Self-Motivation
David Goggins
Former Navy Seal
Career Development
Bryan Cranston
Actor
Critical Thinking
Liv Boeree
International Poker Champion
Emotional Intelligence
Amaryllis Fox
Former CIA Clandestine Operative
Management
Chris Hadfield
Retired Canadian Astronaut & Author
Learn
from the world's big
thinkers
Start Learning

How futuristic ion rockets supercharge space exploration

What are the different types of rocket engines and will there be a rocket engine coming in the future that uses very little energy? NASA's Michelle Thaller explains.

Michelle Thaller: Hey Chris, it’s a really cool question about different types of rocket engines and whether there might be a rocket engine coming in the future that uses very little energy.

One of the big challenges of getting anything into space right now is you need to get it up out of the Earth’s gravity, and really the only way we had to do that is with fairly traditional rockets that use either solid rocket fuel or liquid rocket fuel, but it takes a huge amount of energy to get off the surface of the Earth.

Right now we don’t really have any better way to get things off the surface of the Earth, but things change once you get up into space.

And one of the things that I’m really excited about is something called an ion drive, and NASA uses these right now.

And an ion drive generates a tiny little bit of thrust, I mean it’s almost similar to just taking your hand and blowing on it, it’s about that much thrust. But you can turn an ion drive on and you can leave it on for years! So even though it’s a tiny little bit of thrust some of the fastest spacecraft that NASA now operates use ion drives.

One of my favorite missions is the Dawn Mission, which is actually surveying the larger asteroids in the asteroid belt. It went out to the asteroid Vesta and Vesta is about 300 miles across. It took wonderful pictures of Vesta and then it went onto the asteroid Ceres, which is actually the largest of the asteroids—it’s actually close to 700 miles across—and the images it returned of Ceres were absolutely amazing. And it was able to go from one asteroid to another because it had this ion drive that it could leave on for years.

And even though the thrust is tiny, keep that thrust going day after day, month after month, year after year you can get up to many, many tens of thousands of miles an hour.

So the way an ion drive works is—it basically can even use just electricity—It creates ions by actually ripping apart molecules into charged particles and then accelerating them out the back of the spacecraft. And really all you need is electricity. You can even run this on solar panels if you want.

So you can actually have an entire rocket engine up in space that is powered simply by solar energy and accelerating ions out the end of the spacecraft.

The problem is we don’t know how to use an ion engine to actually launch something into space. For that you need a lot of thrust, you need to actually get out of this strong gravity well of the Earth. So right now we sort of have these dual strategies for rocket engines, one that gets you up off the Earth (and those are pretty traditional), but then once you get into space turn on your ion drive, leave it on, get yourself going 30,000 miles an hour a little bit at a time, and you never need to turn it off.

What are the different types of rocket engines and will there be a rocket engine coming in the future that uses very little energy? NASA's Michelle Thaller explains and proposes that ion drives will transform everything. If only we could figure out how to get enough thrust.

The “new normal” paradox: What COVID-19 has revealed about higher education

Higher education faces challenges that are unlike any other industry. What path will ASU, and universities like ASU, take in a post-COVID world?

Photo: Luis Robayo/AFP via Getty Images
Sponsored by Charles Koch Foundation
  • Everywhere you turn, the idea that coronavirus has brought on a "new normal" is present and true. But for higher education, COVID-19 exposes a long list of pernicious old problems more than it presents new problems.
  • It was widely known, yet ignored, that digital instruction must be embraced. When combined with traditional, in-person teaching, it can enhance student learning outcomes at scale.
  • COVID-19 has forced institutions to understand that far too many higher education outcomes are determined by a student's family income, and in the context of COVID-19 this means that lower-income students, first-generation students and students of color will be disproportionately afflicted.
Keep reading Show less

How Hemingway felt about fatherhood

Parenting could be a distraction from what mattered most to him: his writing.

Ernest Hemingway Holding His Son 1927 (Wikimedia Commons)
Culture & Religion

Ernest Hemingway was affectionately called “Papa," but what kind of dad was he?

Keep reading Show less

The biology of aliens: How much do we know?

Hollywood has created an idea of aliens that doesn't match the science.

Videos
  • Ask someone what they think aliens look like and you'll probably get a description heavily informed by films and pop culture. The existence of life beyond our planet has yet to be confirmed, but there are clues as to the biology of extraterrestrials in science.
  • "Don't give them claws," says biologist E.O. Wilson. "Claws are for carnivores and you've got to be an omnivore to be an E.T. There just isn't enough energy available in the next trophic level down to maintain big populations and stable populations that can evolve civilization."
  • In this compilation, Wilson, theoretical physicist Michio Kaku, Bill Nye, and evolutionary biologist Jonathan B. Losos explain why aliens don't look like us and why Hollywood depictions are mostly inaccurate.
Keep reading Show less

Masturbation boosts your immune system, helping you fight off infection and illness

Can an orgasm a day really keep the doctor away?

Image by Yurchanka Siarhei on Shutterstock
Sex & Relationships
  • Achieving orgasm through masturbation provides a rush of feel-good hormones (such as dopamine, serotonin and oxytocin) and can re-balance our levels of cortisol (a stress-inducing hormone). This helps our immune system function at a higher level.
  • The surge in "feel-good" hormones also promotes a more relaxed and calm state of being, making it easier to achieve restful sleep, which is a critical part in maintaining a high-functioning immune system.
  • Just as bad habits can slow your immune system, positive habits (such as a healthy sleep schedule and active sex life) can help boost your immune system which can prevent you from becoming sick.
Keep reading Show less

Live on Tuesday | Personal finance in the COVID-19 era

Sallie Krawcheck and Bob Kulhan will be talking money, jobs, and how the pandemic will disproportionally affect women's finances.

Quantcast