Comet 2012 S1 ISON in outburst, seen on November 15, 2013. Credit and copyright: Damian Peach.
Establishing a sustained human presence somewhere other than Earth is a vital part of humanity’s future, no matter what. We know that Earth won’t last forever. We don’t know exactly which one of the many threats that Earth faces will ultimately extinguish life here, but life will be extinguished completely at some future point.
Colonizing moons or planets is one way to do it. But that’s really hard. We may make it to Mars before too long, but we don’t know how successful we’ll be at establishing a presence there. There are an awful lot of ‘ifs’ when it comes to Mars.
The only other option is space habitats. That makes sense; there’s much more space out there than there is surface area on planets and moons. And space habitats have been on the minds of thinkers, writers, and scientists for a long time.
Gerard K. O’Neill is probably the most well-known thinker when it comes to space habitats. In 1977 he published the seminal book on space habitats, called “The High Frontier: Human Colonies in Space.” O’Neill in his time popularized what is now called the “O’Neill Cylinder.”
The O’Neill Cylinder
Interior view of an O’Neill Cylinder. There are alternating strips of livable surface and “windows” to let light in. Image: Rick Guidice, NASA Ames Research Center
The O’Neill Cylinder lay the groundwork for space habitat design. It consisted of two counter-rotating cylinders, one nested inside the other. The counter-rotation provided stability and gravity. The atmosphere would be controlled, and the habitat would be powered by solar, and perhaps fusion.
An illustration of two O’Neill Cylinder’s. Image: Rick Guidice NASA Ames Research Center
The McKendree Cylinder
Other designs from other people followed O’Neill’s. Notable among them is the McKendree Cylinder. The McKendree would be gargantuan compared to the O’Neill Cylinder. Thanks to carbon nanotubes, it would have more surface area than the United States. It was designed by NASA Engineer Tom McKendree and introduced in the year 2,000 at the NASA “Turning Goals into Reality Conference.”
There’ve been other ideas for massive, high-tech space habitats, including the Bernal Sphere and the Stanford Torus. All of these designs are typical of engineers and technologists. Lots of high-tech, lots of steel, lots of machinery. But the engineers and scientists behind those designs weren’t the only ones thinking about humans in space.
Carl Sagan was too. And he had a very different idea of what space habitats could be.
So Crazy It Just Might Work
But the craziest idea for space habitats has got to be Carl Sagan’s, from his 1985 book “Comet.”In “Comet” Sagan suggested that humans could seek refuge in, and even colonize, actual comets travelling through our Solar System. Using all the advanced technologies thought about in Sagan’s time—but which don’t exist yet—comets could be transformed into humanity’s salvation. His idea is a world apart from the high-tech, highly-engineered, gleaming habitat designs that most people think of when they think of space habitats.
I’m a fan of Sagan’s. Like many in my generation, I was influenced by his TV series Cosmos. I loved it and it’s stuck with me. His book “The Demon-Haunted World” taught us what scientific skepticism can be, and how useful it is.
“Comet” was published only months before Halley’s Comet arrived in our inner Solar System in 1986. Image: Jon Lomberg, Random House New York.
Sagan’s is the most surprising—and perhaps bleakest—view of space habitats. Life inside comets sounds shocking, and maybe even foolish, but as Sagan explains, there is some reasoning behind the idea.
Remember that when Sagan wrote about this, thermonuclear war between the superpowers was a “thing,” and thinkers like Sagan felt a sense of imminent danger. That sense of foreboding may have contributed to his “comets-as-space-habitas” idea. Plus, he was just an innovative thinker.
Carl Sagan in 1980.
Sagan’s thinking behind using comets as space habitats starts out something like this: if there are about a hundred thousand comets crossing Earth’s orbit, and another hundred trillion in the Oort Cloud, their combined surface area is roughly equal to about a hundred million Earths. And with advanced technology, Sagan proposed that these comets could be captured and colonized and sent on orbits and trajectories desirable to humans.
Comet Lovejoy and its spectacular “lively” ion tail photographed on January 8th by Nick Howes at Tzec Muan Network at Siding Spring Australia. Could Lovejoy and its brethren one day provide a home for humanity?
Comets are rich in minerals, water ice, and biological compounds. Or so it was thought at the time. That means raw material for manufacturing, water to drink and to supply oxygen, biological compounds for bio-engineering, and even the raw material for rocket fuel. Add a fusion reactor for power, and
comets could end up being the convenience stores of the Solar System.
Physicist Freeman Dyson, an innovative thinker himself, had something to add to Sagan’s comet idea. In “Comet,” Sagan tells of Dyson’s ideas around genetic engineering, and that one day we should be able to engineer forms of life that could thrive on comets, and meet some of our needs. Dyson talks about a giant, genetically engineered tree that could grow on a comet, planted in snow rich in organic chemicals. The tree would supply us with fresh oxygen.
The OSIRIS narrow-angle camera aboard the Rosetta spacecraft captured this image of comet 67P/Churyumov-Gerasimenko on September 30, 2016. Does it look habitable, or potentially habitable, to you? Credits: ESA/Rosetta/MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA
This sounds extremely far-fetched: humans living inside comets travelling through space, with giant genetically engineered trees and fusion power plants. I try to remind myself that many things we take for granted now were once thought to be laughable. But even though parts of the comet-as-space-habitat idea sound fanciful—like the giant tree—there may be the seed of a practical idea here, with humans hitching rides on comets, molding them to our purposes, and extracting resources like minerals and fuel from them.
High cliffs on the surface of Comet Churyumov–Gerasimenko as imaged by the Rosetta spacecraft. Image Credit & Licence (CC BY-SA 3.0 IGO): ESA, Rosetta spacecraft, NAVCAM; Additional Processing: Stuart Atkinson
Sagan was an agile creative thinker. He’s clearly riffing when he outlines his ideas for life on comets. He’s like the John Coltrane of space science.
It seems doubtful that we would go to the trouble to turn comets into actual habitats. It’s probably more science fiction that science. But the future is unwritten, and given enough time, almost anything might be possible.
Grand opening ceremony for the ‘Heroes and Legends’ attraction on Nov. 11, 2016 at the Kennedy Space Center Visitor Complex in Florida and attended by more than 25 veteran and current NASA astronauts. It includes the new home of the U.S. Astronaut Hall of Fame, presented by Boeing. In addition to displays honoring the 93 Americans currently enshrined in the hall, the facility looks back to the pioneering efforts of Mercury, Gemini and Apollo. It provides the background and context for space exploration and the legendary men and women who pioneered the nation's journey into space. Credit: Ken Kremer/kenkremer.com
Grand opening ceremony for the ‘Heroes and Legends’ attraction on Nov. 11, 2016 at the Kennedy Space Center Visitor Complex in Florida and attended by more than 25 veteran and current NASA astronauts. It includes the new home of the U.S. Astronaut Hall of Fame, presented by Boeing. In addition to displays honoring the 93 Americans currently enshrined in the hall, the facility looks back to the pioneering efforts of Mercury, Gemini and Apollo. It provides the background and context for space exploration and the legendary men and women who pioneered the nation’s journey into space. Credit: Ken Kremer/kenkremer.com
KENNEDY SPACE CENTER VISITOR COMPLEX, FL – America’s pioneering astronauts who braved the perils of the unknown and put their lives on the line at the dawn of the space age atop mighty rockets that propelled our hopes and dreams into the new frontier of outer space and culminated with NASA’s Apollo lunar landings, are being honored with the eye popping new ‘Heroes and Legends’ attraction at the Kennedy Space Center Visitor Complex (KSCVC) in Florida.
With fanfare and a fireworks display perfectly timed for Veterans Day, ‘Heroes and Legends’ opened its doors to the public on Friday, November 11, 2016, during a gala ceremony attended by more than 25 veteran and current NASA astronauts, including revered Gemini and Apollo space program astronauts Buzz Aldrin, Jim Lovell, Charlie Duke, Tom Stafford, Dave Scott, Walt Cunningham and Al Worden – and throngs of thrilled members of the general public who traveled here as eyewitnesses from all across the globe.
Aldrin, Scott, and Duke walked on the Moon during the Apollo 11, 15 and 16 missions.
Also on hand were the adult children of the late-astronauts Alan Shepard (first American in space) and Neil Armstrong (first man to walk on the Moon), as well as representatives from NASA, The Boeing Company (sponsor) and park operator Delaware North – for the engaging program hosted by Master of Ceremonies John Zarrella, CNN’s well known and now retired space correspondent.
Grand opening ceremony for the ‘Heroes and Legends’ attraction on Nov. 11, 2016 at the Kennedy Space Center Visitor Complex in Florida and attended by more than 25 veteran and current NASA astronauts. Credit: Ken Kremer/kenkremer.com
The stunning new ‘Heroes and Legends’ attraction is perfectly positioned just inside the entrance to the KSC Visitor Complex to greet visitors upon their arrival with an awe inspiring sense of what it was like to embark on the very first human journey’s into space by the pioneers who made it all possible ! And when every step along the way unveiled heretofore unknown treasures into the origin of us and our place in the Universe.
Upon entering the park visitors will immediately and surely be mesmerized by a gigantic bas relief sculpture recreating an iconic photo of America’s first astronauts – the Mercury 7 astronauts; Scott Carpenter, Gordon Cooper, John Glenn, Gus Grissom, Wally Schirra, Alan Shepard, and Deke Slayton.
“With all the drama of an actual trip to space, guests of Kennedy Space Center Visitor Complex in Florida will be greeted with a dramatic sense of arrival with the new Heroes & Legends featuring the U.S. Astronaut Hall of Fame® presented by Boeing. Positioned just inside the entrance, the attraction sets the stage for a richer park experience by providing the emotional background and context for space exploration and the legendary men and women who pioneered our journey into space,” according to a description from Delaware North Companies Parks and Resorts, which operates the KSC visitor complex.
“Designed to be the first stop upon entering Kennedy Space Center Visitor Complex, Heroes & Legends uses the early years of the space program to explore the concept of heroism, and the qualities that define the individuals who inspired their generation.”
Astronauts cut the ribbon during Grand opening ceremony for the ‘Heroes and Legends’ attraction on Nov. 11, 2016 at the Kennedy Space Center Visitor Complex in Florida, led by Kennedy Space Center Director Bob Cabana, a former space shuttle astronaut and member of the Astronaut Hall of Fame, during the ceremony. Credit: Julian Leek
“I hope that all of you, when you get to see Heroes and Legends, you’re inspired,” said Kennedy Space Center Director Bob Cabana, a former space shuttle astronaut and member of the Astronaut Hall of Fame, during the ceremony.
“The children today can see that there is so much more they can reach for if they apply themselves and do well.”
“I think people a thousand years from now are going to be happy to see these artifacts and relics,” Apollo 15 command module pilot Al Worden told the crowd.
“We have so much on display here with a Saturn V, Space Shuttle Atlantis. People will think back and see the wonderful days we had here. And I guess in that same vein, that makes me a relic too.”
Grand opening ceremony for the ‘Heroes and Legends’ attraction on Nov. 11, 2016 at the Kennedy Space Center Visitor Complex in Florida and attended by more than 25 veteran and current NASA astronauts. Credit: Julian Leek
Furthermore, ‘Heroes and Legends’ is now very conveniently housed inside the new home of the U.S. Astronaut Hall of Fame (AHOF) – making for a unified space exploration experience for park visitors. AHOF previously was located at another off site park facility some seven miles outside and west of the Visitor Complex.
The bas relief measures 30 feet tall and 40 feet wide. It is made put of fiberglass and was digitally sculpted, carved by CNC machines and juts out from the side of the new into the new 37,000 square foot U.S. Astronaut Hall of Fame (AHOF) structure.
To date 93 astronauts have been inducted into the Astronaut Hall of Fame spanning the Mercury, Gemini, Apollo and Space Shuttle programs.
“I don’t consider myself a hero like say, Charles Lindbergh,” said Jim Lovell, a member of the Astronaut Hall of Fame and Apollo 13 commander, when asked by Zarrella what it feels like to be considered an American space hero. “I just did what was proper and exciting — something for my country and my family. I guess I’m just a lucky guy.”
The astronauts are also quick to say that they were supported by hundreds of thousands of dedicated people working in the space program to make Apollo happen.
“It important to remember all the dedication and hard work that it took from those of us involved in the astronaut program, but also the support we received from Kennedy and all the contractors involved in Apollo,” said Apollo 16 moonwalker Charlie Duke.
“400,000 people made it possible for 24 of us to go to the Moon.”
“So dream big, aim high!” exclaimed Duke.
“Hopefully this is an inspiration to you and your kids and grandkids.”
Construction of the facility by Falcon’s Treehouse, an Orlando-based design firm began in the fall of 2015.
“We’re focusing on a story to create what we consider a ‘launch pad’ for our visitors,” said Therrin Protze, the Delaware North chief operating officer of the Visitor Complex. “This is an opportunity to learn about the amazing attributes of our heroes behind the historical events that have shaped the way we look at space, the world and the future.
“We are grateful to NASA for allowing us to tell the NASA story to millions of guests from all over the world,” Protze said.
Visitors walk up a sweeping ramp to enter the Heroes and Legends experience.
After visitors walk through the doors, they will be immersed by two successive video presentations and finally the Hall of Fame exhibit hall.
Here’s a detailed description:
• In the stunning 360-degree discovery bay, What is a Hero?, guests will explore how society defines heroism through diverse perspectives. Each examination of heroism starts with the following questions: What is a hero; Who are the heroes of our time; and What does it take to be a hero? During the seven-minute presentation, the historic beginning of the space race is acknowledged as the impetus for America’s push to the stars in NASA’s early years and the rivalry between the United States and the Soviet Union during the Cold War.
• Through the Eyes of a Hero is a custom-built theater featuring a multi-sensory experience during which guests will vicariously join NASA’s heroes and legends on the most perilous stages of their adventures. Artistically choreographed lighting and 3D imagery will be enhanced by intense, deeply resonant sound effects to create the sensation of being “in the moment.” The seven and one-half minute show takes guests on an intimate journey with four space-age heroes to fully immerse them in the awe, excitement and dangers of the first crewed space program missions.
• The third experience, A Hero Is…, offers interactive exhibits that highlight the nine different attributes of our history making astronauts: inspired, curious, passionate, tenacious, disciplined, confident, courageous, principled and selfless. A collection of nine exhibit modules will explore each aforementioned attribute, through the actual experiences of NASA’s astronauts. Their stories are enhanced with memorabilia from the astronaut or the space program.
A statue of astronaut Alan Shepard, America’s first person in space, stands just inside the doors to the U.S. Astronaut Hall of Fame. The exhibit is housed in a rotunda and connects the visitor to each of the astronaut inductees through state-of-the-art interactive technology. Credit: Lane Hermann
Priceless historic artifacts on display also include two flown capsules from Mercury and Gemini; the Sigma 7 Mercury spacecraft piloted by Wally Schirra during his six-orbit mission in October 1962 and the Gemini IX capsule flown by Tom Stafford and Gene Cernan for three days in June 1966.
The Sigma 7 Mercury spacecraft piloted by astronaut Wally Schirra during his nine-hour, 13-minute mission of six orbits on October 3, 1962 mated to a human rated Mercury Redstone rocket (MR-6) is on display in the Heroes and Legends display at the Kennedy Space Center Visitor Complex in Florida. Credit: Ken Kremer/kenkremer.com
The human rated Mercury Redstone-6 (MR-6) is also on display and dramatically mated to the Schirra’s Sigma 7 Mercury capsule.
Another room houses the original consoles of the Mercury Mission Control room with the world map that was used to follow the path of John Glenn’s Mercury capsule Friendship 7 between tracking stations when he became the first American to orbit Earth in 1962.
Interactive features in the KSCVC Heroes and Legends attraction include the original consoles of the Mercury Mission Control room with the world map that was used to follow the path of the John Glenn capsule Friendship 7 between tracking stations in 1962. Credit: Ken Kremer/kenkremer.com
Further details about ‘Heroes and Legends, the U.S. Astronaut Hall of Fame and all other attractions are available at the Kennedy Space Center Visitor Complex website: https://www.kennedyspacecenter.com/
Stay tuned here for Ken’s continuing Earth and Planetary science and human spaceflight news.
Learn more about Heroes and Legends at KSCVC, GOES-R weather satellite, OSIRIS-REx, InSight Mars lander, SpaceX missions, Juno at Jupiter, SpaceX CRS-9 rocket launch, ISS, ULA Atlas and Delta rockets, Orbital ATK Cygnus, Boeing, Space Taxis, Mars rovers, Orion, SLS, Antares, NASA missions and more at Ken’s upcoming outreach events:
Nov 17-20: “GOES-R weather satellite launch, OSIRIS-REx launch, SpaceX missions/launches to ISS on CRS-9, Juno at Jupiter, ULA Delta 4 Heavy spy satellite, SLS, Orion, Commercial crew, Curiosity explores Mars, Pluto and more,” Kennedy Space Center Quality Inn, Titusville, FL, evenings
Moonrise over the London, as see from Waterloo Bridge on Nov. 13, 2016. Credit and copyright: Owen Llewellyn.
Now updated with more great images!
Although there’s been quite a bit of hype about the Super Moon on November 13, 2016, to many, the full Moon tonight may have appeared quite similar to other full Moon’s you’ve seen. Yes, the “super-ness” of this Moon, while noteworthy, is fairly imperceptible. While, as our own David Dickinson noted in his preview article, this full Moon is not only the closest for the year, but the nearest Full Moon for a 80 year plus span. However, the closest full moon of 2017 will be only 0.02% farther away than this one.
But any chance to get the public to look up at the night sky is a good one! And we’ll also take this opportunity to share some of the great images from around the world posted on Universe Today’s Flickr page, as well as on social media. Enjoy!
Here’s a “classic” but gorgeous look at the Moon:
The Moon just before full on November 13, 2016 imaged through cloud from London. Credit and copyright: Roger Hutchinson.Supermoon over Glastonbury Tor, Somerset, England on Nov. 13, 2016. Credit and copyright: Tim Graham/TJG Photography.Some astrophotographers took this opportunity to take close-ups of the Moon’s surface. Pythagoras and Babbage Craters are seen here in this image from the UK on Nov. 13, 2016. Credit and copyright: Alun Halsey.The ‘Super Moon’ over Rome on November 14, 2016. Credit and copyright: Gianluca Masi.A view of the supermoon as seen from Lahore, Pakistan, with color added for contrast. Credit and copyright: Roshaan Bukhari.Moon and clouds as seen from the UK on Nov. 13, 2016. Credit and copyright: Sculptor Lil on Flickr.Pale Moon rising, as seen from North Bedfordshire, UK on Nov. 13, 2016. Credit and copyright: Dawn Sunrise on Flickr.
Super-Kamiokande, a neutrino detector in Japan, holds 50,000 tons of ultrapure water surrounded by light tubes. Credit: Super-Kamiokande Observatory
Under Mount Ikeno, Japan, in an old mine that sits one-thousand meters (3,300 feet) beneath the surface, lies the Super-Kamiokande Observatory (SKO). Since 1996, when it began conducting observations, researchers have been using this facility’s Cherenkov detector to look for signs of proton decay and neutrinos in our galaxy. This is no easy task, since neutrinos are very difficult to detect.
But thanks to a new computer system that will be able to monitor neutrinos in real-time, the researchers at the SKO will be able to research these mysteries particles more closely in the near future. In so doing, they hope to understand how stars form and eventually collapse into black holes, and sneak a peak at how matter was created in the early Universe.
Neutrinos, put simply, are one of the fundamental particles that make up the Universe. Compared to other fundamental particles, they have very little mass, no charge, and only interact with other types of particles via the weak nuclear force and gravity. They are created in a number of ways, most notably through radioactive decay, the nuclear reactions that power a star, and in supernovae.
Timeline of the Big Bang, which unleashed cosmic neutrinos that can still be detected today. Credit: NASA / JPL-Caltech / A. Kashlinsky (GSFC).
In accordance with the standard Big Bang model, the neutrinos left over from the creation of the Universe are the most abundant particles in existence. At any given moment, trillions of these particles are believed to be moving around us and through us. But because of the way they interact with matter (i.e. only weakly) they are extremely difficult to detect.
For this reason, neutrino observatories are built deep underground to avoid interference from cosmic rays. They also rely on Cherenkov detectors, which are essentially massive water tanks that have thousands of sensors lining their walls. These attempt to detect particles as they are slowed down to the local speed of light (i.e. the speed of light in water), which is made evident by the presence of a glow – known as Cherenkov radiation.
The detector at the SKO is currently the largest in the world. It consists of a cylindrical stainless steel tank that is 41.4 m (136 ft) tall and 39.3 m (129 ft) in diameter, and holds over 45,000 metric tons (50,000 US tons) of ultra-pure water. In the interior, 11,146 photomultiplier tubes are mounted, which detect light in the ultraviolet, visible, and near-infrared ranges of the electromagnetic spectrum with extreme sensitivity.
For years, researchers at the SKO have used the facility to examine solar neutrinos, atmospheric neutrinos and man-made neutrinos. However, those that are created by supernovas are very difficult to detect, since they appear suddenly and difficult to distinguish from other kinds. However, with the newly-added computer system, the Super Komiokande researchers are hoping that will change.
Cherenkov radiation glowing in the core of the Advanced Test Reactor at the Idaho National Laboratory Credit: Wikipedia Commons/Argonne National Laboratory
“Supernova explosions are one of the most energetic phenomena in the universe and most of this energy is released in the form of neutrinos. This is why detecting and analyzing neutrinos emitted in these cases, other than those from the Sun or other sources, is very important for understanding the mechanisms in the formation of neutron stars –a type of stellar remnant– and black holes”.
Basically, the new computer system is designed to analyze the events recorded in the depths of the observatory in real-time. If it detects an abnormally large flows of neutrinos, it will quickly alert the experts manning the controls. They will then be able to assess the significance of the signal within minutes and see if it is actually coming from a nearby supernova.
“During supernova explosions an enormous number of neutrinos is generated in an extremely small space of time – a few seconds – and this why we need to be ready,” Labarga added. “This allows us to research the fundamental properties of these fascinating particles, such as their interactions, their hierarchy and the absolute value of their mass, their half-life, and surely other properties that we still cannot even imagine.”
The Super-Kamiokande experiment is located at the Kamioka Observatory, 1,000 m below ground in a mine near the Japanese city of Kamioka. Credit: Kamioka Observatory/ICRR/University of Toky
Equally as important is the fact this system will give the SKO the ability to issue early warnings to research centers around the world. Ground-based observatories, where astronomers are keen to watch the creation of cosmic neutrinos by supernova, will then be able to point all of their optical instruments towards the source in advance (since the electromagnetic signal will take longer to arrive).
Through this collaborative effort, astrophysicists may be able to better understand some of the most elusive neutrinos of all. Discerning how these fundamental particles interact with others could bring us one step closer to a Grand Unified Theory – one of the major goals of the Super-Kamiokande Observatory.
To date, only a few neutrino detectors exist in the world. These include the Irvine-Michigan-Brookhaven (IMB) detector in Ohio, the Subdury Neutrino Observatory (SNOLAB) in Ontario, Canada, and the Super Kamiokande Observatory in Japan.
The Subaru Telescope atop Mauna Kea. CHARIS works in conjunction with Subaru. Image: Dr. Hideaki Fujiwara - Subaru Telescope, NAOJ.
The revelation that there are thousands of planets out there, orbiting other stars, is mostly due to the success of the Kepler mission. But now that we know these exoplanets are there, we want to know all about them. We want to know their mass, their temperature, how old they are, and pretty much everything else about them.
Now, a new instrument called the Coronagraphic High Angular Resolution Imaging Spectrograph (CHARIS) has captured the light from one of those exoplanets. This has the researchers excited about what they can see.
“We couldn’t have been more pleased by the results.” – N. Jeremy Kasdin
CHARIS allows astronomers to isolate light reflecting from planets. That’s difficult to do, since they are so much dimmer than the stars they orbit. CHARIS is able to isolate the reflective light from planets larger than Jupiter. Then astronomers can analyze that light to learn about the planet’s age, atmospheric composition, and its size.
“By analyzing the spectrum of a planet, we can really understand a lot about the planet. You can see specific features that can allow you to understand the mass, the temperature, the age of the planet.” – team member Tyler Groff
This image from the CHARIS instrument shows planets located around a star in the planetary system HR8799. Image: N. Jeremy Kasdin and team.
CHARIS was designed and built by a team led by N. Jeremy Kasdin, a professor of mechanical and aerospace engineering at Princeton University. It took them five years to build CHARIS.
The spectrograph sits inside a 500 lb case that measures 30x30x12. Inside that case, it’s kept at -223.15 Celsius (50 Kelvin, -369 F.) The CHARIS instrument has nine mirrors, five filters, two prism assemblies and a microlens array. The microlens array is a special optical device with an array of tiny lenses etched into its surface.
During a CHARIS field test, researchers captured images of celestial objects, including vapor clouds moving across a section of the planet Neptune. (Images courtesy of N. Jeremy Kasdin and the research team)
CHARIS works in conjunction with the Subaru Telescope in Hawaii. It’s part of a long-time collaboration between Princeton, the University of Tokyo and the National Astronomical Observatory of Japan, which operates the Subaru Telescope at Mauna Kea, Hawaii. And these first results are generating a lot of interest.
According to Tyler Groff, a team member from Princeton who now works for NASA, the preliminary result from CHARIS have generated a lot of interest from the astronomy community. The CHARIS team is now reviewing research proposals.
“There is a lot of excitement,” Groff said. “Charis is going to open for science in February to everyone.”
CHARIS is designed to capture the light from distant exoplanets, so its field of view is tiny. It’s only 2 arc-seconds, which is a tiny patch of sky. For reference, the full Moon is about 1,800 arc-seconds. But it can take images across a wide band of light wavelengths. The fact that it captures such a wide band of light is what allows such detailed analysis of anything it’s pointed at.
“We tested CHARIS on Neptune, but the entire planet doesn’t even fit on our detector.” -Tyler Groff
CHARIS is located behind a coronagraph. The coronagraph channels light from the Subaru Telescope and divides the light coming directly from a star from the light that is reflecting off planets orbiting that star. The team says it’s like picking out the light reflecting from a speck of tinsel floating in front of a spotlight that’s hundreds of miles away.
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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 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 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:
Artists impression of a Super-Earth, a class of planet that has many times the mass of Earth, but less than a Uranus or Neptune-sized planet. Credit: NASA/Ames/JPL-Caltech
Red dwarf stars have proven to be a treasure trove for exoplanet hunters in recent years. In addition to multiple exoplanets candidates being detected around stars like TRAPPIST-1, Gliese 581, Gliese 667C, and Kepler 296, there was also the ESO’s recent discovery of a planet orbiting within the habitable zone of our Sun’s closest neighbor – Proxima Centauri.
And it seems the trend is likely to continue, with the latest discovery comes from a team of European scientists. Using data from the ESO’s High Accuracy Radial velocity Planet Searcher (HARPS) and HARPS-N instruments, they detected an exoplanet candidate orbiting around GJ 536 – an M-class red dwarf star located about 32.7 light years (10.03 parsecs) from Earth.
According to their study, “A super-Earth Orbiting the Nearby M-dwarf GJ 536“, this planet is a super-Earth – a class of exoplanet that has between more than one, but less than 15, times the mass of Earth. In this case, the planet boasts a minimum of 5.36 ± 0.69 Earth masses, has an orbital period of 8.7076 ± 0.0025 days, and orbits its sun at a distance of 0.06661 AU.
Artist’s impression of a system of exoplanets orbiting a low mass, red dwarf star. Credit: NASA/JPL
The team was led by Dr. Alejandro Suárez Mascareño of the Instituto de Astrofísica de Canarias (IAC). The discovery of the planet was part of his thesis work, which was conducted under Dr Rafael Rebolo – who is also a member of the IAC, the Spanish National Research Council and a professor at the University of Laguna. And while the planet is not a potentially habitable world, it does present some interesting opportunities for exoplanet research.
As Dr. Mascareño shared with Universe Today via email:
“GJ 536 b is a small super Earth discovered in a very nearby star. It is part of the group of the smallest planets with measured mass. It is not in the habitable zone of its star, but its relatively close orbit and the brightness of its star makes it a promising target for transmission spectroscopy IF we can detect the transit. With a star so bright (V 9.7) it would be possible to obtain good quality spectra during the hypothetical transit to try to detect elements in the atmosphere of the planet. We are already designing a campaign for next year, but I guess we won’t be the only ones.”
The survey that found this planet was part of a joint effort between the IAC (Spain) and the Geneva Observatory (Switzerland). The data came from the HARPS and HARPS-N instruments, which are mounted on the ESO’s 3.6 meter telescope at the La Silla Observstory in Chile and the 3.6 meter telescope at the La Palma Observatory in Spain. This was combined with photometric data from the All Sky Automated Survey (ASAS), which has observatories in Chile and Maui.
The research team relied on radial velocity measurements from the star to discern the presence of the planet, as well as spectroscopic observations of the star that were taken over a 8.6 year period. For all this, they not only detected an exoplanet candidate with 5 times the mass of Earth, but also derived information on the star itself – which showed that it has a rotational period of about 44 days, and magnetic cycle that lasts less than three years.
Artist’s depiction of the interior of a low-mass star, such as the one seen in an X-ray image from Chandra in the inset. Credit: NASA/CXC/M.Weiss
By comparison, our Sun has a rotational period of 25 days and a magnetic cycle of 11 years, which is characterized by changes in the levels of solar radiation it emits, the ejection of solar material and in the appearance of sunspots. In addition, a recent study from the the Harvard Smithsonian Center for Astrophysics (CfA) showed that Proxima Centauri has a stellar magnetic cycle that lasts for 7 years.
This detection is just the latest in a long line of exoplanets being discovered around low-mass, low-luminosity, M-class (red dwarf) stars. And looking ahead, the team hopes to continue surveying GJ 536 to see if there is a planetary system, which could include some Earth-like planets, and maybe even a few gas giants.
“For now we have detected only one planet, but we plan to continue monitoring the star to search for other companions at larger orbital separations,” said Dr. Mascareño. “We estimate there is still room for other low-mass or even Neptune-mass planets at orbits from a hundred of days to a few years.”
The research also included scientists from the Astronomical Observatory at the University of Geneva, the University of Grenoble, The Astrophysical and Planetological Insitute of Grenoble, Institute of Astrophysics and Space Sciences in Portugal, and the University of Porto, Portugal.
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Artist's concept of Trojan asteroids, small bodies that dominate our solar system. Credit: NASA
If we are indeed stardust, then what will our future hold? And what happened to all that other dust that isn’t in people or planets? These are pretty heady questions perhaps best left for late at night. Since the age of Galileo and perhaps even beforehand these inquisitive night goers have sought an understanding of “What’s out there?” Paul Murdin in his book “Rock Legends – the Asteroids and Their Discoverers” doesn’t answer the big questions directly but he does shed some capricious light upon what the night time reveals and what the future may hold.
We’re pretty confident that our solar system evolved from a concentration of dust. Let’s leave aside the question about where the dust came from and assume that, at a certain time and place, there was enough free dust that our Sun was made and so too all the planets. In a nice, orderly universe all the dust would have settled out. However, as we’ve discovered since at least the time of Galileo this didn’t happen. There are a plethora of space rocks — asteroids — out wandering through our solar system.
And this is where Murdin’s book steps up. Once people realized that there more than just a few asteroids out there, they took to identifying and classifying them. The book takes a loosely chronological look at this classification and at our increasing knowledge of the orbits, sizes, densities and composition of these space wanderers.
Fortunately this book doesn’t just simply list discovery dates and characteristics. Rather, it includes significant amounts of its contents on the juicy human story that tags along, especially with the naming. It shows that originally these objects were considered special and refined and thus deserved naming with as much aplomb as the planets; i.e. using Greek and Roman deities. Then the number of discovered asteroids outpaced the knowledge of ancient lore, so astronomers began using the names of royalty, friends and eventually pets. Today with well over a million asteroids identified setting a name to an asteroid doesn’t quite have the same lustre, as the author is quick to point out with his own asteroid (128562) Murdin. Yet perhaps there’s not much else to do while waiting for a computer program to identify a few hundred more accumulations of dust, so naming some of the million nameless asteroids could happily fill in some time.
With the identifying of the early asteroid discoverers and the fun names they chose, this part of the book is quite light and simple. It expands the fun by wandering a bit just like the asteroids. From it you learn of the discovery of palladium, the real spelling of Spock’s name and the meaning of YORP. Sometimes the wandering is quite far, as with the origins of the Palladium Theatre, the squabbling surrounding the naming of Ceres and the status of the Cubewanos. Yet it is this capriciousness that gives the book its flavour and makes it great for a budding astronomer or a reference for a generalist. The occasional bouts of reflection on the future of various asteroids and even of the Earth add a little seriousness to an otherwise pleasant prose.
So if you’re wondering about the next occultation of Eris or the real background of the name (3512) Eriepa then you’re into asteroids. And perhaps you’re learning how to survive on a few hours of sleep so you can search for one more faint orbiting mote. Whether that’s the case or you’re just interested in how such odd names came to represent these orbiting rocks then Paul Murdin’s book “Rock Legends – the Asteroids and Their Discoverers” will be a treat. Read it and maybe you can use it to place your own curve upon an asteroid’s name.
