SpaceX Makes Progress Replicating Failure that Caused Falcon 9 Pad Explosion

SpaceX Falcon 9 rocket moments after catastrophic explosion destroys the rocket and Amos-6 Israeli satellite payload at launch pad 40 at Cape Canaveral Air Force Station, FL, on Sept. 1, 2016. A static hot fire test was planned ahead of scheduled launch on Sept. 3, 2016. Credit: USLaunchReport
SpaceX Falcon 9 rocket moments after catastrophic explosion destroys the rocket and Amos-6 Israeli satellite payload at launch pad 40 at Cape Canaveral Air Force Station, FL,  on Sept. 1, 2016.  A static hot fire test was planned ahead of scheduled launch on Sept. 3, 2016. Credit: USLaunchReport
SpaceX Falcon 9 rocket moments after catastrophic explosion destroys the rocket and Amos-6 Israeli satellite payload at launch pad 40 at Cape Canaveral Air Force Station, FL, on Sept. 1, 2016. A static hot fire test was planned ahead of scheduled launch on Sept. 3, 2016. Credit: USLaunchReport

SpaceX is making significant progress in replicating the failure in the helium pressurization system that led to the catastrophic launch pad explosion of the firms Falcon 9 rocket during a routine fueling test at their Florida Space Coast launch complex on September 1.

The problem at the heart of the anomaly appears to be in the helium loading system. However the root cause of the explosion still remains elusive at this time.

“The Accident Investigation Team continues to make progress in examining the anomaly on September 1 that led to the loss of a Falcon 9 and its payload at Launch Complex 40 (LC-40), Cape Canaveral Air Force Station, Florida,” SpaceX announced in an Oct. 28 update.

The company had previously said in a statement issued on Sept. 23 that investigators had determined that a “large breach” in the cryogenic helium system of the second stage liquid oxygen tank likely triggered the catastrophic Falcon 9 launch pad explosion that suddenly destroyed the rocket and Israeli Amos-6 commercial payload during the routine fueling test almost two months ago.

“The root cause of the breach has not yet been confirmed, but attention has continued to narrow to one of the three composite overwrapped pressure vessels (COPVs) inside the LOX tank,” SpaceX explained in the new statement issued on Oct. 28.

“Through extensive testing in Texas, SpaceX has shown that it can re-create a COPV failure entirely through helium loading conditions.”

The helium loading is “mainly affected by the temperature and pressure of the helium being loaded.”

And SpaceX CEO and Founder Elon Musk had previously cited the explosion as “most difficult and complex failure” in the firms history.

“Turning out to be the most difficult and complex failure we have ever had in 14 years,” Musk tweeted on Friday, Sept. 9.

Aerial view of pad and strongback damage at SpaceX Launch Complex-40 as seen from the VAB roof on Sept. 8, 2016  after fueling test explosion destroyed the Falcon 9 rocket and AMOS-6 payload at Cape Canaveral Air Force Station, FL on Sept. 1, 2016. Credit: Ken Kremer/kenkremer.com
Aerial view of pad and strongback damage at SpaceX Launch Complex-40 as seen from the VAB roof on Sept. 8, 2016 after fueling test explosion destroyed the Falcon 9 rocket and AMOS-6 payload at Cape Canaveral Air Force Station, FL on Sept. 1, 2016. Credit: Ken Kremer/kenkremer.com

The helium loading procedures may well need to be modified, as an outcome of the accident investigation, to enable safe loading conditions.

SpaceX is conducting a joint investigation of the Sept. 1 anomaly with the FAA, NASA, the US Air Force and industry experts who have been “working methodically through an extensive fault tree to investigate all plausible causes.”

The explosion also caused extensive damage to launch pad 40 as well as to the rockets transporter erector, or strongback, that holds the rocket in place until minutes before liftoff, and ground support equipment (GSE) around the pad – as seen in my photos of the pad taken a week after the explosion during the OSIRIS-REx launch campaign.

Fortunately, many other pad areas and infrastructure survived intact or in good condition.

Overview schematic of SpaceX Falcon 9. Credit: SpaceX
Overview schematic of SpaceX Falcon 9. Credit: SpaceX

The company is conducting an extensive series of ground tests at the firms Texas test site to elucidate as much information as possible as a critical aid to investigators.

“We have conducted tests at our facility in McGregor, Texas, attempting to replicate as closely as possible the conditions that may have led to the mishap.”

The explosion took place without warning at SpaceX’s Space Launch Complex-40 launch facility at approximately 9:07 a.m. EDT on Sept. 1 on Cape Canaveral Air Force Station, Fl, during a routine fueling test and engine firing test as liquid oxygen and RP-1 propellants were being loaded into the 229-foot-tall (70-meter) Falcon 9. Launch of the AMOS-6 comsat was scheduled two days later.

Both the $60 million SpaceX rocket and the $200 million AMOS-6 Israeli commercial communications satellite payload were completely destroyed in a massive fireball that erupted suddenly during the planned pre-launch fueling and hot fire engine ignition test at pad 40 on Sept. 1. There were no injuries since the pad had been cleared.

The rocket disaster was coincidentally captured as it unfolded in stunning detail in a spectacular up close video recorded by my space journalist colleague Mike Wagner at USLaunchReport.

Watch this video:

Video Caption: SpaceX – Static Fire Anomaly – AMOS-6 – 09-01-2016. Credit: USLaunchReport

SpaceX continues to work on root cause and helium loading procedures.

“SpaceX’s efforts are now focused on two areas – finding the exact root cause, and developing improved helium loading conditions that allow SpaceX to reliably load Falcon 9.”

The company also still hopes to resume Falcon 9 launches before the end of 2016.

“Pending the results of the investigation, we continue to work towards returning to flight before the end of the year. Our launch sites at Kennedy Space Center, Florida, and Vandenberg Air Force Base, California, remain on track to be operational in this timeframe.”

At KSC launches will initially take place from pad 39A, the former shuttle pad that SpaceX has leased from NASA.

Pad 40 is out of action until extensive repairs and testing are completed.

SpaceX is renovating Launch Complex 39A at the Kennedy Space Center for launches of the Falcon Heavy and human rated Falcon 9.  Credit: Ken Kremer/kenkremer.com
SpaceX is renovating Launch Complex 39A at the Kennedy Space Center for launches of the Falcon Heavy and human rated Falcon 9. Credit: Ken Kremer/kenkremer.com

The Sept. 1 calamity was the second Falcon 9 failure within 15 months time and will call into question the rockets overall reliability.

The first Falcon 9 failure involved a catastrophic mid air explosion in the second stage about two and a half minutes after liftoff, during the Dragon CRS-9 cargo resupply launch for NASA to the International Space Station on June 28, 2015 – and witnessed by this author.

Although both incidents involved the second stage, SpaceX maintains that they are unrelated – even as they continue seeking to determine the root cause.

SpaceX must determine the root cause before Falcon 9 launches are allowed to resume. Effective fixes must be identified and effective remedies must be verified and implemented.

Stay tuned here for Ken’s continuing Earth and Planetary science and human spaceflight news.

Ken Kremer

Up close view of top of mangled SpaceX Falcon 9 strongback with dangling cables (at right) as seen on Sept. 7 after prelaunch explosion destroyed the rocket and AMOS-6 payload and damaged the pad at Space Launch Complex-40 at Cape Canaveral Air Force Station, FL on Sept. 1, 2016 . Credit: Ken Kremer/kenkremer.com
Up close view of top of mangled SpaceX Falcon 9 strongback with dangling cables (at right) as seen on Sept. 7 after prelaunch explosion destroyed the rocket and AMOS-6 payload and damaged the pad at Space Launch Complex-40 at Cape Canaveral Air Force Station, FL on Sept. 1, 2016 . Credit: Ken Kremer/kenkremer.com
Mangled SpaceX Falcon 9 strongback after prelaunch explosion destroyed the rocket and AMOS-6 payload and damaged the pad. Credit: Ken Kremer/kenkremer.com
Mangled SpaceX Falcon 9 strongback after prelaunch explosion destroyed the rocket and AMOS-6 payload and damaged the pad. Credit: Ken Kremer/kenkremer.com

The Search Is On For Alien Signals Around Tabby’s Star

Credit: UC Berkeley


There’s a remote chance that inexplicable light variations in a star in the Northern Cross may be caused by the works of an alien civilization.

1,480 light years from Earth twinkles one of the greatest mysteries of recent times.  There in the constellation Cygnus the Swan, you’ll find a dim, ordinary-looking point of light with an innocent sounding name — Tabby’s Star.  Named for Louisiana State University astronomer  Tabetha Boyajian, who was the lead author on a paper about its behavior, this star has so confounded astronomers with its unpredictable ups and downs in its brightness, they’ve gone to war on the object, drilling down on it with everything from the Hubble to the monster 393.7-inch (10-meter) Keck Telescope in Hawaii. Continue reading “The Search Is On For Alien Signals Around Tabby’s Star”

What’s the Most Stable Shape for an Interstellar Lightsail?

Project Starshot, an initiative sponsored by the Breakthrough Foundation, is intended to be humanity's first interstellar voyage. Credit: breakthroughinitiatives.org

In 2015, Russian billionaire Yuri Milner founded Breakthrough Initiatives with the intention of bolstering the search for extra-terrestrial life. Since that time, the non-profit organization – which is backed by Stephen Hawking and Mark Zuckerberg – has announced a number of advanced projects. The most ambitious of these is arguably Project Starshot, an interstellar mission that would make the journey to the nearest star in just 20 years.

This concept involves an ultra-light nanocraft that would rely on a laser-driven sail to achieve speeds of up to 20% the speed of light. Naturally, for such a mission to be successful, a number of engineering challenges have to be tackled first. And according to a recent study by a team of international researchers, two of the most important issues are the shape of the sail itself, and the type of laser involved.

The researchers include Elena Popova of the Skobeltsyn Institute of Nuclear Physics in Moscow; Messoud Efendiev of the Institute of Computational Biology (ICB) at the German Research Center for Environmental Health (GmbH); and Ildar Gabitov of the Skoltech Center for Photonics and Quantum Materials in Moscow. Combining their expertise, they conducted a study that examined various stability models for this proposed mission.

As they indicate in their study, titled “On the Stability of a Space Vehicle Riding on an Intense Laser Beam“, the team ran stability simulations 0n the concept, taking into account the nature of the wafer-sized craft (aka. StarChip), the sail (aka. Lightsail) and the nature of the laser itself. For the sake of these simulations, they also factored in a number of assumptions about Starshot’s design.

These included the notion that the StarChip would be a rigid body (i.e. made up of solid material), that the circular sail would either be flat, spherical or conical (i.e. concave in shape), and that the surface of the sail would reflect the laser light. Beyond this, they played with multiple variations on the design, and came up with some rather telling results.

As Dr. Elena Popova, the lead author on the paper, told Universe Today via email:

“We considered different shapes of sail: a) spherical (coincides with parabolic for small sizes) as most appropriate for final configuration of nanocraft en route; b) conical; c) flat (simplest) (will be seen to be unstable so that even spinning of craft does not help).”

What they found was that the simplest, stable configuration would involve a sail that was spherical in shape. It would also require that the StarChip be tethered at a sufficient distance from the sail, one which would be longer than the curvature radius of the sail itself.

A phased laser array, perhaps in the high desert of Chile, propels sails on their journey. Credit: Breakthrough Initiatives.
A phased laser array, perhaps in the high desert of Chile, propels sails on their journey. Credit: Breakthrough Initiatives

“For the sail with almost flat cone shape we obtained similar stability condition,” said Popova. “The nanocraft with flat sail is unstable in every case. It simply corresponds to the case of infinite radius of curvature of the sale. Hence, there is no way to extend center of mass beyond it.”

As for the laser, they considered several how the two main types would effect stability. This included uniform lasers that have a sharp boundary and “Gaussian” beams, which are characterized by high-intensity in the middle that declines rapidly towards the edges. As Dr. Popova stated, they determined that in order to ensure stability – and that the craft wouldn’t be lost to space – a uniform laser was the way to go.

“The nanocraft driven by intense laser beam pressure acting on its Lightsail is sensitive to the torques and lateral forces reacting on the surface of the sail. These forces influence the orientation and lateral displacement of the spacecraft, thus affecting its dynamics. If unstable the nanocraft might even be expelled from the area of laser beam. The most dangerous perturbations in the position of nanocraft inside the beam and its orientation relative to the beam axis are those with direct coupling between rotation and displacement (“spin-orbit coupling”).”

In the end, these were very similar to the conclusions reached by Professor Abraham Loeb and his colleagues at Starshot. In addition to being the Frank B. Baird, Jr. Professor of Science at Harvard University, Prof. Loeb is also the chairman of the Breakthrough Foundation’s Advisory Board. In a study titled Stability of a Light Sail Riding on a Laser Beam” (published on Sept, 29th, 2016), they too examined what was necessary to ensure a stable mission.

This included the benefits of a conical vs. a spherical sail, and a uniform vs. a Gaussian beam. As Prof. Loeb told Universe Today via email:

“We found that a parachute-shaped sail riding on a Gaussian laser beam is unstable… We show in our paper that a sail shaped as a spherical shell (like a large ping-pong ball) can ride in a stable fashion on a laser beam that is shaped like a cylinder (or 3-4 lasers that establish a nearly circular illumination).”

As for the recommendations about the StarChip being at a sufficient distance from the LightSail, Prof. Loeb and his colleagues are of a different mind. “They argue that in case you attach a weight to the sail that is sufficiently well separated from the parachute, you might make it stable.” he said. “Even if this is true, it is unclear that their proposal is useful because such a configuration is rather complicated to build and launch.”

These are just a few of the engineering challenges facing an interstellar mission. Back in September, another study was released that assessed the risk of collisions and how it might effect the Starshot mission. In this case, the researchers suggested that the sail have a layer of shielding to absorb impacts, and that the laser array be used to clear debris in the LightSail’s path.

These conclusions echoed a similar study produced by Professor Phillip Lubin and his colleagues. A professor at the University of California, Santa Barbara (UCSB), Lubin is also one of the chief architects of Project Starshot and the mind behind the NASA-funded Directed Energy Propulsion for Interstellar Exploraiton (DEEP-IN) project and the Directed Energy Interstellar Study.

When Milner and the science team behind Starshot first announced their intention to create an interstellar spacecraft (in April 2016), they were met with a great deal of enthusiasm and skepticism. Understandably, many believed that such a mission was too ambitious, due to the challenges involved. But with every challenge that has been addressed, both by the Starshot team and outside researchers, the mission architecture has evolved.

At this rate, barring any serious complications, we may be seeing an interstellar mission taking place within a decade or so. And, barring any hiccups in the mission, we could be exploring Alpha Centauri or Proxima b up close within our lifetime!

Further Reading: arXiv

Best Photos Yet of the Mars Lander’s Demise

Credit: Schiaparelli lander protected by its heat shield as it enters the Martian atmosphere. Credit: ESA
A closeup of the dark, approximately circular crater about 7.9 feet (2.4 meters) in diameter marking the crash of the Schiaparelli test lander on Mars. The photo was taken on October 25 by NASA's Mars Reconnaissance Lander (MRO). Credit:
A closeup of the dark, approximately circular crater about 7.9 feet (2.4 meters) in diameter that marks the crash of the Schiaparelli test lander on Mars. The new, higher-resolution photo was taken on October 25 by NASA’s Mars Reconnaissance Lander (MRO). A hint of an upraised rim is visible along the crater’s lower left side. The tiny white specks may be pieces of the lander that broke away on impact. The odd dark curving line has yet to be explained.  Credit: NASA/JPL-Caltech

What’s the most powerful telescope for observing Mars? A telephoto lens on the HiRise camera on the Mars Reconnaissance Orbiter that can resolve features as small as 3 feet (1-meter) across. NASA used that camera to provide new details of the scene near the Martian equator where Europe’s Schiaparelli test lander crashed to the surface last week.

The Schiaparelli test lander was protected by its heat shield as it descended through the Martian atmosphere at high speed. Credit: ESA
The Schiaparelli test lander was protected by its heat shield as it descended through the Martian atmosphere at high speed. Credit: ESA

During an October 25 imaging run HiRise photographed three locations where hardware from the lander hit the ground all within about 0.9 mile (1.5 kilometers) of each other. The dark crater in the photo above is what you’d expect if a 660-pound object (lander) slammed into dry soil at more than 180 miles an hour (300 km/h). The crater’s about a foot and a half (half a meter) deep and haloed by dark rays of fresh Martian soil excavated by the impact.

But what about that long dark arc northeast of the crater?  Could it have been created by a piece of hardware jettisoned when Schiaparelli’s propellant tank exploded? The rays are curious too. The European Space Agency says that the lander fell almost vertically when the thrusters cut out, yet the asymmetrical nature of the streaks — much longer to the west than east — would seem to indicate an oblique impact. It’s possible, according to the agency, that the hydrazine propellant tanks in the module exploded preferentially in one direction upon impact, throwing debris from the planet’s surface in the direction of the blast, but more analysis is needed. Additional white pixels in the image could be lander pieces or just noise.

This Oct. 25, 2016, image shows the area where the European Space Agency's Schiaparelli test lander reached the surface of Mars, with magnified insets of three sites where components of the spacecraft hit the ground. It is the first view of the site from the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter taken after the Oct. 19, 2016, landing event and our highest resolution of the scene to date. Annotations by the author. Click for a full-resolution image. Credit: NASA/JPL-Caltech
This Oct. 25, 2016, image shows the area where the European Space Agency’s Schiaparelli test lander reached the surface of Mars, with magnified insets of three sites where components of the spacecraft hit the ground. It is the first view of the site from the High Resolution Imaging Science Experiment (HiRISE) camera on NASA’s Mars Reconnaissance Orbiter taken after the Oct. 19, 2016, landing event and our highest resolution of the scene to date. Click for a full-resolution image. Credit: NASA/JPL-Caltech

In the wider shot, several other pieces of lander-related flotsam are visible. About 0.8 mile (1.4 km) eastward, you can see the tiny crater dug out when the heat shield smacked the ground. Several bright spots might be pieces of its shiny insulation. About 0.6 mile (0.9 kilometer) south of the lander impact site, two features side-by-side are thought to be the spacecraft’s parachute and the back shell.  NASA plans additional images to be taken from different angle to help better interpret what we see.

The last happy scene for the lander when it still dangled from its chute before dropping and slamming into the surface. Credit: ESA
Schiaparelli dangles from its parachute in this artist’s view. A software error caused the chute to deploy too soon. Credit: ESA

The test lander is part of the European Space Agency’s ExoMars 2016 mission, which placed the Trace Gas Orbiter into orbit around Mars on Oct. 19. The orbiter will investigate the atmosphere and surface of Mars in search of organic molecules and provide relay communications capability for landers and rovers on Mars. Science studies won’t begin until the spacecraft trims its orbit to a 248-mile-high circle through aerobraking, which is expected to take about 13 months.

Everything started out well with Schiaparelli, which successfully transmitted data back to Earth during its descent through the atmosphere, the reason we know that the heat shield separated and the parachute deployed as planned. Unfortunately, the chute and its protective back shell ejected ahead of time followed by a premature firing of the thrusters. And instead of burning for the planned 30 seconds, the rockets shut off after only 3. Why? Scientists believe a software error told the lander it was much closer to the ground than it really was, tripping the final landing sequence too early.

Landing on Mars has never been easy. We’ve done flybys, attempted to orbit the planet or land on its surface 44 times. 15 of those have been landing attempts, with 7 successes: Vikings 1 and 2, Mars Pathfinder, the Spirit and Opportunity rovers, the Phoenix Lander and Curiosity rover. We’ll be generous and call it 8 if you count the 1971 landing of Mars 3 by the then-Soviet Union. It reached the surface safely but shut down after just 20 seconds.

Mars can be harsh, but it forces us to get smart.

**** Want to learn more about Mars and how to track it across the sky? My new book, Night Sky with the Naked Eye, which will be published on Nov. 8, covers planets, satellites, the aurora and much more. You can pre-order it right now at these online stores. Just click an icon to go to the site of your choice – Amazon, Barnes & Noble or Indiebound. It’s currently available at the first two outlets for a very nice discount.

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If it Wasn’t Already Strange Enough, now Saturn’s Hexagon Storm is Changing Color

Saturn makes a beautifully striped ornament in this natural-color image, showing its north polar hexagon and central vortex (Credit: NASA/JPL-Caltech/Space Science Institute)

Ever since the Voyager 2 made its historic flyby of Saturn, astronomers have been aware of the persistent hexagonal storm around the gas giant’s north pole. This a six-sided jetstream has been a constant source of fascination, due to its sheer size and immense power. Measuring some 13,800 km (8,600 mi) across, this weather system is greater in size than planet Earth.

And thanks to the latest data to be provided by the Cassini space probe, which entered orbit around Saturn in 2009, it seems that this storm is even stranger than previously thought. Based on images snapped between 2012 and 2016, the storm appears to have undergone a change in color, from a bluish haze to a golden-brown hue.

The reasons for this change remain something of a mystery, but scientists theorize that it may be the result of seasonal changes due to the approaching summer solstice (which will take place in May of 2017). Specifically, they believe that the change is being driven by an increase in the production of photochemical hazes in the atmosphere, which is due to increased exposure to sunlight.

 Natural color images taken by NASA's Cassini wide-angle camera, showing the changing appearance of Saturn's north polar region between 2012 and 2016.. Credit: NASA/JPL-Caltech/Space Science Institute/Hampton University
Natural color images taken by NASA’s Cassini wide-angle camera, showing the changing appearance of Saturn’s north polar region between 2012 and 2016.. Credit: NASA/JPL-Caltech/Space Science Institute/Hampton University

This reasoning is based in part on past observations of seasonal change on Saturn. Like Earth, Saturn experiences seasons because its axis is tilted relative to its orbital plane (26.73°). But since its orbital period is almost 30 years, these seasons last for seven years.

Between November 1995 and August 2009, the hexagonal storm also underwent some serious changes, which coincided with Saturn going from its Autumnal to its Spring Equinox. During this period, the north polar atmosphere became clear of aerosols produced by photochemical reactions, which was also attributed to the fact that the northern polar region was receiving less in the way of sunlight.

However, since that time, the polar atmosphere has been exposed to continuous sunlight, and this has coincided with aerosols being produced inside the hexagon, making the polar atmosphere appear hazy. As Linda J. Spilker, the Cassini mission’s project scientist, told Universe Today via email:

“We have seen dramatic changes in the color inside Saturn’s north polar hexagon in the last 4 years.  That color change is probably the result of changing seasons at Saturn, as Saturn moves toward northern summer solstice in May 2017. As more sunlight shines on the hexagon, more haze particles are produced and this haze gives the hexagon a more golden color.”
This diagram shows the main events of Saturn's year, and where in the Saturnian year the Voyager 1 and Cassini missions occurred. Credit: Ralph Lorenz
Diagram showing he main events of Saturn’s year, and where in the Saturnian year the Voyager 1 and Cassini missions occurred. Credit: Ralph Lorenz

All of this has helped scientists to test theoretical models of Saturn’s atmosphere. In the past, it has been speculated that this six-sided storm acts as a barrier that prevents outside haze particles from entering. The previous differences in color – the planet’s atmosphere being golden while the polar storm was darker and bluish – certainly seemed to bear this out.

The fact that it is now changing color and starting to look more like the rest of the atmosphere could mean that the chemical composition of the polar region is now changing and becoming more like the rest of the planet. Other effects, which include changes in atmospheric circulation (which are in turn the result of seasonally shifting solar heating patterns) might also be influencing the winds in the polar regions.

Needless to say, the giant planets of the Solar System have always been a source of fascination for scientists and astronomers. And if these latest images are any indication, it is that we still have much to learn about the dynamics of their atmospheres.

“It is very exciting to see this transformation in Saturn’s hexagon color with changing seasons,” said Spilker. “With Saturn seasons over 7 years long, these new results show us that it is certainly worth the wait.”

 R. G. French (Wellesley College) et al., NASA, ESA, and The Hubble Heritage Team (STScI/AURA)
The seasons on Saturn, visualized with images taken by the Hubble Heritage Team. Credit: R. G. French (Wellesley College) et al./NASA/ESA/Hubble Heritage Team (STScI/AURA)

It also shows that Cassini, which has been in operation since 1997, is still able to provide new insights into Saturn and its system of moons. In recent weeks, this included information about seasonal variations on Titan, Saturn’s largest moon. By April 22nd, 2017, the probe will commence its final 22 orbits of Saturn. Barring any mission extensions, it is scheduled enter into Saturn’s atmosphere (thus ending its mission) on Sept. 15th, 2017.

Further Reading: NASA/JPL/Caltech

It Took 15 Months, but all of New Horizons’ Data Has Finally Been Downloaded

New Horizon's July 2015 flyby of Pluto captured this iconic image of the heart-shaped region called Tombaugh Regio. Credit: NASA/JHUAPL/SwRI.

Finally, the New Horizons team has their entire “pot of gold.” 15 months after the mission’s flyby of the Pluto system, the final bits of science data from the historic July 2015 event has been safely transmitted to Earth.

“The New Horizons mission has required patience for many years, but we knew the results would be well worth the wait,” New Horizons project scientists Hal Weaver told me earlier this year.

Because of New Horizons’ great distance from Earth and the spacecraft’s low power output (the spacecraft runs on just 2-10 watts of electricity), it has a relatively low ‘downlink’ rate at which data can be transmitted to Earth, just 1-4 kilobits per second. That’s why it has taken so long to get all the science data back to Earth.

Pluto Explored! In 2006, NASA placed a 29-cent 1991 ‘Pluto: Not Yet Explored’ stamp in the New Horizons spacecraft. With the new stamp, the Postal Service recognizes the first reconnaissance of Pluto in 2015 by NASA’s New Horizon mission. The two separate stamps show an artists’ rendering of the New Horizons spacecraft and the spacecraft’s enhanced color image of Pluto taken near closest approach. Credits: USPS/Antonio Alcalá © 2016 USPS
Pluto Explored! In 2006, NASA placed a 29-cent 1991 ‘Pluto: Not Yet Explored’ stamp in the New Horizons spacecraft. With the new stamp, the Postal Service recognizes the first reconnaissance of Pluto in 2015 by NASA’s New Horizon mission. The two separate stamps show an artists’ rendering of the New Horizons spacecraft and the spacecraft’s enhanced color image of Pluto taken near closest approach.
Credits: USPS/Antonio Alcalá © 2016 USPS

“This is what we came for – these images, spectra and other data types that are going to help us understand the origin and the evolution of the Pluto system for the first time,” New Horizons principal investigator Alan Stern said a few months ago during an interview. “We’re seeing that Pluto is a scientific wonderland. The images have been just magical. It’s breathtaking.”

Because it was a flyby, and the spacecraft had just one chance at gathering data from Pluto, New Horizons was designed to gather as much data as it could, as quickly as it could – taking about 100 times more data on close approach to Pluto and its moons than it could have sent home before flying onward. The spacecraft was programmed to send select, high-priority datasets home in the days just before and after close approach, and began returning the vast amount of remaining stored data in September 2015.

New Horizons is now over 3.1 billion miles (5 billion km) away from Earth as it continues its journey through the Kuiper Belt. That translates to a current radio signal delay time of five hours, eight minutes at light speed.
The science team created special software to keep track of all the data sets and schedule when they would be returned to Earth.

New Horizons was about 3.7 million miles (6 million kilometers) from Pluto and Charon when it snapped this portrait late on July 8, 2015. Credits: NASA-JHUAPL-SWRI
New Horizons was about 3.7 million miles (6 million kilometers) from Pluto and Charon when it snapped this portrait late on July 8, 2015.
Credits: NASA-JHUAPL-SWRI

The final item that was received was a portion of a Pluto-Charon observation sequence taken by the Ralph/LEISA imager. It arrived at New Horizons’ mission operations at the Johns Hopkins Applied Physics Laboratory (APL) in Laurel, Maryland, at 5:48 a.m. EDT on Oct. 25. The downlink came via NASA’s Deep Space Network station in Canberra, Australia. It was the last of the 50-plus total gigabits of Pluto system data transmitted to Earth by New Horizons over the past 15 months.

“We have our pot of gold,” said Mission Operations Manager Alice Bowman, of APL.

Bowman also said the team will conduct a final data-verification review of New Horizons two onboard recorders before sending commands to erase all the data on the spacecraft. New Horizons has more work to do, so erasing the “old” data will clear space for new data to be taken during its Kuiper Belt Extended Mission (KEM). The spacecraft will do a series of distant Kuiper Belt object observations as well as perform a close encounter flyby with with a small Kuiper Belt object, 2014 MU69, on Jan. 1, 2019.

“There’s a great deal of work ahead for us to understand the 400-plus scientific observations that have all been sent to Earth,” said Stern. “And that’s exactly what we’re going to do—after all, who knows when the next data from a spacecraft visiting Pluto will be sent?”

You can see all of New Horizons images at the New Horizons/APL website.

Planets Around Stars like Proxima Centauri are Probably Earth-Sized Water Worlds

Artist's impression of an "eyeball" planet, a water world where the sun-facing side is able to maintain a liquid-water ocean. Credit and Copyright: eburacum45/ DeviantArt

Proxima b is the subject of a lot interest these days. And why not? As the closest extrasolar planet to our Solar System, it is the best shot we have at studying exoplanets up close in the near future. However, a recent study from the University of Marseilles indicated that, contrary to what many hoped, the planet may be a “water world” – i.e. a planet where up to half of its mass consists of water.

And now, researchers from the University of Bern have taken this analysis a step further. Based on their study, which has been accepted for publication in the journal Astronomy and Astrophysics (A&A), they have determined that the majority planets that form within the habitable zones of a red dwarf star may be water worlds. These findings could have drastic implications for the search for habitable exoplanets around red dwarf stars.

The research was conducted by Dr. Yann Alibert from the National Centers for Competence in Research (NCCR) PlanetS center and Prof. Willy Benz from the Center of Space and Habitability (CSH). Both of these institutions, which are located at the University of Bern, are dedicated to understanding planetary formation and evolution, as well as fostering a dialogue with the public about exoplanet research.

An artist’s depiction of planets transiting a red dwarf star in the TRAPPIST-1 System. Credit: NASA/ESA/STScl
An artist’s depiction of planets transiting a red dwarf star in the TRAPPIST-1 System. Credit: NASA/ESA/STScl

For the sake of their study, titled “Formation and Composition of Planets Around Very Low Mass Stars“, Alibert and Benz carried out the first computer simulation designed to examine the formation of planets around stars that are ten times less massive than our Sun. This involved creating a model that included hundreds of thousands of identical low-mass stars, which were then given orbiting protoplanetary disks of dust and gas.

They then simulated what would happen if planets began to form from the accretion of these disks. For each, they assumed the existence of ten “planetary embryos” (equal to the mass of the Moon) which would grow and migrate over time, giving rise to a system of planets.

Ultimately, what they found was that the planets orbiting within the habitable zone of their parent star would likely to be comparable in size to Earth – ranging from 0.5 to 1.5 times the radius of Earth, with 1 Earth radii being the average. As Dr. Yann Alibert explained to Universe Today via email:

“In the simulations we have considered here, it appears that the majority of the mass (more than 99%) is in the solids. [W]e therefore start with a protoplanetary disk that is made of solids and gas and 10 planetary embryos. The solids in the disk are planetesimals (similar to present day asteriods, around 1 km in size), that can be dry (if they are located in the hot regions of the protoplanetary disk) or wet (around 50% per mass of water ice, if they are in the cold regions of the disk). The planetary embryos are small bodies, whose mass is similar to the moon mass. We then compute how much of the disk solids are capture by the planetary embryos.”

Artist's impression of the view from the most distant exoplanet discovered around the red dwarf star TRAPPIST-1. Credit: ESO/M. Kornmesser.
Artist’s impression of the view from the most distant exoplanet discovered around the red dwarf star TRAPPIST-1. Credit: ESO/M. Kornmesser.

In addition, the simulations produced some interesting estimates on how much of the planets would consist of water. In 90% of cases, water would account for more than 10% of the planets’ mass. Compare that to Earth, where water covers over 70% of our surface, but makes up only about 0.02% of our planet’s total mass. This would mean that the exoplanets would have very deep oceans and a layer of ice at the bottom, owing to the extreme pressure.

Last, but not least, Alibert and Benze found that if the protoplanetary disks that these planets formed from lived longer than the models suggested, the situation would be even more extreme. All of this could be dire news for those hoping that we might find ET living next door, or that red dwarf stars are the best place to look for intelligent life.

“The fact that many planets are water rich could have potentially very strong (and negative) consequence on the habitability of such planets,” said Dr. Alibert. “In fact, we already showed in other articles (Alibert et al 2013, Kitzmann et al. 2015) that if there is too much water on a planet, this may lead to an unstable climate, and an atmosphere that could be very rich in CO2.”

However, Alibert indicates that these two studies were conducted based on planets that orbit stars similar to our Sun. Red dwarfs are different because they evolve much slower (i.e. the luminosity changes very slowly over time) and they are far more red than our Sun, meaning that the light coming from them has different wavelengths that will interact different with planetary atmospheres.

Artist’s impression of the planet Proxima b orbiting the red dwarf star Proxima Centauri, the closest star to the Solar System. Credit: ESO/M. Kornmesser
Artist’s impression of the planet Proxima b orbiting the red dwarf star Proxima Centauri, the closest star to the Solar System. Credit: ESO/M. Kornmesser

“So, to summarize, it could be that the presence of large amounts of water is not so bad as in the case of solar type stars, but it could also well be that it is even worse for reasons that we do not know,” said Alibert. “Whatever the effect, it is something that is important to study, and we have started working on this subject.”

But regardless of whether or not planets that orbit red dwarf stars are habitable, simulations like this one are still exciting. Aside from offering data on what neighboring planets might look like, they also help us to understand the wide range of possibilities that await us out there. And last, they give us more incentive to actually get out there and explore these worlds up close.

Only be sending missions to other stars can we confirm or deny if they are capable of supporting life. And if in the end, we should find that the most common star in the Universe is unlikely to produce life-giving planets, it only serves to remind us how rare and precious “Earth-like” planets truly are.

Further Reading: University of Bern, arXiv

What is the Mars Curse?

What is the Mars Curse?
What is the Mars Curse?


Last week, ESA’s Schiaparelli lander smashed onto the surface of Mars. Apparently its descent thrusters shut off early, and instead of gently landing on the surface, it hit hard, going 300 km/h, creating a 15-meter crater on the surface of Mars.

Fortunately, the orbiter part of ExoMars mission made it safely to Mars, and will now start gathering data about the presence of methane in the Martian atmosphere. If everything goes well, this might give us compelling evidence there’s active life on Mars, right now.

It’s a shame that the lander portion of the mission crashed on the surface of Mars, but it’s certainly not surprising. In fact, so many spacecraft have gone to the galactic graveyard trying to reach Mars that normally rational scientists turn downright superstitious about the place. They call it the Mars Curse, or the Great Galactic Ghoul.

Mars eats spacecraft for breakfast. It’s not picky. It’ll eat orbiters, landers, even gentle and harmless flybys. Sometimes it kills them before they’ve even left Earth orbit.

NASA’s Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft celebrated one Earth year in orbit around Mars on Sept. 21, 2015. MAVEN was launched to Mars on Nov. 18, 2013 from Cape Canaveral Air Force Station in Florida and successfully entered Mars’ orbit on Sept. 21, 2014. Credit: NASA
NASA’s Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft celebrated one Earth year in orbit around Mars on Sept. 21, 2015. MAVEN was launched to Mars on Nov. 18, 2013 from Cape Canaveral Air Force Station in Florida and successfully entered Mars’ orbit on Sept. 21, 2014. Credit: NASA

At the time I’m writing this article in late October, 2016, Earthlings have sent a total of 55 robotic missions to Mars. Did you realize we’ve tried to hurl that much computing metal towards the Red Planet? 11 flybys, 23 orbiters, 15 landers and 6 rovers.

How’s our average? Terrible. Of all these spacecraft, only 53% have arrived safe and sound at Mars, to carry out their scientific mission. Half of all missions have failed.

Let me give you a bunch of examples.

In the early 1960s, the Soviets tried to capture the space exploration high ground to send missions to Mars. They started with the Mars 1M probes. They tried launching two of them in 1960, but neither even made it to space. Another in 1962 was destroyed too.

They got close with Mars 1 in 1962, but it failed before it reached the planet, and Mars 2MV didn’t even leave the Earth’s orbit.

Five failures, one after the other, that must have been heartbreaking. Then the Americans took a crack at it with Mariner 3, but it didn’t get into the right trajectory to reach Mars.

Mariner IV encounter with Mars. Image credit: NASA/JPL
Mariner IV encounter with Mars. Image credit: NASA/JPL

Finally, in 1964 the first attempt to reach Mars was successful with Mariner 4. We got a handful of blurry images from a brief flyby.

For the next decade, both the Soviets and Americans threw all kinds of hapless robots on a collision course with Mars, both orbiters and landers. There were a few successes, like Mariner 6 and 7, and Mariner 9 which went into orbit for the first time in 1971. But mostly, it was failure. The Soviets suffered 10 missions that either partially or fully failed. There were a couple of orbiters that made it safely to the Red Planet, but their lander payloads were destroyed. That sounds familiar.

Now, don’t feel too bad about the Soviets. While they were struggling to get to Mars, they were having wild success with their Venera program, orbiting and eventually landing on the surface of Venus. They even sent a few pictures back.

Finally, the Americans saw their greatest success in Mars exploration: the Viking Missions. Viking 1 and Viking 2 both consisted of an orbiter/lander combination, and both spacecraft were a complete success.

View of Mars from Viking 2 lander, September 1976. (NASA/JPL-Caltech)
View of Mars from Viking 2 lander, September 1976. (NASA/JPL-Caltech)

Was the Mars Curse over? Not even a little bit. During the 1990s, the Russians lost a mission, the Japanese lost a mission, and the Americans lost 3, including the Mars Observer, Mars Climate Orbiter and the Mars Polar Lander.

There were some great successes, though, like the Mars Global Surveyor and the Mars Pathfinder. You know, the one with the Sojourner Rover that’s going to save Mark Watney?

The 2000s have been good. Every single American mission has been successful, including Spirit and Opportunity, Curiosity, the Mars Reconnaissance Orbiter, and others.

But the Mars Curse just won’t leave the Europeans alone. It consumed the Russian Fobos-Grunt mission, the Beagle 2 Lander, and now, poor Schiaparelli. Of the 20 missions to Mars sent by European countries, only 4 have had partial successes, with their orbiters surviving, while their landers or rovers were smashed.

Is there something to this curse? Is there a Galactic Ghoul at Mars waiting to consume any spacecraft that dare to venture in its direction?

ExoMars 2016 lifted off on a Proton-M rocket from Baikonur, Kazakhstan at 09:31 GMT on 14 March 2016. Copyright ESA–Stephane Corvaja, 2016
ExoMars 2016 lifted off on a Proton-M rocket from Baikonur, Kazakhstan at 09:31 GMT on 14 March 2016. Copyright ESA–Stephane Corvaja, 2016

Flying to Mars is tricky business, and it starts with just getting off Earth. The escape velocity you need to get into low-Earth orbit is about 7.8 km/s. But if you want to go straight to Mars, you need to be going 11.3 km/s. Which means you might want a bigger rocket, more fuel, going faster, with more stages. It’s a more complicated and dangerous affair.

Your spacecraft needs to spend many months in interplanetary space, exposed to the solar winds and cosmic radiation.

Arriving at Mars is harder too. The atmosphere is very thin for aerobraking. If you’re looking to go into orbit, you need to get the trajectory exactly right or crash onto the planet or skip off and out into deep space.

And if you’re actually trying to land on Mars, it’s incredibly difficult. The atmosphere isn’t thin enough to use heatshields and parachutes like you can on Earth. And it’s too thick to let you just land with retro-rockets like they did on the Moon.

Schiaparelli lander descent sequence. Image: ESA/ATG medialab
Schiaparelli lander’s planned descent sequence. Image: ESA/ATG medialab

Landers need a combination of retro-rockets, parachutes, aerobraking and even airbags to make the landing. If any one of these systems fails, the spacecraft is destroyed, just like Schiaparelli.

If I was in charge of planning a human mission to Mars, I would never forget that half of all spacecraft ever sent to the Red Planet failed. The Galactic Ghoul has never tasted human flesh before. Let’s put off that first meal for as long as we can.

How Will We Get to Mars? New Book and TV Series Provide the Details

What is it going to take to really get humans to Mars? A new television series and a companion book take a detailed and hard look at the future of Mars exploration. The six-part documentary series on the National Geographic Channel and the book by veteran, award-winning space journalist Leonard David are both titled, “Mars: Our Future on the Red Planet.”

The TV series debuts on November 14, 2016 and was produced by Academy Award-winning filmmaker Ron Howard (Apollo 13) and NASA scientist Brian Grazer. It combines interviews with some of the prominent ‘movers and shakers’ in the space community along with a scripted drama that portrays a human mission to Mars in the year 2033. Together, the show “tells the story of how we will one day call the Red Planet home through groundbreaking research and innovation.”

Watch the trailer:

Leonard David’s thoroughly researched book contains a wealth of information on the technological and sociological hurdles that need to be surmounted to make humans on Mars a reality, as well as revealing what work is currently being done on the road to the Red Planet. The books is large format, filled with stunning, full-color images throughout that provide a feast for the eye, including actual images from our spacecraft as well as illustrations of what future missions might entail.

While the book includes some portrayals of the television series’ drama of the crew of the Daedalus mission as they land on Mars and set up the first human base, the real drama comes from David’s interviews with real-life experts, the men and women who are fervently working towards the day an actual human mission goes to Mars.

I had the chance to talk with David about his new book, and asked what it was like to write a book in conjunction with a television series.

Author Leonard David speaking at the Mars Society meeting in Washington, DC. Image courtesy Leonard David.
Author Leonard David speaking at the Mars Society meeting in Washington, DC. Image courtesy Leonard David.

“It was a really interesting experience,” he said, “and we had a close-knit team that had telecons every week to try and synchronize the themes we were using. There were a few topics I wanted to make sure I was able to include, and there were several themes that the whole team wanted to make sure was included in both the book and the show.”

For example, the imagery in the book and the premise of the show reflect that a mission to Mars is likely going to be a global endeavor. “I wanted to make sure to emphasize this will not be just a US or NASA enterprise, and also that a lot of other countries are exploring Mars with spacecraft right now,” David said.

And so, the images in the book come from multi-national sources, and several are pictures I had never seen before, including the latest images from spacecraft, unique illustrations, and distinctive maps of potential human landing sites on Mars that are almost impossible to stop looking at.

Destination Mars: a detailed map of Mars from National Geographic. Credit: National Geographic.
Destination Mars: a detailed map of Mars from National Geographic. Credit: National Geographic.

David said that with the book, he didn’t want to take a stand on all the issues but combine as much information as possible to make it all available for people to think about.

He also said he wanted to portray the true realities of a human expedition to Mars.

“I wanted to make sure people understand that it’s not just throwing a bunch of tin cans on the surface of Mars and then jamming people in them,” he said. “There are so many other issues: sociological issues, there are cultural issues, and there are ethics issues particularly on the topic of possibly terraforming Mars. I just wanted to write a book that I haven’t already read, and I hit on themes that I don’t recall other books getting to.”

For example, David interviews Frank White, author of the seminal book “The Overview Effect,” and that title is now used as an evocative term to explain how seeing Earth from space has changed the human perspective and experience. But David asks White to consider what The Overview Effect will mean for human Martians.

“The Martians will soon develop their own culture and seem like true ‘aliens’ to Earthlings,” envisions White, leading ultimately to a “declaration of independence” from Earth by Mars.

Similarly, David’s discussions with Nick Kanas, professor emeritus in the department of psychiatry at the University of California, San Francisco, covers what Kanas calls “Earth out of view,” which means that since Earth is so far away, any future human Martians will have to solve their own problems. Therefore, any physical or mental issues that arise will have to be dealt with locally.

It could highlight a sense of isolation, being distant and away from everything, [Kanas adds]. “It’s a different sort of state. Whether that will produce depression, or psychosis, or extreme homesickness… I don’t know. We have a lot of questions that Mars is going to raise, and we don’t have the answers.”

And there are other realities that need to be considered.

“There will be death,” David said. “Mars is out to kill you to begin with, and there will be accidents and people will likely lose their life in some way. It’s going to call upon the pioneering spirit, and it will challenge us not only technologically, but psychologically and physiologically.”

David looks at the technology that will be required: the potential propulsion systems, how to ramp up current entry, descent and landing (EDL) systems for larger human-sized payloads, and the imperative of using what’s called In Situ Resource Utilization (ISRU).

Future missions to Mars and other locations in the Solar System may depend heavily on the skills of planetary geologists. Credit: NASA Ames Research Center
Future missions to Mars and other locations in the Solar System may depend heavily on the skills of planetary geologists. Credit: NASA Ames Research Center

“If we are going to try to avoid having these missions be just flags and footprints like the Apollo missions, it’s going to require living off the land on Mars,” David said.

Again, the experts David interviewed – called “The Heroes” in the book — provide an incredible depth of insight on all the issues facing a human mission to Mars. The Heroes include people such as historian John Logsdon, policy experts like Marcia Smith, entrepreneurs and innovators like Elon Musk, Mars engineers like JPL’s Rob Manning, planetary scientists such as NASA’s Chris McKay and Planetary Protection Officer Catherine Conley, then astronauts like Stanley Love who have already been on the front lines of long duration spaceflight and veteran Buzz Aldrin whose lifetime of experiences provide a unique perspective on human exploration. Reading the words of these experts was perhaps my favorite part of the book (besides those intriguing maps!)

With NASA and other space agencies now embracing Mars as the ultimate human destination, David said the time is now ripe for looking at all the issues that lie ahead on the path to Mars.

“This is a unique time,” he said. “I believe we are in a period that I call ‘now history.’ Never before in our history have we had the potential for the technology, communications and all the other things we need to go off the planet; we’ve never been here before. I think we have an opportunity to create this ‘now history,’ and what we do here and now is going to be a flagship for the future as far as our ability to not only go to Mars, but to go beyond to other planets as well.”

David said he hadn’t yet seen all the footage from the television series, but he was impressed with what he has watched so far. “Ron Howard is pretty good at this stuff, and so the quality is definitely there.” David also indicated there is a bit of a surprise ending to the show, so make sure to stay tuned.

Leonard David is a long-time contributor to Space.com and he writes a column for that site called Space Insider. He is also the coauthor of Buzz Aldrin’s book, “Mission to Mars.” You can find more articles by David at his website, Inside Outer Space.

More information on the book and how to purchase it can be found at the Nat Geo website, or at Amazon, and additional information on the television series can be found here.

ng-mars-book-cover

What is a Waxing Moon?

The waxing gibbous Moon closes in on Aldebaran (lower left). Image credit and copyright: Sarah & Simon Fisher

As you’ve probably noticed, the Moon looks different from one evening to the next. Sometimes we see a New Moon, when the Moon is enshrouded in shadow. At other times, we see a Full Moon, when the entire face of the Moon is illuminated. And of course, there are the many phases in between, where portions of the Moon are illuminated.

This is what is called a Lunar Cycle, a 29 ½-day period (aka. lunar month) where the Moon becomes brighter and dimmer, depending on its orientation with the Earth and the Sun. During the first half of a lunar month, when the amount of illumination on the Moon is increasing, astronomers call this a “waxing moon”.

Lunar Cycle:

To understand the Lunar Cycle, we first must consider the Moon’s orbit in relation to Earth. Basically, the Moon orbits Earth, and Earth orbits the Sun, which means the Moon is always half illuminated by the latter. But from our perspective here on Earth, which part of the Moon is illuminated – and how much – changes over time.

When the Sun, the Moon and Earth are perfectly lined up, the angle between the Sun and the Moon is 0-degrees. At this point, the side of the Moon facing the Sun is fully illuminated, and the side facing the Earth is enshrouded in darkness. We call this a New Moon.

After this, the phase of the Moon changes, because the angle between the Moon and the Sun is increasing from our perspective. A week after a New Moon, and the Moon and Sun are separated by 90-degrees, which effects what we will see. And then, when the Moon and Sun are on opposite sides of the Earth, they’re at 180-degrees – which corresponds to a Full Moon.

Waxing vs. Waning:

The period in which a Moon will go from a New Moon to a Full Moon and back again is known as “Lunar Month”. One of these lasts 28 days, and encompasses what are known as “waxing” and “waning” Moons. During the former period, the Moon brightens and its angle relative to the Sun and Earth increases.

A waxing gibbous Moon from October 12th, headed towards Full this weekend. Image credit and copyright: John Brimacombe.
A waxing gibbous Moon from October 12th, headed towards Full this weekend. Image credit and copyright: John Brimacombe.

When the Moon is in between the Earth and the Sun, the side of the Moon facing away from the Earth is fully illuminated, and the side we can see is shrouded in darkness. As the Moon orbits the Earth, the angle between the Moon and the Sun increases. At this point, the angle between the Moon and Sun is 0 degrees, which gradually increases over the next two weeks. This is what astronomers call a waxing moon.

After the first week, the angle between the Moon and the Sun is 90-degrees and continues to increase to 180-degrees, when the Sun and Moon are on opposite sides of the Earth. When the Moon starts to decrease its angle again, going from 180-degrees back down to 0-degrees, astronomers say that it’s a waning moon. In other words, when the Moon is waning, it will have less and less illumination every night until it’s a New Moon.

Waxing Phases:

The period when the Moon is waxing occurs between a New Moon and a Full Moon, which is characterized by many changes in appearance. The first is known as a Waxing crescent, where 1-49% of the Moon is illuminated. Which side appears illuminated will depend on the observer’s location. For those living in the northern hemisphere, the right side will appear illuminated; whereas for those in the southern hemisphere, the reverse is the case.

Next up is the First Quarter, where 50% of the Moon’s face is illuminated – again, the right side for those in the northern hemisphere and the left for those in the south. This is followed by a Waxing Gibbous Moon, where 51 – 99% of the Moon’s surface is illuminated – right side in the northern hemisphere, left side in the southern. The waxing phase concludes with a Full Moon.

We have written many articles about the Moon here at Universe Today. Here’s What are the Phases of the Moon?, What is a Waning Moon?, What is a Hunter’s Moon?, A Red Moon – Not a Sign of the Apocalypse!, How Did the Moon Form? and What is the Distance to the Moon?

NASA has a cool list of all the Moon phases over the course of 6000 years. And here’s a calculator that shows the current phase of the Moon.

You can listen to a very interesting podcast about the formation of the Moon from Astronomy Cast, Episode 17: Where Did the Moon Come From?

Sources: