Category Archives: lectures

SpaceFest at MOF tops week’s astro calendar

A three-day space fest, several star parties, some astronomy club meetings, and a chance to meet Viking mission folks are on tab for the next week of astronomy events.

SpaceFest: Ladies who LaunchThe third annual SpaceFest at the Museum of Flight kicks off Thursday for three days of exhibits and presentations. Under the theme of Ladies Who Launch, this year’s SpaceFest celebrates women astronauts, engineers, authors, and others who helped put America into space.

The days are packed with events. Highlights include a talk by South Korean Astronaut Soyeon Yi at 1 p.m. Friday, November 4, and a keynote at 2:15 p.m. Saturday, November 5 by Nathalia Holt, author of Rise of the Rocket Girls: The Women Who Propelled Us, from Missiles to the Moon to Mars (Little, Brown and Company, 2016). The book is a tale of young women who, with only pencil, paper, and mathematical prowess, transformed rocket design, helped bring about the first American satellites, and made the exploration of the solar system possible.

You can order the book by clicking the link above; purchases through the Seattle Astronomy Store help defray our operating costs and enable us to bring you great astronomy stories. Check the full schedule for the weekend on the museum’s online calendar. We plan to attend a number of the sessions, and will report back!

Viking at Portland Science Pub

VMMEPPMeet some of the folks involved with the Viking Mars missions in the mid-1970s at Science Pub Portland at 7 p.m. Thursday, November 3 at McMenamins Mission Theater in Portland. As an 11-year-old girl Rachel Tillman saved the last remaining un-flown Viking spacecraft from the scrap heap. She later became founder and is executive director of the nonprofit organization The Viking Mars Missions Education & Preservation Project. Tillman will speak at Science Pub Portland, along with Al Treder, who worked on Viking guidance and control; Pat DeMartine, Viking lander command sequence and simulation programmer and science team member; and Peggy Newcomb, wife of NASA Viking engineer and author John Newcomb, who passed away in March.

Suggested donation for admission is $5. Science Pub Portland is a program of the Oregon Museum of Science and Industry. If you can’t make this Viking Mars Mission event, it will be repeated at Science Pub Eugene on November 10 and Science Pub Corvallis on the 14th.

Saving the planet

Ed Lu

Ed Lu. Photo: NASA

When the Large Synoptic Survey Telescope comes online, it is expected that the discovery rate of near-Earth asteroids will increase by more than a factor of 20 over the current rate, and that the list of asteroids with a worrisome probability of hitting the Earth will also become much larger. Astronaut Ed Lu, CEO and co-founder of the B612 Foundation, will discuss the scientific as well as public policy challenges related to potential asteroid impact scenarios at this week’s University of Washington astronomy colloquium. The event will be held at 4 p.m. Thursday, November 3 in the Physics/Astronomy Auditorium on the UW campus in Seattle.

Club meetings

The Tacoma Astronomical Society will hold its monthly meeting at 7:30 p.m. Tuesday, November 1 in room 175 of Thompson Hall on the University of Puget Sound campus in Tacoma. Topics will include a review of some of the club’s new gear and a primer on Proxima b, a roughly Earth-sized planet believed to be in orbit around our nearest stellar neighbor.

The Spokane Astronomical Society will hold its monthly meeting at 7:30 p.m. Friday, November 4 at the planetarium at Spokane Falls Community College. Specific topics or guest speakers for the gathering had not been published as of this writing.

Star parties

There are three star parties on the calendar for this week. The Covington Community Park Star Party is planned for 8 p.m. Friday, November 4 at the park. The event is a joint effort of the Seattle Astronomical Society and the Boeing Employees’ Astronomical Society.

The Seattle club also plans its free monthly public star parties for 6 p.m. Saturday, November 5 at two locations: Green Lake in Seattle and Paramount Park in Shoreline. Cloudy weather will mean cancellation of the star parties; watch the club’s website or social media for updates.

Tacoma Astronomical Society will hold one of its free public nights at 7:30 p.m. Saturday, November 5 at the Fort Steilacoom campus of Pierce College. The indoor program will be about spectroscopy. If the weather is clear they’ll break out the telescopes and have a look at what’s up in the night sky.

Futures file

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

Up in the sky

The Taurid meteor shower peaks this Thursday and Friday. This Week’s Sky at a Glance from Sky & Telescope magazine and The Sky This Week from Astronomy have more observing highlights for the week.

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LIGO founder Rainer Weiss talks gravitational waves at UW

There has been a great deal of talk about gravitational waves since scientists with the Laser Interferometer Gravitational-Wave Observatory (LIGO) announced back in February that they had collected the first evidence of the phenomenon in September 2015. Dr. Rainer Weiss, professor emeritus of physics at MIT and one of the founders of LIGO, talked about the history, discovery, and future of LIGO Tuesday at the University of Washington. The event was part of the Frontiers of Physics lecture series of the University’s College of Arts and Sciences.

Was LIGO really the first?

Rainer Weiss at UW

Dr. Rainer Weiss, a co-founder of LIGO, gave a lecture this week at the University of Washington about the detection of gravitational waves. The logos represent the more than 80 organizations involved in the LIGO Scientific Collaboration. Photo: Greg Scheiderer.

Weiss said that it might not be totally accurate to say that LIGO was the first to spot gravitational waves. Joseph Weber at the University of Maryland claimed to have detected them way back in 1969, but no other scientists could duplicate his observation, and the claim was eventually discredited. Weiss said much credit should go to Russell Hulse and Joseph Taylor, Jr., of the University of Massachusetts. They used a radio telescope to study what is now called the Hulse–Taylor binary, and noticed that the orbits of these two neutron stars around each other have decayed since they were discovered in 1973. A graph of the decay matches up precisely with a plot of the loss of energy predicted due to gravitational waves.

“It’s a dead ringer,” Weiss said. “That was, as far as I’m concerned, the first real evidence that there were gravitational waves. It was a very important moment, because there had been endless discussions in the scientific community about whether the gravitational waves that Einstein had predicted were real or not.”

In a way the detection of gravitational waves is like the story of an “overnight sensation” who hits the big-time after decades toiling in obscurity. The first glimmerings of LIGO go back more than 40 years, and the basic design of the observatory was actually created well before Einstein dreamed up gravitational waves as part of the general theory of relativity.

The beginnings of LIGO

Back in 1967 MIT asked Weiss to teach a course about relativity. He didn’t tell them that he wasn’t really up on the math of relativity, and joked that it was all he could do to keep a day ahead of his students. Weber was doing his experiments at the time, and Weiss had his class do a thought experiment—what Einstein would call a Gendankenexperiment—about how to detect gravitational waves using light beams. Their solution was essentially a Michaelson Interferometer, a device developed in 1880s. (An animated view of a simple interferometer is below; also check our recent post about LIGO from an Astronomy on Tap Seattle event.) A few years later, after the Weber findings were dismissed, Weiss started to think about the detection of gravitational waves a little more seriously.

“I wanted to convert that Gedankenexperiment into a real apparatus,” he said.

An animation of how LIGO works. A laser beam is directed through a splitter into two
equal-length arms, and reflected back. If the length remains the same, the reflected beams
cancel each other out. But if a gravitational wave distorts the beams, they do not cancel and
light reaches a detector. Image credit: LIGO/T. Pyle.

This was easier said than done. As noted, many in the scientific community doubted that gravitational waves existed, and even Einstein had expressed doubt that they could ever be detected. This made getting funding for the work a challenge. The technical obstacles were greater still. The device had to detect preposterously small distortions in spacetime—along the order of a thousandth of the width of a proton—and it had to do so in an environment in which there is a tremendous amount of noise. The Earth itself is spinning and vibrating, ocean waves lap up on the shore, a train goes by. They had to figure out a way to get the interferometer mirrors to hold still. That problem was solved by suspending the mirrors from multiple pendula, which themselves hang from a noise-reducing feedback system. Even a little heat or a molecule of oxygen in the interferometer tube could distort the light beam.

“The way you get rid of it: you make a very good vacuum, and that costs a lot of money,” Weiss noted. They also added mirrors to the basic design that make the light path longer and keep more light in the system, both ways to amp up the sensitivity of the instrument.

It’s no wonder this “overnight” discovery was more than 40 years in the making, and didn’t happen until a century after Einstein first proposed gravitational waves. Weiss spent a lot of time recognizing the many scientists who contributed to LIGO over the years, and noted that today the LIGO Scientific Collaboration includes more than one thousand people from 83 different organizations.

More discovery to come

The future of gravitational wave astronomy is fascinating, according to Weiss. With the VIRGO interferometer in Italy and LIGO-India (INDIGO) joining the LIGO facilities at Hanford, Washington and Livingston, Louisiana, scientists will be able to triangulate to get a better idea about where detected gravitational waves originate. The eLISA mission of the European Space Agency would be a huge interferometer in space that could possibly spot gravitational waves with longer lengths, created by such events as the mergers of supermassive black holes. The LISA Pathfinder mission successfully tested some of the technology earlier this year, and the ESA just this week put out a call for concepts for the next phase of the project. Most interesting is the possibility to detect gravitational waves from almost the instant of the Big Bang, which could be spotted as density variations in the cosmic microwave background.

“I fully expect that if there are gravitational waves that come from inflation, in the next ten years they’ll be found,” Weiss predicted.

A full house at the UW enjoyed the engaging lecture by Weiss.

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Astronaut Hadfield sheds light on the darkest dark

Being afraid of the dark might be considered an indicator against a career as an astronaut. But retired Canadian astronaut Chris Hadfield knew two things as a youngster.

“I always wanted to be an astronaut,” Hadfield said during a talk last month at Town Hall Seattle. And, as a child he was deathly afraid of what might be lurking in the shadows or under the bed in the dark at night. Hadfield has written a children’s book, The Darkest Dark (Little, Brown Books for Young Readers, 2016) aimed at helping youngsters overcome their fears. It was released on September 13, the day of his event in Seattle.

Hadfield’s interest in space was fueled by his reading list as a kid. He read Jules Verne and Edgar Rice Burroughs. He was a big fan of the original Star Trek series and wanted to be Buck Rogers.

“It was all fantasy,” he said. “It was all science fiction. It was reading all of the different books and wanting some day to maybe be a spaceman and to go on space adventures.”

“Opening one of those books was permission to have an imagination,” Hadfield added.

The impossible becomes real

That imagination took Hadfield on many a flight around the universe in his sturdy cardboard box spaceship. It was all kind of a lark until the summer of 1969, the year he turned 10, when he watched on television as Neil Armstrong and Buzz Aldrin walked on the Moon.

Chris Hadfield

Astronaut Chris Hadfield spoke at Town Hall Seattle last month about his new book, The Darkest Dark, aimed at helping kids overcome their fears. Hadfield was afraid of the dark as a child. Photo: Greg Scheiderer.

“What I looked at was Buzz and Neil,” Hadfield recalled. “These weren’t Buck Rodgers, these weren’t James Tiberius Kirk, these weren’t actors, these weren’t fantasy. These were real people. Neil was just a guy. He and Buzz did something very brave, very dangerous, very difficult, but they did it. They succeeded.”

“On the morning of that day of July 20 it was impossible to walk on the Moon,” he noted, “and yet by bedtime Neil and Buzz had put those foot prints all around the Eagle lander.”

It was Hadfield’s a-ha moment: the impossible can really happen.

“Impossible things happen as the result of somebody having a crazy, comic-book kind of inspiration and then working extremely hard and changing who they were,” Hadfield said. Even though Canada didn’t even have a space program at the time, he devoted most of what he did in life to preparing for his dream, so some day he could “put on a (spacesuit) and go to a place where nobody had ever been before.”

Preparation beats the demons

Preparation and practice chased away Hadfield’s demons and he made it to the astronaut corps, a member of NASA’s fourteenth astronaut class, in the summer of 1992. He flew space shuttle missions in 1995 and 2001. The first thing he did after reaching orbit on that first mission was to float over and look out the window.

“It’s the darkest dark you can imagine,” Hadfield explained. “The world is separate and the rest of it goes on forever.”

“Every window on the space ship has nose prints on it because astronauts are always there just trying to see and understand the rest of the universe,” he added. “It is a magnificent, humbling experience to have the world and the universe pouring by your window and to be living in a place where magic suddenly became real.”

In 2012 and 2013 Hadfield was a member of two International Space Station missions, commander of one. He became the first Canadian to walk in space.

“It is the most incredible experience of my life to be holding on to a spaceship with one hand, to be the very first person from my country—wearing a flag that means a lot to me—to be trusted to go do this on behalf of the millions of folks who might have wanted to be up there,” Hadfield said. “To have the whole world reassuringly spinning next to me, but to look the other way, to look out into the eternity of space, to truly, absolutely see the darkest dark there is.”

Hadfield read from The Darkest Dark and took audience questions at the end of his presentation. And, as you might expect from the guy who played David Bowie tunes from space, there was a song, as Hadfield played, in its world premiere, a video and song related to the book.

Further reading

Our post about Hadfield’s 2013 visit to Seattle, in which he talked about playing guitar and other space oddities.

More books by Chris Hadfield


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our efforts to bring you coverage of astronomy events.)

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LIGO, LSST, AOT set for alphabet soup week

A talk by a founder of LIGO and a closer look at the LSST are the highlights of our astronomy calendar for the week.

Wave of the future

Rainer Weiss

Dr. Rainer Weiss. MIT photo: Bryce Vickmark.

Gravitational waves have been all the rave since they were first and finally detected last year. Dr. Rainer Weiss, one of the founders of the Laser Interferometer Gravitational-wave Observatory (LIGO) will give a lecture titled, “Gravitational Wave Astronomy: A New Way to Explore the Universe” on Tuesday, October 25 at 7:30 p.m. in room 130 of Kane Hall on the University of Washington campus in Seattle. Weiss began his work on gravitational waves with a classroom exercise in a general relativity course given at MIT way back in 1967. He will discuss the history of gravitational waves proposed by Einstein, go over the results of the LIGO project, and look into the future of gravitational wave astronomy.

All sign-ups for the free lecture have been taken, but you can watch a live stream of the talk on Tuesday. You can also sign up for the waiting list should seating become available. The talk is part of the Frontiers of Physics public lecture series from the UW College of Arts and Sciences.

AOT goes LSST

AOT LSSTTwo University of Washington scientists involved in the Large Synoptic Survey Telescope (LSST) will talk about the project at a special Friday edition of Astronomy on Tap Seattle at 7 p.m. October 28 at Peddler Brewing Company in Ballard. Doctors John Parejko and David Reiss will explain the LSST, currently under construction in Chile and targeted for being fully operational by 2023. The LSST will image and catalogue tens of billions of galaxies and stars and find more than three million exploding stars and six million asteroids and comets over the next decade, effectively creating a 10-year, multi-color, ultra high-resolution movie of the night sky. It will collect an astounding 20 terabytes of data every night. Parejko and Reiss will talk about the LSST telescope and camera design, the software challenges associated with processing such a huge data set, and the science to be gained from mining the sky in 4-D.

Astronomy on Tap Seattle is organized by graduate students in astronomy at the UW, this month in concert with TEDxSeattle and the LSST. It’s free. It’s always a good idea to bring a chair, as the combination of beer and astronomy is tremendously popular!

Star parties and planetarium shows

The Island County Astronomical Society will hold a free public star party on the evening of Friday, October 28 at Fort Nugent Park in Oak Harbor.

The Spokane Astronomical Society will hold a special Halloween star party beginning at 5:30 p.m. Saturday, October 29 at the club’s dark-sky observing site near Fishtrap Lake on Miller Ranch Road East near Sprague.

Haunted Night SkyIt’s Spook-tober at the Pierce College Science Dome, and this Saturday, October 29 will be the last day for its kids’ planetarium show called “Haunted Night Sky.” Participants will be able to find creatures in the night sky, build a Frankenstein satellite, and take a tour of the Sea of Serpents on the Moon, the Witch’s Head Nebula, and other spooky places in the universe. Best for kids ages 3-12. Shows are scheduled for 12:30 p.m. and 2 p.m. Cost is $3.

Futures file

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

Up in the sky

Venus flirts with Saturn and Jupiter has an encounter with the Moon this week. The Sky This Week from Astronomy magazine and This Week’s Sky at a Glance from Sky & Telescope have more observing highlights for the week.

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Learning about LIGO at Astronomy on Tap

The most recent gathering of Astronomy on Tap Seattle brought to town two scientists working in one of the most groundbreaking areas of astronomy: detection of gravitational waves.

Nature was kind to us

Jeff Kissel, a control systems engineer at the LIGO Hanford Observatory, talked about how exciting it was when they switched on advanced LIGO back in September 2015.

“Boom! Right out of the gate we saw this whopper of an event,” Kissel said, detecting gravitational waves from the merger of a pair of stellar-mass black holes. “Nature was very kind to us.”

What they spotted at Hanford and at LIGO in Livingston, Louisiana was a match.

“Inside our data, which is almost always noise, we saw this very characteristic wave form that was predicted by general relativity,” Kissel recalled. They found gravitational waves from a couple of other black-hole mergers in the following months.

“This is the beginning of gravitational wave astronomy,” Kissel said.

Gravitational waves oscillate through spacetime in a way
demonstrated
by this animation. Credit: ESA–C.Carreau

Kissel pointed out that LIGO only detects a small part of the gravitational wave spectrum. As with light, gravitational waves can come in a wide range of wavelengths with periods ranging from milliseconds to billions of years. Longer-length waves might come from the mergers of galactic nuclei, or even from quantum fluctuations from the early universe.

“There’s a whole zoo of things to find out there,” Kissel said. He anticipates more ground-based observatories as well as some space LIGOs that could have detector arms millions of kilometers long.

How LIGO works

LIGO sounds awfully complicated, but, broken down, the idea is pretty simple. Jenne Driggers
is a Caltech postdoctoral scholar stationed at the LIGO Hanford Observatory, where her gig is improving the sensitivity of the interferometers. Driggers explained that, essentially, they shoot a laser beam into a splitter that sends beams down two equal arms four kilometers long. The beams reflect from mirrors and return to be put back together.

A simplified look at how LIGO works. A laser beam is split and sent down two equal
arms four kilometers long, then reflected back by mirrors. When they return to be
recombined, they will usually cancel each other out and no light will get to the detector.
But if a gravitational wave distorts the system, the light will be spotted by the detector.
Credit: T. Pyle, Caltech/MIT/LIGO Lab

“When they recombine they can be exactly out of phase, and then there’s no laser light (at the detector),” Driggers said. “They cancel each other out totally. Or the lengths will change and these two electromagnetic waves can add up, and so we do get some light.”

When that happens it means that a gravitational wave has distorted the LIGO arms ever so slightly. They measure the light received at the detector to learn more about the wave.

In practice it’s a lot more complicated. It all happens in a total vacuum to avoid any distortion from air. The mirrors are suspended from a system of four pendulums, which helps to eliminate vibration. The mirrors are highly reflective pieces that each weigh around 100 pounds and cost half a million dollars. The laser is about the best there is.

“The laser wavelength itself is our ruler that we’re using to measure the distance between those two mirrors,” Driggers said, “and we need to be able to measure that distance to 10-19 meters.”

“This is one of the highest-power, frequency stable, power-stable lasers on the planet,” she added.

Driggers invited people to tour LIGO Hanford. Public tours are held twice each month, and groups of 15 or more can arrange for a private tour.

Up next: LSST

Astronomy on Tap Seattle is presented and organized by astronomy graduates students at the University of Washington. Their next event is planned for Friday, October 28 at Peddler Brewing Company in Ballard and will feature UW scientists Dr. John Parejko and Dr. David Reiss, who are working on the Large Synoptic Survey Telescope project. The events are free. Enjoy beer and astronomy!

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Astronaut visit a hot ticket this week

An astronaut visit to Seattle is the highlight of this week’s area astronomy calendar, but if you don’t have a ticket already you may be out of luck.

Spaceman: An Evening With Astronaut Mike Massimino will be happening at 5:30 p.m. Friday, October 14 at the Museum of Flight, but as of this writing the event is sold out. The evening’s events include a reception, lecture, and signing of Massimino’s new book Spaceman: An Astronaut’s Unlikely Journey to Unlock the Secrets of the Universe (Crown Archetype, 2016). Massimino is a veteran of two space shuttle missions, including the final servicing mission to the Hubble Space Telescope. If you’d like to go to Friday’s event, you might watch the museum’s website in case additional tickets become available or a waiting list is established. You can pick up the book, at least, at the link above or by clicking the photo at left.

The Boeing Employees’ Astronomical Society will hold its monthly meeting Thursday, October 13, with social time starting at 6:30 p.m. and the evening program beginning at 7 p.m. The meeting will be held in the Boeing “Oxbow” Recreation Center, Building 9-150, Room 201. Non-Boeing attendees are welcome but will need an escort; visit the website for details.

haunted-night-skyIt’s Spook-tober at the Pierce College Science Dome, which will be presenting a kids’ show called “Haunted Night Sky” on Saturdays through Halloween. Participants will be able to find creatures in the night sky, build a Frankenstein satellite, and take a tour of the Sea of Serpents on the Moon, the Witch’s Head Nebula, and other spooky places in the universe. Best for kids ages 3-12. Shows are scheduled for 12:30 p.m. and 2 p.m. each Saturday. Cost is $3.

Futures file

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

Up in the sky

Eagle-eyed early birds can spot Mercury and Jupiter together in the east just before dawn on October 11. The Sky This Week from Astronomy magazine and This Week’s Sky at a Glance from Sky & Telescope have more observing highlights for the week.

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Equinox sunset watch, Tyson visit highlight week’s calendar

A visit from astrophysicist Neil deGrasse Tyson, the final Jacobsen Observatory open house of the year, and a seasonal sunset watch are the highlights of this week’s calendar of astro-events in the Seattle area.

Tyson, director of the Haden Planetarium in New York, narrator of the recent Cosmos television series, author, and host of the StarTalk radio show and podcast, will speak at Seattle’s Paramount Theatre on two nights this week, Wednesday, September 21 and Thursday, September 22, both at 7:30 p.m. Some tickets are still available for both appearances.

Ring in autumn

AlicesAstroInfo-145Join Alice Enevoldsen of Alice’s Astro Info at Solstice Park in West Seattle at 6:30 p.m. Thursday, September 22 to enjoy the first sunset of autumn. The equinox sunset watch will be Enevoldsen’s thirtieth such event, part of her NASA Solar System Ambassador service. The event is free, low-key, and always informative.

TJO wraps its season

Theodor Jacobsen ObservatoryThe final open house of the year is set for 8 p.m. Wednesday, September 21 at the Theodor Jacobsen Observatory on the University of Washington campus in Seattle. The talk for the evening, reservations for which are already all spoken for, will be by student Anya Raj, who has been interning with NRAO-NM over the summer and who has built a dual-dipole radio telescope. Raj will talk about amateur radio astronomy and making your own radio telescope. Volunteers from the Seattle Astronomical Society will be on hand in the observatory dome to conduct tours and, if the sky is clear, offer looks through its vintage telescope.

The popular open house series will be on hiatus for the fall and winter and will resume in April.

Club events

Seattle Astronomical SocietyThe Seattle Astronomical Society will hold its monthly meeting at 7:30 p.m. Wednesday, September 21 in room A102 of the Physics/Astronomy Building on the University of Washington campus in Seattle. Guest speaker Ethan Kruse, a graduate student in astronomy at the UW, will talk about Proxima Centauri b, the exoplanet recently found orbiting our nearest stellar neighbor. Kruse will discuss how much we know about the planet right now, and what we might learn in the coming years.

By way of preview, check our articles about a talk by Kruse at an Astronomy on Tap Seattle event from earlier this year, and about a presentation by Prof. Rory Barnes at Pacific Science Center last month exploring the potential habitability of the planet.

Tacoma Astronomical SocietyThe Tacoma Astronomical Society plans one of its public nights for 9 p.m. Saturday, September 24 at the Fort Steilacoom campus of Pierce College. The indoor presentation will be about the reasons for the seasons as we shift into fall. Weather permitting, club members will have telescopes out for looking at the sky.

Futures file

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

  • World Space Week events October 4–7 at the UW Planetarium
  • The BP Astro Kids November 12 look at the craters of the Moon

Up in the sky

The ice giants Uranus and Neptune are well-placed for observing this week. The Sky This Week from Astronomy magazine and This Week’s Sky at a Glance from Sky & Telescope offer additional observing highlights for the week.

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