Tag Archives: Bob Abel

Meeting the Martians and getting snapshots of far-away planets

It’s possible that some extraterrestrials were at the most recent Astronomy on Tap Seattle gathering, at which we explored the possibility of life on Mars and looked at exciting new techniques for capturing images of exoplanets.

We have met the Martians and they are us—maybe

“Are we all Martian-Americans? We still don’t know,” said Bob Abel, a professor of applied physics at Olympic College and collaborator with the University of Washington’s Large Synoptic Survey Telescope Group. Abel gave a talk titled, “Where Are the Martians?” at Astronomy on Tap Seattle April 26.

Giving a quick geological and topographical history of Mars, Abel said that the Red Planet is just one-half the diameter of Earth, and thus has just one-eighth the volume of Earth, so Mars cooled off pretty quickly.

Mars Mudstones

Curiosity shot this image in Gale Crater on Mars. The mudstones indicate a long history of standing water in that location. Photo: NASA.

“During the early formation of the solar system, it would have cooled to the point where liquid water could exist on its surface before the Earth got to that point,” Abel said, adding that it’s clear that water was once abundant on Mars. The rovers Spirit and Curiosity both landed in craters that used to be lakes, and Opportunity set down on the edge of what scientists think was once a salty sea.

In addition, Abel said that Spirit found opaline silica in Gusev Crater on Mars.

“The place where you find this on Earth is near geysers and hydrothermal vents,” Abel said. You’ll find heat, water, and minerals around these vents. “You’ve got all the stuff for life, and you find the most primitive life clustered around these on Earth.”

Bob Abel

Prof. Bob Abel of Olympic College gave a talk about Mars and Martians at Astronomy on Tap Seattle April 26, 2017. Photo: Greg Scheiderer.

The surface of Mars is awfully barren now, but life could have conceivably existed there in the distant past. Scientists have found meteorites from Mars on Earth, and inside some of those meteorites they’ve found structures that look like nanobacteria. The debate continues over whether these are biological or not.

“It’s still somewhat up in the air, but it’s tantalizing evidence,” Abel said. “The question still remains, did life start earlier on Mars, since it was capable of being inhabited? And by the time Earth was habitable, did meteorites come to Earth and start life on Earth?”

The investigation continues.

As for present-day Mars, while the surface appears devoid of life, we may find something if we dig a little deeper. Abel said that Curiosity detects occasional outbursts of methane on Mars. He pointed out that most methane on Earth is created by biology.

“I’m personally rooting for flatulence, but we don’t know yet what’s causing it,” he laughed. But, through measurements made by many different Mars orbiters, we’ve learned that the planet’s outer core is molten. So beneath the surface there is heat, water, hydrocarbons, and soil: everything life wants. Abel recalled a talk last year by Penelope Boston, head of the NASA Astrobiology Institute.

“She can’t see how life doesn’t exist below the surface of Mars,” Abel said.

Snapshots of exoplanets

Getting photographs of exoplanets—planets orbiting far-away stars—is a relatively new field within astronomy. The first such images were captured just eight years ago or so. Benjamin Gerard said the technology and capabilities within the field are advancing rapidly. Gerard, a doctoral student in physics and astronomy at the University of Victoria in British Columbia, uses the Gemini Planet Imager to trick out pictures of planets near stars that are many light years away. These photos can be useful for figuring out the components of a planet’s atmosphere and whether it has oceans and continents.

Gerard

Doctoral student Benjamin Gerard gave a talk about his work imaging exoplanets at Astronomy on Tap Seattle April 28. Photo: Greg Scheiderer.

Gerard said the main challenges in exoplanet imaging are resolution and contrast. He explained that the key to good resolution is adaptive optics. If you’ve looked through a telescope you have likely had nights when the objects you observe appear to be wiggling around because of atmospheric turbulence. Gemini corrects for this with adaptive optics.

Light from the object hits a deformable mirror as well as a component called a wave-front sensor. The sensor measures the amount of turbulence, sends the information to the mirror’s actuators, which can correct for the aberration.

“The mirror deforms once every millisecond,” Gerard said. “This aberration gets corrected and is constantly re-focused onto the camera. Once it reaches that point this image that is very turbulent suddenly becomes much more stable and we can get much better resolution.”

Gerard said this is a plus for ground-based telescopes.

“With this technique, we can basically take a ten-meter telescope and make it like we were in space,” he said. “With adaptive optics we actually do better than any space telescope in resolution.”

The problem of contrast is apparent to anyone who has visited social media, which is full of bad-contrast photos. Especially common are pics of people posed in front of windows. Often the people appear as silhouettes because the light from the window is way brighter. While exoplanets don’t pose in front of cosmic windows, contrast is a huge problem when it comes to getting the images.

“A planet like Earth is about ten billion times dimmer than it’s host star,” Gerard pointed out. Using a coronagraph helps block out the light of the star and remove its glare from the image. They also use a technique called angular differential imaging to overcome aberrations within the instruments. This is a little bit counter-intuitive to the amateur astrophotographer who typically uses an instrument rotator during long exposures to compensate for the apparent motion of objects caused by the rotation of the Earth.

“For exoplanet imaging this is actually helpful, so we turn off the instrument rotator and the planet appears to rotate with respect to the view of the fixed telescope instrumental aberrations,” Gerard said. “We can distinguish one from the other.” Computer algorithms can later put images made in this way back together to create even greater contrast.

Gerard hopes they’ll be able to do even better in the near future. The Wide Field Infrared Survey Telescope (WFIRST) is scheduled to launch in the mid-2020s. It will have a deformable mirror that should have the capability to image smaller planets like Earth.

“This is many orders of magnitude better than we can do on ground-based telescopes, because on a space telescope you’re much more stable,” Gerard said. “On the Hubble Space Telescope now we can’t reach this sort of contrast because there is no deformable mirror.”

Since Gerard gave the talk NASA announced an independent review of WFIRST that could change its timeline and instrumentation.


The next Astronomy on Tap Seattle gathering is set for May 24 at Peddler Brewing Company.

Share

Busy week ahead on the astro calendar

There’s something for everyone on this week’s astro calendar, with a new scale model solar system opening, two great lectures, a theater/science mashup, and a variety of club events on the docket.

A new scale model of the solar system that you can explore through geocaching opens today, May 1, on Bainbridge Island. Check out our article or podcast from last week to learn more.

Proxima b

You’ve probably heard by now of the discovery of a planet orbiting our nearest stellar neighbor, Proxima Centauri. (If not, check out our article featuring UW professor Rory Barnes discussing the possibility of the habitability of Proxima b.) The UW Astrobiology Program and the NASA Astrobiology Institute will host a panel discussion about the planet at 7 p.m. Wednesday, May 3 in room 120 of Kane Hall on the university’s campus in Seattle.

The panelists include Guillem Anglada-Escude, lead discoverer of the planet and University of London lecturer; Victoria Meadows, University of Washington astrobiology professor and primary investigator for the Virtual Planetary Laboratory; Barnes; and Olivier Guyon, University of Arizona professor and project scientist for the Subaru Telescope.

It’s free but registration is required; as of this writing there were still some tickets available.

Searching for Martians

Bob Abel talkMars may have been habitable before Earth was, and might be still. So where are the Martians? Olympic College professor Bob Abel will give a talk about the history of Mars and the prospects for past, present, and future life there at 6 p.m. Thursday, May 4 in room 117 of the Engineering Building on the Olympic College campus in Bremerton. It’s free.

Abel gave a talk on the same topic last week at Astronomy on Tap Seattle. Our recap of that event is coming soon.

Astronomy Day at MOF

The Museum of Flight celebrates Space Day during its Free First Thursday at 5 p.m. May 4. Local astronomy clubs will be on hand with information about their activities and they’ll have telescopes for observing if the weather cooperates. A special presentation at 6 p.m. will take a look at the technical challenges of getting Apollo to the Moon, and what that means for present-day space efforts. Tony Gondola, a solar system ambassador and coordinator of the museum’s Challenger Learning Center will be the speaker.

The event runs through 9 p.m.

Mashing up science and theater

Centrifuge2Infinity Box Theatre Project will present Centrifuge 2 at 8 p.m. this Friday and Saturday, May 5 and 6, at Stage One Theater on the North Seattle College campus. Centrifuge pairs science writers and playwrights to craft brand-new one-act plays featuring current science. Seattle Astronomy’s Greg Scheiderer participated in the event last year and will be one of the science writers again this time around. Check out our article and podcast from last year to learn more about Centrifuge and Infinity Box.

Open house at TJO

The Theodor Jacobsen Observatory at the University of Washington will hold one of its bimonthly open houses at 9 p.m. Wednesday, May 3. The topic for the evening’s talk had not been published as of this writing. Volunteers from the Seattle Astronomical Society will be on hand to offer tours of the observatory and, weather allowing, a look through its vintage telescope.

Club events

The Tacoma Astronomical Society will hold its monthly meeting at 7:30 p.m. Tuesday, May 2 in room 175 of Thompson Hall on the University of Puget Sound campus in Tacoma. The topic will be club participation in viewing the August 21, 2017 total solar eclipse.

The club will also offer one of its free public nights at 9 p.m. Saturday, May 6 at the Fort Steilacoom campus of Pierce College. The indoor session will be a presentation about constellations. They’ll break out the telescopes for observing if the sky is clear.

The Spokane Astronomical Society plans its monthly meeting for 7:30 p.m. Friday, May 5 at the planetarium at Spokane Falls Community College. Club member Nick Monkman will talk about the ABCs of finding objects in the night sky.

The Seattle Astronomical Society plans its monthly free public star parties for 9 p.m. Saturday, May 6 at two locations: Green Lake in Seattle and Paramount Park in Shoreline. Bad weather causes cancellations, so watch the website for updates.

You can always scout out future events on our calendar page.

Share

Mars events on tap for week of Astronomy Day

There are a couple of Mars-themed events on the docket for Red Planet buffs this week, plus star parties and Astronomy Day celebrations.

AOT April 26Astronomy on Tap Seattle returns to Peddler Brewing Company in Ballard at 7 p.m. Wednesday, April 26. Two talks are on the schedule. Bob Abel, a professor of applied physics at Olympic College, will give a lecture titled, “Where are the Martians?” Abel will look at the history and current state of our nearby neighbor, Mars, and examine the possibilities of life in its past, present, and future. University of Victoria doctoral student Benjamin Gerard will discuss his research on “Imaging Worlds Beyond Our Solar System.” He’ll show pictures of other worlds and explain how we use the most powerful telescopes and specially designed optical systems to distinguish an exoplanet from the overwhelming glare of its host star.

Abel, by the way, is scheduled to give a talk on a similar topic at Olympic College on May 4.

Astronomy on Tap Seattle is free, but buy some beer. Bring your own chair to create a front-row experience in the Peddler beer garden!

Red Planet insider

There’s more Mars in store when NASA Jet Propulsion Laboratory engineer Terry Himes gives a talk at 2 p.m. Saturday, April 29 at the Museum of Flight. Himes is a veteran of many Mars missions, such as the InSight and Phoenix landers. He’s also worked on Dawn, Deep Impact/Epoxi, and more. Learn what it takes to get there, and back.

Star parties

There are several star parties scheduled for the weekend. The monthly Covington Community Park Star Party is planned for 9 p.m. Friday, April 28 at the park in Covington. The star party is a joint effort of the Seattle Astronomical Society, Boeing Employees Astronomical Society, and Tacoma Astronomical Society. It’s weather dependent, so watch the websites for more information.

The Battle Point Astronomical Association will celebrate Astronomy Day beginning at 3 p.m. Saturday, April 29 at their Edwin Ritchie Observatory in Battle Point Park on Bainbridge Island. Daytime activities include viewing the Sun, a walk through the solar system, and tours of the observatory. Once it gets dark they’ll look at Jupiter and other celestial delights if weather permits.

OMSI and Rose City Astronomers in Portland celebrate Astronomy Day with star parties at two locations: Rooster Rock and Stub Stewart state parks in Oregon. They’ll get going at sunset, weather permitting.

You can always scout out future events on the Seattle Astronomy calendar.

Share