Making the Case for a Mission to the Martian Moon Phobos

Phobos. From where did it arise or arrive? Is it dry or wet? Should we flyby or sample and return? Should it be Boots or Bots? (Photos: NASA, Illus.:T.Reyes)

Ask any space enthusiast, and almost anyone will say humankind’s ultimate destination is Mars. But NASA is currently gearing up to go to an asteroid. While the space agency says its Asteroid Initiative will help in the eventual goal of putting people on Mars, what if instead of going to an asteroid, we went to Mars’ moon Phobos?

Three prominent planetary scientists have joined forces in a new paper in the journal Planetary and Space Science to explain the case for a mission to the moons of Mars, particularly Phobos.

“Phobos occupies a unique position physically, scientifically, and programmatically on the road to exploration of the solar system,” say the scientists. In addition, the moons may possibly be a source of in situ resources that could support future human exploration in circum-Mars space or on the Martian surface. But a sample return mission first could provide details on the moons’ origins and makeup.

The Martian moons are riddles, wrapped in a mystery, inside an enigma. Phobos and its sibling Deimos seem like just two asteroids which were captured by the planet Mars, and they remain the last objects of the inner solar system not yet studied with a dedicated mission. But should the moons be explored with flybys or sample-return? Should we consider “boots or bots”?

The publications and mission concepts for Phobos and Deimos are numerous and go back decades. The authors of “The Value of a Phobos Sample Return,” Murchie, Britt, and Pieters, explore the full breadth of questions of why and how to explore Phobos and Deimos.

Dr. Murchie is the principal investigator of the Mars Reconnaissance Orbiter’s CRISM instrument, a visible/infrared imaging spectrometer. He is a planetary scientist from John Hopkins’ Applied Physics Lab (APL) which has been at the forefront of efforts to develop a Phobos mission. Likewise, authors Dr. Britt, from the University of Central Florida, and Dr. Pieters, from Brown University, have partnered with APL and JPL in Phobos/Deimos mission proposals.

A MRO HiRise image of the Martian moon Phobos. Taken on March 23, 2008. Phobos has dimensions of 27 × 22 × 18 km, while Deimos is 15 × 12.2 × 11 km. Both were discovered in 1877 at the US Naval Observatory in Washington, D.C. (Photo: NASA/MRO/HiRISE)
An MRO HiRise image of the Martian moon Phobos. Taken on March 23, 2008. Phobos has dimensions of 27 × 22 × 18 km, while Deimos is 15 × 12.2 × 11 km. Both were discovered in 1877 at the US Naval Observatory in Washington, D.C. (Photo: NASA/MRO/HiRISE)

APL scientists are not the only ones interested in Phobos or Deimos. The Jet Propulsion Laboratory, Ames Research Center and the SETI Institute have also proposed several missions to the small moons. Every NASA center has been involved at some level.

But the only mission to actually get off the ground is the Russian Space Agency’s Phobos-GRUNT[ref]. The Russian mission was launched November 9, 2011, and two months later took a bath in the Pacific Ocean. The propulsion system failed to execute the burns necessary to escape the Earth’s gravity and instead, its orbit decayed despite weeks of attempts to activate the spacecraft. But that’s a whole other story.

The Russian-led mission Phobos-Grunt did not end well; under Pacific swells to be exact. Undaunted Russian scientists are pressing for Phobos-Grunt 2. (Credit: CNES)
The Russian-led mission Phobos-Grunt did not end well; under Pacific swells to be exact. Undaunted Russian scientists are pressing for Phobos-Grunt 2 (illus.), an improved lander with sample-return. Proposed for 2020s (Credit: CNES)

“The Value of a Phobos Sample Return” first discusses the origins of the moons of Mars. There is no certainty. There is a strong consensus that Earth’s Moon was born from the collision of a Mars-sized object with Earth not long after Earth’s formation. This is just one possibility for the Martian moons. Murchie explains that the impacts that created the large basins and craters on Mars could have spawned Phobos and Deimos: ejecta that achieved orbit, formed a ring and then coalesced into the small bodies. Alternative theories claim that the moons were captured by Mars from either the inner or outer solar system. Or they could have co-accreted with Mars from the Solar Nebula. Murchie and the co-authors describe the difficulties and implications of each scenario. For example, if captured by Mars, then it is difficult to explain how their orbits came to be “near-circular and near-equatorial with synchronous rotational periods.”

To answer the question of origins, the paper turns to the questions of their nature. Murchie explains that the limited compositional knowledge leaves several possibilities for their origins. They seem like D-type asteroids of the outer asteroid belt. However, the moons of Mars are very dry, void of water, at least on their surfaces as the paper discusses in detail. The flybys of Phobos and Deimos by NASA and ESA spacecraft are simply insufficient for drawing any clear picture of their composition or structure, let alone their origins, Murchie and co-authors explain.

If the moons were captured then they have compositions different from Mars; however if they accreted with or from Mars, then they share similar compositions with the early Mars when forming, or from Martian crustal material, respectively.

The paper describes in some detail the problem that billions of years of Martian dust accumulation presents. Every time Mars has been hit by a large asteroid, a cloud of debris is launched into space. Some falls back to the planet but much ends up in orbit. Each time, some of the debris collided with Phobos and Deimos; Murchie uses the term “Witness plate” to describe what the two moons are to Mars. There is an accumulation of Martian material and also material from the impactors covering the surfaces of the moons.  Flyby images of Phobos show a reddish surface similar to Mars, and numerous tracks along the surface as if passing objects struck, plowed or rolled along. However, the reddish hue could be weathering from Solar flux over billions of years.

The paper continues with questions of the composition and how rendezvous missions could go further to understanding the moons makeup and origins, however, it is sample return that would deliver, the pay dirt. Despite how well NASA and ESA engineers have worked to shrink and lighten the instruments that fly, orbit, and land on Mars, returning a sample of Phobos to labs on Earth would permit far more detailed analysis.

SpaceX and Elon Musk claim that they will mount human flight to Mars before 2030. Many others remain less optimistic with hopes to human flights before 2040. (Illustrations: Total Recall, 1990, early artist illustration c.1950s )
SpaceX and Elon Musk claim that they will mount human flight to Mars before 2030. Many others remain less optimistic with hopes of human flights before 2040. (Illustrations: Total Recall, 1990, early artist illustration c.1950s )

Science Fiction writers and mission designers have imagined Phobos, in particular, as a starting point for the human exploration and colonization of Mars. A notable contemporary work is “Red Mars” by Kim Stanley Robinson; however, the story line is dated due to the retirement of the Space Shuttle and the external tanks Robinson clustered to form the colonization vessel. While this paper by Murchie et al. is purely scientific, fiction writers have used the understanding that Phobos is far easier to reach from Earth than is the surface of Mars (see Delta-V chart below).

A diagram showing the stair-step energy needed to travel to places beyond the Earth. Delta-V is the velocity in km/sec to reach a destination. The Delta-Vs a accumulative. (Credit: Wikipedia, Delta-V)
A diagram showing the stair-step energy needed to travel to places beyond the Earth. Delta-V is the speed in km/sec required to reach a destination. As shown, the Delta-Vs are cumulative. Note that it takes an extra 5 km/sec  beyond Phobos to reach the Martian surface; a prime reason for making the journey to the moons of Mars. (Credit: Wikipedia, Delta-V)

Phobos, orbiting at 9,400 kilometers (5,840 miles), and Deimos, at 23,500 km (14,600 miles), above Mars avoids the need for the 7-odd minutes of EDL terror – Entry, Descent, and Landing — and pulling oneself out of the Martian gravity well to return to Earth. Furthermore, there is the interest in using Phobos as a material resource – water, material for rocket fuel or building materials. “The Value of a Phobos Sample Return” discusses the potential of Phobos as a resource for space travelers – “In Situ Resource Utilization” (ISRU), in the context of its composition, how the solar flux may have purged the moons of water or how Martian impact debris covers materials of greater interest and value to explorers.

With so many questions and interests, what missions have been proposed and explored? The Murchie paper describes a half dozen missions but there are several others that have been conceived and proposed to some level over several decades.

At present, there is at least one mission actively pursuing funds. The SETI and Ames proposed “Phobos and Deimos & Mars Environment” (PADME) mission led by Dr. Pascal Lee is competing for Discovery program funding. Such projects must limit cost to $425 million or less and be capable of launching in less than 3 years. They are proposing a launch date of 2018 on a SpaceX Falcon 9. The PADME mission design would reuse Ames LADEE hardware and expertise, however, it does not go so far as what Murchie and co-authors argue – returning a sample from Phobos. PADME would maintain in a synchronized orbit with Phobos and then Deimos foe repeated flybys. The mission is likely to cost in the range of $300 million. Stardust, a relevant mission due to its sample return capsule, launched in 1999 and had costs which likely reached a similar level by end of mission in 2012.

The Russian Space Agency is attempting to gain funding for Phobos-Grunt 2 but possible launch dates continue to be moved back – 2020, 2022, and now possibly 2024.

Return of the Stardust sample inside the Lockheed-Martin developed sample-return capsule. See here upon successful landing in the Utah desert. (Credit: NASA/Stardust)
Return of the Stardust sample inside the Lockheed-Martin developed sample-return capsule. Seen here upon successful landing in the Utah desert. (Credit: NASA/Stardust)

Additionally, each of this papers’ authors has mission proposals described. Dr. Pieters, JPL, and Lockheed-Martin proposed the Aladdin mission; Dr. Britt at APL, also with Lockheed-Martin, proposed the mission Gulliver; both would re-use the Stardust sample-return capsule (photo, above). Dr. Murchie also describes his APL/JPL mission concept called MERLIN (Mars–Moon Exploration, Reconnaissance and Landed Investigation).

Phobos and Deimos are the last two of what one would call major objects of the inner Solar System that have not had dedicated missions of exploration. Several bodies of the Asteroid Belt have been targeted with flybys and Dawn is nearing its second target, the largest of the Asteroids, Ceres.

So sooner rather than later, a spacecraft from some nation (not necessarily the United States) will target the moons of Mars. Targeted Phobos/Deimos missions are also likely to include both flyby missions and one or more sample-return missions. A US-led mission with sample-return in the Discovery program will be strained to meet both criteria – $425 million cost cap and 3 year development period.

Those utilizing the Lockheed-Martin (LM) Stardust design have a proven return capsule and spacecraft buses (structure, mechanisms and avionics) for re-use for cost and time savings. This includes five generations of the LM flight software that holds an incredible legacy of mission successes starting with Mars Odyssey/Genesis/Spitzer to now Maven.

All three proposals by this paper’s authors could be re-vamped and proposed again and compete against each other. All three could use Lockheed-Martin past designs. Cooperation in writing this paper may be an indicator that they will join forces, combine concepts, and share investigator positions on a single NASA-led project. The struggle for federal dollars remains a tough, tight battle and with the human spaceflight program struggling to gain a new footing after Space Shuttle, dollars for inter-planetary missions are likely to remain very competitive. However, it appears a Phobos-Deimos mission is likely within the next ten years.

Further reading:

“The Value of a Phobos Sample Return”, Scott L. Murchie, Daniel T. Britt, Carle M. Pieters, Planetary and Space Science, 1 November 2014

The US Naval Observatory, Great 26″ Refractor Telescope

Past Universe Today story, “Finding Phobos: Discovery of a Martian Moon”

One That Fell to Earth: Researchers Reveal 2012 Novato Meteorite Took a Beating

End of flight fragmentation of the Nov. 18, 2012, fireball over the San Francisco Bay Area (shown in a horizontally mirrored image to depict the time series from left to right). The photographs were taken from a distance of about 40 miles (65 km). Image Credit: Robert P. Moreno Jr., Jim Albers and Peter Jenniskens

What’s the chance of that thump you just heard in your house was a meteorite hitting your roof? That was the case for one family in Novato, California during a fireball event that took place in the north bay area near San Francisco on October 17, 2012.

Researchers have now released new results from analysis of the meteor that fell to Earth, revealing that the “Novato meteorite” was part of numerous collisions over a span of 4 billion years.

There is nothing ordinary about a meteorite whether it just spent 4.4 billion years all alone or spent such time in a game of cosmic pinball, interacting with other small or large bodies of our Solar System. On any given night one can watch at least a couple of meteors overhead burning up, lighting up the sky but never reaching the Earth below. However, in less than two years, Dr. Peter Jenniskens, SETI Institute’s renowned meteor expert was effectively host to two meteorites within a couple hours drive from his office in Mountain View, California.

The first was the Sutter Mill meteorite, a fantastic carbonaceous chondrite full of organic compounds. The second was the Novato meteorite, identified as a L6 chondrite fragmental breccia. which is the focus of new analysis, to be released in a paper in the August issue of Meteoritics and Planetary Science. Early on, it was clear that this meteorite had been a part of a larger asteroidal parent body that had undergone impact shocks.

Analysis of the meteorite was spearheaded by Jenniskens who initially determined the trajectory and orbit of the meteoroid from the Cameras for Allsky Meteor Surveillance (CAMS) which he helped establish in the greater San Francisco bay area. Jenniskens immediately released information about the fireball to local news agencies to ask for the public’s help with the hopes of finding pieces of the meteorite. One resident recalled hearing something hit her roof, and with the help of neighbors, they investigated and soon found the first fragment in their backyard.

Finding fragments was the first step, and over a two year period, the analysis of the Novato meteorite was spread across several laboratories around the world with specific specialties.

Novato N04, found by Bob Verish. The fourth of 6 fragments of the Novato fireball recovered. (Image Credit, B. Verish)
Novato N04, found by Bob Verish. The fourth of six fragments of the Novato fireball recovered. Fusion crust from entry into the Earth’s atmosphere is clearly evident. A 1 centimeter cube is shown for size comparison. (Image Credit, B. Verish, cams.seti.org)

Dr. Jenniskens, along with 50 co-authors, have concluded that the Novato meteorite had been involved in more impacts than previously thought. Dr. Qingzhu Yin, professor in the Department of Earth and Planetary Sciences at the University of California, Davis stated, “We determined that the meteorite likely got its black appearance from massive impact shocks causing a collisional resetting event 4.472 billion years ago, roughly 64-126 million years after the formation of the solar system.”

The predominant theory of the Moon’s formation involves an impact of the Earth by a Mars-sized body. The event resulted in the formation of the Moon but also the dispersal of many fragments throughout the inner Solar System. Dr. Qingzhu Yin continued, “We now suspect that the moon-forming impact may have scattered debris all over the inner solar system and hit the parent body of the Novato meteorite.”

Additionally, the researcher discovered that the parent body of the Novato meteorite experienced a massive impact event approximately 470 million years ago. This event dispersed many asteroidal fragments throughout the Asteroid Belt including a fragment from which resulted the Novato meteorite.

The Novato meteorite strewn field determined by Dr. Jenniskens team's analysis of CAMS allsky images. (Illustration Credit, P. Jenniskens, NASA/SETI)
The Novato meteorite strewn field determined by Dr. Jenniskens team’s analysis of CAMS allsky images. (Illustration Credit, P. Jenniskens, NASA, SETI – cams.seti.org)

The trajectory analysis completed earlier by Dr. Jenniskens pointed the Novato meteorite back to the Gefion asteroid family. Dr. Kees Welten, cosmochemist at UC Berkeley, was able to further pinpoint the time, drawing the conclusion, “Novato broke from one of the Gefion family asteroids nine million years ago.” His colleague at Berkeley, cosmochemist Dr. Kunihiko Nishiizumialso added, “but may have been buried in a larger object until about one million years ago.”

There was more that could be revealed about history of  the Novato meteorite. Dr. Derek Sears a meteoriticist working for the Bay Area Environmental Research Institute in Sonoma, California and stationed at NASA Ames Reserach Center applied his expertise in thermoluminescence. Dr. Sears was involved in the analysis of Lunar regolith returned by the Apollo astronauts using this analysis method.

“We can tell the rock was heated, but the cause of the heating is unclear,” said Dr. Sears, “It seems that Novato was hit again.” As stated in the NASA press release, “Scientists at Ames measured the meteorites’ thermoluminescence – the light re-emitted when heating of the material and releasing the stored energy of past electromagnetic and ionizing radiation exposure – to determine that Novato may have had another collision less than 100,000 years ago.”

From this apparent final collision one hundred thousand years ago, the Novato meteoroid completed over 10,000 orbits of the Sun and with its final Solar orbit, intercepted the Earth, entering our atmosphere and mostly burning up over California. The meteoroid is estimated to have measured 14 inches across (35 cm) and have weighed 176 pounds (80 kg). What reached the ground likely amounted to less than 5 lbs. (~ 2 kg). Only six fragments were recovered and many more remain buried or hidden in Sonoma and Napa counties.

Besides the analysis that revealed the series of likely impact events in the meteoroids history, a team led by Dr. Dan Glavin from NASA Goddard Space Flight Center undertook analysis in search of amino acids, the building blocks of life. They detected non-protein amino acids in the meteorite that are very rare on Earth. Dr. Jenniskens emphasized that the quick recovery of the fragments by scores of individuals that searched provided pristine samples for analysis.

The impact dent on the rooftop of the Webber home in Novato. Luis Rivera points to the dent. (Image Credit, P.Jenniskens, L.Rivera, cams.seti.org)
The impact dent on the rooftop of the Webber home in Novato. Luis Rivera points to the dent. (Image Credit, P.Jenniskens, L.Rivera, cams.seti.org)

Robert P. Moreno, Jr. in Santa Rosa, CA photographed the fireball in greatest detail with a high resolution camera. Several other photos were brought forward from other vantage points. Dr. Jenniskens stated, “These photographs show that this meteorite – now one of the best studied meteorites of its kind – broke in spurts, each time creating a flash of light as it entered Earth’s atmosphere.”

An animated gif of the series of photographs taken by Robert Moreno Jr. (Credit, R. Moreno Jr., NASA, SETI)
An animated gif of the series of photographs taken by Robert Moreno Jr. Click on the image to animate in full resolution. (Credit, R. Moreno Jr., NASA, SETI)

Numerous individuals and groups undertook the search for the Novato meteorite. Dr. Jenniskens trajectory analysis included a likely impact zone or strewn field. People from all walks of life roamed the streets, open fields and hillsides of the north bay in search of fragments. Despite organized searches by Dr. Jenniskens, it was the footwork from other individuals that led to finding six fragments and was the first step which led to these studies that add to the understanding  of the early Solar System’s development.

For Dr. Jenniskens, Novato was part of a trifecta – the April 22, 2012, Sutter Mill meteorite in the nearby foothills of the Sierras, the Novato meteorite and the massive Chelyabinsk airburst event in Russia on February 15, 2013. Throughout this period, Dr. Jenniskens all-sky camera network continued to expand and record “falling stars” – meteors. The number of meteors recorded with calculated trajectories is now over 175,000. The SETI Institute researcher has been supported by NASA and personnel at the institute and ordinary citizens including amateur astronomers that have refined the methods for meteor orbital determination and estimating their size and mass. Several websites have compiled images and results for the Novato meteorite with Dr. Jenniskens’ – CAMS.SETI.ORG being most prominent.

Jill Tarter Video: From Searching For Aliens To Helping Hollywood Stars, And Back Again

SETI's Jill Tarter. Credit: SETI

Imagine you’re a researcher at a cocktail party. You meet Carl Sagan (Carl Sagan!) and he hands you a novel. And it turns out that you are the inspiration for the major character in that book.

What was SETI researcher Jill Tarter’s reaction when this actually happened and she heard about Ellie, the protagonist in Contact?

“I said, ‘Look. Here’s the deal. As long as she doesn’t eat ice cream cones for lunch, nobody’s going to think it’s me.’ That was the thing that was sort of my most peculiar habit of the time,” Tarter recalls in this new video for PBS.

If you can think of all the media attention that surrounded the reboot of Cosmos, imagine that it’s 1997 and Contact has just been made into a movie. Tarter became a celebrity overnight, and describes the impact on her life. But she also explains why searching for life beyond Earth has relevance.

Tarter’s video is just one of several featured in the show “”The Secret Life of Scientists and Engineers.” To get the full story on Tarter’s links to Contact, check out this Universe Today story from 2012 where she reflected on the 15th anniversary of the movie.

Jill Tarter Explains in 30 Seconds Why We’re Searching for Aliens

SETI's Jill Tarter. Credit: SETI

After nearly four decades of of listening for for signs of life in the cosmos, astronomer Jill Tarter is one of a handful of true experts on the Search for Extraterrestrial Intelligence (SETI). And since 1995 we’ve known for certain there are other planets out there; the goal now is to find one that’s habitable.

“Exoplanets are real,” Tarter said recently, talking about how the Kepler planet-hunting mission has changed the concept of SETI. “We are now observing stars where we KNOW there are planets. We’ve gone from having 20-30 potential targets to having thousands of targets. Kepler is telling us WHERE to look, and we are focusing there.”

But so far the search has come up empty. After so long with no luck, why continue? Tarter recently appeared on PBS’s “Secret Lives of Scientists”
and she gave them an answer in less than 30 seconds.

Will We Find Alien Life Within 20 Years? You Can Bet On It.

SETI's Allen Telescope Array monitor the stars for signs of intelligent life (SETI.org)

During a hearing last week before the U.S. House Science and Technology Committee SETI scientists Seth Shostak and Dan Werthimer asserted that solid evidence for extraterrestrial life in our galaxy — or, at the very least, solid evidence for a definitive lack of it — will come within the next two decades. It’s a bold claim for scientists to make on public record, but one that Shostak has made many times before (and he’s not particularly off-schedule either.) And with SETI’s Allen Telescope Array (ATA) continually scanning the sky for any signals that appear intentional, exoplanets being discovered en masse, and new technology on deck that can further investigate a select few of their (hopefully) Earth-like atmospheres, the chances that alien life — if it’s out there — will be found are getting better and better each year.

Would you put your bet on E.T. being out there? Actually, you can.

Thanks to the internet and the apparently incorrigible human need to compete you can actually place a wager on when alien life will be discovered, via an Irish online betting site.

Illustration of Kepler-186f, a recently-discovered, possibly Earthlike exoplanet that could be a host to life. (NASA Ames, SETI Institute, JPL-Caltech, T. Pyle)
Illustration of Kepler-186f, a recently-discovered, possibly Earthlike exoplanet that could be a host to life. (NASA Ames, SETI Institute, JPL-Caltech, T. Pyle)

Typically focused on the results of international sporting matches, PaddyPower.com has also included the announcement of extraterrestrial life in its novelty bet section, hinging on “the sitting President of the USA making a statement confirming without doubt the existence of alternative life beings from another planet.” The odds of such an announcement being made in the years 2015-2018 are currently listed at 100 to one. After that they drop significantly… probably because by then the JWST will be in operation and we will “have the technology.” Stranieri.com also has offered a chance for Italian players of chance to bet on the sitting president discussing life from other planets, with betting open until 2025 for long-term gamblers!

Of course, whether you personally would place a wager on such things is purely personal preference, and neither I nor Universe Today condones or supports gambling, for aliens or otherwise. (And the legalities of doing so and any and all results thereof are the sole responsibility of the reader.) But it is interesting that we now live in a time when wagering on the discovery of alien life sits just a click away from the results of the Kentucky Derby, French Open, or World Cup.

Now if you really want to support the science that will make such a discovery possible — maybe even within our own Solar System — you can “stand up for space” and write your representatives to tell them you want NASA’s planetary science budget to be funded, and rather than gamble your money you can make a donation to support SETI’s ongoing mission here (or even help out yourself via SETI@home.)

And even if all else fails, you could end up with a free coffee courtesy of Dr. Shostak…

Learn more about SETI and how the ATA works here, and read Dan Werthimer’s May 21 statement to the House Committee here.

Source/ht: FloridaToday Space and The Independent

“Two possibilities exist: either we are alone in the Universe or we are not. Both are equally terrifying.”

– Arthur C. Clarke

Are we Ready for Contact?

Credit: José Antonio Peñas/Sinc

A common criticism of science is its quick decision to experiment, without thinking about whether or not it should. While many argue that philosophical implications do not belong within the realm of science, others argue that scientists should absolutely consider the broader implications of their results.

Now, neuro-psychologist Gabriel G. de la Torre from the University of Cádiz is questioning whether or not astronomers, who have previously only looked for signs of extraterrestrial life, should actively send messages from Earth.

The idea that we might not be alone in the universe has been around since at least the fifth century B.C., when the Greek philosopher Democritus posited innumerable worlds, none of which were devoid of life.

With the founding of NASA and other space agencies in the 20th century, human beings began to explore the solar system and actively search for alien life. The most ambitious search began in 1960, when astronomer Frank Drake pointed a radio telescope at two stars similar to our Sun and listened for a signature of intelligence.

Drake’s work inspired the Search for ExtraTerrestrial Intelligence (SETI) project, an initiative that began in the 70s with funding from NASA, but has now evolved toward the collaboration of millions of Internet users for the processing of data from the Arecibo Observatory.

But then there is “Active SETI — also known as METI (Messaging to Extra-Terrestrial Intelligence) — which is the attempt to send messages to potential ETs via radio signals. Some astrophysicists, such as Stephen Hawking, have already warned against the risk this implies for humanity. It would favor the arrival of beings with more advanced technology and unknown intentions.

So “can such a decision be taken on behalf of the whole planet?” asked De la Torre. “What would happen if it was successful and ‘someone’ received our signal? Are we prepared for this type of contact?”

To answer these questions, De la Torre surveyed 116 American, Italian and Spanish university students. The questionnaire assessed their knowledge of astronomy, their religious beliefs, and their beliefs on the likelihood of contact with extraterrestrial intelligent life.

The results indicate that as a species, humanity is still not ready to actively contact a supposed extraterrestrial civilization. The students lacked awareness on many astronomical aspects, despite the enormous progress of science and technology. It also revealed that they lack preparation and would instead rely on political and religious figures.

De la Torre encourages SETI researchers to look for alternative strategies until society can better prepare itself. “This pilot study demonstrates that the knowledge of the general public of a certain education level about the cosmos and our place within it is still poor,” said De la Torre. “Therefore, a cosmic awareness must be further promoted – where our mind is increasingly conscious of the global reality that surrounds us – using the best tool available to us: education.”

The paper has been published in the journal Acta Astronautica.

Kepler Has Found the First Earth-Sized Exoplanet in a Habitable Zone!

Artist's rendering of Kepler-186f (Credit: NASA Ames/SETI Institute/Caltech)

It’s truly a “eureka” moment for Kepler scientists: the first rocky Earth-sized world has been found in a star’s habitable “Goldilocks” zone, the narrow belt where liquid water could readily exist on a planet’s surface without freezing solid or boiling away. And while it’s much too soon to tell if this really is a “twin Earth,” we can now be fairly confident that they do in fact exist.

The newly-confirmed extrasolar planet has been dubbed Kepler-186f. It is the fifth and outermost planet discovered orbiting the red dwarf star Kepler-186, located 490 light-years away. Kepler-186f completes one orbit around its star every 130 days, just within the outer edge of the system’s habitable zone.

The findings were made public today, April 17, during a teleconference hosted by NASA.

“This is the first definitive Earth-sized planet found in the habitable zone around another star,” says lead author Elisa Quintana of the SETI Institute at NASA Ames Research Center. “Finding such planets is a primary goal of the Kepler space telescope. The star is a main-sequence M-dwarf, a very common type.  More than 70 percent of the hundreds of billions of stars in our galaxy are M-dwarfs.”

A visualization of the “unseen” red dwarfs in the night sky. Credit: D. Aguilar & C. Pulliam (CfA)
A visualization of the many “unseen” red dwarfs in the night sky. (CLICK FOR ANIMATION) Credit: D. Aguilar & C. Pulliam (CfA)

Unlike our Sun, which is a G-type yellow dwarf, M-dwarf stars (aka red dwarfs) are much smaller and dimmer. As a result their habitable zones are much more confined. But, being cooler stars, M-dwarfs have long lifespans, offering planets in their habitable zones — like Kepler-186f — potentially plenty of time to develop favorable conditions for life.

In addition, M-dwarfs are the most abundant stars in our galaxy; 7 out of 10 stars in the Milky Way are M-dwarfs, although most can’t be seen by the naked eye. Finding an Earth-sized planet orbiting one relatively nearby has enormous implications in the hunt for extraterrestrial life.

“M dwarfs are the most numerous stars,” said Quintana. “The first signs of other life in the galaxy may well come from planets orbiting an M dwarf.”

Read more: Earthlike Exoplanets Are All Around Us

Still, there are many more conditions on a planet that must be met for it to be actually habitable. But size, composition, and orbital radius are very important first steps.

“Some people call these habitable planets, which of course we have no idea if they are,” said Stephen Kane, an assistant professor of physics and astronomy at San Francisco State University in California. “We simply know that they are in the habitable zone, and that is the best place to start looking for habitable planets.”

Scale comparison of the Kepler-186 system to our inner Solar System (
Scale comparison of the Kepler-186 system and the inner Solar System (NASA Ames/SETI Institute/Caltech)

As far as the planetary system’s age is concerned — which relates to how long life could have potentially had to evolve on Kepler-186f’s surface — that’s hard to determine… especially with M-dwarf stars. Because they are so stable and long-lived, once they’re formed M-dwarfs essentially stay the same throughout their lifetimes.

“We know it’s probably older than a few billion years, but after that it’s very difficult to tell,” BAERI/Ames scientist Tom Barclay told Universe Today. “That’s the problem with M-dwarfs.”

A comparison of the Kepler 186 and Solar systems (NASA/Ames)
A comparison of the Kepler 186 and Solar systems (Presentation slide, NASA/Ames)

The exoplanet was discovered via the transit method used by NASA’s Kepler spacecraft, whereby stars’ brightnesses are continually monitored within a certain field of view. Any dips in luminance reveal the likely presence of a passing planet.

Because of its small size — just slightly over 1 Earth radius — and close proximity to its star, Kepler-186f can’t be observed directly with current telescope technology.

The Gemini North telescope on the summit of Mauna Kea (Gemini Observatory/AURA)
The Gemini North telescope on the summit of Mauna Kea (Gemini Observatory/AURA)

“However, what we can do is eliminate essentially all other possibilities so that the validity of these planets is really the only viable option,” said Steve Howell, Kepler project scientist and a co-author on the paper.

Using the latest advanced imaging capabilities of the Gemini North and Keck II observatories located atop Mauna Kea in Hawaii, astronomers were able to determine that the signals detected by Kepler were from a small orbiting planet and not something else, such as a background or companion star.

“The Keck and Gemini data are two key pieces of this puzzle,” Quintana said. “Without these complementary observations we wouldn’t have been able to confirm this Earth-sized planet.”

Kepler-186f joins the other 20 extrasolar worlds currently listed in the Habitable Exoplanets Catalog, maintained by the Planetary Habitability Laboratory at the University of Puerto Rico at Arecibo. To date 961 exoplanets have been confirmed through Kepler observations, with 1,696 total confirmed altogether. (Source)

Artist's conception of the Kepler Space Telescope. Credit: NASA/JPL-Caltech
Artist’s conception of the Kepler Space Telescope. Credit: NASA/JPL-Caltech

Read more: Mega Discovery! 715 Alien Planets Confirmed Using a New Trick on Old Kepler Data

Whether Kepler-186f actually resembles Earth or not, this discovery provides more information on the incredible variety of planetary systems to be found even in our little corner of the galaxy.

“The diversity of these exoplanets is one of the most exciting things about the field,” Kane said. “We’re trying to understand how common our solar system is, and the more diversity we see, the more it helps us to understand what the answer to that question really is.”

The SETI Institute’s Allen Telescope Array has surveyed the Kepler-186 system for any potential signals but so far none has been detected. Further observations are planned.

“Kepler-186f is special because we already know that a planet of its size and distance is capable of supporting life.”
– Elisa Quintana, research scientist, SETI Institute

The team’s paper, “An Earth-sized Planet in the Habitable Zone of a Cool Star” by Elisa V. Quintana et al., will be published in the April 18 issue of Science.

Learn more about the Kepler mission here, and read more about this discovery in NASA’s news release here and on the W.M. Keck website here.

Watch some video excerpts of team interviews and data renderings below:

Also, you can download the slides used in the NASA teleconference here.

Sources: San Francisco State University, Gemini Observatory, W.M. Keck Observatory, and SETI news releases

Inside the Drake Equation: A Chat with Frank Drake

The Drake Equation.

This interview with Frank Drake — sometimes called the Father of the Search for Extraterrestrial Intelligence – was recorded in 2012 but not released until now to celebrate the beginning of the 30th year of the SETI Institute. As interviewer Andrew Fraknoi says, “I don’t think anyone had a conversation like this that was recorded with Galileo or William Herschel or Edwin Hubble, but I get to do it with Frank Drake!”

This is a great conversation that alternates between Drake’s current work with SETI and the history of his work that led to the famous Drake Equation. Fraknoi and Drake have an interesting exchange about the value of N, which is the number of civilizations in The Milky Way Galaxy whose electromagnetic emissions would be detectable.

It was recorded in June 2012 at an event called SETICon, which featured a series of talks, panels, and events featuring scientists, authors, futurists, and film-makers.

Fraknoi is a professor of astronomy and also works with the Astronomical Society of the Pacific and they have made available a written history of Frank Drake and his equation.

Novel Strategy May Help Target Extraterrestrial Intelligent Life

Photo: Mike Agliolo/Corbis

Discovering life beyond Earth might just be the holy grail of science. And even though we have yet to find evidence for little green men or blobs of bacteria, astronomers continue to search for elusive signs of life.

A novel strategy may help astronomers better target extraterrestrial intelligent life. Dr. Michael Gillon, of the University of Liege in Belgium, proposes an approach that would monitor the regions of nearby stars to search for interstellar communication devices.

The most common method in the search for extraterrestrial intelligence (abbreviated as SETI) is the use of giant radio dishes to scan the stars, listening for possible faint signals coming from distant civilizations.

While the SETI institute has been hard at work since 1959 we haven’t chanced upon a signal yet. But that doesn’t mean we’re alone or that we should stop looking.

Even without a confirmed extraterrestrial signal, most astronomers would argue that recent discoveries have strongly reinforced the hypothesis that extraterrestrial life may just be abundant in the Universe. With the help of the Kepler Space Telescope we have learned that planets are plentiful throughout the Milky Way. With most stars harboring at least one planet, it’s conceivable that a few of those planets will have the right conditions for life.

So why haven’t we detected extraterrestrial intelligent life? Why do we have this glaring Fermi Paradox — the apparent contradiction between the high probability of extraterrestrial civilizations’ existence and the lack of contact with such civilizations?

One hypotheses to explain the famous Fermi Paradox is that self-replicating probes could have explored the whole Galaxy, including our Solar System, but we just haven’t detected them yet. A self-replicating probe is one sent to a nearby planetary system where it would mine raw materials to create a replica of itself that would then head towards other nearby systems, continuing to replicate itself along the way.

While our own technological civilization is less than two hundred years old, we have already sent robotic probes to a large number of bodies in our Solar System and beyond. Our furthest-reaching probe, Voyager 1, just made it to interstellar space. But it took it over 40 years.

“We are still far from being able to build an actual self-replicating interstellar spaceship, but only because our technology is not mature enough, and not because of an obvious physical limitation,” Dr. Gillon told Universe Today.

While we cannot currently send self-replicating probes to the nearest stars in a reasonable amount of time, nothing excludes this as a reachable future project, or a project already completed by extraterrestrial intelligent life.

This study further proposes that probes from neighboring stellar systems could use the stars they orbit as gravitational lenses to communicate efficiently with each other.

The coordination of probes to explore the Galaxy would be very inefficient unless they had the ability to directly communicate with one another. The vastness and structure of the Milky Way makes this seemingly impossible. By the time a signal reached a very distant star it would be highly diluted.

However, any star is massive enough to bend and amplify light. This process, gravitational lensing, is extremely powerful. “It means that the Sun (and any other star) is an antenna much more powerful than we could ever build,” says Dr. Gillon.

Based on this method, interstellar communication devices will exist along the line that connects one star to another. We now know exactly where to look, and even where to send messages.

Could this novel idea provide a new mission for SETI?

“A negative result wouldn’t tell us very much,” explains Dr. Gillon. “But a positive result would represent one of the most important discoveries of all time.”

The paper has been accepted for publication in Acta Astronautica and is available for download here.

A Tale of a Lost Moon: Hubble Spies Neptune’s Moons and Its Rings

Neptune's system of moons and rings visualized. Credit: SETI

“That’s no moon…”

-B. Kenobi

But in this case, it is… a lost moon of Neptune not seen since its discovery in the late 1980’s.

A new announcement from the 45th Meeting of the Division for Planetary Sciences of the American Astronomical Society being held this week in Denver, Colorado revealed the recovery of a moon of Neptune that was only briefly glimpsed during the 1989 flyby of Voyager 2.

The re-discovery Naiad, the innermost moon of Neptune, was done by applying new processing techniques to archival Hubble images and was announced today by Mark Showalter of the SETI institute.

Collaborators on the project included Robert French, also from the SETI Institute, Dr. Imke de Pater of UC Berkeley, and Dr. Jack Lissauer of the NASA Ames Research Center.

The findings were a tour-de-force of new techniques applied to old imagery, and combined the ground-based 10 meter Keck telescope in Hawaii as well as Hubble imagery stretching back to December 2004.

The chief difficulty in recovering the diminutive moon was its relative faintness and proximity to the “dazzling” disk of Neptune. At roughly 100 kilometres in diameter and an apparent magnitude of +23.9, Naiad is over a million times fainter than +8th magnitude Neptune. It’s also the innermost of Neptune’s 14 known moons, and orbits once every 7 hours just 23,500 kilometres above the planet’s cloud tops. Neptune itself is about 49,000 kilometres in diameter, and only appears 2.3” in size from Earth. From our Earthly vantage point, Naiad only strays about arc second from the disk of Neptune, a tiny separation.

“Naiad has been an elusive target ever since Voyager left the Neptune system,” Showalter said in a recent SETI Institute press release. Voyager 2 has, to date, been the only mission to explore Uranus and Neptune.

To catch sight of the elusive inner moon, Showalter and team applied new analyzing techniques which filtered for glare and image artifacts that tend to “spill over” from behind the artificially occulted disk of Neptune.

Naiad
Naiad as seen from Voyager 2. (Credit: NASA/JPL).

Other moons, such as Galatea and Thalassa — which were also discovered during the 1989 Voyager 2 flyby — are also seen in the new images. In fact, the technique was also used to uncover the as of yet unnamed moon of Neptune, S/2004 N1 which was revealed earlier this year.

Naiad is named after the band of nymphs in Greek mythology who inhabited freshwater streams and ponds. The Naiads differed from the saltwater-loving Nereids of mythology fame, after which another moon of Neptune discovered by Gerard Kuiper in 1949 was named.

It’s also intriguing to note that Naiad was discovered in a significantly different position in its orbit than expected. Clearly, its motion is complex due to its interactions with Neptune’s other moons.

“We don’t quite have enough observations to establish a refined orbit,” Mr. Showalter told Universe Today, noting that there may still be some tantalizing clues waiting to be uncovered from the data.

I know the burning question you have, and we had as well during the initial announcement today. Is it REALLY Naiad, or another unknown moon? Showalter notes that this possibility is unlikely, as both objects seen in the Hubble and Voyager data are the same brightness and moving in the same orbit. To invoke Occam’s razor, the simplest solution— that both sightings are one in the same object —is the most likely.

“Naiad is well inside Neptune’s Roche Limit, like many moons in the solar system,” Mr. Showalter also told Universe Today. Naiad is also well below synchronous orbit, and is likely subject to tidal deceleration and may one day become a shiny new ring about the planet.

The labeled ring arcs of Neptune as seen in newly processed data. The image spans 26 exposures combined into a equivalent 95 minute exposure, and the ring trace and an image of the occulted planet Neptune is added for reference. (Credit: M. Showalter/SETI Institute).
The labeled ring arcs of Neptune as seen in newly processed data. The image spans 26 exposures combined into an equivalent 95 minute exposure. The ring trace and an image of the occulted planet Neptune is added for reference. (Credit: M. Showalter/SETI Institute).

And speaking of which, the tenuous rings of Neptune have also evolved noticeably since the 1989 Voyager flyby. First discovered from the ESO La Silla Observatory in 1984, data using the new techniques show that the knotted ring segments named the Adams and Le Verrier have been fading noticeably.

“In a decade or two, we may see an ‘arc-less’ ring,” Showalter noted during today’s Division for Planetary Sciences press conference. The two ring segments observed are named after Urbain Le Verrier and John Couch Adams, who both calculated the position of Neptune due to orbital perturbations of the position of Uranus. Le Verrier beat Adams to the punch, and Neptune was first sighted from the Berlin Observatory on the night of September 23rd, 1846. Observers of the day were lucky that both planets had undergone a close passage just decades prior, or Neptune may have gone unnoticed for considerably longer.

The rings of Neptune as seen from Voyager 2 during the 1989 flyby. (Credit: NASA/JPL).
The rings of Neptune as seen from Voyager 2 during the 1989 flyby. (Credit: NASA/JPL).

Neptune has completed just over one 164.8 year orbit since its discovery. It also just passed opposition this summer, and is currently a fine telescopic object in the constellation Aquarius.

Unfortunately, there aren’t any plans for a dedicated Neptune mission in the future. New Horizons will cross the orbit of Neptune in August 2014, though it’s headed in the direction of Pluto, which is currently in northern Sagittarius. New Horizons was launched in early 2006, which gives you some idea of just how long a “Neptune Orbiter” would take to reach the outermost ice giant, given today’s technology.

This represents the first time that Naiad has been imaged from the vicinity of Earth, and demonstrates a new processing technique capable of revealing new objects in old Hubble data.

“We keep discovering new ways to push the limit of what information can be gleaned from Hubble’s vast collection of planetary images,” Showalter said in the SETI press release.

Congrats to Showalter and team on the exciting recovery… what other moons, both old and new, lurk in the archives waiting to be uncovered?

– Read today’s SETI Institute press release on the recovery of Naiad.

-Be sure to follow all the action at the 45th DPS conference in Denver this week!