Out of this World Crossword

2. Organizations are considering ideas such as ________, harpoons, tethers, and robotic arms to remove the orbital debris that surrounds us.
5. In space, blue skies appear __________ because of a lack of oxygen.
6. A solar system comprises of a ________ which is orbited by planets.
8. __________ 1 is the probe furthest from Earth, now reaching interstellar space!
10. Pluto is an example of a _______ planet, a planet which is too small to be considered a “normal” planet.
11. The _______ space telescope is the oldest telescope in space.
12. The furthest humans have ever traveled in space was during the __________ 13 mission.
13. The _________ Space Station was sent into space in 1998 and was not officially completed until 2011. Maintenance missions still run to improve the station and keep it running.

1. Orbital ______ is caused from both natural causes such as meteoroids as well as human trash such as broken and abandoned spacecraft.
3. Our star is called the ______.
4. The force of ________ pulls nebulae (star dust) together to form the core of the star.
5. Orbit is a __________ balance between an object's forward energy and the pull of gravity on that object.
7. The ________ of a red supergiant star is quite aggressive and explosive.
9. A _______ is anything that orbits a planet or a star, not always an orbiting machine sending us signals from space.