Ancient organic material, mysterious methane on Mars

This low-angle self-portrait of NASA's Curiosity Mars rover shows the vehicle at the site from which it reached down to drill into a rock target called "Buckskin" on lower Mount Sharp. Image Credit: NASA/JPL-Caltech/MSSS
This low-angle self-portrait of NASA’s Curiosity Mars rover shows the vehicle at the site from which it reached down to drill into a rock target called “Buckskin” on lower Mount Sharp. Image Credit: NASA/JPL-Caltech/MSSS

From a NASA News Release

NASA’s Curiosity rover has found new evidence preserved in rocks on Mars that suggests the planet could have supported ancient life, as well as new evidence in the Martian atmosphere that relates to the search for current life on the Red Planet. While not necessarily evidence of life itself, these findings are a good sign for future missions exploring the planet’s surface and subsurface.

The new findings – “tough” organic molecules in three-billion-year-old sedimentary rocks near the surface, as well as seasonal variations in the levels of methane in the atmosphere – appear in the June 8 edition of the journal Science.

Organic molecules contain carbon and hydrogen, and also may include oxygen, nitrogen and other elements. While commonly associated with life, organic molecules also can be created by non-biological processes and are not necessarily indicators of life.

“With these new findings, Mars is telling us to stay the course and keep searching for evidence of life,” said Thomas Zurbuchen, associate administrator for the Science Mission Directorate at NASA Headquarters, in Washington. “I’m confident that our ongoing and planned missions will unlock even more breathtaking discoveries on the Red Planet.”

“Curiosity has not determined the source of the organic molecules,” said Jen Eigenbrode of NASA’s Goddard Space Flight Center in Greenbelt, Maryland, who is lead author of one of the two new Science papers. “Whether it holds a record of ancient life, was food for life, or has existed in the absence of life, organic matter in Martian materials holds chemical clues to planetary conditions and processes.”

Although the surface of Mars is inhospitable today, there is clear evidence that in the distant past, the Martian climate allowed liquid water – an essential ingredient for life as we know it – to pool at the surface. Data from Curiosity reveal that billions of years ago, a water lake inside Gale Crater held all the ingredients necessary for life, including chemical building blocks and energy sources.

“The Martian surface is exposed to radiation from space. Both radiation and harsh chemicals break down organic matter,” said Eigenbrode. “Finding ancient organic molecules in the top five centimeters of rock that was deposited when Mars may have been habitable, bodes well for us to learn the story of organic molecules on Mars with future missions that will drill deeper.”

Seasonal Methane Releases

In the second paper, scientists describe the discovery of seasonal variations in methane in the Martian atmosphere over the course of nearly three Mars years, which is almost six Earth years. This variation was detected by Curiosity’s Sample Analysis at Mars (SAM) instrument suite.

Water-rock chemistry might have generated the methane, but scientists cannot rule out the possibility of biological origins. Methane previously had been detected in Mars’ atmosphere in large, unpredictable plumes. This new result shows that low levels of methane within Gale Crater repeatedly peak in warm, summer months and drop in the winter every year.

“This is the first time we’ve seen something repeatable in the methane story, so it offers us a handle in understanding it,” said Chris Webster of NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California, lead author of the second paper. “This is all possible because of Curiosity’s longevity. The long duration has allowed us to see the patterns in this seasonal ‘breathing.'”

Finding Organic Molecules

To identify organic material in the Martian soil, Curiosity drilled into sedimentary rocks known as mudstone from four areas in Gale Crater. This mudstone gradually formed billions of years ago from silt that accumulated at the bottom of the ancient lake. The rock samples were analyzed by SAM, which uses an oven to heat the samples (in excess of 900 degrees Fahrenheit, or 500 degrees Celsius) to release organic molecules from the powdered rock.

SAM measured small organic molecules that came off the mudstone sample – fragments of larger organic molecules that don’t vaporize easily. Some of these fragments contain sulfur, which could have helped preserve them in the same way sulfur is used to make car tires more durable, according to Eigenbrode.

The results also indicate organic carbon concentrations on the order of 10 parts per million or more. This is close to the amount observed in Martian meteorites and about 100 times greater than prior detections of organic carbon on Mars’ surface. Some of the molecules identified include thiophenes, benzene, toluene, and small carbon chains, such as propane or butene.

In 2013, SAM detected some organic molecules containing chlorine in rocks at the deepest point in the crater. This new discovery builds on the inventory of molecules detected in the ancient lake sediments on Mars and helps explains why they were preserved.

Finding methane in the atmosphere and ancient carbon preserved on the surface gives scientists confidence that NASA’s Mars 2020 rover and ESA’s (European Space Agency’s) ExoMars rover will find even more organics, both on the surface and in the shallow subsurface.

These results also inform scientists’ decisions as they work to find answers to questions concerning the possibility of life on Mars.

“Are there signs of life on Mars?” said Michael Meyer, lead scientist for NASA’s Mars Exploration Program, at NASA Headquarters. “We don’t know, but these results tell us we are on the right track.”

This work was funded by NASA’s Mars Exploration Program for the agency’s Science Mission Directorate (SMD) in Washington. Goddard provided the SAM instrument. JPL built the rover and manages the project for SMD.

April Meeting: The Martians are Coming!

Image: Henrique Alvim Corrêa Illustration
Henrique Alvim Corrêa Illustration

The regular monthly membership meeting of the Cuyahoga Astronomical Association will take place Monday, April 10, beginning at 7:30. Meetings take place at the Rocky River Nature Center; 24000 Valley Parkway; North Olmsted, Ohio, in the Cleveland Metroparks.

“The Martians are Coming! – Astronomical Hoaxes and Panics.” CAA member Steve Gallant will discuss some of the great astronomical hoaxes, including the famous Orson Welles “WAR OF THE WORLDS” radio broadcast of 1938!

Following the presentation, the business portion of the meeting will convene. If Martians have not overrun the auditorium, inciting panic by then.

Public Observing Saturday, August 6

The Cuyahoga Astronomical Association’s (CAA’s) observatory at Letha House Park will be open for public observing Saturday, August 6, from 8:30 to 11:00 PM. Visitors will be treated to telescopic views of the Moon (early), Saturn, and as the sky darkens, deep sky objects such as star clusters. Mars may also be viewed but is becoming more distant from Earth and offers less detail to viewers. Click here for our observatory’s web page for information on how to get to the observatory and advice on attending a star party.

The observatory is operated in cooperation with the Medina County Park District (which owns the property). Restroom facilities are available at the park and, in the event of cloudy or inclement weather, an indoor astronomy program will be offered in place of outdoor observing.

Solstice Celebration a huge success

The night of June 21 the Cuyahoga Astronomical Association (CAA) participated in the city of Lakewood’s Summer Solstice Celebration. The event, featuring food, music, dance, and frivolity, really focussed on the solstice sunset and the beginning of summer. Representing the CAA, CSU astronomy instructor Jay Reynolds worked with city officials to coordinate safe solar observing through club member telescopes. Reynolds also convinced officials to extend Celebration hours slightly to allow attendees to observe nighttime objects through telescopes.

Reynolds reported that, “In the end, the event drew more than 4,000 to watch a sunset, do some crafts, eat at a food truck (with Lakewood Hospital “Stroke Truck” next to them), look through some awesome telescopes and interact with some really inspiring, kind and generous representatives of the Cuyahoga Astronomical Association!  Really well done!”

A tremendous crowd was present, parking up city streets for blocks and covering the Lakewood Park Solstice Steps at the lakefront. There were lines at food trucks and, later, at telescopes, but plenty of space for families to spread out and enjoy the show — both natural and human-made.

To view a brief video via Twitter, click here.

Here are some photographs made during the celebration….

Photo: Celebration attendees cover the Lakewood Park Solstice Steps as they watch the Lake Erie Sunset. Photo by James Guilford.
Celebration attendees cover the Lakewood Park Solstice Steps as they watch the Lake Erie Sunset.
Photo: Girl views Sun through a CAA member's telescope. Photo by James Guilford.
Girl views Sun through CAA member Tim Campbell’s telescope.
Photo: Two young ladies view the Sun through a rather short telescope. Photo by James Guilford.
Two young ladies view the Sun through a rather short telescope brought by David Nuti for kids smaller than these!
Photo: Oh yes, the sunset! The Celebration was blessed with a gorgeous Lake Erie sunset. The crowd broke into applause as the last bit of red-orange sun disappeared below the horizon! Photo by James Guilford.
Oh yes, the sunset! The Celebration was blessed with a gorgeous Lake Erie sunset. The crowd broke into applause as the last bit of red-orange sun disappeared below the horizon!

“Immediately after the sun dipped below the horizon, we were mobbed with people,” according to Reynolds. “…they saw very good views of Jupiter and its moons, Mars with polar ice cap and dark regions, and Saturn with its rings, and a lot of people saying WOW!”

Photo: Jay Reynolds, gesturing as attendees view Jupiter, coordinated CAA's participation in the Celebration. Photo by James Guilford.
Jay Reynolds, gesturing as attendees view Jupiter, coordinated CAA’s participation in the Celebration.
Photo: CAA President Bill Murmann watches as young woman views Jupiter. Photo by James Guilford.
CAA President Bill Murmann watches as young woman views Jupiter.
Photo: Long line of folks wanting to view Jupiter through Suzi Dills' big Meade. Sorry about blocking your smiling face, Suzi!
Long line of folks wanting to view Jupiter through Suzi Dills’s big Meade. Sorry about blocking your smiling face, Suzi!
Photo: A long line to view planets through an 1874 Alvin Clark & Sons refractor. Nope, the scope isn't bent, it's only fisheye lens distortion! {whew!} Photo by James Guilford.
A long line to view planets through an 1874 Alvin Clark & Sons refractor, brought by Gary Kader. Nope, the scope isn’t bent, it’s only fisheye lens distortion! {whew!}
Photo: A Dobsonian light-bucket affords views of Saturn to a little girl. Photo by James Guilford.
A Dobsonian light-bucket affords views of Saturn to a little girl.

“Towards the end of the night, the representative of Lakewood came and remarked what a nice group we were and it looks like everyone had a great time. She also remarked how appreciative they were, that CAA supported their event and brought these wonderful telescopes.” Reynolds said, “My comment to her was: “this is who we are, this is what we do”.

Photo: After sunset scopes pointed skyward and offered views of planets Jupiter, Mars, and Saturn. Photo by James Guilford.
After sunset scopes pointed skyward and offered views of planets Jupiter, Mars, and Saturn. Bob Wiersma’s large home-built refractor was a crowd favorite.

Jay Reynolds and the CAA express their thanks for bringing the scopes to the following: Rich & Nancy Whistler, Bill Murmann, Gary Kader, Chris Christe, Dave Nuti, Tim Campbell, Carl Kudrna, Bob Wiersma, Steve Spears, and Suzie Dills. Thanks, too, Anita Kazarian who helped coordinate viewers among the scopes and provided information.