Worlds Archives | Filling Space

What is it like studying faraway worlds like Titan?

Titan, Saturn’s largest moon, is unique in many ways. It is the only moon in our Solar System known to have a thick atmosphere. Other…

Machine Worlds

How did MESSENGER revolutionize our understanding of Mercury?

Editor October 25, 2019 comets exoplanets flybys geology magnetic fields Mariner 10 Mercury NASA planetary science rocky planets

Mercury, one of Earth’s rocky neighbors, is one of our Solar System’s most enigmatic planets. It is notoriously difficult to study due to its close…

Worlds

How does stars’ radioactivity affect the habitability of nearby planets?

Editor August 30, 2019 exoplanets gas giants Habitability habitable zones liquid water radioactivity rocky planets Space Weather terrestrial planets ultracool dwarfs

Stars are dynamic entities. They emit radiation and charged particles that affect the planets that orbit them. This “space weather” is thus an important factor…

Worlds

What do we know about Titan, Saturn’s largest moon?

Editor August 9, 2019 biology geochemistry geology NASA organic molecules physics planetary science Saturn spacecraft Titan

One of the most interesting worlds in this solar system is Titan, the largest moon of Saturn. It has a climate that in some ways…

Worlds

Deflecting Existential Risk with Space Colonization

Editor April 19, 2019 asteroids comets impact craters mass extinctions space arks space colonization space exploration starships the Oort Cloud the Solar System

The first living organism on Earth emerged approximately three and a half billion years ago. Since then, life has evolved into countless forms and colonized…

Worlds

How to Settle the Solar System

Editor April 11, 2019 astronomy Mars Mercury space exploration space habitats spacefaring the asteroid belt the International Space Station Venus

Space is marvelous but hostile. If humans intend to be spacefaring, we must identify and overcome major obstacles before colonizing our Solar System. Some think…

Worlds

The Martian Subsurface: A Shielded Environment for Life?

Editor February 22, 2019 Mars microbial life NASA organic matter seismology subsurface exploration the Jet Propulsion Laboratory the Martian subsurface the Martian surface the Red Planet

Among our solar system’s planets, Mars seems a likely spot for future human habitation. Elon Musk is developing an interplanetary vehicle that may someday…

Worlds

Terraforming: Stranger than Science Fiction

Editor October 12, 2018 biology biospheres ecology ecopoiesis ecopolitics ecosystems HG Wells science fiction terraforming The War of the Worlds

Elon Musk and NASA are quarrelling about whether it is possible to terraform Mars. The debate is an old one. Terraforming (sometimes called ecopoiesis in…