It's been 13 years since NASA's Opportunity rover is exploring Mars. In your oppinion what is it's most important discovery to date? Is it our most succesful Mars rover? Will the next Mars rover (planned for touchdown on Mars surface in 2020) have to chance to achieve even more? What would you personally like to see as it's scientific payload?
Andrew Rader (SpaceX engineer, MIT PhD, author)

Perhaps the greatest discovery of the Spirit and Opportunity rovers has been to study the water cycle on Mars and yield clues as to how ice and frost moves about the planet with seasons and weather, although it would be hard to argue that Opportunity's greatest achievement isn't its marathon longevity. Curiosity and the 2020 Rover are much more capable than Opportunity so should interact more with the planet and (presuming a long mission) may even eventually travel farther. I think the most important experiments going forward are related to the search for water and life on Mars, and starting to conduct experiments on use and conversion of local resources like the production of methane, oxygen, and liquid water.

Nancy Atkinson (Senior Editor for Universe Today, Host of the NASA Lunar Science Institute podcast & a NASA/JPL Solar System Ambassador)

I think its interesting that basically everywhere Curiosity has traveled, it is finding evidence of past water. From the rounded pebbles that were worn by flowing water to the mudstone and sandstone features, to the layered rock formations that could only be laid down in large amounts of water, it appears that Gale Crater was at one time filled with water. And that's intriguing because we know on Earth, everywhere there is water, there is life. Curiosity has been finding these features and potentially habitable environments almost since it landed, so the choice of Gale Crater as the landing site appears to have been the perfect place to explore!

I'm really looking forward to the Mars 2020 rover, especially how it should be able to test ways for future human explorers to use the resources available on Mars to ‘live off the land.’ Also, it should help us understand the hazards posed by Martian dust and demonstrating technologies to process carbon dioxide from the atmosphere to produce oxygen, which could be used for the production of fuel. 

Antonio Paris (Astronaut Candidate, Astronomy Professor, Planetary Scientist, Space Science Author)

The Mars rover Opportunity has made many groundbreaking achievements in the exploration on Mars. Its greatest achievement, in my opinion, does categorically fall into science or technology. I believe that Opportunity’s greatest achievement is that it served as an “extension” to the human eye, thus allowing us to explore a far distant world where humans are still decades away from making landfall. Additionally, none of the rovers on Mars are more successfully than the other. Each robotic mission to Mars had a specific purpose and it was their cumulative discoveries that have made the exploration of Mars a success thus far. Moving forward, there is an assortment of Mars rovers that will one day take the helm for Opportunity. As technology continues to improve, I sure hope a HD live cam makes it way into the next rover’s payload!

How to win Nancy Atkinson’s book

10 people have the chance to win Nancy Atkinson's book "The Incredible Stories From Space: A Behind the Scenes Look at the Missions Changing Our View of the Cosmos".

For your chance to win a free copy of the book you need to enter a giveaway competition at Goodreads -

Competition ends on Jan 20, 2017

Farewell Rosetta!

rosetta-im-all_xlFew weeks ago Rosetta probe deliberately crashed into comet 67P/Czuriumow-Gierasimienko ending it’s 12 years mission. What did we learn from this mission? What is the most interesting discovery that came from landing on a comet for the first time in history?

Nancy Atkinson (Senior Editor for Universe Today, Host of the NASA Lunar Science Institute podcast & a NASA/JPL Solar System Ambassador)


The Rosetta mission has been an absolute joy to witness, with its great success, surprising findings, and unique public outreach from the team that included cute videos and cartoons. The images have been nothing short of stunning and being able to see a comet close-up like this is just eye-candy: views of cliffs, rockslides and boulders, spraying jets and of course the duck-shaped comet itself.

Some of the discoveries are really exciting, such as finding amino acids that are the building blocks of life on the comet; finding out Comet 67P sings, and finding molecular oxygen. One of the most surprising findings is that the chemical signature of the comet’s water is nothing like what we have on Earth, which contradicts the long-standing theory that comets pummeling Earth supplied our planet with water. Don’t fret the mission is over, as scientists will be studying Rosetta’s observations for years to come, so we’ll definitely be hearing from Rosetta again.

Andrew Rader (SpaceX engineer, MIT PhD, author)


This mission was important for a lot of reasons. From a scientific perspective, it tells us about an object from the far reaches of the Kuiper Belt and probably as old as the formation of the solar system. What are it’s characteristics and composition? Could comets have brought water to Earth, or even the building blocks for life?

From a practical perspective, we learned that we can rendezvous with and land on a type of object that might one day pose a dire threat to our planet. Alternatively, such a comet could potentially be useful in providing raw materials while we hitch a ride far out into space.

Antonio Paris (Astronaut Candidate, Astronomy Professor, Planetary Scientist, Space Science Author)


Hundreds of years from now, when our ancestors look back at the early years of space exploration, there are no doubts the Rosetta mission will be among the top list of achievements. The rendezvous with comet 67P, which is an achievement of its own, will harness scientific data for generations. Recent mission data, however, has already re-drawn the cometary landscape and astronomers have been left to re-write textbooks when it comes to comets. For example, we have learned 67P interacts with the solar wind, a significant amount of water has been discovered on the comet, and that perhaps comets, at least in this case 67P, was not responsible for bringing water to Earth billions of years ago. We have a lot of work ahead of us and the data from Rosetta will take years to study – an exciting time for astronomers!

Ciro Villa (technologist, application developer, STEM communicator)


Being able for the first time in the history of mankind to approach, orbit and land on a 4 kilometers wide chunk of rock and ice coming from the fringe of our solar system, located at about half a billion kilometers away from us and traveling around the Sun at a velocity of about 135,000 kilometers per hour, was a tremendous feat of human engineering in it of itself. This is exactly what the Rosetta mission has been able achieve during its groundbreaking mission.

Indeed, a vast amount of science has been done by Rosetta during the 786 days of its mission spent around the comet operating in a prohibitive and unforgiving environment. We have learned a great deal more than we used to know about the complexity of the composition of comets such as 67P and we have learned how difficult it is to perform with extreme precision the sort of mission activities that the Rosetta mission team could do and how small the margin of error is for space missions in general and for something as complex as the Rosetta mission.

Despite problems experienced during the touchdown of the Phoebe lander, the Rosetta mission’s team was still able collect a vast trove of scientific data that will be analyzed for decades to come, as well as being able to accomplish a series of important scientific milestones. For instance, among the most outstanding discoveries was that of the presence of a peculiar “songlike” magnetic field probably caused by the solar wind.

Additionally, the discovery of the presence of various molecules originating from the comet ‘s nucleus as well as the presence of water of a different composition of that present here on Earth, were among other findings that have made an impact within the scientific community. All in all, the mission, culminating with the planned crash of Rosetta on the surface of the comet, was a definite success and as a provider of lesson learned, an important precursor for other future missions to small bodies such as asteroid and comets that would have tremendously important value and implications for the future of mankind.

The Force Awakens

We were waiting for another part of Star Wars trilogy for 10 years. How was it? How different was it from previous movies? With movies looking so far in the future can we even discuss its scientific accuracy?
Paul Carr (Space Systems engineer at NASA, podcaster, blogger, investigator)

I wasn’t a fan of the prequels, but I found The Force Awakens to be fun and entertaining. I’ve never taken Star Wars very seriously, though. To me, it’s more Space Opera than Science Fiction (not that there’s ANYTHING wrong with that…). It wasn’t that much different for me, ignoring the prequels. I thought it was better written than the Lucas directed films, but that was not a high bar. there also seems to be some borrowing of thematic material from Harry Potter, which is not surprising, given that an entire generation was tuned into that story and its themes. Kylo Ren even looked a bit Snape-like to me, even though his motivations were quite different from Snape’s. For me, though, Kylo doesn’t touch “The Operative” in Serenity as a Space Opera Bad Buy With A Sword, but that is to be expected for a film franchise like Star Wars that finds much of its audience in kids – bad guys need to be not too evil. Scientific accuracy is not a strength of this genre. Hard science fiction that strives for at least plausibility is rare, although it seems to be making a comeback, with films like “The Martian” and “Ex Machina”. Most of what we see depicted in Star Wars and similar films can always be waved away with the notion that it involves physics not yet known to humanity., and that is in itself at least somewhat plausible. One thing we see depicted in the latest film is the salvaging of a once sophisticated technology for spare parts – this appears to be a galactic civilization that is in decline in some sense, although the people there have at least some idea of how their technology works. To me, that’s an interesting theme, and would like to see it explored further. Has war destroyed science, or advanced it?

Nancy Atkinson (Senior Editor for Universe Today, Host of the NASA Lunar Science Institute podcast & a NASA/JPL Solar System Ambassador)

I really enjoyed “The Force Awakens,” as it seemed to be a throwback to the original three movies in the Star Wars saga. I’m actually not a big fan of the second trilogy set. Of course, it was wonderful to see the “old” stars again (and yes, they’ve gotten old), and the new cast was great. But it also crossed my mind while watching it that this new movie was basically the same plot as before: a small band of resistance fighters goes up against the “Dark Side’ evil superpower. So, I’m kind of hoping the remaining two movies will come up with some usual twist or turn in the plot …. as long as there are still spaceships and robots, though!

Andrew Rader (SpaceX engineer, MIT PhD, author)

Quite a good addition to the Star Wars Universe! Star Wars actually takes place in the past, but obviously the general level of technology is quite a bit more advanced than our own. Since any sufficiently advanced technology would seem to us to be magic, I’m not sure it makes sense to focus on individual technologies represented. I can accept faster than light travel, ridiculously advanced power sources, the force, or tie fighters that fly through planetary atmospheres with no aerodynamic flight surfaces. So I’ll give these a pass. There were, however, a few inconsistencies that bothered me. I’m not sure they captured the true scale of an organization that would span a galaxy. Both the Republic and First Order seemed to live on a small scale – only a few planets, a small number of ships, etc., which isn’t consistent with the scale of the Star Wars galaxy of billions of stars. Additionally, the planet-destroying weapon and actual destruction of the planet was viewed in essentially real time by people on another planet. To be anywhere near possible, both the space station which initiated the attack, and the planet witnessing the attack would all have to be in the same solar system (based on the speed of light). This didn’t seem to be the case. But apart from a few small but significant scientific inconsistencies, it was an enjoyable movie for sure.

Robert Novella (co-founder and vice-president of New England Skeptical Society, co-host of Skeptics’ Guide to the Universe)

I thoroughly enjoyed the New Star Wars movie. It really was a perfect storm of fun for me. We had about 30 people with us and the theater had literally, the best damn movie seats I’d ever seen. Many of us had costumes as well and SGU brought our new light sabers of course (bladeless unfortunately). The movie itself truly brought back the fun and excitement I remember from that very first Star Wars movie so long ago. The Force Awakens was vastly different from the epically disappointing prequel movies. The acting, writing, and character interactions were all far superior. There were plenty of wonderful practical FX and just the right amount of CG where it was needed.  Compared to the original 3 movies however, one can make a compelling argument that it was too similar to A New Hope…..our hero grows up on a desert planet, a cute Droid with a secret message, a huge planet-killing machine etc. Scientific accuracy is always open to discussion, especially when the technology is based on actual physical devices. In these types of science-fiction movies, it’s always polite to allow for a few “Gimmies” for the sake of the plot like faster than light travel, the Force etc (as long as they are used in a consistent manner).  In the case of The Force Awakens, the lamest bit of science that isn’t a gimmie is the StarKiller base. I was ok with many aspects of this device except how it appears to fuel or charge its weapon. It is clearly shown sucking in an entire star. That was complete over-kill. That amount of mass/energy in such a small place would create a neutron star or a black hole. How would the base survive such an object in its belly? Why not absorb just a portion of the star?  The bottom line though is that they made a very enjoyable movie and have revived one of the most iconic movies series of all time. I really can’t wait for the next installments.


Lots have happened in 2015 – it was definitively rich year in astronomy. I asked our panelists how would they summarize year 2015? How was it for them personally?

Andrew Rader (SpaceX engineer, MIT PhD, author)

2015 was overall a great year for space – first successful recovery of the Falcon 9 with the potential to change spaceflight forever. It was also a great year for robotic spaceflight: with our first close-up images of Pluto and Charon, and the Dawn spacecraft entering orbit around Ceres using an ion engine, you might call 2015 the year of the Dwarf Planets. Here’s to a productive 2016 and times ahead!

Antonio Paris (Astronaut Candidate, Astronomy Professor, Planetary Scientist, Space Science Author)

2015 was a very busy year for me – since I spent half of it trying to find an answer to the famous 1977 Wow! signal. After publishing my latest paper regarding the signal, which centered on a pair of comets, the attention from the media quickly catapulted me into the politics of science. For the most part, many scientists found my hypothesis intriguing and only further observations of these comets will seal the deal. Unfortunately, there is politics in science and I learned that a few scientists in the community, especially those working closely with SETI-like entities, would prefer that the Wow signal remains a mystery. Science requires money and the funding dries up rather quickly of the public loses interest.


Nancy Atkinson (Senior Editor for Universe Today, Host of the NASA Lunar Science Institute podcast & a NASA/JPL Solar System Ambassador)

2015 was a busy year in planetary exploration, with Dawn arriving at Ceres and New Horizons zooming past Pluto. This gives us a close look at two planetary bodies that until now we’ve only had pixelated views. Who would have thought we’d see a conical mountain and epsom salts on Ceres and cryovolcanoes and a ‘heart’ on Pluto? Plus Rosetta and Philae provided some drama and closeup views of a comet.  The mystery of the star KIC 8462852 definitely is an intriguing story, one that will be of interest in the year to come as well, I’m sure.  And spacecraft like Kepler, Hubble, Spitzer and others continue to show us the wonders of the Universe.  Personally, 2015 was a big year for me, as I signed a contract to write a book about robotic space exploration missions. I wrote about it here: Thank you to all the space and astronomy enthusiasts around the world who make my job very rewarding!

What to expect from 2016?

December is a month in which we usually summarize this ending year and decide how good it was. Let’s leave that for later and look a bit into the future. What should we expect from the year 2016.

Antonio Paris (Astronaut Candidate, Astronomy Professor, Planetary Scientist, Space Science Author)

I am personally looking forward to developments in the Orion Program and Journey to Mars. Speaking of the latter, I am in the process of writing my third book, which will center on Generation: Mars. I am hopeful, moreover, that the commercial space industry will continue to make great strive in space exploration with special emphasis on Mars, asteroids, and Pluto.

Nancy Atkinson (Senior Editor for Universe Today, Host of the NASA Lunar Science Institute podcast & a NASA/JPL Solar System Ambassador)

I’m looking forward to seeing more images and data of the Pluto system coming back from New Horizons, as well as more great images and science from the two Mars rovers (Curiosity and Opportunity) and the Mars Orbiters (MAVEN, MRO, Mars Express, Odyssey,  and India’s MOM). ESA’s ExoMars Trace Gas Orbiter is scheduled to arrive in orbit at the Red Planet in March. NASA’s InSight lander was scheduled to land on Mars in September to study the planet’s interior, but the mission has been postponed at least 2 years due to a problem with one of the instruments. Also in September, the Rosetta mission will come to a crashing end with a controlled impact on the surface of comet Churyumov-Gersimenko, and the OSIRIS-Rex mission is scheduled to launch on its mission to asteroid Bennu. Of course Cassini will keep going until 2017 and it just keeps wowing us with images of Saturn and its rings and moons. The big news for 2016 in planetary exploration is that Juno will arrive at Jupiter in July. It will map the interior of the giant world as well as studying the planet’s magnetic and gravity fields and map the abundance of water vapor in the planet’s atmosphere. It also will provide the first images of the previously unexplored poles of Jupiter. 2016 should be a great year in planetary exploration!

Pamela Gay (assistant research professor at Southern Illinois University, writer, co-host of Astronomy Cast)

My gut says it will come with more budget issues, more sexual harassment and discrimination holding back women and minorities, and commercial space advancing while science for the sake of science sees the same old same old. Here’s to hoping I’m wrong on everything but commercial space!

James Webb Space Telescope

If everything goes as planned, James Webb Space Telescope will go in space and become operational in the end of 2018. It’s sometimes regarded as a successor to Hubble Space Telescope. If you could decide, where would you point it’s “eye” for a first look?
Nicole Gugliucci (“Noisy astronomer”, blogger, educator, post-doc)

I’d point it at a protoplanetary disk to see what exoplanets look like in formation! I was blown away when astronomers using ALMA (Atacama Large Millimeter/Submillimeter Array) got this image of one (, so I can’t wait to see what JWST reveals in the infrared for systems like this.

Nancy Atkinson (Senior Editor for Universe Today, Host of the NASA Lunar Science Institute podcast & a NASA/JPL Solar System Ambassador)

I’m looking forward to seeing how far in space and time the Webb can look.  Will it see the very first star formation in the Universe? Will it provide a glimpse at what the earliest galaxies looked like? Will we be able to observe the formation of the first planetary systems? Will we see back even farther to moments after the Big Bang? Will JWST give us more information about the Cosmic Dark Ages?  It is expected to be able to see objects between 10 to 100 times fainter than Hubble can see, so I’m hoping its ‘first light’ will test the limits of how far JWST can see.

Andrew Rader (SpaceX engineer, MIT PhD, author)

James Webb is perfect for looking at planetary formation and early galaxies from the birth of the Universe. It’s the kind of science where it’s hard to predict exactly what we’ll find, but that’s the point! Whatever it is, it’s sure to be fascinating and improve our understanding of the cosmos and our place in it.  I hope it helps shed more light (infrared of course!) on planet formation and how typical our solar system is likely to be.

Antonio Paris (Astronaut Candidate, Astronomy Professor, Planetary Scientist, Space Science Author)

Why not use the James Webb Telescope to search for alien planets? It is alleged by conspiracy claptrap that the Grays, an alleged species of extraterrestrials, are from Zeta Reticuli, which is a wide binary star system in the southern constellation of Reticulum. From the southern hemisphere the pair can be observed as a naked eye double star in very dark skies. Based upon parallax measurements, Zeta Reticuli is located at a distance of about 39 light-years from the Earth. Both stars are solar analogs and share comparable characteristics with the Sun. Although the kinematics of these stars imply that they belong to a population of older stars, the properties of their stellar chromospheres indicate they are only about 2 billion years old. On September 20, 1996, astronomers reported a provisional discovery of a hot Jupiter around Zeta-2, but the discovery was briefly retracted as the signal was caused by pulsations of the star. In 2002, moreover, Zeta-1 was scanned at an infrared wavelength of 25 μm, but no extrasolar planets were found.  The James Webb could possibly detect extrasolar planets, if any, around Zeta Reticuli and perhaps close the books on the Grays for good.

Fraser Cain (publisher at, co-host of Astronomy Cast)

James Webb should be able to look right back the edge of the observable Universe and see some of the earliest structures forming. It’ll be amazing to finally get a picture of what the Universe looked like so long ago, when everything was much closer together. How did those early galaxies form so quickly? When did the first supermassive black holes form? I can’t wait to find out the answers.

Hello, are you there?

Search for extraterrestial intelligence has been our interest since the begining of 1900s. Around that time we started broadcasting radio signals. We’ll find an exoplanet with life on its surface any minute now (or year or decade). What song, tv series and movie should we broadcast in space to let know our alien friends what a lovely and peaceful civilization we surely are?
Andrew Rader (SpaceX engineer, MIT PhD, author)

Movie and TV series, if we want to paint a good impression, I’d go for the Contact and the original Cosmos with Carl Sagan. These demonstrate that we’re interested in bettering ourselves, understand how we fit into the Universe, and are eager to learn what’s out there.

I’m not sure how an extraterrestrial would interpret music, but I’m guessing something timeless like a great classical piece would put our best foot forward. Maybe something uplifting like Beethoven’s 9th symphony (4th movement, ode to joy)?

Antonio Paris (Astronaut Candidate, Astronomy Professor, Planetary Scientist, Space Science Author)

Ever since the first radio signal was transmitted on Earth, an expanding sphere of radio signals has been traveling outward into space from the earth. The first of early radio transmissions were short-range experiments that used simple clicks and interrupts to show transmission of information in the 1890s. In 1900, Reginald Fessenden made the first — though exceptionally faint — voice transmission over the airwaves. The next year, in 1901, saw a step up in power as Guglielmo Marconi made the first ever transatlantic radio broadcast. Since then, at a distance of about light-years away from earth, our very first radio broadcasts are beginning to arrive. While it’s fascinating to envision how far our radio signals have traveled into space, it’s improbable that a technologically advanced extraterrestrial civilization would be able to receive, listen, or understand Marconi’s message.

Due to the inverse square law, radio signals transmitted into space degrade over distance. When Marconi’s signal left earth and transmitted into space in 1901, it spread out in a wave similar to dropping a stone in a lake. The waves diffused or spread out over distance due to the exponentially larger area it had to encompass. In short, because of this inverse square law, all radio signals from Earth become indistinguishable from background noise after a few light-years. However, if we could send a microwave signal for interstellar communication, at a range from 1 GHz to 10 GHz, it is possible that an alien species could receive the signal. This is, of course, assuming that such species has the technology to detect the signal, and, more importantly, are able to interpret the signal as extraterrestrial on their part.

If for some offbeat reason I was the astronomer responsible for sending such radio signal, I would send the the piano version of Ave Maria by Franz Schubert. This is, in my opinion, one of the most beautiful and peaceful sounds we could emit into deep space. For a TV series, I would transmit Cosmoswith Carl Sagan. An intelligent extraterrestrial civilization watching Cosmos would, notionally, assume that the civilization transmitting the TV signal has a rudimentary understanding of the Universe. Lastly, for a movie, I would transmit without a doubt Independence Day. Just in case the aliens decide to invade … Independence Day should serve as an essential warning to our galactic neighbors: we will kick their ass.

Nancy Atkinson (Senior Editor for Universe Today, Host of the NASA Lunar Science Institute podcast & a NASA/JPL Solar System Ambassador)

I love the song “Trip The Light”, which was used in a “Where The Hell is Matt” video (the crazy dancing guy) in 2012. I posted it on my website ( ) and wrote: “I hope when future generations look back at this time in history, or if an alien civilization ever found evidence of life on Earth, this is what they’d see. All anyone ever really wants is to be happy, and sometimes dancing is the only way to express it.” The song and video also expresses a one-ness across our world that we should aspire to truly make a reality. One verse says:
Remember we’re lost together
Remember we’re the same
We hold the burning rhythm in our hearts
We hold the flame
I don’t watch much TV, so it is hard for me to pick a TV series! The easy answer would be easy to say one of the “Star Trek” series, probably the “Voyager” series because it portrayed a widely diverse crew that had to deal with lots of adversity, and they met up with lots of different alien species (OK, that actually describes ALL of the Star Trek series….)!
As far as a movie, I’m going to go with my favorite movie of all time, “Love Actually.” It shows humanity, warts and all, but despite our failings, we can still manage to figure out how to get along.


We sometimes dream about turning other worlds into habitable ones. Is terraforming worth the try giving the resources needed? Is Mars the obvious choice or should we choose a different world?

Robert Novella (co-founder and vice-president of New England Skeptical Society, co-host of Skeptics’ Guide to the Universe)

I think Terraforming is a no brainer if for no other reason than to have humanity on more than one planet. A worst-case scenario then, like an asteroid strike, would not have to mean the extinction of all life on Earth. It’s definitely worth the effort but the resources required are staggering. We have the technology now to begin the process but it would be just too expensive. The good news is that the resources required will become increasingly less onerous as technology improves.

Ultimately I think we could use a form of molecular nanotechnology to not only perform most of the work but also complete it in a time frame on the scale of decades or less instead of centuries or even millennia. All or most of the raw material required may even already be on the planet. Mars for example already has what we’d need to not not only create the nanomachines but also the oxygen, nitrogen, and carbon dioxide gas to produce a breathable and comfortable atmospheric pressure.

The obvious choices for terraforming in our solar system are Venus and Mars. The low gravity of moons make atmospheric retention an issue. Both these planets are much better options but for every good reason why, there’s also a downside. For example, Venus has 90% of earth’s gravity but its day is 116 earth-days. A day on Mars is very close to earth’s but it’s gravity is only 38%.

I’d have to choose Mars since the energy required to cool Venus and speed its rotation far exceeds what it would take to warm Mars and thicken its atmosphere. The thicker atmosphere would also likely block enough cosmic rays to make that a tolerable problem.

Fraser Cain (publisher at, co-host of Astronomy Cast)

We’ve actually done a whole series on terraforming as part of the Guide to Space video series we publish on YouTube. We’ve talked about terraforming Mars, Venus, the Moon, Jupiter and even the Sun and black holes (I don’t recommend those last two).

Mars is an interesting target, but one big concern is its low gravity. Can humans survive long term in 30% gravity? Another huge problem is the lack of a geomagnetic field, which would protect future Martians from solar and cosmic radiation.

Although it’s probably harder, Venus sounds like a better target because of its similar size and gravity to Earth. There would be a lot of work to get the dense carbon dioxide out of the air and spin up the planet’s rotation, but the cloud tops of Venus are surprisingly habitable right now. At the right altitude, the temperature and pressure are the same as Earth and our breathable air is a lifting gas. So, future colonists could live in floating cities on Bespin… I mean Venus.

Andrew Rader (SpaceX engineer, MIT PhD, author)

Apart from traveling to another star, I think terraforming is the long-term purpose of branching out into space. Mars is certainly the most suitable because it has all the elements in place, and it’s essentially returning the planet to the way we think it once was. However, it’s probably a more difficult task than people realize, not because of the science behind it, but because of the magnitude of the engineering challenge. It’s easy enough to melt a bit of CO2 ice on Mars and warm up the planet a fraction of a degree, but melting all the polar ice caps to raise the pressure and create a greenhouse effect on Mars is a daunting task. It’s also unclear if melting all the ice would be enough to make Mars a suitable planet to walk around without a space suit (and eventually without a respirator). More intervention may be required.

We may find a simple solution like some kind of self-replicating special microbes or nanobots that we could simply introduce and they would do the rest, but it’s not certain and that also increases other potential dangers like an unstoppable runaway effect. There was even a proposal to seed the Venusian clouds with microbes which could transform Venus into a habitable place – but on Venus, I think we might be stuck in the clouds for a while (which are suitable for floating habitats now). I think it’ll be a long time before we’re truly able to terraform a planet, but that should stop us from experimenting with the concept now. Moreover, there are alternatives to full terraforming. Even partially terraforming Mars by raising the temperature and pressure would be a huge benefit to exploration and settlement, and we can envision enclosed areas of the planet like large dome structures which is effectively terraforming a small section of the planet (AKA “paraterraforming”). If I had to guess, I’d wager Mars will be fully terraformed within the next 1000 years, provided humanity lasts that long.

Nancy Atkinson (Senior Editor for Universe Today, Host of the NASA Lunar Science Institute podcast & a NASA/JPL Solar System Ambassador)

Mars is probably the obvious choice for doing any terraforming (Venus is too hot and crushing while Europa or any other moons of Jupiter or Saturn are too cold) But it would be an incredible proposition to even attempt to try it, and the technology to accomplish such a feat is likely decades away, if not centuries or more. Plus the process itself would likely take hundreds of years to accomplish. I see terraforming as an “emergency” procedure if Earth was somehow becoming inhabitable. Hopefully we won’t have to think about that as a possibility for quite some time!

While Mars has the basic ingredients to do terraforming (water, nitrogen and carbon and oxygen in the form of CO2) there are a few problems to overcome with terraforming Mars. One is that Mars has only trace amounts of atmospheric CO2, and unless there is more CO2 locked up in the polar ice caps than currently estimated, it would be difficult to create as much CO2 as would be needed. You’d have to have huge factories spewing out CO2 to create a greenhouse effect on Mars. This would create a nice thick breathable atmosphere that would also warm up the planet.
The other problem is that Mars lost its magnetic field millennia ago due to a cooling down of its core and mantle. A magnetic field is necessary to shield the planet from the Solar Wind, which otherwise blasts away the atmosphere and any liquid water that might be there. Without a magnetic field, creating a thicker atmosphere or oceans would be an effort in futility.

Nicole Gugliucci (“Noisy astronomer”, blogger, educator, post-doc)

Terraforming a whole planet seems like a huge task that may not have the most gain. After all, it would take quite a lot of resources to build up Mars’ atmosphere, for example, and then to keep replenishing it without a planet-wide protective magnetic field. Unless there is a compelling reason to develop huge tracts of land, I see colonization starting in domes that would connect around a planet like Mars.

Mars seems like an obvious planetary choice for reasons of gravity (less than Earth but potentially still adaptable) and the familiar day-night cycle. One idea I particularly like is to use a hollowed out asteroid as a floating and rotating (to simulate gravity) space colony, but given that so many asteroids may be no more than rubble piles, that may not be feasible at all.

Antonio Paris (Astronaut Candidate, Astronomy Professor, Planetary Scientist, Space Science Author)

For decades, scientists, engineers, and science fiction authors/filmmakers have proposed the idea of combining technology and biology to terraform Mars – in hopes of expanding the human presence in the Solar System. Mars, consequently, is the only other terrestrial planet in the Solar System that has the probability of supporting life – and terraforming seems like a practicable option. Today, planetary scientists argue that the basic elements to revive Mars, such as carbon, nitrogen, and water, exists beneath the Martian soil in sufficient quantities to create an atmosphere and hydrosphere. Recent data by the Mars Global Surveyor satellite, for example, have found indirect traces of water tied up as ice in the polar regions. Moreover, the Mars Reconnaissance Orbiter recently provided convincing evidence that water in the form of liquid flows occasionally on present-day Mars. Terraforming Mars, thus, would focus on introducing a runaway greenhouse effect to thicken and warm the Martian atmosphere, while gradually introducing microbes to bring life to the barren landscape. In principle, terraforming the Red Planet to a Green Planet is essentially restoring the planet back to what it was billions of years ago.

Many in the scientific community, however, remain skeptical of Mars being green again. For example, many scientists believe that radiation, due to Mars’ thin atmosphere and lack of magnetic field, has created an oxidizing agent in the surface, which would destroy any kind of organic molecule or plants. Additionally, the chief hurdle of terraforming Mars is not from a technologically perspective but from a position of commitment. An ambitious project like terraforming Mars would take hundreds or perhaps thousands of years as well as trillions of dollars. No country on Earth, unfortunately, has developed a political or economic system willing to support at great cost an enterprise that will undoubtedly require generations to accomplish. Therefore, the idea of transforming Mars back to a green planet is more science fiction than science – at least for now.

Fraser Cain’s series about terraformation:

How do we terraform Venus

How do we terraform Mars?

Could we terraform Jupiter?

Could we terraform the Moon?

Could we terraform the Sun?

Could we terraform a Black Hole?


People believe in very strange things. Some search for extraordinary explanation where logic and common sense is the right answer. I asked the panel what’s the most bizzare conspiracy theory about space and astronomy they have heard about? Why do people continue to create such stories and resist to listen to scientific explanation?
Andrew Rader (SpaceX engineer, MIT PhD, author)

Many people have a vivid sense of imagination, and are loathe to trust the mainstream story, even if it is supported by evidence. Humans are emotional creatures, and their thinking is often driven by bizarre connections. There is a huge difference between legitimate skepticism (questioning what is true) and supposing the existence of conspiracies on shaky or contrary evidence. There are some real conspiracies, defined as “a secret plan to do something unlawful or harmful”. For example, Lincoln’s assassination surely was a conspiracy by John Wilkes Booth and his band, but I think when most people think of “conspiracy theories”, they mean ones perpetuated by the government (especially in the United States).

Particularly in the United States, there is a mistrust of government. While some skepticism is justified in most things, believing with certainty an alternative and less plausible story is not the same thing. Humans are notoriously bad at accepting uncertainty, so perhaps when evidence appears to be lacking, an alternative story seems attractive. Moreover, this imagined story is conceived to fit the preconceptions of the person imagining it – humans interpret the world through a lens which fits their internal biases, rather than trying to shift their biases to fit the actual world.

The main problem with “conspiracy theories” like alien visitation or a faked Moon landing is that while (almost) anything is possible, the magnitude of the problem is misunderstood. Taking the Moon landing case, millions of people were involved, hardware capable of reaching the Moon was designed, built, and launched multiple times over many years, and the supporting science and engineering supports an actual trip to the Moon. Given that framework, it would have been much harder not to go the the Moon (and keep the whole thing secret) than actually go. The weight of evidence supports the view not that it is absolutely certain we went to the Moon, but that having gone is a much more likely explanation than that the landings were faked.

Antonio Paris (Astronaut Candidate, Astronomy Professor, Planetary Scientist, Space Science Author)

The most bizarre conspiracy theory about space and astronomy is UFO phenomena. Rather than applying science and logic to defend the extraterrestrial hypothesis of UFO phenomena, the UFO community addresses the issue through emotions and confirmation bias. Ufologists have a predisposition to favor information, no matter how fantastic, that confirms their beliefs or assumptions. They display this bias when they gather or remember information selectively or when they interpret it in a biased way. This inclination is especially prominent at UFO conferences when emotionally charged stories of alleged alien abductions and government conspiracies are presented. Those who support the extraterrestrial hypothesis of UFO phenomena, moreover, tend to interpret ambiguous and anecdotal evidence as supporting their existing position. This is often the result of media sound bites, social media, and UFO organizations’ claims that they are “scientific” entities. When confirmation bias is coupled with pareidolia, apophenia, and illusory correlation, the end result is belief perseverance, which contributes to overconfidence and strengthens beliefs even in the face of contrary evidence. Moreover, belief in the extraterrestrial hypothesis of UFO phenomena did not develop into self-validating structures all by themselves. They are the direct result of the UFO community leaders’ often modifying and revising their agenda to conform to the prevailing culture of their memberships. A clear example of this occurred when the UFO community was faced with a serious institutional crisis regarding the U.S. government’s explanation for the 1947 Roswell incident. Rather than accepting the proven fact that the UFO was actually a balloon under the auspices of Project Mogul, the UFO community conveniently resorted to claims of a government coverup.

Pamela Gay (assistant research professor at Southern Illinois University, writer, co-host of Astronomy Cast)

The range of extraordinary emails I get is … extraordinary. Many include notices of “Confidential” and “Top Secret” and go on to explain how they have sorted dark energy or explained away relativity with some novel idea that has no math behind it, and they just need math from someone like me to get that Nobel Prize. I general respond to these with gentle encouragement to please take university physics. Please. Learn. Please?

But these aren’t conspiracy theories. These are just people with their own unique denial of physical reality.

The best conspiracy theory I ever heard was actually shared over far too many glasses of [undisclosed adult beverage] while I had a fabulous conversation with an otherwise utterly sane, rather famous actor I otherwise greatly respect. Because this theory doesn’t appear to be in the public record I’m not going to disclose his name. This fellow presented me with a completely novel (to me) take on the Moon Hoax conspiracy. While he believed we did indeed land on the Moon when we said we did, he felt (and continues to feel) that the broadcast that aired on live TV was actually studio footage put together by Stanley Kuberick using the fabulous NASA lens he had access to. This conspiracy theorist posited that the transmission of the 1969 Superbowl was problematic and NASA couldn’t risk having the Moon transmission get screwed up by technical issues. Thus, we landed and explored, BUT, in his mind, what was seen on TV was pre-filmed in a studio. I have to admit, it makes a certain kind of sense… and that is true of many of the best conspiracy theories… but… it’s not true. (This plays along with William Karel’s movie “The dark side of the moon landing”

There are a lot of bad conspiracy theories out there; ones that make me question how these people function in the workplace. The continued belief by some that there was no Jewish Holocaust in WWII is one of those “How?” conspiracy theories. There are also ones that make me wonder “Could that be true?” The conspiracy around the statistical discrepancies between poll results and election results in the 2000 election leaves me scratching my head. This range of conspiracy theory, however, traces out a unifying idea: they present a reality the believers want to be true.

And at the end of the day, faced with the world we actually have, don’t we all sometimes wish for a different reality?

Nancy Atkinson (Senior Editor for Universe Today, Host of the NASA Lunar Science Institute podcast & a NASA/JPL Solar System Ambassador)

Conspiracy theories are interesting because they allow a unique look into the human psyche and why people believe the things they do. After confronting many astronomy-related conspiracy theories by writing articles and debunking them, I think when people get caught up in hype and drama of these predictions, it mainly comes down to scientific illiteracy and a fear of a concept or thing due to misinformation or misunderstanding.

Moon hoaxers — people who don’t think the Apollo missions went to the Moon — are especially maddening because they refuse to look at the mountain of evidence proving the missions were in fact real. But I think the most perplexing of conspiracy theories is the doomsday/apocalypse/end of the world theme.

I’ve lost count of how many times the world was supposed to end in just my own lifetime, but from ancient Nostradamus to the plethora of 2012 doomsday scenarios to the upcoming supermoon eclipse, predictions of the world ending have been happening for centuries. I’ve never been able to understand why humans seem to have a fixation about this topic, but since we and our planet are still here, that means 100% of the predictions have been wrong! I think we can count on any future predictions of apocalypse being wrong, too, because no one — seriously no one — can predict the future.

It’s disappointing when people use astronomical events like a close passing asteroid, an eclipse, supernova or a comet appearing in the sky to spread fear. Learning about the real science of these objects is much more interesting and fun!

Fraser Cain (publisher at, co-host of Astronomy Cast)

The most bizarre conspiracy has got to be the fact that lots of people don’t believe we ever landed on the Moon. It’s an absolutely classic example of insane conspiracy theory thinking. The “evidence” that the conspiracy theory proponents rely on is essentially, “I don’t think astronauts could survive the radiation of the Van Allen Belts.” Even though there’s plenty of science and actual measurements taken during the Apollo flights through the Belts. I honestly don’t really understand the psychology of conspiracy theories, but we see the same things pop up again and again. We’ve been battling the Nibiru nonsense for almost 20 years now, and it’ll probably still be around 100 years in the future.

Nicole Gugliucci (“Noisy astronomer”, blogger, educator, post-doc)

I was once accused of being part of the “black hole conspiracy.” Yes, this is a thing. Apparently there’s a conspiracy to make people believe in black holes which can’t possibly exist in the “electric universe” in which everything is charged and made of currents or… something. It’s a bizarre belief. That said, I think all of us have the capacity for belief in irrational things, as its how our human brains work and construct explanations of the world. Though I think the curiosity part of science is innate and natural to us, the rigorous methodology is not. So there are many factors that influence resistance to science and belief in pseudo science, but some part of it is, that’s just how our brains seem to work by default.