Pluto was recategorized from a planet to a dwarf planet in 2006.
(Shutterstock)
A curious kid asks: Why does it matter if Pluto is a planet or a dwarf planet?
The 1833 Leonid Meteor storm, as seen over Niagara Falls.
Edmund Weiß (1888)
Could the Tau Herculid meteor shower put on a spectacular show next week? Only time will tell.
An artist’s concept of an astronaut walking on Mars. But what would happen if the astronaut weren’t wearing a space helmet?
cokada/E+ via Getty Images
Mars is the fourth planet from the Sun and one of our closest neighbors in space. But it’s not a very welcoming place for an Earthling to visit.
There is a U.S. flag on the Moon, but in the future, countries may start to turn access to the Moon and asteroids into serious wealth.
NASA/Neil A. Armstrong
Current trends suggest that powerful nations are defining the rules of resource use in space and satellite access in ways that will make it hard for developing nations to ever catch up.
Pluto, the largest of the dwarf planets. This image was taken by NASA’s New Horizons spacecraft.
NASA/JHUAPL/SwRI
The dwarf planets in our Solar System are cold, dark, far away and full of surprises.
SpaceX
There has never been a dedicated mission sent to the “ice giants”, Uranus and Neptune. But there may be one on the horizon.
Lia Koltyrina/Shutterstock
Humans might one day be able to live somewhere else in the Universe.
ISAS / JAXA
The Hayabusa2 mission brought a piece of asteroid Ryugu back to Earth, where it has helped scientists resolve a long-standing puzzle.
Image of Ryugu taken by the Hayabusa 2 spacecraft in 2018.
JAXA/wikipedia
We may be on the brink of discovering whether water and organic material, which enabled life on Earth, came from asteroids.
SPP 1992 (Patricia Klein)
Most of what we know about planets outside our Solar System relates to gas-giant planets. A new study has identified and characterised a smaller exoplanet.
Curtin University
Tiny pieces of an asteroid have revealed an unlikely origin for much of the water in Earth’s oceans.
The planet Saturn.
viktorov.pro/Shutterstock
Saturn, Jupiter, Neptune and Uranus all have rings.
It only takes light about eight minutes to go from the Sun to Earth.
loops7/E+ via Getty Images
The fastest things ever made by humans are spacecraft, and the fastest spacecraft reached 330,000 mph – only 0.05% the speed of light. But there are ways to go faster.
NASA images/Shutterstock
It can get very cold in space.
A telescope in the outer solar system would be able to do unique science that is impossible closer to the Sun.
Michael Zemcov
Such a mission could be developed soon, allowing astrophysicists to take selfies of the solar system and use the Sun’s gravity as a lens to peer deep into space.
Bruno Gilli/ESO/Wiki Commons
The sky on other planets doesn’t look the same as the sky on Earth does. And that’s because of the different gases in Earth’s atmosphere.
Artist’s rendition of the Jupiter-like planet and its white dwarf star.
W. M. Keck Observatory/Adam Makarenko
In 5 billion years the Sun will collapse. A new discovery suggest some planets may still survive afterwards.
Artist’s impression of BepiColombo during a swing-by of Mercury.
ESA/ATG medialab
What did Mercury look like as BepiColombo swung by?
The Earth is round.
Alistair Berg/DigitalVision via Getty Images
Gravity, mass and centrifugal force all contribute to the final shape of a planet.
NASA / Tim Pyle
By studying the chemical makeup of binary stars, astronomers found many planetary systems are far less peaceful than ours.