![Hubble Space Telescope as seen during a servicing mission in 2009](/sites/default/files/styles/resource_card_image_360x300_/public/2020-02/hubble_space_telescope.jpg?itok=eNoDBFx5)
Airborne & Space Telescopes
Backgrounders
Learn about telescopes that do their work high in Earth’s atmosphere and in space.
![Boy looking through telescope at night](/sites/default/files/styles/resource_card_image_360x300_/public/2020-02/telescope-boy-night.jpg?itok=13zWe-Od)
Optical Telescopes
Backgrounders
Learn about the history of telescopes and the function of refracting and reflecting optical telescopes.
![Radio Telescope array at night](/sites/default/files/styles/resource_card_image_360x300_/public/2020-02/radio-telescope-at-night.jpg?itok=Xj9MDhpb)
Radio Astronomy
Backgrounders
Learn about radio astronomy, a type of astronomy that studies objects in space using radio waves and radio telescopes.
![Carl Dixon](/sites/default/files/styles/career_image/public/2020-02/Carl%20Dixon.jpg?itok=asZH3RFI)
Carl Dixon
Career Profiles
Naval Communicator
![Keven Bruce | Tactical Weather Specialist](/sites/default/files/styles/career_image/public/2019-09/Kevin%20Bruce.jpg?itok=-QI0mlRn)
Keven Bruce
Career Profiles
Tactical Weather Specialist
![Alexis Dorais | Analyste en télédétection](/sites/default/files/styles/career_image/public/2019-09/Alexis%20Dorais.jpg?itok=tFxfkVG7)
Alexis Dorais
Career Profiles
Remote Sensing Analyst
![Adult and children looking through telescope](/sites/default/files/styles/resource_card_image_360x300_/public/2019-09/adult_and_children_looking_through_telescope.jpg?itok=eKeL_YGd)
The Optics of Telescopes
Backgrounders
Learn about telescopes, how they work & why they're important to astronomers.
![Why is everything so small down there?](/sites/default/files/2019-08/why-is-everything-so-small-down-there.jpg)
Why is everything so small down there?
Hands-on Activities
Explore how we see things far and near and from different angles. It's all about perspective!
![The Parkes Observatory in New South Wales, Australia](/sites/default/files/styles/resource_card_image_360x300_/public/2019-10/Park_Observatory_NSW_Australia.jpg?itok=K11hu9qK)
The Search for Extraterrestrial Intelligence - and How You Can Help!
STEM Explained
When astronomers search for extraterrestrial life, they often have to listen for radio waves coming from deep space. If you’re interested, you can help!
![Space junk](/sites/default/files/styles/resource_card_image_360x300_/public/2019-10/space-junk-orbiting-earth.jpg?itok=nA6-Kgmi)
Space Junk
STEM Explained
Litter isn't just a problem on Earth. When litter ends up in space, it can cause collisions and other consequences for satellites, the International Space Station and even for people on Earth!
![Screen capture from the video “Dealing With Asteroids and Other Space Hazards”](/sites/default/files/styles/resource_card_image_360x300_/public/2019-09/Asteroids_and_space_hazards.jpg?itok=dCFoyV24)
Dealing with Asteroids and Other Space Hazards
STEM Explained
Find out how asteroids, space debris, and cosmic radiation can be dangerous, and how to monitor them and protect ourselves from these space hazards.