Ion Propulsion: The Key to Deep Space Exploration

The comforting blue glow of an ion drive. Image Credit: NASA
The comforting blue glow of an ion drive. Image Credit: NASA

When we think of space travel, we tend to picture a massive rocket blasting off from Earth, with huge blast streams of fire and smoke coming out the bottom, as the enormous machine struggles to escape Earth’s gravity. Rockets are our only option for escaping Earth’s gravity well—for now. But once a spacecraft has broken its gravitational bond with Earth, we have other options for powering them. Ion propulsion, long dreamed of in science fiction, is now used to send probes and spacecraft on long journeys through space.

NASA first began researching ion propulsion in the 1950’s. In 1998, ion propulsion was successfully used as the main propulsion system on a spacecraft, powering the Deep Space 1 (DS1) on its mission to the asteroid 9969 Braille and Comet Borrelly. DS1 was designed not only to visit an asteroid and a comet, but to test twelve advanced, high-risk technologies, chief among them the ion propulsion system itself.

Ion propulsion systems generate a tiny amount of thrust. Hold nine quarters in your hand, feel Earth’s gravity pull on them, and you have an idea how little thrust they generate. They can’t be used for launching spacecraft from bodies with strong gravity. Their strength lies in continuing to generate thrust over time. This means that they can achieve very high top speeds. Ion thrusters can propel spacecraft to speeds over 320,000 kp/h (200,000 mph), but they must be in operation for a long time to achieve that speed.

An ion is an atom or a molecule that has either lost or gained an electron, and therefore has an electrical charge. So ionization is the process of giving a charge to an atom or a molecule, by adding or removing electrons. Once charged, an ion will want to move in relation to a magnetic field. That’s at the heart of ion drives. But certain atoms are better suited for this. NASA’s ion drives typically use xenon, an inert gas, because there’s no risk of explosion.

Detail of an ion drive. Image: NASA Glenn Research Center. Vectorization by Chabacano
Detail of an ion drive. Image: NASA Glenn Research Center. Vectorization by Chabacano

In an ion drive, the xenon isn’t a fuel. It isn’t combusted, and it has no inherent properties that make it useful as a fuel. The energy source for an ion drive has to come from somewhere else. This source can be electricity from solar cells, or electricity generated from decay heat from a nuclear material.

Ions are created by bombarding the xenon gas with high energy electrons. Once charged, these ions are drawn through a pair of electrostatic grids—called lenses—by their charges, and are expelled out of the chamber, producing thrust. This discharge is called the ion beam, and it is again injected with electrons, to neutralize its charge. Here’s a short video showing how ion drives work:

 

Unlike a traditional chemical rocket, where its thrust is limited by how much fuel it can carry and burn, the thrust generated by an ion drive is only limited by the strength of its electrical source. The amount of propellant a craft can carry, in this case xenon, is a secondary concern. NASA’s Dawn spacecraft used only 10 ounces of xenon propellant—that’s less than a soda can—for 27 hours of operation.

NASA Evolutionary Xenon Thruster. Image Credit: NASA
NASA Evolutionary Xenon Thruster. Image Credit: NASA

In theory, there is no limit to the strength of the electrical source powering the drive, and work is being done to develop even more powerful ion thrusters than we currently have. In 2012, NASA’s Evolutionary Xenon Thruster (NEXT) operated at 7000w for over 43,000 hours, in comparison to the ion drive on DS1 that used only 2100w. NEXT, and designs that will surpass it in the future, will allow spacecraft to go on extended missions to multiple asteroids, comets, the outer planets, and their moons.

Missions using ion propulsion include NASA’s Dawn mission, the Japanese Hayabusa mission to asteroid 25143 Itokawa, and the upcoming ESA missions Bepicolombo, which will head to Mercury in 2017, and LISA Pathfinder, which will study low frequency gravitational waves.

With the constant improvement in ion propulsion systems, this list will only grow.

Bio-Mimicry and Space Exploration

A close-up of the spiral pattern in a sunflower. (Image Credit: Vishwas Krishna, unaltered, CC2.0)
Sunflowers doing what they do best: capturing sunlight. (Image Credit: OiMax, image unaltered, CC2.0)

“Those who are inspired by a model other than Nature, a mistress above all masters, are laboring in vain.

-Leonardo DaVinci

What DaVinci was talking about, though it wasn’t called it at the time, was biomimicry. Biomimicry is the practice of using designs from the natural world to solve technological and engineering problems. Were he alive today, there’s no doubt that Mr. DaVinci would be a big proponent of biomimicry.

Nature is more fascinating the deeper you look into it. When we look deeply into nature, we’re peering into a laboratory that is over 3 billion years old, where solutions to problems have been implemented, tested, and revised over the course of evolution. That’s why biomimicry is so elegant: on Earth, nature has had more than 3 billion years to solve problems, the same kinds of problems we need to solve to advance in space exploration.

The more powerful our technology gets, the deeper we can see into nature. As greater detail is revealed, more tantalizing solutions to engineering problems present themselves. Scientists who look to nature for solutions to engineering and design problems are reaping the rewards, and are making headway in several areas related to space exploration.

Continue reading “Bio-Mimicry and Space Exploration”

NASAs Ten-Engine Electric Plane

NASA has been grabbing headlines recently with their potentially game-changing emDrive propulsion system. The emDrive has generated a lot of discussion, and a lot of controversy too. But NASA has a lot more going on than futuristic space travel designs, and one recent test flight showed that the minds at NASA are still working on innovative designs for flight systems that operate in Earth’s atmosphere.

The Greased Lightning 10, or GL10, is a remotely piloted, ten engine aircraft that can take off and land vertically, and then rotate its wings for forward flight. This type of system has been developed before in full size, piloted aircraft like the V22 Osprey, but it’s never been done before in a small, remotely-piloted aircraft.
Continue reading “NASAs Ten-Engine Electric Plane”

Book Review: How To Build a Universe

We live in a wild and crazy universe. Gigantic stars explode and create the stuff of life, virtual particles pop in and out of existence so fast they can barely be measured, and light exists as particles and waves at the same time. And it all started with three simple words: The Big Bang. It’s taken hundreds of years of science to begin to sort some of this out, so for one author to write one book that tells the whole story is an enormous task.

Enter Ben Gilliland, science columnist, gifted illustrator, and winner of the 2013 Sir Arthur Clarke Award for Space Achievement in Media. Gilliland tackles the task in his new book “How to Build a Universe: from The Big Bang to the End of the Universe.” He uses engaging storytelling, eye-catching graphics, and a relaxed and friendly style of writing that makes reading his book an enjoyable and informative experience.

“How To Build A Universe” reads like a conversation with a knowledgeable and enthusiastic friend. Gilliland leads us through the twists and turns of the story of the universe and uses his skill as an illustrator to great narrative effect. From The Big Bang, to the discovery of the atom. From the point in time when other galaxies will become invisible to observers on Earth, to the eventual death of the universe, it’s all explained with wit and detail.

If you’ve ever picked up a book about space science, opened the first page and then asked yourself why you didn’t take cosmology and astrophysics in university, this book is for you. There’s none of that with Gilliland’s book. This book grabs the reader right away, and is engaging from start to finish.

You would have to take several university level courses in astronomy, astrophysics, and cosmology to cover as much ground as “How To Build A Universe” does in 224 pages. And your professors probably wouldn’t be near as engaging as the author, Ben Gilliland. (You’d go to more parties if you went to university, but that’s another subject.)

Don’t get the wrong idea. This book is not dumbed down. It finds its audience nicely. It touches on all the important topics, and digs into the detail with clarity and humour. The writing is clear and concise at the same time that it’s warm and informal. Beyond the writing, it’s the wealth of thoughtful illustrations that help pull it all together.

I’m a technical writer, and I know how hard it can be to explain complicated subjects to people. Ben Gilliland makes it seem effortless. His explanations of quantum physics are particularly effective, and they’re the clearest explanation of that challenging material that I’ve ever come across. I could say the same thing about how he handles Dark Matter and Dark Energy, two other difficult to explain concepts.

Gilliland is a gifted writer and illustrator, and I highly recommend “How To Build a Universe” to Universe Today readers.

Book Review and Giveaway: The Constellation Observing Atlas

Here is another giveaway just in time for the holidays: The Constellation Observing Atlas by Grant Privett and Kevin Jones. Springer and Universe Today are giving away free copies to two lucky Universe Today readers.

Review by: Evan Gough

The night sky is vast and full of wonders, and binoculars or a telescope can bring these wonders into view. The planets and the moon are easy to find, but after that, the rest of the objects in the night sky can be challenging to locate. “The Constellation Observing Atlas,” by Grant Privett and Kevin Jones, will guide you around the night sky, and help you find the most interesting objects.

This atlas uses the patterns of the constellations to cut the sky up into bite-sized pieces, giving the amateur observer an easy to use method for exploring the night sky. “The Constellation Observing Atlas” has a section for each one of the eighty-eight constellations recognized by the International Astronomical Union, from Andromeda to Vulpecula.

General information about each constellation is included, followed by the history of its name and mapping, any notable double and variable stars are mentioned and any deep sky objects that reside in or near the constellation are listed. Along with some nice images, “The Constellation Observing Atlas” also has detailed maps of each constellation which helps make the observing process straightforward.

The book is well laid out, and the amount of information for each constellation is just right. The maps are detailed and helpful and I found the history sections very interesting and amusing. The authors don’t mind having a little fun at the ancient’s expense for some of their comical constellation choices and the convoluted myths behind them, and who can blame them? Many of the constellations are just vague clumps and arrangements of stars in which the ancients somehow saw their most powerful gods, mythical creatures, and heroes.

Like many Universe Today readers, I’m interested in all things astronomy and space, but I’m far from an expert observer. “The Constellation Observing Atlas” tries to make the night sky accessible for amateurs like myself, and it works. You simply locate a constellation in the sky, check the book for interesting viewing targets, point your ‘scope around, and have some fun. Some of the stars and deep sky objects will be challenging to find, and the authors give detailed information for finding these elusive targets.

In my part of the world, winter has come and I’m in store for some clear, cold, crisp nights. There should be some great observing conditions ahead, with Orion prominent in the night sky. I’m looking forward to using “The Constellation Observing Atlas” to expand my observing. The authors have done a good job of being informative and fun, and I highly recommend this book to amateur and novice observers. It makes the wonders of the night sky accessible, one constellation at a time.

In order to be entered into the giveaway drawing, just put your email address into the box at the bottom of this post (where it says “Enter the Giveaway”) before Monday, December 16th, 2013. We’ll send you a confirmation email, so you’ll need to click that to be entered into the drawing.

Don’t want to wait to see if you won? Get your copy in time for Christmas from Amazon.com

Giveaway: The Shirtsleeve Invention by Gloria Beasley Lauston

I love all things space related. I’m excited by the jaw-dropping images from the Hubble, awed by the Kepler spacecraft’s discoveries, and to be honest, almost moved to tears by the successful landing of the Mars Science Laboratory. As a boy, the Space Shuttle program seemed like science fiction come to life. Behind these peak moments in discovery, there are a lot of people doing a lot of hard work, dedicating their whole lives to solving one problem. One such person is Robert Beasley, the man behind the Thermal Protection tiles used on the Space Shuttle. Robert Beasley was an American chemist who invented and developed the Thermal Protection system for the Space Shuttles which allowed them to re-enter Earth’s atmosphere without burning up.

Universe Today and Bohlsen Group are teaming up to give away 2 free copies of The Shirtsleeve Invention by Gloria Beasley Lausten. Here’s how:

In order to be entered into the giveaway drawing, just put your email address into the box at the bottom of this post (where it says “Enter the Giveaway”) before Friday, September 13, 2013. We’ll send you a confirmation email, so you’ll need to click that to be entered into the drawing.

 

The Shirtsleeve Invention is the story of Beasley and his idea. The book is a very detailed history of Beasley’s life and career; sometimes a little too detailed. The Shirtsleeve Invention is written by his widow, Gloria Beasley Lausten, who is not a professional writer. At times it is a deeply personal account of her husband. It contains the kind of detail that only a spouse would know, so along with being an account of Beasley’s career, and how his drive and determination helped lead to the development of the Space Shuttle, it also contains lots of detail about his personal life and struggles through childhood, college, and adult life. The book is so personal and full of insight, it’s quite touching at times.

Interviewed after the initial successful flight and re-entry of the Space Shuttle Columbia in 1981, when Beasley’s ceramic tile system did its job and protected Columbia from the 2400 degree heat of re-entry, Bob said to a reporter, “That’s the end of so many years of heartache you can’t imagine. All the heartaches, all the stress, it was worth it.”

The meat of The Shirtsleeve Invention is the account of his idea for the Space Shuttles, and how the idea grew. How he struggled to convince others that his idea was a sound one. It wasn’t always easy, but like things sometimes turn out, his idea proved to be the key for the development of the Space Shuttle and the things that followed. Without the Shuttle Program, there would be no International Space Station and no Hubble Space Telescope. Without Beasley and his creativity and perseverance, who knows where the state of space exploration would be?

This book is a little miscast as a science book. There’s science in there, but for me the book bogged down a little with too much detail about his personal life. There are lots of letters back and forth between him and his relatives and future wife detailing his struggles in school and early working life. The book is realistic; no doubt about that. Without Robert Beasley, and countless others like him, where would the state of human knowledge be? He’s certainly deserving of recognition.

I enjoyed the book, but I found myself skimming over some of the more detailed parts of his private life. Universe Today readers may have a similar experience reading it. But for those of you specifically interested in the lives of people behind the science of space exploration, The Shirtsleeve Invention is for you.

If you don’t want to wait for the win, you can buy a copy on Amazon.com

Book Review: The Life and Death of Stars

“The Life and Death of Stars” is a thorough and richly detailed book that will tell you all you want to know about stars. The author, Kenneth R. Lang, is Professor of Astronomy at Tufts University, and he clearly has the knowledge and explanatory ability of someone who has spent his life studying stars. Though its density may deter the casual reader, I found this book engrossing from beginning to end.

If you’ve just been recently bitten by the astronomy bug, this book may not be for you. A more introductory book might be a better choice. But if you’re craving a deeper and more comprehensive understanding of stars, this book will deliver. Make no mistake though; for most readers, it will require some commitment to read your way through this book.

I was never an astrophysics student, but this book seems to me to have a textbook like thoroughness, though not in a dry way. The chapters and topics flow along logically and clearly, with the help of numerous charts and illustrations. For instance, the book starts off with a thorough explanation of light. Since almost all that we know about stars we’ve learned by observing light, where else should a book on astrophysics begin?

From there, the book moves on to chapters titled “Transmutation of the Elements,” “New Stars Arise from the Darkness,” and “Stellar End States,” with other stops in between. The final chapter is titled “Birth, Life, and Death of the Universe.” At the very end of the book, Lang discusses the possible endings of the Universe, and how the mystery of Dark Matter and Dark Energy may dictate the end.

My own understanding of the behaviour and lifecycle of stars has grown enormously from reading this book, and yours will too. For example, if you know that stars form when interstellar gas clouds collapse from their own gravity, but don’t understand exactly how, then “The Life and Death of Stars” will tell you all the detail you’ll need to know. If you know that heavier elements are formed via nucleosynthesis, in the hearts of stars, but you don’t grasp the finer details of that process, then the explanation in this book will bring it to life for you.

Lang is not a populariser of astronomy. His strength is in detailed descriptions, delivered in a comprehensible way. However, he’s not opposed to the occasional poetic turn of phrase: “All stars are impermanent beacons that eventually will cease to shine, vanishing like a circle of fire turning to ash.” True that. He also quotes the Bhagavad Gita, and the poet Shelley.

One of the ways I gauge a book is by my own level of excitement and interest as I’m reading it. I also judge a book by its clarity of explanation and its flow. In both these respects, Lang delivers with this book. After reading it, I’ll definitely be checking out his other books.

“The Life and Death of Stars” broadened and deepened my understanding of all things stellar. It’s a fantastic book, and I wholeheartedly recommend it to Universe Today readers who wish to expand their knowledge of astrophysics.

Book Review: Unraveling the Universe’s Mysteries

“Unraveling the Universe’s Mysteries” is Louis A. Del Monte’s contribution to the world of science writing. If you haven’t heard of him, don’t be surprised. He’s not a prolific author or researcher, but worked in the development of microelectronics for the US companies IBM and Honeywell before forming a high-tech e-marketing agency.

The book lives up to its title and long subtitle: “Explore sciences’ most baffling mysteries, including the Big Bang’s origin, time travel, dark energy, humankind’s fate, and more.” It covers string theory, the Big Bang, dark matter, dark energy, time travel, the existence of God, and other mysterious aspects of our Universe. Del Monte also discusses artificial intelligence, the end of the Universe, and the mysterious nature of light. These subjects have all been covered in great detail by other authors in other books. How does Del Monte’s treatment of these subjects stand up in comparison?


Not great, in my opinion. The writing is somehow uninviting. The book reads more like a textbook or a lecture than it does a science book for an interested audience. It’s somewhat dry, and the writing is kind of heavy. After looking into Del Monte’s background, it becomes clear why. He’s an engineer, and his background is in writing technical papers.

This book is a bit of a puzzle, as is the author himself. I’ve mentioned the problems with the writing, but there are other issues. In one instance Del Monte references a study from the Journal of Cosmology. If you haven’t heard of that journal, it’s come under heavy criticism for its peer-review process, and isn’t highly regarded in science circles. The Journal of Cosmology seems to be a journal for people with an axe to grind around certain issues more than a healthy part of the science journal community. To be quoting studies from it is a bit of a black mark, in my opinion.

In another instance, he opens the chapter on Advanced Aliens with a quote from “Chariot of the Gods”, that old book/documentary from the 1970’s that just won’t seem to die, no matter how discredited it is. The main thrust of “Chariot of the Gods” is that human civilisation got a technological boost from visitations by advanced aliens. Readers can judge for themselves the wisdom of quoting “Chariot of the Gods” in a science book.

The publisher bills the book as “a new theory to explain one of cosmology’s most profound mysteries, the accelerated expansion of the universe,” and that Del Monte “presents an original solution to Einstein’s equations of special relativity.” But without conducting peer reviewed research, the validity of his theory comes into question.

If I seem puzzled by this book, it’s because I am. Del Monte seems to be a bit of an outsider when it comes to writing about astronomy and cosmology. He has no background in it. There’s nothing wrong with that in principle; there’s always room for new perspectives in science. But I can’t help thinking that he could’ve benefited from working more closely with an experienced editor.

Readers will get something out of this book; it’s an interesting discussion of the mysterious aspects of our Universe. But it’s also a somewhat strange book. For those of you who decide to read it, you’re in for an interesting read.

For more information about Louis Del Monte, see his website.

Book Review: “Hubble’s Universe: Greatest Discoveries and Latest Images”

The Hubble Space Telescope has been the subject of several books and articles, and certainly much more will be written about it in the future, as its status as the world’s most successful science experiment will guarantee that. And though breathtaking images are what hooks many people on the telescope, the Hubble was designed and built to do more than just take pretty pictures. The Hubble was planned and built to shed light on several different issues in astronomy and cosmology.

A new book, “Hubble’s Universe: Greatest Discoveries and Latest Images,” by Terence Dickinson, explains the important contributions Hubble has made in the areas of galactic evolution, dark matter and dark energy, and the expansion rate of the Universe. After a quick recounting of the Hubble’s launch and its well-documented initial problems, the author spells out Hubble’s top discoveries, including Hubble’s contribution to our understanding of the super-massive black holes at the centre of galaxies and our first looks at the atmospheres of extra-solar planets.

But the book is more than just clear and readable explanations of discoveries in astronomy. It’s a stunning picture book, equally at home in the living room as it is in the study. The array of pictures is simply awesome, and as Universe Today readers know, astronomy photos can suck anyone in.

See a gallery of new images from the book here.

Find out how you can win a copy of this book here.
The Hubble Space Telescope and the people that work with it are responsible for the images in this book, but it takes a special person to put a book like this together. The author, Terence Dickinson, is well-known in astronomy circles. If you don’t know who he is, you should. He’s the author of the top-selling star-gazing guide in the world, “NightWatch: A Practical Guide to Viewing the Universe,” as well as 14 other books. He’s won numerous awards for science-writing and for the popularization of science. An accomplished astro-photographer, one of his photos of the Moon has been on a U.S. postage stamp. He’s even been awarded the Order of Canada, the country’s second highest honour for merit. Terence Dickinson has a healthy passion for science, and has spent his life igniting that passion in others.

“Hubble’s Universe” is loaded with hundreds of photos of the kind we’ve become used to from Hubble, and some in the book have never before been published (see some of them here). The beauty of glowing gas clouds, the rich luminescence of filaments of gas and dust in distant nebulae, the beauty of the planets in our own solar system. This book is basically a feast of astrophotography.

While many books have been written about Hubble, this one will stack up against any of them. All Hubble books have stunning images in them, but what makes this one special is Dickinson’s ability for explanation. The writing is very accessible while still doing an outstanding job of handling some difficult subjects. If you’ve ever struggled with explanations of things like Dark Matter and Dark Energy, “Hubble’s Universe” will bring clarity, without any dumbing down of the subject matter.

You won’t regret buying this book, for yourself or perhaps for someone else. It’s destined to be a staple in libraries and astronomy collections. I’ll be bold and go a little further. “Hubble’s Universe” is destined to be a classic much like some of Dickinson’s other books.

Here’s a video of Dickinson discussing Hubble and his new book:

Could the Next Planetary Rover Come from Canada?

Prototype of the new Juno rover, a 300 kg rover for a mission to Mars or the Moon. Credit: CSA

The Canadian Space Agency is well known for its robotics but they’ve recently expanded from robotic arms to building prototypes for five new rovers, designed for future lunar and Mars missions. They range from microrovers to full-sized science missions and range in size from 30 kg up to 900 kg. The largest of them, the Lunar Exploration Light Rover, is designed to carry a scientific payload and can be fitted with a robotic arm. It has a range of 15 km, can be operated remotely, or can be used to carry astronauts across a planetary surface.

A version of the Juno rover with tires. Credit: CSA

The two Micro-Rover prototypes, at 40 kg and 30 kg., are designed to be operated in conjunction with larger rovers, and can be tethered to them and lowered into otherwise inaccessible areas.

“On the Moon, permanently shadowed craters provide many interesting areas to find water and other volatiles, Jean-Claude Piedboeuf, Director of Space Exploration Development at the Canadian Space Agency told Universe Today. “These craters have steep slopes making it difficult and risky for a large rover. Therefore, sending a micro-rover tethered to its mother one gives us the ability to explore the bottom of these craters with a minimum risk. Sending only a micro-rover could be an option. However, they are very slow so it is more efficient to have them on a larger rover to cover long distance and deploy them when needed.”

The micro-rovers can also be used to work alongside astronauts, to gain access to small spaces like caves.

The rovers should be mission-ready by about 2020, and NASA is already interested. Most missions to Mars and the Moon involve geology, and sometime in the future, mining. For instance, NASA has an experiment under consideration that entails digging up soil on the Moon and making hydrogen and oxygen out of it. These designs are intended to fit in with those types of activities.

Space robotics technology has long been a point of pride for Canadians, Canadarm was a fixture on the Space Shuttles and made it possible to do things like deploying satellites like the Hubble Space Telescope and was instrumental in building the International Space Station. CSA also built the huge Canadarm 2 and Dextre, the highly dexterous dual-armed robot, both of which reside on the International Space Station. More recently, CSA contributed a robotic arm and other equipment to Curiosity, the newest NASA rover to land on Mars.

Artemis is a light-weight terrestrial prototype that can either be operated by a human nearby or at a remote location, or use its onboard sensors to scan its environment and navigate without the need for a human operator. Credit: CSA

The new rover designs will add to the fine lineage of Canadian space robotics. Once they are deployed on missions to the Moon or Mars, they may end up elbowing the Canadarm and Dextre out of the spotlight. If they do take centre stage, no feelings will be hurt. Many of the same people who worked on the Canadarms and Dextre are involved in the development of the rovers.

“MDA (MacDonald, Detwiler and Associates) was the prime contractor for Canadarm and Dextre and is prime on three rover prototypes,” said Piedboeuf.

With these rover prototypes, CSA has avoided the one size fits all approach to rover design.

“The fleet developed by the Canadian industry for the CSA covers the range of applications we envisage and that will be welcomed by our international partners,” said Piedboeuf.

Though the CSA doesn’t anticipate any other rover designs, these 5 prototypes could be focused “on more specific applications such as in-situ resource utilization or science,” explained Piedboeuf.

If you find the unveiling of 5 new rover prototypes exciting, you’re in good company.

“People in industry, academia and within the CSA were excited to develop these rovers that could be one day on the Moon or Mars,” said Piedboeuf. “The opportunity of working on prototypes of space rovers with challenging requirements and advanced autonomy was a great motivation.”

See more images and information on the fleet of rovers at CSA’s website.