November 22, 2016November 26, 2016 by Nancy Atkinson

Cassini Is About To Graze Saturn’s Rings In Mission Endgame

A lovely view of Saturn and its rings as seen by the Cassini spacecraft on Aug. 12, 2009. Credit: NASA/JPL-Caltech/Space Science Institute.

There is a Twitter-bot that randomly tweets out “NOOOOOOOO Cassini can’t be ending!” (with varying amounts of “O’s”). @CassiniNooo represents the collective sigh of sadness and consternation felt by those of us who can’t believe the the historic and extensive Cassini mission will be over in just a matter of months.

And next week is the beginning of the end for Cassini.

On November 30, Cassini will begin a phase of the mission that the science team calls “Cassini’s Ring-Grazing Orbits,” as the spacecraft will start skimming past the outer edge of the rings, coming within – at times — 4,850 miles (7,800 kilometers) of the rings.

“The scientific return will be incredible,” Linda Spilker, Cassini project scientist, told me earlier this year. “We’ll be studying things we just couldn’t do any other place.”

Between November 30, 2016 and April 22, 2017 Cassini will circle high over and under the poles of Saturn, diving every seven days for a total of 20 times through the unexplored region at the outer edge of the main rings.

During the close passes, Cassini’s instruments will attempt to directly sample the icy ring particles and molecules of faint gases that are found close to the rings. Cassini will also capture some of the best high-resolution images of the rings, and garner the best views ever of the small moons Atlas, Pan, Daphnis and Pandora, which orbit near the rings’ outer edges.

During the first two ring-grazing orbits, the spacecraft will pass directly through an extremely faint ring produced by tiny meteors striking the two small moons Janus and Epimetheus. Later ring crossings in March and April will send the spacecraft through the dusty outer reaches of the F ring.

“Even though we’re flying closer to the F ring than we ever have, … there’s very little concern over dust hazard at that range,” said Earl Maize, Cassini project manager at JPL.

Of course, the ultimate ‘endgame’ is that Cassini will plunge into Saturn with its “Grand Finale,” ending the mission on September 15, 2017. Since Cassini is running out of fuel, destroying the spacecraft is necessary to ensure “planetary protection,” making sure any potential microbes from Earth that may still be attached to the spacecraft don’t contaminate any of Saturn’s potentially habitable moons.

This graphic illustrates the Cassini spacecraft's trajectory, or flight path, during the final two phases of its mission. The view is toward Saturn as seen from Earth. The 20 ring-grazing orbits are shown in gray; the 22 grand finale orbits are shown in blue. The final partial orbit is colored orange. Image credit: NASA/JPL-Caltech/Space Science Institute — This graphic illustrates the Cassini spacecraft’s trajectory, or flight path, during the final two phases of its mission. The view is toward Saturn as seen from Earth. The 20 ring-grazing orbits are shown in gray; the 22 grand finale orbits are shown in blue. The final partial orbit is colored orange. Image credit: NASA/JPL-Caltech/Space Science Institute

To prepare for the Grand Finale, Cassini engineers have been slowly adjusting the spacecraft’s orbit since January of this year, doing maneuvers and burns of the engine to bring Cassini into the right orbit so that it can ultimately dive repeatedly through the narrow gap between Saturn and its rings, before making its mission-ending plunge. During some of those final orbits, Cassini will pass as close as 1,012 miles (1,628 kilometers) above the cloudtops of Saturn.

One question for Cassini’s engineering team is how much fuel is actually left in the tank for Cassini’s main engines, which do the majority of the work for orbit adjustments. Each time they’ve used the main engines this past year, the team has held their breath, hoping there is enough fuel.

One final burn of the main engine remains, on December 4. This maneuver is important for fine-tuning the orbit and setting the correct course to enable the remainder of the mission, said Maize.

“This will be the 183rd and last currently planned firing of our main engine,” he said. “Although we could still decide to use the engine again, the plan is to complete the remaining maneuvers using thrusters,” said Maize.

A montage of images from Cassini of various moons and the rings around Saturn. Credit: NASA/JPL-Caltech/Space Science Institute

When I visited with Maize and Spilker earlier this year, Spilker wistfully said that they had begun to experience some of the “lasts” of the mission — the final flyby of Enceladus and other moons. And there’s one big “last” coming up: on Nov. 29, 2016, Cassini will come within 6,800 miles (11,000 km) of Titan, the final flyby of this eerily Earthlike but yet totally alien moon.

This final flyby, named Flyby T-125 has two primary goals: Mapmaking of Titan’s surface, and enabling the change in Cassini’s orbit to begin the end of the mission. But it also might be the most daring and thrilling part of Cassini’s nearly 20-year mission.

But still ….. NOOOOOO!

Keep track of Cassini’s latest endeavours at the Cassini website

November 22, 2016November 26, 2016 by Matt Williams

The Fire In Orbit This Time… Again

Orbital ATK's Cygnus cargo spacecraft is captured using the Canadarm2 robotic arm on the International Space Station. Credit: NASA

Back in October, the Cygnus CRS OA-5 mission (aka. the Orbital Sciences CRS Flight 5) rendezvoused with the International Space Station. As part of Orbital ATK craft’s sixth Commercial Resupply mission to the ISS, the unmanned spacecraft spent the past month berthed with the station, delivering 2,268 kg (5,000 pounds) of cargo and experiments and taking on 1,120 kilograms (2,469 pounds) of trash.

As of this Monday, November 21st, the spacecraft – named the “S.S. Alan Poindexter” in honor of the deceased Space Shuttle commander who died in 2012 – separated from the station’s Unity Module, and will spend the next week performing standalone operations. These have included the much-anticipated Spacecraft Fire Experiment 2 (aka. Saffire-II), which is managed by NASA’s Glenn Research Center.

This experiment, which began just five hours after the shuttle detached from the station (and after it conducted an orbit-raising maneuver), involved the Cygnus controllers deliberately starting a fire inside the spacecraft’s pressurized cabin. The purpose of this was to investigate how fuel combustion works and fires grow in a microgravity environment.

*The Spacecraft Fire Experiment (aka. Saffire) is an attempt by NASA scientists to see how fire behaves in microgravity environments. Credit: NASA*

How fire behaves in space is one of the least understood hazards facing crewed exploration. Until now, research has been limited, and for obvious reasons. Starting a controlled fire in a microgravity environment, especially when you don’t even know how it will behave, is an extremely risky venture. All previous tests that were carried out were severely restricted in size, and yielded very little information.

In contrast, the uncrewed portion of the Cygnus mission offers NASA scientists a rare opportunity to conduct a microgravity fire test aboard a spacecraft. Not only are they hoping to address how fires can ignite, but also how large they can grow in microgravity, how they may consume materials the spacecraft is built from, and eventually die.

As Jitendra Joshi, the technology integration lead for NASA’s Advanced Exploration Systems division, said in an interview with Spaceflight Now, such tests are critical for developing fire countermeasures:

“One of the least understood risks in space is how fire propagates (and) starts. How do you control the fire? How do you detect the fire? All these things. You can’t call 911 like on Earth to come help you.”

In addition to being pressurized, the inside of the Cygnus spacecraft also contained samples of material that are commonly found aboard the ISS. NASA was also sure to include materials that would be included in future tests of the Orion capsule, since such tests are of extreme importance to their “Journey to Mars” and other long-range, long-duration missions.

This was the second experiment conducted as part of the Saffire program, which is managed by NASA’s Advanced Exploration Systems Division, part of the Glenn Research Center. It follows on the heels of the highly successful Saffire-I experiment, which took place in July of 2016. In that experiment, samples of a cotton-fiberglass blend were ignited inside an enclosure aboard a Cygnus vehicle, which consisted of a flow duct and avionics bay.

The samples themselves measured 0.4 meter wide by 1 m long, and were ignited by a hot wire inside an enclosure measuring half a meter wide, 1 meter deep and 1.3 meter long. Prior to this experiment, the largest fire experiment that had ever been conducted in space was about the size of an index card.

The Saffire-II experiment (the second of three proposed fire tests) began just after 18:15 Eastern Time (23:15 UTC ) on November 21st, as the first of nine samples was ignited aboard the craft. This time around, the samples included a cotton-fiberglass blend, Nomex (a flame resistant material used commonly aboard spacecraft), and the same acrylic glass that is used for spacecraft windows.

The nine samples burned for a total of two hours before dying out, and yielded much useful information. As Gary Ruff, Saffire’s project manager, said in a previous NASA press release:

“A spacecraft fire is one of the greatest crew safety concerns for NASA and the international space exploration community. Saffire is all about gaining a better understanding of how fire behaves in space so NASA can develop better materials, technologies and procedures to reduce crew risk and increase space flight safety.”

The third and final experiment for the Spacecraft Fire Experiment series (Saffire-III) is scheduled to take place during the OA-7 mission, which is scheduled to take place in March of 2017. With all three experiments complete, NASA hopes to have accumulated enough data to help guide the selection and construction of future spacecraft, subsystems and instruments.

They also hope that these experiments will help mission planners come up with operational protocols designed to address fires during future crewed missions. These will be especially handy during missions where astronauts don’t have the option of exiting to a docked spacecraft and returning to Earth (as they do aboard the ISS).

The Cygnus craft is now moving on to deploy the four LEMUR CubeSats, which will happen on Friday, November 25th. These CubeSats are part of a growing community of satellites that provide global ship tracking and weather monitoring services.

Following this, Cygnus will remain in orbit for two more days before conducting two burns that will cause it to deorbit and burn up in out atmosphere – which will take place on Sunday, November 27th.

Further Reading: NASA Spaceflight, Spaceflight Now, NASA AES – Saffire

November 19, 2016November 26, 2016 by Matt Williams

Stephen Hawking Issues A Wake Up Call

Stephen Hawking recently issued some more dire warnings for humanity, saying that we have 1000 years to find a new planet. Credit: Public Domain/photo by Alexandar Vujadinovic

It has been argued that the greatest reason our species should explore space and colonize other planets is so that a cataclysmic fate won’t be able to claim all of humanity. That is the driving force behind Elon Musk’s plan to colonize Mars. And it has certainly been the driving point behind Stephen Hawking’s belief that humanity should become an interplanetary-species.

And according to Hawking, becoming interplanetary is something of a time-sensitive issue. During a recent speech presented at the Oxford Union Society (Oxford University’s prestigious debating society) Hawking laid it out plainly for the audience. Humanity has 1000 years to locate and colonize new planets, he claimed, or we will likely go extinct.

For almost 200 years, the Oxford Union Society has been a forum for intellectual debate. In the past, it has also hosted such speakers as the Dalai Lama, Stephen Fry, Morgan Freeman, Richard Dawkins, and Buzz Aldrin. On this occasion, Hawking addressed a crowd of students and professors about space exploration and humanity’s future – two subjects he’s well versed in!

*Stephen Hawking is a major proponent for colonizing other worlds, mainly to ensure humanity does not go extinct. Credit: educatinghumanity.com*

As Hawking made clear, humanity faces a number of existential threats, many of which are going to become a serious problem during the 21 century century. These include, but are not limited to, the threat of Climate Change, nuclear holocaust, terrorism, and the rise of artificial intelligence. The solution, Hawking argued, is to get into space and establish colonies as soon as possible.

As he was quoted as saying by the Christian Science Monitor, this will need to take place within the next 1000 years:

“Although the chance of a disaster to planet Earth in a given year may be quite low, it adds up over time, and becomes a near certainty in the next 1,000 or 10,000 years. By that time we should have spread out into space, and to other stars, so a disaster on Earth would not mean the end of the human race.”

This was not the first time Hawking has expressed concerns about the future. In January of 2015, Hawking joined Elon Musk and many other AI experts to pen the “Research Priorities for Robust and Beneficial Artificial Intelligence” – aka. the “Open Letter on Artificial Intelligence”. In this letter, he and the other signatories raised concerns about the short-term and long-term implications of AI, and urged that steps be taken to address them.

President Barack Obama talks with Stephen Hawking in the Blue Room of the White House before a ceremony presenting him and 15 others the Presidential Medal of Freedom, August 12, 2009. The Medal of Freedom is the nation's highest civilian honor. (Official White House photo by Pete Souza) — President Barack Obama talks with Stephen Hawking in the Blue Room of the White House before a ceremony presenting him and 15 others the Presidential Medal of Freedom on August 12th, 2009. Credit: whitehouse.gov/Pete Souza

In addition, back in January of 2016, Hawking warned that humanity’s technological progress has the power to outstrip us. This occurred during his speech at the 2016 Leith Lectures, where Hawking spoke about black holes and why they are fascinating. During the Q&A period that followed, Hawking turned to the much more dour subject of whether or not humanity has a future. As he said at the time:

“We face a number of threats to our survival, from nuclear war, catastrophic global warming, and genetically engineered viruses. The number is likely to increase in the future, with the development of new technologies, and new ways things can go wrong. However, we will not establish self-sustaining colonies in space for at least the next hundred years, so we have to be very careful in this period. Most of the threats we face come from the progress we have made in science and technology. We are not going to stop making progress, or reverse it, so we have to recognize the dangers and control them. I am an optimist, and I believe we can.”

Similarly, Hawking indicated back in 2010 that humanity’s survival beyond the next century would require that we become a space-faring race. In an interview with Big Think, Hawking claimed the odds of humanity making it to the 22nd century was bad enough for a single-planet species, let alone the 31st:

“I believe that the long-term future of the human race must be in space. It will be difficult enough to avoid disaster on planet Earth in the next hundred years, let alone the next thousand, or million. The human race shouldn’t have all its eggs in one basket, or on one planet. Let’s hope we can avoid dropping the basket until we have spread the load.”

Artist concept of NASA’s Space Launch System (SLS) 70-metric-ton configuration launching to space. SLS will be the most powerful rocket ever built for deep space missions, including to an asteroid and ultimately to Mars. Credit: NASA/MSFC — *Hawking has repeatedly advocated space exploration and colonization as a way of ensuring humanity’s survival. Credit: NASA/MSFC*

But before anyone gets all gloomy, it should be noted that between our plans to colonize Mars, and the success of the Kepler mission, we have found hundreds of planets that could serve as potential homes for humanity. But as Hawking has stated in the past, we will need at least 100 years to develop all the necessary technologies to build colonies on even the closest of these planets (Mars).

Beyond our survival as a species, Professor Hawking also advocates space travel as a way of improving humanity’s understanding of itself. This was made evident in a direct quote that the Union live-tweeted during the speech, in which he said: “We must continue exploring space in order to improve our knowledge of humanity. We must go beyond our humble planet.”

And as he has done so often before, Hawking ended his speech on an optimistic note. According to the Independent, he wrapped up his Oxford lecture with the following words of advice:

“Remember to look up at the stars and not down at your feet. Try to make sense of what you see, wonder about what makes the universe exist. Be curious. However difficult life may seem, there is always something you can do and succeed at. It matters that you don’t just give up.”

It seems we have our work cut out for us. Extra-terrestrial and/or extra-solar colonies by 3016… or bust!

Further Reading: Oxford Mail, CS Monitor, Independent

November 19, 2016November 26, 2016 by Matt Williams

This Star Is The Roundest Natural Object Ever Seen

The star Kepler 11145123 is the roundest natural object ever measured in the universe, with a difference of just 3 km between the radius at the equator and the poles. Credit and ©: Mark A. Garlick

At one time, scientists believed that the Earth, the Moon, and all the other planets in our Solar System were perfect spheres. The same held true for the Sun, which they considered to be the heavenly orb that was the source of all our warmth and energy. But as time and research showed, the Sun is far from perfect. In addition to sunspots and solar flares, the Sun is not completely spherical.

For some time, astronomers believed this was the case with other stars as well. Owing to a number of factors, all stars previously studied by astronomers appeared to experience some bulging at the equator (i.e. oblateness). However, in a study published by a team of international astronomers, it now appears that a slowly rotating star located 5000 light years away is as close to spherical as we’ve ever seen!

Until now, observation of stars has been confined to only a few of the fastest-rotating nearby stars, and was only possible through interferometry. This technique, which is typically used by astronomers to obtain stellar size estimates, relies on multiple small telescopes obtaining electromagnetic readings on a star. This information is then combined to create a higher-resolution image that would be obtained by a large telescope.

Artist's impression of a white dwarf star in orbit around Sirius (a white supergiant). Credit: NASA, ESA and G. Bacon (STScI) — *Artist’s impression of a Sirius, an A-type Main Sequence White star. Credit: NASA, ESA and G. Bacon (STScI)*

However, by conducting asteroseismic measurements of a nearby star, a team of astronomers – from the Max Planck Institute, the University of Tokyo, and New York University Abu Dhabi (NYUAD) – were able to get a much more precise idea of its shape. Their results were published in a study titled “Shape of a Slowly Rotating Star Measured by Asteroseismology“, which recently appeared in the American Association for the Advancement of Science.

Laurent Gizon, a researcher with the Max Planck Institute, was the lead authjor on the paper. As he explained their research methodology to Universe Today via email:

“The new method that we propose in this paper to measure stellar shapes, asteroseismology, can be several orders of magnitude more precise than optical interferometry. It applies only to stars that oscillate in long-lived non-radial modes. The ultimate precision of the method is given by the precision on the measurement of the frequencies of the modes of oscillation. The longer the observation duration (four years in the case of Kepler), the better the precision on the mode frequencies. In the case of KIC 11145123 the most precise mode frequencies can be determined to one part in 10,000,000. Hence the astonishing precision of asteroseismology.”

Located 5000 light years away from Earth, KIC 11145123 was considered a perfect candidate for this method. For one, Kepler 11145123 is a hot and luminous, over twice the size of our Sun, and rotates with a period of 100 days. Its oscillations are also long-lived, and correspond directly to fluctuations in its brightness. Using data obtained by NASA’s Kepler mission over a more than four year period, the team was able to get very accurate shape estimates.

The variations in brightness can be interpreted as vibrations, or oscillations within the stars, using a technique called asteroseismology. The oscillations reveal information about the internal structure of the stars, in much the same way that seismologists use earthquakes to probe the Earth's interior. Credit: Kepler Astroseismology team. — *The variations in brightness can be interpreted as vibrations, or oscillations within the stars, using a technique called asteroseismology. Credit: Kepler Astroseismology team.*

“We compared the frequencies of the modes of oscillation that are more sensitive to the low-latitude regions of the star to the frequencies of the modes that are more sensitive to higher latitudes,” said Gizon. “This comparison showed that the difference in radius between the equator and the poles is only 3 km with a precision of 1 km. This makes Kepler 11145123 the roundest natural object ever measured, it is even more round than the Sun.”

For comparison, our Sun has a rotational period of about 25 days, and the difference between its polar and equatorial radii is about 10 km. And on Earth, which has a rotational period of less than a day (23 hours 56 minutes and 4.1 seconds), there is a difference of over 23 km (14.3 miles) between its polar and equator. The reason for this considerable difference is something of a mystery.

In the past, astronomers have found that the shape of a star can come down to multiple factors – such as their rotational velocity, magnetic fields, thermal asphericities, large-scale flows, strong stellar winds, or the gravitational influence of stellar companions or giant planets. Ergo, measuring the “asphericity” (i.e. the degree to which a star is NOT a sphere) can tell astronomers much about the star structures and its system of planets.

Ordinarily, rotational velocity has been seen to have a direct bearing on the stars asphericity – i.e. the faster it rotates, the more oblate it is. However, when looking at data obtained by the Kepler probe over a period of four years, they noticed that its oblateness was only a third of what they expected, given its rotational velocity.

Laurent Gizon, the lead researcher of the study, pictured comparing images of our Sun and Kepler 11145123. Credit: Max Planck Institute for Solar System Research, Germany. — *Laurent Gizon, the lead researcher of the study, pictured with asteroseismic readings of Kepler 11145123. Credit: Max Planck Institute for Solar System Research, Germany.*

As such, they were forced to conclude that something else was responsible for the star’s highly spherical shape. “”We propose that the presence of a magnetic field at low latitudes could make the star look more spherical to the stellar oscillations,” said Gizon. “It is known in solar physics that acoustic waves propagate faster in magnetic regions.”

Looking to the future, Gizon and his colleagues hope to examine other stars like Kepler 11145123. In our Galaxy alone, there are many stars who’s oscillations can be accurately measured by observing changes in their brightness. As such, the international team hopes to apply their asteroseismology method to other stars observed by Kepler, as well as upcoming missions like TESS and PLATO.

“Just like helioseismology can be used to study the Sun’s magnetic field, asteroseismology can be used to study magnetism on distant stars,” Gizon added. “This is the main message of this study.”

Further Reading: ScienceMag, Max Planck Institute

November 18, 2016November 26, 2016 by Nancy Atkinson

Soar Over Ceres With New Images From the Dawn Spacecraft

This image of the limb of dwarf planet Ceres shows a section of the northern hemisphere. Prominently featured is Occator Crater, home of Ceres' intriguing brightest areas. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

There’s one thing that could mean the end of the Dawn mission: if the hydrazine fuel for its maneuvering thruster system runs out. Now, engineers for the Dawn mission have figured out a way to save on this fuel while still sending Dawn to a new science orbit around the dwarf planet Ceres. They are effectively extending the mission while expanding on the science Dawn can do.

And in the meantime, Dawn’s cameras can take stunning new images, like the one above of Occator Crater on Ceres and its intriguing, mysterious bright regions.

“This image captures the wonder of soaring above this fascinating, unique world that Dawn is the first to explore,” said Marc Rayman, Dawn’s chief engineer and mission director at the Jet Propulsion Laboratory.

This image has the cameras on the Dawn spacecraft looking straight down at Occator Crater on Ceres, with its signature bright areas. Dawn scientists have found that the central bright spot, which harbors the brightest material on Ceres, contains a variety of salts. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

Dawn started making its way to a sixth science orbit earlier this month, raising its orbital height to over 4,500 miles (7,200 kilometers) from Ceres. For previous changes in its orbit, Dawn needed to make several changes in direction while it spiraled either higher or lower. But Dawn’s ever-ingenious engineers have figured out a way for the spacecraft to arrive at this next orbit while the ion engine thrusts in the same direction that Dawn is already going. This uses less hydrazine and xenon fuel than Dawn’s normal spiral maneuvers.

Previously, Dawn’s engineers have done things nothing short of miraculous, such as figuring out how to operate the spacecraft with only two reaction wheels (when at least three are needed, normally), they have developed new, emergency flight paths on short notice, and they keep figuring out ways to conserve the hydrazine. Earlier in the mission, they analyzed more than 50 different options to figure out how to reduce their fuel usage by a whopping 65 percent.

Occator Crater, with its central bright region and other reflective areas, provides evidence of recent geologic activity. The latest research suggests that the bright material in this crater is comprised of salts left behind after a briny liquid emerged from below, froze and then sublimated, meaning it turned from ice into vapor.

The impact that formed the crater millions of years ago unearthed material that blanketed the area outside the crater, and may have triggered the upwelling of salty liquid.

Another new image from Dawn scientists at the German Aerospace Center in Berlin shows how the dwarf planet’s colors would appear to the human eye. The color was calculated based on the way Ceres reflects different wavelengths of light.

This image of Ceres approximates how the dwarf planet's colors would appear to the eye. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA — This image of Ceres approximates how the dwarf planet’s colors would appear to the eye. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

Dawn scientists say that one goal of Dawn’s sixth science orbit is to refine previously collected measurements. The spacecraft’s gamma ray and neutron spectrometer, which has been investigating the composition of Ceres’ surface, will characterize the radiation from cosmic rays unrelated to Ceres. This will allow scientists to subtract “noise” from measurements of Ceres, making the information more precise.

This image of the limb of dwarf planet Ceres shows a section of the northern hemisphere. A shadowy portion of Occator Crater can be seen at the lower right -- its bright "spot" areas are outside of the frame of view. Part of Kaikara Crater (45 miles, 72 kilometers in diameter) is visible at top left. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA — This image of the limb of dwarf planet Ceres shows a section of the northern hemisphere. A shadowy portion of Occator Crater can be seen at the lower right — its bright “spot” areas are outside of the frame of view. Part of Kaikara Crater (45 miles, 72 kilometers in diameter) is visible at top left. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

The spacecraft has gathered tens of thousands of images and other information from Ceres since arriving in orbit on March 6, 2015. After spending more than eight months studying Ceres at an altitude of about 240 miles (385 kilometers), closer than the International Space Station is to Earth, Dawn headed for a higher vantage point in August. Then, in October, Dawn raised its orbit to about 920-mile (1,480 km) altitude, returning more images and other valuable data about Ceres.

Thanks to the ingenuity of Dawn’s engineers, we’ll have more time to study Ceres.

See all of Dawn’s latest images here.

Oxo Crater and its surroundings are featured in this image of Ceres' surface from NASA's Dawn spacecraft. Dawn took this image on Oct. 18, 2016, from its second extended-mission science orbit (XMO2), at a distance of about 920 miles (1,480 kilometers) above the surface. The image resolution is about 460 feet (140 meters) per pixel. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA — Oxo Crater and its surroundings are featured in this image of Ceres’ surface from NASA’s Dawn spacecraft. Dawn took this image on Oct. 18, 2016, from its second extended-mission science orbit (XMO2), at a distance of about 920 miles (1,480 kilometers) above the surface. The image resolution is about 460 feet (140 meters) per pixel. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

This view from NASA's Dawn spacecraft features a lobe-shaped flow feature in Ghanan Crater on Ceres. The flow feature is a place where a crater rim has collapse and material has flowed across the surface. Several small craters are visible on top of the flow; the number of craters can help scientists estimate the feature's age. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA — This view from NASA’s Dawn spacecraft features a lobe-shaped flow feature in Ghanan Crater on Ceres. The flow feature is a place where a crater rim has collapse and material has flowed across the surface. Several small craters are visible on top of the flow; the number of craters can help scientists estimate the feature’s age. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

Source: JPL

November 18, 2016November 26, 2016 by Evan Gough

Mars Has Features That Look Very Similar To Life Bearing Hot Springs On Earth

Rock formations near hot spring discharge channels at El Tatio, Chile, shown in this image, bear a striking resemblance to formations in the Gusev Crater on Mars. Image: Steven W. Ruff, Jack D. Farmer

A type of rock formation found on Mars may be some of the best evidence yet for life on that planet, according to a new study at Nature.com. The formations in question are in the Gusev Crater. When Spirit examined the spectra of the formations, scientists found that they closely match those of formations at El Tatio in Northern Chile.

The significance of that match? The El Tatio formations were produced by a combination of living and non-living processes.

The Gusev Crater geo-located on a map of Mars. Image: Wikimedia Labs

The Gusev Crater is a large crater that formed 3 to 4 billion years ago. It’s an old crater lake bed, with sediments up to 3,000 feet thick. Gusev also has exposed rock formations which show evidence of layering. A system of water channels called Ma’adim Vallis flows into Gusev, which could account for the deep sediments.

When it comes to evidence for the existence of life on Mars, and on early Earth, researchers often focus on hydrothermal spring deposits. These deposits can capture and preserve the biosignatures of early life. You can’t find evidence of ancient life just anywhere because geologic processes erase it. This is why El Tatio has received so much attention.

It’s also why formations at Gusev have received attention. They appear to have a hydrothermal origin as well. Their relation to the rocks around them support their hydrothermal origin.

El Tatio in Chile is a hard-to-find combination of extremely high UV, low rainfall, high annual evaporation rate, and high elevation. This makes it an excellent analog for Mars.

The Mars-like conditions at El Tatio make it rather unique on Earth, and that uniqueness is reflected in the rock deposits and structures that it produces. The most unique ones may be the biomediated silica structures that resemble the structures in Gusev. This resemblance suggest that they have the same causes: hydrothermal vents and biofilms.

Silica structures at the Gusev Crater (left) closely resemble the silica structures at El Tatio (right.) Image: Steven W. Ruff, Jack D. Farmer

Biomediated Structures?

The rock structures at El Tatio are typically covered with very shallow water that supports bio-films and mats comprised of different diatoms and cyanobacteria. The size and shape of the structures varies, probably according to the variable depth, flow velocity, and flow direction of the water. The same variations are present at Gusev on Mars. This begs the question, “Could the structures at Gusev also have a biological cause?”

Microscopic images of structures at El Tatio. B, in the upper right, shows the biofilm community partly responsible for the formation of the structures. The surface biofilm community includes silica-encrusted microbial filaments and sheaths, and spindle-shaped diatoms (white arrows.) Image: Steven W. Ruff, Jack D. Farmer.

Luckily, we have a rover on Mars that can probe the Gusev formations more deeply. Spirit used its Miniature Thermal Emission Spectrometer (Mini-TES) to obtain spectra of the Gusev formations. These spectra confirmed the similarity to the terrestrial formations at El Tatio.

Spirit was helpful in other ways. The rover has one inoperable wheel, which drags across the Martian surface, disrupting and overturning rock structures. Spirit was intentionally driven across the Gusev formations, in order to overturn and expose fragments. Then, Spirit’s Microscopic Imager was trained on those fragments.

(A) shows the wheel marks left by Spirit. The darker ones on the right are from the inoperable wheel. (B) is a closeup of the box in (A). (C) shows some of the rover tracks and features in Gusev. (D) shows two whitish rocks, intentionally overturned by Spirit's busted wheel. Image: NASA/JPL/Spirit PanCam. — (A) shows the wheel marks left by Spirit. The darker ones on the right are from the inoperable wheel. (B) is a closeup of the box in (A). (C) shows some of the rover tracks and features in Gusev. (D) shows two whitish rocks, intentionally overturned by Spirit’s busted wheel. Image: NASA/JPL/Spirit PanCam.

MM scale close-up images of the Martian rocks, on the left, show many similarities with the El Tatio rocks, right. Images: Steven W. Ruff, Jack D. Farmer, NASA/JPL.

Unfortunately, Spirit lacks the instrumentation to look deeply into the internal microscale features of the Martian rocks. If Spirit could do that, we would be much more certain that the Martian rocks were partly biogenic in origin. All of the surrounding factors suggest that they do, but that’s not enough to come to that conclusion.

This study presents more compelling evidence that there was indeed life on Mars at some point. But it’s not conclusive.

November 16, 2016November 26, 2016 by Bob King

New Theory of Gravity Does Away With Need for Dark Matter

Erik Verlinde explains his new view of gravity

Let’s be honest. Dark matter’s a pain in the butt. Astronomers have gone to great lengths to explain why is must exist and exist in huge quantities, yet it remains hidden. Unknown. Emitting no visible energy yet apparently strong enough to keep galaxies in clusters from busting free like wild horses, it’s everywhere in vast quantities. What is the stuff – axions, WIMPS, gravitinos, Kaluza Klein particles?

Estimated distribution of matter and energy in the universe. Credit: NASA

It’s estimated that 27% of all the matter in the universe is invisible, while everything from PB&J sandwiches to quasars accounts for just 4.9%. But a new theory of gravity proposed by theoretical physicist Erik Verlinde of the University of Amsterdam found out a way to dispense with the pesky stuff.

formation of complex symmetrical and fractal patterns in snowflakes exemplifies emergence in a physical system. — Snowflakes exemplify the concept of emergence with their complex symmetrical and fractal patterns created when much simpler pieces join together. Credit: Bob King

Unlike the traditional view of gravity as a fundamental force of nature, Verlinde sees it as an emergent property of space. Emergence is a process where nature builds something large using small, simple pieces such that the final creation exhibits properties that the smaller bits don’t. Take a snowflake. The complex symmetry of a snowflake begins when a water droplet freezes onto a tiny dust particle. As the growing flake falls, water vapor freezes onto this original crystal, naturally arranging itself into a hexagonal (six-sided) structure of great beauty. The sensation of temperature is another emergent phenomenon, arising from the motion of molecules and atoms.

So too with gravity, which according to Verlinde, emerges from entropy. We all know about entropy and messy bedrooms, but it’s a bit more subtle than that. Entropy is a measure of disorder in a system or put another way, the number of different microscopic states a system can be in. One of the coolest descriptions of entropy I’ve heard has to do with the heat our bodies radiate. As that energy dissipates in the air, it creates a more disordered state around us while at the same time decreasing our own personal entropy to ensure our survival. If we didn’t get rid of body heat, we would eventually become disorganized (overheat!) and die.

The more massive the object, the more it distorts spacetime. Credit: LIGO/T. Pyle — The more massive the object, the more it distorts space-time, shown here as the green mesh. Earth orbits the Sun by rolling around the dip created by the Sun’s mass in the fabric of space-time. It doesn’t fall into the Sun because it also possesses forward momentum. Credit: LIGO/T. Pyle

Emergent or entropic gravity, as the new theory is called, predicts the exact same deviation in the rotation rates of stars in galaxies currently attributed to dark matter. Gravity emerges in Verlinde’s view from changes in fundamental bits of information stored in the structure of space-time, that four-dimensional continuum revealed by Einstein’s general theory of relativity. In a word, gravity is a consequence of entropy and not a fundamental force.

Space-time, comprised of the three familiar dimensions in addition to time, is flexible. Mass warps the 4-D fabric into hills and valleys that direct the motion of smaller objects nearby. The Sun doesn’t so much “pull” on the Earth as envisaged by Isaac Newton but creates a great pucker in space-time that Earth rolls around in.

In a 2010 article, Verlinde showed how Newton’s law of gravity, which describes everything from how apples fall from trees to little galaxies orbiting big galaxies, derives from these underlying microscopic building blocks.

His latest paper, titled Emergent Gravity and the Dark Universe, delves into dark energy’s contribution to the mix. The entropy associated with dark energy, a still-unknown form of energy responsible for the accelerating expansion of the universe, turns the geometry of spacetime into an elastic medium.

“We find that the elastic response of this ‘dark energy’ medium takes the form of an extra ‘dark’ gravitational force that appears to be due to ‘dark matter’,” writes Verlinde. “So the observed dark matter phenomena is a remnant, a memory effect, of the emergence of spacetime together with the ordinary matter in it.”

Rotation curve of the typical spiral galaxy M 33 (yellow and blue points with errorbars) and the predicted one from distribution of the visible matter (white line). The discrepancy between the two curves is accounted for by adding a dark matter halo surrounding the galaxy. Credit: Public domain / Wikipedia — This diagram shows rotation curves of stars in M33, a typical spiral galaxy. The vertical scale is speed and the horizontal is distance from the galaxy’s nucleus. Normally, we expect stars to slow down the farther they are from galactic center (bottom curve), but in fact they revolve much faster (top curve). The discrepancy between the two curves is accounted for by adding a dark matter halo surrounding the galaxy. Credit: Public domain / Wikipedia

I’ll be the first one to say how complex Verlinde’s concept is, wrapped in arcane entanglement entropy, tensor fields and the holographic principal, but the basic idea, that gravity is not a fundamental force, makes for a fascinating new way to look at an old face.

Physicists have tried for decades to reconcile gravity with quantum physics with little success. And while Verlinde’s theory should be rightly be taken with a grain of salt, he may offer a way to combine the two disciplines into a single narrative that describes how everything from falling apples to black holes are connected in one coherent theory.

November 16, 2016November 19, 2016 by Matt Williams

NASA Stands Ready For Trump Transition Team

President Obama meeting with President-elect Donald Trump to discuss the transition of power. Credit: whitehouse.gov

For almost a week now, NASA has been preparing for the transition between the Obama administration and that o Donald Trump, the president-elect. Unfortunately, little seems clear at this point, as the Trump campaign has yet to send representatives to speak to them, or give any indication of what the future budget environment might look like.

In lieu of clear statements, speculation has been the norm, and has been based almost entirely on statements made during the election. And with many important missions approaching, NASA has been understandably antsy. Luckily, with the appointment of a Agency Research Team (ART), it appears that the much-needed meeting may be on the way.

This news is certainly a welcome relief in a post-election atmosphere characterized for the most part by uncertainty and ambiguity. And it certainly is good news for NASA administrators, who have been getting increasingly anxious about what the new administration’s policies will mean for their future.

Artist's conception of NASA's Space Launch System with Orion crewed deep space capsule. Credit: NASA — *Artist’s conception of NASA’s Space Launch System (SLS) with the Orion crewed deep space capsule. Credit: NASA*

As Greg Williams – the Deputy Associate Administrator for Policy and Plans at NASA’s Human Exploration and Operations Mission Directorate – was quoted as saying this past Monday (Nov. 14th):

“The new administration has not yet named its transition team members that interface with NASA, so we don’t yet know who we’ll be talking to. We are prepared to talk with them when they arrive… We hope to be building on the consensus we’ve achieved on the phases of exploration, the progression of human exploration from the ISS all the way to the surface of Mars.”

Once the election wrapped up after Nov. 8th, it was rumored that Mark Albrecht – the former executive secretary of the National Space Council during George H.W. Bush’s presidency – would be leading the NASA transition efforts. However, these rumors were not followed by any formal announcement, and no other individuals were named to the team.

This was certainly disconcerting, since NASA and other large agencies are used to meeting with transitional teams within days of an election. This is seen as essential for ensuring that there is continuity, or that they are apprised of changes long before they take effect. Given the nature of their work, NASA planners need to know in advance what kind of budgets they will have to work with, since it will determine what missions they can do.

NASA's Journey to Mars. NASA is developing the capabilities needed to send humans to an asteroid by 2025 and Mars in the 2030s. Credit: NASA/JPL — NASA’s Journey to Mars. NASA is developing the capabilities needed to send humans to an asteroid by 2025 and Mars in the 2030s. Credit: NASA/JPL

As Williams indicated, NASA is particularly concerned about their “Journey to Mars“, a long-term goal which requires a consistent commitment in terms of financial resources. And while transitional funding was made available for fiscal year 2017 – thanks to the NASA Transition Authorization Act of 2016 – NASA is looking far beyond the coming year.

In the coming years, NASA will need a solid commitment from the Trump presidency to ensure the completion and testing of the Space Launch System (SLS) – the successor to the Space Shuttle Program. They also require a multi-billion dollar commitment to continue testing the Orion Multipurpose Crew Vehicle, not to mention the several crewed missions they hope to conduct using both.

Another thing that is central to mounting a crewed mission to Mars in the 2030s are the ongoing studies aboard the ISS. In particular, NASA hopes to use long-duration stays aboard the station to determine the risks to astronaut health. A crewed mission to Mars will spend several months in space, during which time they will be living in zero-gravity conditions and exposed to a great deal of radiation.

In addition, NASA hopes to mount a crewed mission to an asteroid in the coming decade. The plan entails sending a robotic spacecraft to capture and tow a Near-Earth Object (NEO) into lunar orbit – known as the Asteroid Robotic Redirect Missions (ARRM). This is to be followed by a crewed Orion spacecraft being sent to explore the asteroid, which will develop key systems and expertise for the coming mission to Mars.

NASA's new budget could mean the end of their Asteroid Redirect Mission. Image: NASA (Artist's illustration) — NASA’s new budget could mean the end of their Asteroid Redirect Mission. Image: NASA (Artist’s illustration)

Unfortunately, the Transition Authorization Act contained some strongly-worded language about the robotic asteroid mission. Essentially, it was deemed as not falling within the original budget constraints of $1.25 billion (it is now estimated at $1.4 billion). NASA planners were therefore encouraged to find “a more cost effective and scientifically beneficial means to demonstrate the technologies needed for a human mission to Mars.”

As such, NASA is very interested to know if the new administration will make the necessary commitment to fund the ARRM, or if they need to scrub it at this point and go back to the drawing board. One way or another, NASA needs to know what it will be capable of doing in the coming years so that they can develop a plan for what they intend to do.

The current state of uncertainty has been largely attributed to the fact that the Trump campaign engaged in little planning before the election. While various statements were made about the important role NASA plays, nothing concrete was laid out. And Trump even went so far as to say that long-term exploration goals would depend upon the economic climate.

One can only hope that the new Agency Research Team will have an agenda prepared when they meet with NASA administrators. We can also hope that it won’t impede NASA’s more ambitious efforts for the coming years. The agency has made it clear that its plans to explore Mars are in keeping with the goal of remaining the leader in the field of space exploration and research. If they can’t get there in the time period desired, someone else just might!

Further Reading: Space News

November 15, 2016November 26, 2016 by Matt Williams

A New Prototype Telescope Proves Itself Worthy

The Cherenkov Telescope Array prototype, located at the Serra La Nave observing stationon Mount Etna, Sicily. Credit: cta-observatory.org

In 2013, the Cherenkov Telescope Array (CTA) was established with the intention of building the world’s largest and most sensitive high-energy gamma ray observatory. Consisting of over 1350 scientists from 210 research institutes in 32 countries, this observatory will use 100 telescopes across the northern and southern hemispheres to explore the high-energy Universe.

Key to their efforts is a prototype dual-mirror Schwarzschild-Couder telescope, known as the Astrofisica con Specchi a Tecnologia Replicante Italiana (ASTRI). Since it was first created in 2014, this prototype has been undergoing tests at the Serra La Nave Observing Station on Mount Etna, Sicily. And as of October of 2016, it passed its most important test to date, demonstrating a constant point-spread function across its full field of view.

The ASTRI telescope is essentially a revolutionary kind of Imaging Atmospheric Cherenkov Telescope (IACT). These ground-based telescopes are used by astronomers to detect cosmic high-energy gamma rays. These rays are produced by the most energetic objects in the universe (i.e. pulsars, supernovae, regions around black holes), and are only detectable because of the Cherenkov Effect, which they undergo once they pass into our atmosphere.

*A IACT telescope at the Whipple Observatory, Mount Hopkins, Arizona. Credit: magic.mpp.mpg.de*

This effect occurs when particles of light achieve speeds greater than the phase velocity of light in their particular medium. In this case, the effect is produced when light particles pass from the vacuum of space into our atmosphere, temporarily exceeding the speed of light in air and producing a glow in the blue to UV range. In the case of very-high-energy gamma rays, indirect observations of this Cherenkov radiation is the only way to detect them.

Typically, Cherenkov telescopes use a mirror to collect light and focus it on a camera. The ASTRI telescope is something quite different, in that it is based on the Schwarzschild-Couder model. As Giovanni Pareschi, an astronomer at the INAF-Brera Astronomical Observatory and the principal investigator of the ASTRI project, told Universe Today via email:

“The ASTRI telescope for the first time is based on a two mirror imaging configuration (while in general Cherenkov telescopes work with in single mirror configuration, i.e. just a big primary mirror with the camera put in the Newtonian focus and a f-number close to 1). ASTRI is a prototype of the telescopes of the Small Size Telescope sub-array of the CTA Observatory. The sub-array is devoted to detect the gamma rays with the highest energy (up to 100 Tev). In order to properly work, the sub-array has to be based on a large number of telescopes (70 units) with a distance from each other of a 250 m distributed and with a large field (10 deg x 10 deg) of view with a constant angular resolution of a few arc minutes across the field of view.

This idea for such a telescope was first proposed in 1905 by German astronomer Karl Schwarzschild, but remained dormant for almost a century since it was deemed too difficult and too expensive to construct. It was not until 2007 that it was considered as a viable means for creating a new type of IACT. And in 2014, the INAF-Brera Astronomical Observatory commissioned the first of its kind to be built.

*Polaris, the North Star, as observed by ASTRI with different offsets from the optical axis of the telescope. Credits: Enrico Giro/Rodolfo Canestrari/Salvo Scuderi/Giorgia Sironi/INAF*

“[W]e have for the first time adopted a two reflection design based on the Schwarzschild-Couder configuration never realized before (also for telescopes operating in the visible band),” added Pareschi. “This configuration allows us to optimize the angular resolution across the field of view and to use focal plane cameras of small dimensions (thanks to this property, we could use new solid-state technology based Silicon photomultiplier sensors instead of the “old” classical photomultiplier tubes used so far in Cherenkov astronomy).”

These advantages, and the advances they allow for, will make ASTRI telescope approximately ten times more sensitive than current instruments. And with this latest test – which demonstrating a constant point-spread function of a few arc minutes over a large field of view of 10 degrees – the team behind it now has proof that it will work. As Pareschi explained:

“The test demonstrated for the first time that a telescope based on the Schwarzschild-Couder configuration correctly works and that a two-mirror configuration can be adopted for making Cherenkov telescopes for gamma ray astronomy. In addition, the ASTRI prototype has been completely characterized and validated from the opto-mechanical point of view, demonstrating that we can now proceed with the construction of the Small-Sized Telescopes (SSTs) of the array based on the ASTRI design.”

With this important test complete, the INAF-Brera team hopes to spend the next few months prepping the telescope. This will include mounting the Cherenkov camera onto the prototype and testing its gamma-ray performance. Then they will start to produce the first set of ASTRI telescopes to create a mini-array, which will serve as a precursor to the planned CTA sub-array that is scheduled to be built in Chile.

*Artist’s impression of a gamma-ray burst. Credit: ESO/A. Roquette*

Once the camera is tested and mounted, the ASTRI team will conduct their first observations of gamma-rays at very high energies. These observations will allow scientists to determine the direction of gamma-ray photons that are the result of celestial sources, such as neutron stars, pulsars, supernovae, and black holes, tracing them back to their respective sources.

And with the planned construction of 100 SSTs to be spread out over the northern and southern hemispheres, the CTA array will outnumber all other telescopes in the world. The wide coverage and large number of these telescopes, spread over a wide area, will improve astronomers chances of detecting very high-energy gamma rays as they pass into our atmosphere.

Further Reading: CTA

November 10, 2016November 21, 2016 by Matt Williams

Was Physics Really Violated By EM Drive In “Leaked” NASA Paper?

A model of the EmDrive, by NASA/Eagleworks. Credit: NASA Spaceflight Forum/emdrive.com

Ever since NASA announced that they had created a prototype of the controversial Radio Frequency Resonant Cavity Thruster (aka. the EM Drive), any and all reported results have been the subject of controversy. And with most of the announcements taking the form of “leaks” and rumors, all reported developments have been naturally treated with skepticism.

And yet, the reports keep coming. The latest alleged results come from the Eagleworks Laboratories at the Johnson Space Center, where a “leaked” report revealed that the controversial drive is capable of generating thrust in a vacuum. Much like the critical peer-review process, whether or not the engine can pass muster in space has been a lingering issue for some time.

Given the advantages of the EM Drive, it is understandable that people want to see it work. Theoretically, these include the ability to generate enough thrust to fly to the Moon in just four hours, to Mars in 70 days, and to Pluto in 18 months, and the ability to do it all without the need for propellant. Unfortunately, the drive system is based on principles that violate the Conservation of Momentum law.

Aerial Photography of Johnson Space Center site and facilities. Credit: NASA/James Blair — *Aerial photograph of NASA’s Johnson Space Center, where the Eagleworks Laboratory is located. Credit: NASA/James Blair*

This law states that within a system, the amount of momentum remains constant and is neither created nor destroyed, but only changes through the action of forces. Since the EM Drive involves electromagnetic microwave cavities converting electrical energy directly into thrust, it has no reaction mass. It is therefore “impossible”, as far as conventional physics go.

The report, titled “Measurement of Impulsive Thrust from a Closed Radio Frequency Cavity in Vacuum“, was apparently leaked in early November. It’s lead author is predictably Harold White, the Advanced Propulsion Team Lead for the NASA Engineering Directorate and the Principal Investigator for NASA’s Eagleworks lab.

As he and his colleagues (allegedly) report in the paper, they completed an impulsive thrust test on a “tapered RF test article”. This consisted of a forward and reverse thrust phase, a low thrust pendulum, and three thrust tests at power levels of 40, 60 and 80 watts. As they stated in the report:

“It is shown here that a dielectrically loaded tapered RF test article excited in the TM212 mode at 1,937 MHz is capable of consistently generating force at a thrust level of 1.2 ± 0.1 mN/kW with the force directed to the narrow end under vacuum conditions.”

Ionic propulsion is currently the slowest, but fmost fuel-efficient, form of space travel. Credit: NASA/JPL — *Ionic propulsion is currently the slowest, but most fuel-efficient, form of space travel. Credit: NASA/JPL*

To be clear, this level of thrust to power – 1.2. millinewtons per kilowatt – is quite insignificant. In fact, the paper goes on to place these results in context, comparing them to ion thrusters and laser sail proposals:

“The current state of the art thrust to power for a Hall thruster is on the order of 60 mN/kW. This is an order of magnitude higher than the test article evaluated during the course of this vacuum campaign… The 1.2 mN/kW performance parameter is two orders of magnitude higher than other forms of ‘zero propellant’ propulsion such as light sails, laser propulsion and photon rockets having thrust to power levels in the 3.33-6.67 [micronewton]/kW (or 0.0033 – 0.0067 mN/kW) range.”

Currently, ion engines are considered the most fuel-efficient form of propulsion. However, they are notoriously slow compared to conventional, solid-propellant thrusters. To offer some perspective, NASA’s Dawn mission relied on a xenon-ion engine that had a thrust to power generation of 90 millinewtons per kilowatt. Using this technology, it took the probe almost four years to travel from Earth to the asteroid Vesta.

The concept of direct-energy (aka. laser sails), by contrast, requires very little thrust since it involves wafer-sized craft – tiny probes which weight about a gram and carry all their instruments they need in the form of chips. This concept is currently being explored for the sake of making the journey to neighboring planets and star systems within our own lifetimes.

Two good examples are the NASA-funded DEEP-IN interstellar concept that is being developed at UCSB, which attempts to use lasers to power a craft up to 0.25 the speed of light. Meanwhile, Project Starshot (part of Breakthrough Initiatives) is developing a craft which they claim will reach speeds of 20% the speed of light, and thus be able to make the trip to Alpha Centauri in 20 years.

Compared to these proposals, the EM Drive can still boast the fact that it does not require any propellant or an external power source. But based on these test results, the amount of power that would be needed to generate a significant amount of thrust would make it impractical. However, one should keep in mind that this low power test was designed to see if any thrust detected could be attributed to anomalies (none of which were detected).

The report also acknowledges that further testing will be necessary to rule out other possible causes, such as center of gravity (CG) shifts and thermal expansion. And if outside causes can again be ruled out, future tests will no doubt attempt to maximize performance to see just how much thrust the EM Drive is capable of generating.

But of course, this is all assuming that the “leaked” paper is genuine. Until NASA can confirm that these results are indeed real, the EM Drive will be stuck in controversy limbo. And while we’re waiting, check out this descriptive video by astronomer Scott Manley from the Armagh Observatory:

Further Reading: Science Alert