citizen science

If you want to sift through the data on your own, it’s all available online. Masiero said it is all on the Infrared Science Archive (IRSA), where there are millions of images and only a few people to look at them. He said the Planetary Data System and NASA’s Horizons tool have also incorporated NEOWISE data.

Perhaps you will spot a killer asteroid or figure out how the solar system formed.

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Mapping the heavens with Priya Natarajan

Priyamvada Natarajan, a theoretical astrophysicist at Yale University, is excited to be working in physics and astronomy at a time she and others call the “golden age of cosmology.”

“The maturity of our theoretical understanding, the sophistication of our instruments and tools that allow us to get the data—spacecraft, detectors—and the advanced computing are all aligned at the moment,” Natarajan said this week during a talk at Town Hall Seattle.

Natarajan

Theoretical astrophysicist Priyamvada Natarajan spoke Nov. 14, 2016 at Town Hall Seattle.

Natarajan has done a lot of work on mapping dark matter and dark energy, on gravitational lensing, and on figuring out how supermassive black holes are formed. It’s the latter that has her excited for the launch of the James Webb Space Telescope. She’s been a leader in pushing the idea that supermassive black holes could be formed by the direct collapse of matter. The physics pencils out, and Webb will peer back and possibly find the most distant, and therefore the first, black holes, and perhaps validate her ideas.

“The fact that you can come up with an idea as a scientist, for me, that’s the privilege,” she said.

Natarajan is the author of Mapping the Heavens: The Radical Scientific Ideas That Reveal the Cosmos (Yale University Press, 2016). She said she wrote the book not only to help us understand new discoveries about black holes and dark matter, but also to demystify the process of science.

“I believe very strongly that the current rampant disbelief in science stems from the contingent nature, the provisionality of science.” Natarajan said. “It’s something that’s very hard for the public at large to understand.”

The plus side is that cosmology and astronomy have the potential to win converts.

“Unlike many other fields in science, the night sky belongs to all of us,” she said. “We have to just look up and it’s there; the glory and the awe of the night sky.”

We know a lot

Natarajan finds it interesting that we know so much about the universe, with pretty solid evidence for much of what has happened since the tiniest fraction of a second after the Big Bang.

“It still stuns me that with a cantaloupe-sized gelatinous thing in our skull we’ve been able to figure all of this out,” she laughed. Yet despite all we do know, she said there is still a lot of mystery about our peculiar universe.

“We happen to live in one in which the total energy content of the universe is dominated by two components that we don’t know what they are,” she said.

Matter graph

Chart: NASA

What we call them are dark matter, which makes up 24 percent of the universe, and dark energy, which makes up 71 percent. We and all the stuff we see are less than five percent. Though we don’t know what dark matter is, Natarajan said there is solid evidence that it is indeed out there.

“The idea came out of an empirical need to explain an observation,” she said. Oddly enough, one of her other research interests, black holes, were conceived in exactly the opposite fashion.

“Black holes were actually proposed as a mathematical entity,” she noted. “They were a mathematical solution to Einstein’s equations, and they eventually became real.”

A little history

Dark matter was first suggested by Fritz Zwicky in 1933. Vera Rubin and others looking at galaxies in the 1970s proposed it as the reason rapidly spinning galaxies don’t fly apart. Natarajan said more than 80 years of research has left little doubt.

“We have incontrovertible evidence from many independent lines of investigation for the existence of dark matter because of the effects it produces, although it has not been directly detected yet,” she said. “We don’t know the particle.”

There are two lines of evidence, according to Natarajan, that make dark matter far more than just an inference.

“We can exquisitely map it at the moment, even though we can’t see it, because of the gravitational influence that it exerts,” she said. “The other way in which we can detect dark matter is the impact that matter has on the propagation of light in our universe.”

This is where her work on gravitational lensing fits in. Large galaxy clusters, with as many as a thousand galaxies, can act as a sort of gravitational lens on steroids. Such clusters would be held together by enormous amounts of dark matter. The relativity “pothole” created by the cluster could be strong enough to split a beam of light.

“You end up seeing multiple images of an object where in reality there is only one object,” Natarajan said, noting that this has been observed many times now. Interestingly, she points out that the physics of both Newton and of Einstein would predict the effect.

“You can apply both of these arguments to clusters and you infer the same amount of dark matter,” she said. “In my opinion that is really, really strong evidence, compelling evidence, because they’re completely different world views and they still converge. There’s no escaping the concept of dark matter.”

Search for the holy grail

Natarajan said this sort of research may help us get to the holy grail of physics: a quantum theory of gravity.

“The motivation is to look for gaps, look for disagreements, and look for anomalies where an observation is actually inconsistent with our theoretical expectation,” she said.

A couple of great examples of this came out of the 1800s. The orbit of Uranus didn’t agree with Newton’s Laws, so they did the math and figured another planet could cause the observed discrepancies. That led to the discovery of Neptune. At the same time, there were anomalies in Mercury’s orbit, which led to the proposal that another planet, called Vulcan, was the cause. Vulcan was never found, but years later general relativity explained the precession of Mercury’s orbit perfectly.

“In one case the theory remained intact and an anomaly refined our understanding,” Natarajan said. “In the other case it pointed the way to the existence of a more fundamental covering theory that was yet to come.”

We can’t wait for the next breakthroughs in this golden age of cosmology.


You can purchase Mapping the Heavens by clicking the book cover or title link above. Buying through Seattle Astronomy helps defray our costs of creating and serving these articles. Thank you!

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NEOWISE, Viking, and more on the calendar this week

The Seattle Astronomy calendar is packed with interesting events this week, with something going on just about every evening. Seattle gets two talks about NEOWISE, the Mars program premieres on the National Geographic Channel, and there are several other lectures of note.

NEOWISE

NEOWISEWill an asteroid or comet one day smack into Earth again? One of the sets of eyeballs looking for Near Earth Objects (NEOs) is the Wide-field Infrared Survey Explorer (WISE). Joe Masiero, a JPL scientist with NEOWISE, will give two talks about the project this week in Seattle. He’ll speak at the monthly meeting of the Seattle Astronomical Society at 7:30 p.m. Wednesday, November 16 in the Physics/Astronomy Auditorium on the University of Washington campus. Masiero will return to the same room at 4 p.m. Thursday, November 17 for a presentation at the weekly UW astronomy colloquium. He will give an overview of the NEOWISE mission, and present some results from the latest dataset release.

Mapping the heavens

The cosmos, once viewed as stagnant, even ordinary, is now understood to be a fathomless universe, expanding at an accelerating pace, propelled by dark energy, and structured by dark matter. Theoretical astrophysicist Priyamvada Natarajan, author of Mapping the Heavens: The Radical Scientific Ideas That Reveal the Cosmos (Yale University Press, 2016), will give a talk about these ideas at 7:30 p.m. Monday, November 14 at Town Hall Seattle. Natarajan will explain the science behind some of the most puzzling cosmological topics of our time and discuss why there is so much disagreement within the science community about astronomical discoveries.

Tickets are $5 and are available online.

Preserving Viking

VMMEPPThe final of three Science Pub events about the Viking missions will be held at 6 p.m. Monday, November 14 at the Old World Deli in Corvallis, Oregon. Rachel Tillman, Founder and Executive Director of The Viking Mars Missions Education & Preservation Project, and others involved in the missions, will talk about Viking and its influence on technology and culture. The Science Pub is a program of the Oregon Museum of Science and Industry. It’s free!

If you are not able to attend this event and missed the previous ones in Portland and Eugene, fear not; Seattle Astronomy is working on a feature article about The Viking Mars Missions Education & Preservation Project. Stay tuned!

Eugene Astro

The Eugene Astronomical Society will hold its monthly meeting at 7 p.m. Thursday, November 17 at the Science Factory planetarium. The club’s mirror-grinding group will give a presentation about how reflecting telescopes’ primary mirrors are made, complete with demonstrations of the grinding process.

Cosmos on Tap

Astronomy on Tap Seattle, November 2016This month’s Astronomy on Tap Seattle event will be held at 7 p.m. Wednesday, November 16 at Peddler Brewing Company in Ballard. They’ll view episode five of the original Carl Sagan Cosmos series, complete with Cosmos bingo, trivia contests, prizes, and beer. Astronomers will discuss what’s changed, and what science has held up, since the series first aired.

Astronomy on Tap Seattle is organized by graduate students in astronomy at the University of Washington.

A home in the stars

Want to live on Mars? Maybe a bad idea. Planetary scientist Amanda Hendrix and science writer Charles Wohlforth have looked into space colonization, and suggest that Saturn’s moon Titan might be a better place. The authors of Beyond Earth: Our Path to a New Home in the Planets (Pantheon, 2016) will discuss their findings at 7:30 p.m. Friday, November 18 at Town Hall Seattle. Why Titan? It has a nitrogen atmosphere, a weather cycle, and an inexhaustible supply of cheap energy. Get the full story from Hendrix and Wohlforth; grab the book in advance.

Tickets are $5 and are available online.

Mars

MARS showOK, some may want to give Mars a shot! The television mini-series Mars premieres at 9 p.m. Monday, November 14 on the National Geographic Channel (although an online stream of the opening episode has been available online for several weeks now.) Part feature film, part documentary, the series takes a look at what a Mars mission might look like in 2033, and talks with today’s experts about the development of technology and capabilities that could make such a mission a reality. Ron Howard is an executive producer of the series, which has been directed by Everardo Gout.

TAS

The Tacoma Astronomical Society plans one of its free public nights for 7:30 p.m. Saturday, November 19 at the Fort Steilacoom campus of Pierce College. The all-weather presentation will be about the New Horizons mission to Pluto and beyond. If the skies are clear club astronomers will break out the telescopes for some observing.

Up in the sky

There’s a “supermoon” on Monday and the Leonid meteor shower peaks this week. This Week’s Sky at a Glance from Sky & Telescope magazine and The Sky This Week from Astronomy offer more observing highlights for the week.

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LSST: mining the sky in 4D

The Large Synoptic Survey Telescope (LSST) is going to be a unique astronomical instrument.

“Unlike a lot of other telescopes around the world, LSST is actually aptly named,” joked Dr. David Reiss of the University of Washington at a recent gathering of Astronomy on Tap Seattle at Peddler Brewing Company in Ballard. Reiss and Dr. John Parejko, two UW astronomers involved in the project, gave an overview of the telescope, which is under construction in Chile.

Parejko and Reiss

John Parejko (left) and David Reiss, research scientists at the University of Washington, discussed the Large Synoptic Survey Telescope at an Astronomy on Tap Seattle event October 28 at Peddler Brewing Company in Ballard. Photo: Greg Scheiderer.

As for the name, Parejko noted the scope will be truly large. It will have an 8.4-meter mirror, a 3.2-gigapixel camera, and will take an image of the night sky every 30 seconds.

“We’re going to generate 15 terabytes of data every single night,” Parejko noted. “That means by the end of the survey we’ll have 30 trillion database entries, and over half an exabyte of data and images being catalogued.”

“That’s a lot of data even for those of you who work at Amazon,” he quipped.

Synoptic is the word even the scientists say they have to look up every time. Essentially it means that the instrument will look at everything as a whole and provide a synopsis.

“Unlike a lot of other telescopes, the LSST has been designed to serve thousands of astronomers with interests ranging from supernovae or exploding stars, to planets and asterois, to the universe as a whole,” Reiss explained.

It’s a survey because LSST will not look at just one object.

“Not only is it covering all kids of different science, it’s actually covering the whole sky,” Parejko said. They hope to start observing in 2022, and the 10-year survey will photograph the entire sky every three nights. They expect to discover 37 billion stars and galaxies.

Lastly, it’s a telescope, but it’s much more.

“The main thing that LSST is going to produce is lots and lots of data,” Reiss said, “images and catalogs and databases of all of the objects in the sky that are going to be shared with everybody in real time.” With new information coming in constantly, they’ll be effectively creating a 10-year, multi-color, ultra high-resolution movie of the night sky.

The building

Parejko described the facility, which is being built on the Cerro Pachón ridge at 8,700 feet elevation, not far from town of La Serena in the mountain desert of Chile. It’s a good site for an observatory, with high elevation and low humidity. The building has been designed with a lab for working on the mirror and other parts of the telescope so that they don’t have to send things off the mountain for repairs.

“That means we minimize our down time; we can spend as much time as possible taking data,” Parejko said. You can watch progress of the construction on the LSST webcam.

LSST

An artists’ concept of the Large Synoptic Survey Telescope. Image: LSST.

The telescope itself will be short, squat, and compact, with the secondary mirror and camera located out at the end. They’re building it short to reduce wobble when it moves—another measure for minimizing down time. They were able to keep it short by using a different shape on the outside of the primary mirror than on the inside. Light will come into the scope, reflect off the outside of the primary to the secondary mirror, back down to the inside of the primary, which will beam it up to the camera.

“That’s how we can keep the telescope so short and compact, by folding the light like that,” Parejko explained.

The camera, about the size of a Smart Car, will have three lenses and space for five filters. The detector will feature 21 “rafts” each with nine CCDs. If one raft breaks, they’ll just pull it out, plug in another, and keep imaging.

The building will also include a major computer lab. That’s still under design.

LSST software

Reiss explained that, with so much data being collected, computing will be important. Essentially, they’re building, “sort of a Google index of the entire night sky over the course of ten years.” To do that, they’re creating a high-speed network to connect the telescope in Chile to a supercomputing center in Illinois. There, they’ll look for things that move or blow up, and expect to spot some 10 million events every night. Information about these discoveries will go out in nightly alerts to interested users.

“We’re basically providing the equivalent of astronomical Twitter, Google, and Amazon Web Services to the community,” Reiss said.

“We’re going to be sending out nearly 600 gigabytes worth of simply just these alerts every night,” he added. “If one of you were going to subscribe to these you’re going to max out your Comcast monthly allocation in one night.”

Researchers will be able to upload their software or algorithms into the LSST computing cluster and do calculations in the cloud, rather than having to download all of that data. Many institutions will receive the alerts and write algorithms that will help users pick and choose data. There will likely be smartphone apps that will allow users to, say, track their favorite asteroid, and people will be able to use the data to learn about the universe or do citizen science. Reiss noted that, by keeping a constant eye on the sky, we will be able to spot lots of the sorts of things that we only find today through the luck of looking in the right place at the right time.

LSST goals

The main science goals of the LSST are to learn about dark matter and dark energy, catalog the solar system, watch how things change, and learn about the structure and formation of the Milky Way.

Astronomy on Tap Seattle, November 2016The LSST team includes 39 institutional members, among them 21 colleges and universities. The UW is a founding member. The project employs 200 astronomers and engineers from 19 different countries. The total cost of getting LSST up and running by 2022 will be about $400 million. That sounds like a lot of money, but Reiss and Parejko pointed out, given the season, that it’s about what Americans spend on Halloween costumes for their pets in a typical year. Funding for the project has come from the National Science Foundation, the U.S. Department of Energy, and through fundraising by the nonprofit LSST Corporation.

Astronomy on Tap Seattle is organized by graduate students in astronomy at the University of Washington. The events are free, but you can help them cover the costs of creating them by donating online to the Friends of Astronomy Fund at the UW. The next event is scheduled for 7 p.m. Wednesday, November 16 at Peddler, and will be a Cosmos on Tap. Attendees will watch an episode of the original Carl Sagan series, and scientists will give updates on how the science has changed since the show first aired. As always, there will be trivia contests, and beer.

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