Google Lunar XPRIZE Update

Earlier this year, I reported on the Google Lunar XPRIZE, the $20 million challenge to land a spacecraft on the Moon, travel at least 500 meters, and transmit HD images and video back to Earth. The original deadline required launch before the end of 2017. Now, Google has stated that the mission needs to be completed by March 31, 2018.

XPRIZE logoWhether this new deadline is an extension or a clarification is open to interpretation. Previous language required teams to launch by December 31, 2017. Some propulsion systems are slow enough that even if the spacecraft was launched in 2017, it could take years to make it to the lunar surface. By requiring mission completion no later than March 31, 2018 a clear end date to the challenge has been set. The good news is that this might buy the teams some more time, with the phrase, “regardless of initiation date” being included. Launches could be conducted into March and still potentially take the prize, so long as they complete the other objectives (land, travel a minimum of 500 meters, and transmit HD images and video back to Earth) before April.

According to the latest info, the five teams competing are still: TeamIndus (India), SpaceIL (Israel), Moon Express (USA), Synergy Moon (International) and HAKUTO (Japan).

The amount of information each team is revealing about their progress varies. TeamIndus appears to be one of the most promotional about their progress with regular updates to their social media pages, YouTube channel and their Medium blog. They even created an anthem for their mission.

The Lunar XPRIZE panel was recently invited to take a tour of the TeamIndus facilities and check their progress. John Zernecki, one of the XPRIZE judges, had the following to say about what the panel saw from TeamIndus:

“They’ve created this very vibrant, dynamic and now very professional organization that really has a chance of doing something really crazy…. Now they are, I would say, within striking distance… They have a very believable, credible mission.

Good luck to TeamIndus and the rest of the teams.

Personally, I’ll be excited if any team wins but I do have a bit of a soft spot for TeamIndus solely because their rover is the most adorable:

Team Indus's ECA rover

Team Indus’s ECA rover – Source: Team Indus

Cassini Week: Goodbye Cassini

On September 15, 2017, Cassini’s extraordinary, decades-long mission ended. The discovery machine sent back its final transmissions before vaporizing within Saturn’s atmosphere. Its atoms now a part of the planet that it put into such sharp focus for us. It marked the end of an era.

The past week has been bittersweet. I’ve spent many hours remembering and sharing some of my favorite Cassini images. I’ve only posted a small fraction of my favorites, and every time I hit the publish button I’d remember another image that I wish I had included. I could devote this entire blog to sharing images and discoveries that we owe to Cassini and never run out of content. The robot was truly remarkable.

I’ve saved my favorite image for today’s post, as I wrap up Cassini Week.

The ringed beauty, Saturn.

The ringed beauty, Saturn – Credit: NASA/JPL/Space Science Institute

This image blew me away the first time I saw it. It’s an image seared into my mind and one I’ll never forget. But there’s more to it than just what you see at first glance. There’s a deeper meaning to be uncovered upon closer inspection.

Look closer at the image above. Click on it; look at it in full screen. On the left side, between Saturn’s brighter main rings and the G ring is a pale blue dot. It’s the same pale blue dot that Carl Sagan waxed poetically about nearly 30 years ago, when we first saw our home planet from a similar perspective.

“That’s here. That’s home. That’s us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives.

The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every “superstar,” every “supreme leader,” every saint and sinner in the history of our species lived there…

There is perhaps no better demonstration of the folly of human conceits than this distant image of our tiny world.”

Sagan’s words have never rang more true.

Cassini, along with all of the other instruments of science, do more than just teach us about the subjects of their attention. They teach us about ourselves. They put our infinitesimally small corner of the Universe in perspective. Cassini showed us worlds we could have hardly imagined. Each discovery making the Universe a little larger, a little more dynamic.

For some, that might make you feel small. Personally, I don’t think that’s a bad thing. It puts our more minor inconveniences and frustrations in perspective. It’s a reminder of how far we’ve come as a species, how fortunate we are to live our lives at such an exciting time.

And, it gives us the tiniest glimpse of the potential of our future.


Cassini Week: Artistic Imagery

We’ve all marveled over Cassini’s images of the Saturn system for more than a decade. Saturn is a truly dynamic place, surrounded by equally dynamic worlds. But Cassini’s images did more than just capture images of these distant places; it created art. Breathtaking ‘landscapes’, magnificent portraits, and photographs perfectly timed and framed. Cassini has all of the skill and talent of a master photographer, with special thanks to its imaging team back on Earth. Below are just a few of my favorite Cassini photos.

Dione, Saturn, Rings, and Enceladus

Dione, Saturn, Rings, and Enceladus – Credit: NASA/JPL-Caltech/SSI

Quintet of Moons

Quintet of Moons – Credit: NASA/JPL-Caltech/Space Science Institute

Janus (179 kilometers, or 111 miles across) is on the far left. Pandora (81 kilometers, or 50 miles across) orbits between the A ring and the thin F ring near the middle of the image. Brightly reflective Enceladus (504 kilometers, or 313 miles across) appears above the center of the image. Saturn’s second largest moon, Rhea (1,528 kilometers, or 949 miles across), is bisected by the right edge of the image. The smaller moon Mimas (396 kilometers, or 246 miles across) can be seen beyond Rhea also on the right side of the image.

Dione, Epimetheus, and Rings

Dione, Epimetheus, and Rings – Credit: NASA/JPL-Caltech/Space Science Institute

Just one more day until Cassini’s Grand Finale. Stay tuned for more Cassini Week celebration.

Cassini Week: Rings

In the famous words of the 21st Century philosopher, Beyoncé, “if you like it then you shoulda put a ring on it”.

In that case, the Universe must have really liked Saturn.

While all of the gas giants in our solar system have rings, Saturn’s are by far the most prominent and celebrated. And while humans have been admiring Saturn’s rings for centuries (when Galileo first discovered them, he described them as Saturn’s ears), it was Cassini that brought them into razor-sharp focus.

Shadows cast on Saturn's A ring.

Shadows cast on Saturn’s A ring. – Credit: NASA/JPL/Space Science Institute

Several sets of shadows are cast onto the A ring in this image taken about a week after Saturn’s August 2009 equinox.

Near the middle of the image, shadows are cast by vertically extended clumps in the kinky, discontinuous ringlets of the Encke Gap in the A ring. These clumps are casting shadows approximately 275 kilometers (170 miles) long, implying a clump height about 600 meters (2,000 feet) above the ring plane.

In the middle left of the image, the waves created by Daphnis (8 kilometers, 5 miles across) on the edge of the Keeler Gap cast shadows on the A ring that are about 450 kilometers (280 miles) long, indicating waves that rise about one kilometer above the ring plane. The moon itself is not visible at this resolution, but it, too, orbits in the Keeler Gap of the A ring. Daphnis has an inclined orbit, and its gravitational pull perturbs the orbits of the particles of the A ring forming the Keeler Gap’s edge and sculpts the edge into waves having both horizontal (radial) and out-of-plane components. Material on the inner edge of the gap orbits faster than the moon so that the waves there lead the moon in its orbit. Material on the outer edge moves slower than the moon, so waves there trail the moon.

The Janus 2:1 spiral density wave

The Janus 2:1 spiral density wave – Credit: NASA/JPL-Caltech/SSI

This view from NASA’s Cassini spacecraft shows a wave structure in Saturn’s rings known as the Janus 2:1 spiral density wave. Resulting from the same process that creates spiral galaxies, spiral density waves in Saturn’s rings are much more tightly wound. In this case, every second wave crest is actually the same spiral arm which has encircled the entire planet multiple times.

Propeller in Saturn's A Ring

Propeller in Saturn’s A Ring – Credit: NASA/JPL-Caltech/Space Science Institute

NASA’s Cassini spacecraft captured these remarkable views of a propeller feature in Saturn’s A ring on Feb. 21, 2017. These are the sharpest images taken of a propeller so far, and show an unprecedented level of detail. The propeller is nicknamed “Santos-Dumont,” after the pioneering Brazilian-French aviator.

Have you heard of Saturn’s propellers before? They’re the result of a very small moon, unseen in the photo above, disturbing ring material. They offer a unique opportunity for researchers to track the orbits of unseen objects that are embedded within a disk of material.

Epimetheus and smog-enshrouded Titan, with Saturn's A and F rings stretching across the scene.

Epimetheus, Titan, and rings. – Credit: NASA/JPL/Space Science Institute

Cassini delivers this stunning vista showing small, battered Epimetheus and smog-enshrouded Titan, with Saturn’s A and F rings stretching across the scene.

Stay tuned for more, as we continue our Cassini Week celebration.

Cassini Week: Huygens Probe 

When Cassini launched in 1997, it carried with it a special payload: a probe named Huygens that would penetrate the permanent haze of Saturn’s largest moon Titan, and reveal to us the shrouded world below.

Huygens descent module and shield

Huygens descent module and shield – Credit: ESA

And what a world Titan is!

It’s larger than Mercury, approaching the diameter of Mars (Titan: 5,150 km / Mars: 6,780 km). It has an atmosphere with superrotating winds, composed of 95 nitrogen and 5% methane. And it has an abundance of massive liquid methane lakes and rivers, as well as water ice and rocks of all sizes. A truly dynamic place that can only be referred to as a world.

And we owe most of what we know about Titan thanks to Huygens and Cassini.

Four images obtained at different altitudes during Titan's descent

Four images obtained at different altitudes during Titan’s descent – Credit: ESA/NASA/JPL/University of Arizona

The probe was named after the man who discovered Titan in 1655, the Dutch astronomer Christiaan Huygens.

Christiaan Huygens

Christiaan Huygens

After a seven year journey, Cassini entered Saturn’s orbit on July 1, 2004. On Christmas Day of that year (Spacecraft Event Time), the shelled Huygens probe separated from Cassini and began its three-week coast to Titan’s surface. Finally, on January 14, 2005, Huygens fell through Titan’s atmosphere, slowed by parachutes, for 2 hours and 27 minutes, before landing on the surface. On the way down, its suite of instruments and cameras captured priceless data about the mysterious world on which it would spend the rest of its life.

First color photo from Titan's surface

First color photo from Titan’s surface – Credit: NASA/JPL/ESA/University of Arizona

Huygens sent data back from the surface of Titan for 72 minutes, before Cassini–our relay station to the probe–dipped below the moon’s horizon. The amount of data collected and transmitted during that short time, however, was phenomenal. In addition to the breathtaking photos, Huygens provided us with unprecedented data about the alien moon, data that is still being analyzed for new discoveries to this day.

Stay tuned for more, as we continue our week of commemorating the Cassini mission on the eve of the spacecraft’s Grand Finale.

Cassini Week: Moons Mimas and Pan

This week we’re celebrating the accomplishments of the Cassini spacecraft which, in just a few days, will plunge into Saturn’s atmosphere in its Grand Finale. Today, we take a look at just two of Saturn’s more than 60 moons: Mimas and Pan.


When it comes to Saturn’s moon Mimas, Cassini kept delivering surprise after surprise. First, there was a fantastic image showing us, in great detail, Mimas’s remarkable Herschel crater (Voyager 1 was the first to give us images of Herschel crater, but they paled in comparison to what Cassini revealed).

Mimas, with prominent Herschel crater.

Mimas, with prominent Herschel crater. – Source: NASA/JPL-Caltech

Then again, maybe…
Obi-Wan Kenobi: "That's no moon. It's a space station."

But Cassini revealed another surprise on Mimas. When it took a look at its infrared profile and created a temperature map, we found Pac-Man.

Mimas Temperature Map

Mimas Temperature Map – Source: NASA/JPL/Goddard/SWRI/SSI


While Mimas is quite a unique satellite of our beloved ringed planet, Pan certainly deserves some recognition as well.

Saturn's ravioli moon, Pan

Saturn’s ravioli moon, Pan – Source: NASA/JPL/Space Science Institute

The above image was captured in March of 2017, as Cassini zoomed within 15,300 miles (24,600 kilometers) of Pan.

I don’t know about you, but this moon makes me hungry for a pan of ravioli.
Will Riker rolling his eyes.

Stay tuned, more Cassini action to come as we prepare for the Grand Finale.

Sunday Matinee – NASA at Saturn: Cassini’s Grand Finale

The final chapter in a remarkable mission of exploration and discovery, Cassini’s Grand Finale is in many ways like a brand new mission. Twenty-two times, NASA’s Cassini spacecraft will dive through the unexplored space between Saturn and its rings. What we learn from these ultra-close passes over the planet could be some of the most exciting revelations ever returned by the long-lived spacecraft. This animated video tells the story of Cassini’s final, daring assignment and looks back at what the mission has accomplished.

Cassini’s Grand Finale

On September 15, one of the most fruitful space missions ever imagined will come to an end. After two decades in space, Cassini’s fuel supplies are close to being depleted. To avoid contaminating one of Saturn’s moons, including a pair that could harbor life–Enceladus and Titan–the decision was made to retire Cassini into Saturn’s atmosphere. Up until contact between the orbiter and Earth is lost, Cassini will continue to study our beloved ringed planet. New insight will be gleaned from this mission that’s only made possible by Cassini’s fatal approach to the gas giant. Among the data to be collected:

  • The spacecraft will make detailed maps of Saturn’s gravity and magnetic fields, revealing how the planet is arranged internally, and possibly helping to solve the irksome mystery of just how fast Saturn is rotating.
  • The final dives will vastly improve our knowledge of how much material is in the rings, bringing us closer to understanding their origins.
  • Cassini’s particle detectors will sample icy ring particles being funneled into the atmosphere by Saturn’s magnetic field.
  • Its cameras will take amazing, ultra-close images of Saturn’s rings and clouds.

Cassini launched on Oct. 15, 1997. After a seven-year journey the orbiter arrived at Saturn, carrying the European Space Agency’s Huygens probe. In 2005, the probe successfully landed on Saturn’s largest moon, Titan.

Quick facts about Titan:

  • Titan is the solar system’s second largest moon.
  • It’s the only moon in our solar system that has cloud systems and a dense, planet-like atmosphere.
  • Titan has liquid hydrocarbon lakes, mountains, and seasonal weather patterns.

For 13 years, Cassini has orbited Saturn and provided us with fascinating information about, not just the planet, but its intricate ring system and many moons.

Cassini mission overview infographic

Cassini mission overview infographic – Click for larger version – Source: NASA/JPL

In addition to the important scientific data that was collected by Cassini, are the breathtaking images that have been collected: storms and aurorae on Saturn, detailed views of the worlds that are Saturn moons, and remarkable visions of Saturn’s sensational rings.

For the next week, we celebrate Cassini’s achievements.

Still from the short film Cassini's Grand Finale, the spacecraft is shown diving between Saturn and the planet's innermost ring.

Still from the short film Cassini’s Grand Finale, the spacecraft is shown diving between Saturn and the planet’s innermost ring. – Credit: NASA/JPL-Caltech

SpaceX Continues To Make History

SpaceX is no stranger to making commercial spaceflight history. They were the first private corporation to launch a liquid-fueled rocket into orbit, send a re-supply spacecraft to the International Space Station, and to land their first-stage rockets back on Earth (for potential re-use), among other milestones. They’re also on the cusp of providing transportation services for International Space Station crew members.

SpaceX Falcon 9 moments before landing on February 19, 2017

SpaceX Falcon 9 moments before landing on February 19, 2017 – Source: SpaceX

On February 19, 2017, SpaceX accomplished another major feat: They became the first private company to launch from the historic Launch Pad 39A at Kennedy Space Center.

Launch Pad 39A

SpaceX became the first commercial corporation to lease space and operate out of Kennedy Space Center when, in 2014, they signed a 20-year lease for the historic Launch Pad 39A. It was from this launch pad that Apollo 11 blasted off for the Moon, when Neil Armstrong and Buzz Aldrin became the first humans to step foot on our lunar neighbor. It also hosted the first Space Shuttle mission, as well as some 90 others. Now, and for at least the next two decades, it’s in the hands of SpaceX, further cementing the foothold that the private sector has made in the space program.

SpaceX and NASA CRS-10 mission patches

SpaceX and NASA CRS-10 mission patches – Source: Public Domain and SpaceX

Launch and Landing

At 9:39am EST, on February 19, SpaceX’s Falcon 9 rocket ignited and thundered into the clouds. The rocket was topped with the Dragon capsule, carrying more than 5,000 pounds (2,267 kg) worth of cargo destined for the International Space Station. Dragon arrived and successfully docked with the ISS a couple of days following launch.

Dr. Michelle Thaller, NASA astrophysicist and contributor to myriad space documentary programs, was at Sunday’s launch and graciously shared her experience with me. “Launches are always wonderfully, viscerally exciting,” she said. “The Falcon 9 has a wonderful, big, booming sound, similar to an Atlas, and it puts on a great fireworks show.”

But that wasn’t the only show in store for the lucky spectators in Florida that day. After shoving Dragon into orbit, the Falcon first stage began its 100-kilometer return trip back to Earth. In fewer than 10 minutes following lift-off, the first stage rocket re-emerged through the clouds and landed at Landing Zone 1, just a few miles away from the launch pad. Thaller described the period of suspense in between the launch and the Falcon landing, and said that in some ways there was more anticipation for the landing than there was for the launch.

[N]othing quite prepares you for what happens 7 minutes later, just as the adrenaline is wearing off. Silently, at first, this 230-foot first stage turns around and comes down out of the sky. Smoothly, surreally, a tower the size of a 15 story building just comes and sets itself down. Only once it’s down do you hear the double pop of a sonic boom. It sort of turns your stomach. Things that big are not supposed to just come out of the sky and land. It’s awesome.

Awesome, indeed. See for yourself:

As a kid, I remember watching cartoons that showed rockets landing on various planets. The rockets would turn themselves around and gently land engine-side down. I would always exclaim, “That’s not how rockets work! They burn up, or have parachutes attached and they land in the ocean! How silly.”

Yet, here we are.

I’ve often been jealous about being born too late to experience the race to the Moon. I’ve been somewhat depressed since watching the last Shuttle mission touch down in 2011. But when I take a step back and look at what is occurring today and what we have to look forward to, I can’t help but recognize what a wonderful time it is to be alive.

You can watch the full webcast of the launch on SpaceX’s YouTube channel.

7 Earth-Sized Worlds Discovered Orbiting Nearby Star

Artist's concept of the surface of TRAPPIST1-f.

Artist’s concept of the surface of TRAPPIST1-f. – Credit: NASA/JPL-Caltech

NASA held a press conference today, announcing an exciting new discovery: A record-breaking seven Earth-sized planets have been discovered orbiting a star located about 40 light years from Earth. Three of these planets are firmly located within what’s called the habitable zone–the area around a star that is likely to have rocky planets with liquid water.

The star is named TRAPPIST-1 (also known as 2MASS J23062928-0502285). It’s an ‘ultra-cool dwarf’ star, with approximately 8% of the mass and 11% of the radius of our Sun. Size-wise, this is approximately the difference between a basketball and a golfball.

The seven plants surrounding TRAPPIST-1 orbit much closer to their star than Earth does to the Sun. As well, these exoplanets are much closer to each other than the planets in our own system. You could stand on one of these planets and see the next closest one with a similar type of view that we have with the Moon here on Earth, and you could clearly make out the disc-shape of many of the other planets rather than mere points of light.

The discoveries were made using data from the Spitzer Space Telescope, which was launched in 2003. Although Spitzer wasn’t specifically designed to observe exoplanets, the suite of instruments it carries allows it to discover exoplanets in the same manner that the Kepler spacecraft uses. These observatories can discover exoplanets by precisely measuring dips in the light emitted from a star that coincides with a planet orbiting in-between that star and our vantage point and blocking a portion of the light that we can measure. Continued observations can determine orbital periods, distance from the star, and the number of exoplanets in a system. This data can be used to plot habitable zones.

During the press conference, the team stated that they had preliminary mass measurements for six of the planets, and they believe that one is likely to have a water-rich composition.

Artist's concept shows what each of the TRAPPIST-1 planets may look like, based on available data about their sizes, masses and orbital distances.

Artist’s concept shows what each of the TRAPPIST-1 planets may look like, based on available data about their sizes, masses and orbital distances. – Credit: NASA/JPL-Caltech

There currently isn’t a system for naming exoplanets in the way that bodies like asteroids are named, so they’re simply provided with alphabetic designations appended to their host stars’ name, with the designation ‘b’ being the closest to the star.

These planets orbit so close to their star that they’re likely tidally-locked in the same manner that the Moon is to the Earth. These planets would have permanent day and night sides.

One of the planets, Trappist-1c, is very similar in size to Earth and receives about the same amount of light as Earth receives from the Sun. It could very well have temperatures similar to those we have on Earth. Trappist-1f has a 9-day orbit and receives about as much light as Mars does. Trappist-1g is the largest planet in the system with an estimated radius 13% larger than Earth.

All of the planets are within a few times the distance between the Earth and the Moon of each other, and being so close to their star their orbits (their years) are about 1.5 Earth days for the closest planet and 20 days for the furthest.

Concept art for TRAPPIST-1 and its seven Earth-sized exoplanets.

Concept art for TRAPPIST-1 and its seven Earth-sized exoplanets. – Credit: NASA/JPL-Caltech

The next step, which is already ongoing, is to study their atmospheres and to look for water. This can be accomplished using a technique called transmission spectroscopy. We have observatories that can do this now, such as the Hubble Space Telescope, and the future James Webb Space Telescope (JWST) will be able to push these capabilities even further. JWST will be able to look for greenhouse gas content and determine the surface temperatures of these planets, as well as detect gases that are produced by life. It’s expected that the first cycle of observations of the JWST will include the TRAPPIST-1 system.

Thomas Zurbuchen, associate administrator of the agency’s Science Mission Directorate in Washington, referred to our moment in time as “the gold rush phase of exoplanet discovery.”  It was just in 1995 that the first exoplanet was discovered, he explained, and that thousands have been discovered since.

Following the announcement, the panel held a Q&A session. During the course of their answers, they explained that there was no indication of these planets having moons, but that if water was present there would be tidal activity resulting from the other planets. They said they expect substantial progress in determining the atmospheric composition of these exoplanets within the next 5 years, utilizing the Hubble Space Telescope and the James Webb Space Telescope after it begins operations in 2018. JWST’s transmission spectroscopy will cover the range needed to determine the potential for life.

One member asked if any attempts have been made to listen to the system with SETI-style instruments, to which there was a reply that SETI itself had listened to the system but hadn’t picked-up any signals.

One of the most interesting answers came from Zurbuchen, when he was asked when we could expect to construct a craft that could journey to this system. Rather than give an estimate in the number of years in the future we could expect such capabilities, he answered with the estimated “number of miracles” that are required before we get there. He explained that the JWST required 10 miracles to become possible. He likened the construction of a craft that could explore TRAPPIST-1 as requiring “100 miracles”, but that we shouldn’t be dissuaded, that to get there you have to “start inventing your way forward.” Some of the “miracles” require advancements in propulsion systems and radiation-protection, and that the good news was that substantial work is already being accomplished towards about 5-10 of these miracles. He said it’s about “leaning forward” and “not backing up”.

Discoveries like these are constant reminders of just how big and amazing our Universe is. We’re reminded that the night sky isn’t just full of points of light, but worlds, perhaps some of which might be very similar to our own.

A poster advertising a hypothetical planet-hopping trip in the Trappist-1 system

A poster advertising a hypothetical planet-hopping trip in the Trappist-1 system – Credit: NASA-JPL/Caltech