Grades 9-12

When Worlds Diverge

Article

When Worlds Diverge

For all their similarities, Mars possesses unique geophysical traits — traits that early on set Mars on a developmental path distinct from Earth's.

Is the Signature Still Wet?

Article

Is the Signature Still Wet?

A series of satellite photographs taken by NASA's Mars Global Surveyor, which has been mapping Mars since 1999, raise the exciting possibility that liquid water may have existed there very recently.

Article: First Planet Finishes Last

Article

Article: First Planet Finishes Last

Mercury is the most unusual of the four planets closest to the Sun. It’s also the most neglected. Until MESSENGER, it was the only one of the four that hadn’t been comprehensively imaged.

Probability and 2004 MN4: A New Drama

Article

Probability and 2004 MN4: A New Drama

In 2004, news of Asteroid MN4 hit the blogosphere: "So, in summary, there's a 1-in-233 chance of the worst disaster in recorded history happening on April 13, 2029, and a 232-in-233 chance of nothing happening." Take a closer, scientific look.

In Hot Pursuit of Asteroids

Article

In Hot Pursuit of Asteroids

Given the potential for asteroids to literally and figuratively impact life on Earth in a profound way, asteroids have been quite sought after since the first and largest one, Ceres, was discovered in 1801. Learn more.

Article: The 142-Megapixel Digital Camera

Article

Article: The 142-Megapixel Digital Camera

The Sloan Telescope has a digital camera the size of a dishwasher that’s sophisticated enough to capture every luminous object in the northern celestial hemisphere. Take a closer look.

Article: One in a Million

Article

Article: One in a Million

Have you ever stumbled upon a discovery while looking for something completely different? See what surprises astronomers found as part of the Sloan Digital Sky Survey.

Interactive

Interactive: How Far is Far?

This interactive explains how astronomers measure the properties of light from faraway space objects to calculate their distance from Earth. Users click through a series of pages that explain the concepts step-by-step with illustrations and animations.

Article: The Big Questions

Article

Article: The Big Questions

What is the Universe’s arrangement today? What did it look like at its birth? And how did we get from then to now? These are just some of the “Big Questions” astronomers are making headway answering.

SELECT PAGE