Author Archives: Greg Scheiderer

War in space

If there’s a war in space it won’t involve huge fleets of ships in a shoot-‘em-up accompanied by classical music, as battle is often depicted in science fiction movies.

“Our war in space won’t be particularly a Star Wars version,” according to Linda Dawson, senior lecturer emeritus in physics and space sciences at the University of Washington Tacoma and author of the recent War in Space: The Science and Technology Behind Our Next Theater of Conflict (Springer Praxis Books, 2018). Dawson recently gave a talk about the book at the Museum of Flight.

Linda Dawson
Linda Dawson, author of War in Space, spoke Sept. 14, 2019 at the Museum of Flight. Photo: Greg Scheiderer.

“Spacecraft with weapons in space are still pretty far in the future,” Dawson said. “We’re talking decades.”

Such a conflict would likely destroy every spacecraft in orbit, according to Dawson.

“That kind of a battle would end up disastrous for everyone involved,” she said. “The war would be over in a matter of minutes if that happend just outside of Earth orbit, and it would affect us on Earth for decades.”

That’s not necessarily what is preventing it from happening.

“Space is a very harsh theater of war,” Dawson said, listing the lack of air, extreme temperatures, radiation, and space junk as just the start of the problems such a war would face.

“Access [to space] is expensive and technologically challenging,” Dawson said. “It’s not like we would choose to go to outer space to engage in a war. It’s just that we have spacecraft up there that we all depend on, and so it is an area that is intriguing to countries that don’t agree with each other.”

The likely nature of war in space

War in space would be more subtle than a bunch of big explosions. A variety of weapons, including Earth-to-space, space-to-Earth, and space-to-space varieties are possible. Lasers, missiles, and various “kill vehicles” or “jammers” could be employed to foul up orbiting assets. Space debris itself could be a weapon. Take a look at this video from NASA:

Video Credit: NASA Orbital Debris Program Office at JSC

Earth is at the center of the graphic, and each of the dots represent spacecraft, whether working or not. There’s a lot of junk out there. The Kessler syndrome is a scenario proposed in 70s by NASA scientist Donald Kessler; it posits that if there’s a dense enough amount of debris in space, then one collision or explosion could create a chain reaction of other colllisions or explosions.

“Pretty soon all you have is debris out there and you can’t get through it,” Dawson said. That would make it extremely difficult to operate existing satellites or launch new ones.

We sometimes don’t realize how much we depend on space systems. Wrecking all of those satellites would mess up a lot of things, from our GPS navigation systems to television signals, data exchange, air traffic control, communication systems, and weather forecasting. It would be a total pain.

Though a number of different entities are tracking space debris, it continues to get more challenging. Space X plans to launch 12,000 cube sats to create broadband service; these smaller objects are harder to track. There are unanswered questions about who owns space debris and who can or should clean it up.

“Major spacefaring nations have all been increasingly aggressive with military and surveillance operations in space,” Dawson added.

Preventing war in space

Dawson said the notion of preventing war in space is simple on its surface. It’s the same as preventing war on Earth. You use diplomacy, establish rules of conduct, and operate with openness and cooperation. She said we need more detail than is included in the 1967 Outer Space Treaty, a United Nations effort signed by more than 100 nations that set ground rules for peaceful exploration of space, and we need to figure out if and how existing international law applies to space. It’s all easier said than done.

“The international part of it is the difficult part,” Dawson said. The US has recognized its vulnerabilities in space and is working to protect its own assets, but other countries are doing their own thing.

“I try to be hopeful, but I think the international part of it is the biggest challenge,” Dawson said.

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Also by Linda Dawson:

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Astro Biz: Salute the Sun pale ale

Salute the Sun pale ale

Many businesses, products, and places have names rooted in space and astronomy. We’re featuring one periodically on Seattle Astronomy.

Today’s Astro Biz is Salute the Sun pale ale from Elysian Brewing Company. Salute the Sun is a seasonal brew that is only available from April through July each year.

We’re big fans of Elysian at Seattle Astronomy; their Space Dust IPA is one of the house beers at headquarters.

For some reason beer and booze appear prominently among Astro Biz posts. Salute the Sun is the 114th Astro Biz to date. Those include 12 beers, six wines, six taverns, three breweries or distilleries, and one cocktail. Cheers!

More info:

Hubble’s latest pic of Saturn is a pretty good one

The notion of a picture being worth a thousand words can often be an understatement. Witness the newest, just-released photo of Saturn captured by the Hubble Space Telescope.

Saturn by Hubble
The NASA/ESA Hubble Space Telescope’s Wide Field Camera 3 observed Saturn on 20 June 2019 as the planet made its closest approach to Earth this year, at approximately 1.36 billion kilometers (845 million miles) away. (Photo: NASA, ESA, A. Simon (Goddard Space Flight Center), and M.H. Wong (University of California, Berkeley))

This image is the second in a yearly series of snapshots taken as part of the Outer Planets Atmospheres Legacy (OPAL) project, according to news releases from the European Space Agency and the Space Telescope Science Institute. OPAL is helping scientists to understand the atmospheric dynamics and evolution of our Solar System’s gas giant planets. In Saturn’s case, astronomers will be able to track shifting weather patterns and other changes to identify trends.

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Astro Biz: Meteor Shower Blonde Ale

Many businesses, products, and places have names rooted in space and astronomy. We’re featuring one periodically on Seattle Astronomy.

Today’s Astro Biz is Meteor Shower Blonde Ale from Ghostfish Brewing Company. This brew won a silver medal in the gluten-free beer category at the 2017 Great American Beer Festival. It is brewed with malted millet, brown rice, and Noble German Perle hops. All of Ghostfish’s offerings are gluten free.

More info:

Celestial Pig Pens and new tricks for old scopes

It takes a lot of detective work to figure out the nature of a type Ia supernova. Celestial Pig Pens and new tricks from old telescopes are contributing to the effort. That’s what we learned at the most recent meeting of Astronomy on Tap Seattle.

Messy Siblings: Supernovae in Binary Systems

Dr. Melissa Graham is a project science analyst for the Large Synoptic Survey Telescope, working out of the Astronomy Department at the University of Washington. Her main research focus is supernovae. In particular, she’s doing a lot of work on type Ia supernovae, which occur in binary star systems. One of the stars involved will be a carbon-oxygen white dwarf star.

“It’s a star that wasn’t massive enough to fuse anything else inside the carbon layers,” Graham explained. Outer layers of hydrogen and helium are thrown off in a planetary nebula phase, so the carbon and oxygen are what’s left.

Melissa Graham
Melissa Graham. UW photo.

“Carbon-oxygen white dwarf stars are very compact, very dense, about the size of the Earth but they can be up to about 1.4 times the mass of the Sun,” Graham said. These stars are pretty stable as stars go, so they don’t blow up under normal circumstances.

“When we do see these kind of supernovae that are clearly the explosion of carbon-oxygen white dwarf stars we have to wonder why,” she said. It turns out there are two possible scenarios. The binary can be a pair of carbon-oxygen white dwarf stars that spiral in on each other, merge, and then explode. Or the binary can include one white dwarf and a more typical hydrogen-rich companion star.

“In this case the companion star can feed material onto this carbon-oxygen white dwarf star, might make it go over 1.4 solar masses, become unstable, and then explode,” Graham said.

Which is which?

The key to figuring out which of these scenarios actually occurred is to take a look at the area around the supernova. If the companion is a more hydrogen-rich companion star, the neighborhood can get a little messy.

“It’s sort of like a celestial Pig Pen star that leaves a lot of material lying around,” Graham said. A blast from a supernova can interact with this material and cause it to brighten. The trouble is that astronomers typically only observe type Ia supernovae for a couple of months; they fade quickly. So if this extra material is far away from the event, they might not see the interaction. The answer is patience, to look at the supernova sites for up to 2-3 years after.

Graham did exactly that, using the Hubble Space Telescope to keep an eye on the locations of 65 type Ia supernovae.

“Out of these 65, I very luckily found one” in which there was brightening much later. They checked the spectrum of the light and found hydrogen, a sure sign that the companion in this particular type Ia supernova was a Pig Pen. Graham suspects that up to five percent of such explosions involve messy sibling stars.

Graham looks forward to having the Large Synoptic Survey Telescope (LSST) come on line. She expects it will find some 10 million supernovae in a decade.

“This marks a massive increase in our ability to both find and characterize supernovae,” she said.

Old scope, new tricks

While we wait for LSST an old workhorse telescope is doing interesting work in a similar vein. Professor Eric Bellm of the UW works with the Zwicky Transient Facility (ZTF), which uses the 48-inch telescope at Palomar observatory in California. The scope is a Schmidt, completed in 1948, and for years it was the largest Schmidt telescope in the world. It’s main function at first was to use its wide-field view of the sky to create maps that helped astronomers point Palomar Mountain’s 200-inch Hale Telescope.

Eric Bellm
Eric Bellm. UW photo.

The 48-inch was used to do numerous sky surveys over the years. It discovered many asteroids, and Mike Brown used it to find the dwarf planets he used to kill Pluto. The old photographic plates gave way to modern CCDs, and Bellm became the project scientist for the Zwicky Transient Facility—named for astronomer Fritz Zwicky, a prolific discoverer of supernovae—in 2011.

They outfitted the scope with a new camera with 16 CCDs that are four inches per side. They got some big filters for it and put in a robotic arm that could change the filters without getting in the way of the camera. They started surveying in March of last year and can photograph much of the sky on any given night.

“That’s letting us look for things that are rare, things that are changing quickly, things that are unusual,” Bellm said.

Examples of what the ZTF has found include a pair of white dwarfs that are spinning rapidly around each other, with a period of just seven minutes. They can see the orbits decay because of gravitational wave radiation. It has discovered more than 100 young type 1a supernovae. And it found an asteroid with the shortest “year” of any yet discovered; its orbit is entirely within that of Venus.

It’s doing the same sort of work that the LSST will do when it comes online.

“It’s super cool that we’ve got this more than 70 year old telescope that we’re doing cutting-edge science with thanks to the advances of technology,” Bellm said.

Astronomy on Tap Seattle is organized by graduate students in astronomy at the University of Washington, and typically meets on the fourth Wednesday of each month at Peddler Brewing Company in Ballard. The next event is set for September 25.

Astro-events and stargazing sites

We’ve been beefing up our astronomy resources of late, adding quite a few events to our calendar and stargazing sites to our maps.

Craters of the Moon
Craters of the Moon National Monument in Idaho is one of the IDA’s International Dark-sky Parks. Photo: US National Park Service

We were inspired to add some stargazing sites by a recent article on the Travel Awaits website. “The 7 Most Incredible Stargazing Sites In The U.S.” by Juanita Pike did not include any Northwest locations, but we went through the International Dark-Sky Association‘s list of dark sky places and added those in our region to our stargazing site maps. We did hop out of the Northwest, barely, for one of them. The frighteningly named Massacre Rim Wilderness Study Area is a certified IDA International Dark Sky Sanctuary just south of the Oregon border in northwestern Nevada.

The maps have grown to have quite a few sites on them. The northwest map is up to about 70, and the Seattle-area map has a stargazer’s dozen.

Astronomy events

Our events calendar is a pretty robust listing of astronomy events in the region. It’s helpful that we can pull events directly from the calendars of several different organizations, including the Seattle, Tacoma, Palouse, and Island County astronomical societies. Some others take a little more legwork. For example, we recently discovered a listing of events about exoplanets that will be running at the Jefferson County Library through early October, and the Southern Oregon Skywatchers shared a list of pending events in their neck of the woods.

Destination: Moon

Apollo 11 Command Module Columbia
The Apollo 11 command module “Columbia” will be at the Museum of Flight through Sept. 2. Photo: Greg Scheiderer.

One of the coolest events of the year is about the come to an end. The Destination: Moon exhibit about the Apollo 11 mission has been at the Museum of Flight since April and will be closing next week, September 2. The Apollo 11 command module “Columbia” is the centerpiece of the exhibit, but there are a great many other interesting items on display as well. (Check out our article about the exhibit when it was in St. Louis last year, and our preview of the MOF version.)

For the final days of Destination: Moon the museum will offer extended hours and discount pricing. Normal hours for the museum are 10 a.m. until 5 p.m. daily. From August 28 through September 2 they’ll stay open from 5-9 p.m. and admission will be discounted during those late hours: $15 for adults and seniors and $10 for youth. Destination: Moon is a separate, $10 ticket; you have to arrive at or after 5 p.m. to qualify for the discount.

We always say that we comb the Internet for astronomy events so that you don’t have to! Please feel free to share any events by your club or organization.

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Astro Biz: Orion Commercial Partners

Many businesses, products, and places have names rooted in space and astronomy. We’re featuring one periodically on Seattle Astronomy.

Today’s Astro Biz is Orion Commercial Partners. ORION is a Seattle-based real estate services and investment firm. We spotted their sign outside the West Seattle Corporate Center (they lease space there) as we were on our way to the West Seattle Health Club.

We like that their logo is a riff on Orion’s belt.

More info: