Tag Archives: Seattle Astronomical Society

A look at the Perseverance mission to Mars

Astronomy events are few and far between these days as clubs cope with stay-at-home restrictions and institutional closures in response to the coronavirus pandemic. Most meetings and public star parties have been canceled for March and April while a few wait to see how events unfold.

Like some in arts and entertainment, astronomy clubs are looking for ways to take at least some of their activities online. Case in point, the Seattle Astronomical Society last week held its monthly meeting using the Zoom videoconferencing platform. Members enjoyed a presentation by SAS president John McLaren, who also is a NASA Solar System Ambassador, about the upcoming Perseverance mission to Mars.

A history of Mars exploration

McLaren gave a quick history of Mars exploration, from Mariner 4 which sent 21 photos back from Mars after a fly by in 1965 to the present work of Curiosity. He noted that Viking 1 in 1976 sent back the first photo from the surface of Mars. It was no accident that it shot its own foot.

Viking's foot on Mars
The first Viking 1 photo from Mars. Credit: NASA

“If we can only get one picture back, this is the most important picture, because they want to see how well the landing gear performed,” McLaren explained. “If they can see how the landing gear did, it gives them an idea of how they can improve the next lander.”

Unfortunately, experiments conducted by Viking were thought to rule out the possibility of life on Mars, though McLaren noted that there’s still some discussion about whether those experiments were conducted and interpreted properly. In any event, the zeal for Mars exploration cooled somewhat until the mid-1990s, when a Mars meteor discovered on Earth was found to contain what could be fossilized bacteria. This sparked new scientific interest in the Red Planet.

We returned to the surface of Mars in 1997 with Sojourner and Pathfinder, which proved we could land and drive around a rover on Mars.

“It truly was the Pathfinder that led us to design more sophisticated vehicles,” McLaren said. Spirit and Opportunity followed in 2004 and Curiosity landed in 2012.

Same car, new features

Perseverance, known as Mars 2020 until a recently concluded naming contest, will be something of a souped-up version of Curiosity. It’s based on the same design, but they’ve re-engineered the wheels, as those on Curiosity showed heavy wear unexpectedly early in its mission. Perseverance will also carry different instruments more specialized for astrobiology and geology. It will drill core samples and leave them cached on Mars awaiting a possible future return mission. And its cameras in general are more powerful and versatile than those of Curiosity. It’s mission is different, too. While Spirit and Opportunity were sent to follow the water and Curiosity is trying to figure out if Mars could have supported microbial life, Perseverance will actually be looking for evidence of that life.

Perseverance landing site on Mars
A photo by Mars Reconnaissance Orbiter of the planned landing site for Perseverance. The target is the smooth, purple-ish area to the right of what looks like a river delta. Credit: NASA/JPL-Caltech/ASU

A big challenge for the engineers will be delivering Perseverance to its landing site, which is in a crater called Jezero on the edge of what appears to have once been a lowland sea. There’s what looks like a former river delta on the edge of Jezero crater.

“The hope is that water was here for a long time, water flowed down here building this silt, that this is the most likely location where they hope to find any signs of life,” McLaren said.

A small target

The challenge is that the landing ellipse, the target they need to hit, is ten times smaller by area than that of Curiosity and some 300 times smaller than Pathfinder’s. They’ll used a technologically enhanced version of the sky crane technique that worked for Curiosity to try to hit that target.

The window for a possible launch opens on July 17 this year and McLaren said NASA expects to land Perseverance on Mars on February 18, 2021.

You can watch a recording of McLaren’s presentation on the Seattle Astronomical Society website.

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Amateur astronomy in the age of coronavirus

Coronavirus and social distancing cannot deprive us of our enjoyment of astronomy. One can make the case that the best way to enjoy the hobby is with a telescope in your back yard in the middle of the night, as noted in my most recent tweet of Sky and Telescope’s weekly update of stuff to see.

On the other hand amateur astronomy is also a highly social endeavor. There are jillions of astronomy clubs all over the country with members devoted to putting on interesting meetings and to sharing their enjoyment of the heavens with their neighbors. The members of these clubs also rely on each other as answerers of how-to questions. Our last post was about Goldendale Sky Village, which is being designed as a spot in which it will be easy for members to observe the night sky together.

In the coronavirus era the comet Churyumov–Gerasimenko has been replaced on astronomy’s hardest-to-spell list by the word “canceled.” As astronomy groups call off their events one sees this AP-Style preferred spelling about as often as “cancelled,” which most dictionaries list as OK, too. Grammar police from both sides tend to weigh in with little impact.

Calling the whole thing off

Regardless of the spelling, a great majority of official astronomy events are being canceled these days. Part of the challenge is that many astronomy organizations hold their gatherings at schools or colleges, libraries, museums, and other sorts of places that are now buttoned up. Just this morning Washington governor Jay Inslee announced a ban on any confab of more than 50 people, and said even smaller meetings had to meet strict guidelines for hygiene and social distancing. Officials urged people to avoid any “unnecessary interactions” at least for the next couple of weeks. As much as I love them, astronomy events probably fall into that category.

The Seattle Astronomical Society has canceled its March meeting which would have been on the 18th. The club is looking at streaming more meetings, as it did with a remote guest speaker last month. Similarly, the Rose City Astronomers in Portland have ditched their regular meeting set for tonight, though club members can check out an online meeting via Zoom. Clubs in Bainbridge Island, Everett, Whatcom County, Island County, Tacoma, Bellevue, Tri-Cities, and Eugene also have nixed many of their events at least for March and some in April.

Taking it online

A couple of major events are planning to go virtual. The Northeast Astronomy Forum (NEAF), perhaps the hobby’s biggest trade show, is switching to a one-day online event set for April 4. The next meeting of the American Astronomical Society, scheduled for Madison, Wisconsin May 31 to June 4, is looking at moving from an on-site/in-person conference to a fully remote/virtual one.

The author social distancing
Social distancing in astronomy! The author caught the 2012 transit of Venus by himself at a remote county park in northern California. Photo: Greg Scheiderer.

These are hard times for astronomy bloggers, too. The Museum of Flight, Oregon Museum of Science and Industry, Pacific Science Center, and Town Hall Seattle are all closed, and these have provided many great astronomy events that we’ve covered over the years. In addition, we haven’t heard anything official from Astronomy on Tap Seattle about the status of its monthly gathering, but it typically draws way more than 50 people, is held in a beer garden, and all of those have been closed, so we can connect the dots on that.

Nevertheless we soldier on! We’ve got a little stretch of clear sky going, so social distance yourself and get out and enjoy it while it’s here. We’ll keep blogging it up and, once this virus is licked, we’ll see you at the next star party. In the meantime, wash your hands.

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Mapping the Moon

When we went on a road trip to a new place when I was a kid my dad would pick up a map from the nearest gas station. There were no gas stations on the way to the Moon, but the first astronauts to land there had a map anyway, thanks to the work of Harlan “Buzz” Reese and colleagues. His son, Tom Reese, talked about his father’s work at the most recent meeting of the Seattle Astronomical Society.

“What I’m honored to share tonight are images mainly from our dad’s collection, which for more than 50 years was pretty much just stuffed in boxes and cardboard tubes, but we now think of them as artifacts,” Tom Reese said. His father, who passed away in 2013, worked for many years at the Aeronautical Chart and Information Center (ACIC) in St. Louis. It was an office of the Air Force and was considered the premier mapping organization in the country. The elder Reese was a civilian who worked on the project creating charts of the Moon for NASA.

“They worked with the photographs from any source they could get, the best pictures that were available,” Reese said. That included images made by ground-based telescopes and lunar orbiters, and later photos shot by astronauts during Apollo missions. There was no image-editing software in the 1960s, but the folks at ACIC did have a cut-and-paste operation; they literally pieced together many of their charts by making copies of photographs, cutting them out, and building maps of larger areas as mosaics of many images. Some of them were huge, room-sized. They’d sometimes build these maps on the entire floor of a large room and walk around in stocking feet so as not to damage them too much. The charts include handwritten notes and tell-tale identification of the people who made them.

This photo of the Apollo 11 landing site was made by Apollo 10 and includes a handwritten overlay by Harlan Reese. Photo: Tom Reese.

“My dad’s smeared fingerprints and careful mapping marks are also a down-to-Earth tribute to the other 400,000 human beings whose efforts made the journey possible,” Reese said.

Reese, an independent journalist, photographer, author, artist and teacher whose work as a newspaper and magazine photojournalist was nominated for Pulitzer Prizes during his career at The Seattle Times, spoke of a sense of awe and wonder when making a photograph of the Moon.

“I think it was with the same sense of wonder that my dad saved all these things that were actually scraps of his work,” Reese said, “but I also think he thought of these as a gift to be shared.”

Part of that wish came true this year, when several of the charts were included in the Destination Moon exhibit that wrapped up earlier this month at the Museum of Flight. Reese said he hopes the entire collection can some day wind up in a place where it can continue to tell a part of the story of the Apollo missions.

Tom Reese spoke about his father’s Moon mapping at the Sept. 18, 2019 meeting of the Seattle Astronomical Society. Photo: Greg Scheiderer.

It’s amazing to think that the lunar orbiters that preceded Apollo were shooting photos using film, processing that film in space and then sending the images to Earth via radio. Today’s digital cameras on spacecraft capture far greater resolution. For the cartographers who mapped the Moon there was a good deal of art to go with the science.

“On the early maps of the Earth you can see where they would come to the limit of the known world and simply mark down ‘terra incognita’ or ‘beyond this point there be dragons,’” Reese said. “In the early mapping of the Moon precision was key, of course. But the audacity to fire three men packed into a rattling tin can to an unexplored world also required calculating on the unforeseen.” The mappers analyzed all of the data they had to give accurate representation of the sizes of and distances between lunar features so that the maps would be useful guides.

You can see many of the images Reese shared during his presentation on his website.

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Seattle is just like Mars, and other lessons from a 3-D trip

Attendees at the most recent gathering of the Seattle Astronomical Society went on an entertaining and informative 3-D trip to Mars, and learned that Seattle is just like the Red Planet.

Antonio Paris

Antonio Paris

Our tour guide was Dr. Antonio Paris, chief scientist at the Center for Planetary Science, assistant professor of astronomy and astrophysics at St. Petersburg College in Florida, and author of Mars: Your Personal 3D Journey to the Red Planet (Center for Planetary Science, 2018).

Paris said he loves Mars and expects that humans will be going there sooner than later.

“I suspect that, the way things are going, probably in about 10 to 15 years we’re going to be on Mars,” he said, adding that he doesn’t think anyone is going to go it alone.

“Mars, in my personal opinion, is going to be an international effort, both with corporations as well as the government,” Paris said.

The book was something of a spinoff of an exhibit about Mars that Paris helped put together at the Museum of Science and Industry in Tampa. The exhibit proved pretty popular, and the book seemed the next natural step. Proceeds from book sales support the work of the Center for Planetary Science.

Paris featured fantastic 3-D images of a great many Martian geological features in his presentation. While his Ph.D. is in astronomy, he’s really morphed into something of a rock hound.

“We are primarily geologists that are studying all of the geological features here on Earth,” he said, “and we’re trying to compare and contrast them with what we see on the lunar surface, what we see on Mercury, Venus, and all of the terrestrial planets.”

Paris called the process comparative planetology.

Ripples

Ripple marks such as those shown in this photo from the rover Opportunity were deposited by water moving back and forth. Image: NASA/JPL

“If I look at something here on Earth and I can determine how that thing happened,” he said, “and I see the same thing on Mars, I can deduce that the same processes have occurred, most likely.”

That caveat was included on most of his deductions, but the comparisons are pretty compelling. For example, Paris passed around a flat piece of rock with ripple marks on it that he collected in the Canyonlands in Utah. Such ripple marks are created by water moving back and forth over the rock, and the Canyonlands piece looks exactly like stuff the rovers have seen on Mars.

Paris also showed photos of rock formations made when moving or freezing water breaks up bedrock, and wears it down into small pebbles. At least, that’s how it happens on Earth.

Potholes on Mars

This set of images compares the Link outcrop of rocks on Mars with similar rocks seen on Earth. Image: NASA/JPL-Caltech/MSSS and PSI

“We call that either fragmented sidewalk or conglomerate terrain,” he said. Here in Seattle, especially after our recent cold and snowy weather, we just call it a pothole, and that’s how the Emerald City is like the Red Planet! Potholes all over the place!

Paris does a lot of rock hunting in the American southwest, which has a lot of Mars analog sites that scientists and NASA use in their Mars work. These include Moenkopi in Arizona, Canyonlands, the Mojave Desert, Death Valley, and the Flagstaff area.

The website for the Center for Planetary Science notes that Paris will make a presentation in Portland in September at a time and place not yet published. Dollars to Voodoo Doughnuts it will be with Rose City Astronomers. Stay tuned.

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Hanging out with comet hunter David Levy

One of the great perks of membership in the Seattle Astronomical Society is that the speakers at its annual banquet are typically dynamite. This year’s event featured one of the giants of astronomy, David H. Levy, who has discovered 22 comets, including the famous Shoemaker-Levy 9 that slammed into Jupiter in 1994.

Levy’s talk was highly autobiographical, which is fitting because his own autobiography, A Nightwatchman’s Journey: The Road Not Taken, is scheduled to come out this summer. Levy’s story is not necessarily complete, however; he’s still at it.

“Astronomers never really retire; you certainly don’t retire from being an amateur astronomer because it’s in your blood, it’s what you do, it’s what you live for,” Levy noted.

“I don’t think I’m ever going to discover another comet,” he said. “I’m still searching, because the search is so much fun!”

Several events from his youth seemed to steer Levy to a life in astronomy. Leslie Peltier discovered the Comet Kesak-Peltier in June of 1954 when Levy was about six years old. Later, when he was in high school, Levy was assigned to do a report on a book of his choosing. He picked Starlight Nights: The Adventures of a Star-Gazer, an autobiography of Peltier that had just been released. Levy couldn’t put it down, and it remains his all-time favorite book.

His parents sent him to Twin Lake Camp for three summers, and he didn’t like it much, but one year while returning to his cabin after a fireworks display he saw a shooting star and took it as an omen.

Then, in 1960 Levy had to do a public speech on any topic. He chose comets. Just before graduation, Levy crashed while riding his bicycle and broke his arm. A cousin gave him a book about the solar system as a get-well present. He devoured it.

“Any doubt that I was going to be interested in the night sky after that was erased,” Levy said. “All there was to do was astronomy.”

David Levy

Seattle Astronomy’s Greg Scheiderer (left) visited with comet hunter and author David H. Levy at the Seattle Astronomical Society banquet Jan. 27.

Like many astronomers amateur and professional, Levy has kept a log book with notes about all of his observing sessions. His dates back to 1959 when he saw a partial solar eclipse, and as of the end of January included an amazing 20,922 sessions.

“Each one of them I cherish,” Levy smiled, noting about note-taking that, “If you don’t write it down, you haven’t done it.”

His first session looking for comets is dated December 17, 1965. It was nearly 19 years until he found his first in 1984. He’d logged a half dozen by 1990. Most of his comet hunting was visual in the early days, but it was around 1990 that he started doing photographic searches in partnership with Gene and Carolyn Shoemaker. One of the comets they discovered together is Shoemaker-Levy 9.

The gag among comet hunters is that to get famous your discovery has to become really bright. Shoemaker-Levy 9 didn’t do that, but the spectacular collision of its fragments with Jupiter in 1994 was a historic event.

“What it’s famous for is what it taught us,” Levy said “In colliding with Jupiter, it gave Earth a lesson in the origin of life.”

“It doesn’t prove that a comet collision means that life is going to start on a world,” he added. “What it does show is that when comets collide with a world, life eventually can start. It doesn’t mean that it does, but it’s one of the ways it does.”

“We’re all the progeny of comets,” Levy said.

His presentation was enjoyable and his autobiography promises to be an engaging read. It will be his 35th book. Watch for news about it in this space later this year.

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Comet hunter David H. Levy to keynote Seattle Astronomical Society banquet

David Levy

David H. Levy. Photo: Wendee Levy

Comet hunter extraordinaire David H. Levy will be the keynote speaker at the annual banquet of the Seattle Astronomical Society January 27, 2019. The event will begin at 5 p.m. with a social hour and silent auction before dinner at 6 p.m.

Levy has had a hand, or should we say an eyeball, in 23 comet discoveries. Perhaps the most famous one is comet Shoemaker-Levy 9 that spectacularly smashed into Jupiter in July 1994. He has written 34 books, mostly about astronomy. Titles include The Quest for Comets, a biography of Pluto-discoverer Clyde Tombaugh in 2006, and his tribute to Gene Shoemaker, Shoemaker by Levy: The Man Who Made an Impact. He has also written for Sky and Telescope, Parade, Sky News and, Astronomy magazine.

Reservations for the banquet are on sale now online for Seattle Astronomical Society members, and will be available to the general public beginning January 6.

Please note: while Seattle Astronomy’s Greg Scheiderer is a member of the Seattle Astronomical Society, there’s no official connection between the club and this blog

Books by David H. Levy:

Mars is here!

It’s been a big year for Mars. The InSight lander is on the way to the Red Planet, scheduled to land November 26 on a mission to take the vital signs of Mars. There’s a big dust storm on Mars just as it reaches opposition this week, its closest approach to Earth since 2003. Oh, and organics have been found on Mars.

We may have buried the lede on that one.

Mars

July 18 image of Mars by the Hubble Space Telescope. (Image credit NASA, ESA, and STScI)

Dave Cuomo and Keith Krumm from the Pacific Science Center were guest speakers at the July meeting of the Seattle Astronomical Society, and discussed all things Mars.

The discovery of organics on Mars is also evidence that science is not necessarily fast. The work came out of a hole the Curiosity rover drilled in a Mars rock way back in 2015. The papers outlining the discovery just came out earlier this year.

“What it found in a rock that is about three-and-a-half billion years old was organic molecules,” Cuomo said. The substance found was kerogen, which Cuomo called, “a gooey precursor to petroleum.”

Cuomo repeatedly stressed that this does not, not, not mean that there is or ever was life on Mars.

“What we have found is evidence that the building blocks for life on Mars certainly did exist three-and-a-half billion years ago,” he said. “This was the first time that we found clear evidence that this was there.”

Cuomo noted that we know a good bit about the history of the surface of Mars.

“Mars certainly was a warmer and a wetter environment that could have supported life, that life could have evolved on,” he said. “What we don’t know—and this is what InSight is going to help us find out—is how long Mars was more Earth-like.” The longer that warm, wet environment lasted, the greater the potential that life could have arisen.

InSight

Krumm noted that InSight is something of an interplanetary RN.

“It’s going to be taking Mars’ vital signs,” he said. It will use a seismometer to take Mars’s pulse, a heat flow probe to measure its temperature, and the Rotation and Interior Structure Experiment, RISE, will check its reflexes, precisely tracking the location of the lander to determine just how much Mars’ north pole wobbles as it orbits the Sun. Cuomo said a big part of the mission’s purpose is to find out if Mars has a molten core today.

“It has volcanoes, so we know at some point in the past it had a molten interior,” he said. “It had a magnetosphere—the remnants of it are frozen in the rocks—but it does not have an active magnetosphere.”

InSight will help us figure out of the core solidified, or if there’s some other reason for the loss of the magnetosphere. Krumm and Cuomo showed this video about the InSight mission.

The Pacific Science Center plans an event for watching the InSight landing on November 26. Watch this space for details!

Dust storm

The rover Opportunity is powered by solar panels, and the dust storm on Mars has blocked the Sun to an extent that Opportunity has shut down. NASA hasn’t heard from Opportunity since June 10. It’s programmed to switch back on every so often, and shut right back down if it doesn’t find power. Cuomo said that can only go on for so long.

“It’s possible it won’t wake up,” he said. If that happened, it would be a sad end to a tremendous run. Opportunity and its twin, Spirit, landed on Mars in 2004 on missions expected to last 90 days. The last contact with Spirit, stuck in the sand, was in March 2010, while Opportunity, up until last month, at least, has been running for more than 14 years.

Opposition

Mars reached opposition to Earth on the evening of July 26 in Pacific Daylight Time, and will be at its closest approach to Earth for the year on Tuesday, July 31. Those dates are different because of the geometry of the elliptical orbits of the two planets. In any case, we’re closer to Mars than at any time since the great apparition of 2003, which is good news for amateur astronomers. The bad news is that the dust storm could foil our attempts to image and observe surface features of Mars. There was word this week, however, that the storm is fading. Bright red Mars will be a good observing target for the rest of the summer and into early fall.

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