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Old under-ice volcanoes on Mars

An oddly textured region of southern Mars is not ice-covered today. Yet landforms here – and now certain minerals – are associated with under-ice volcanoes.

Artist's conception of Planet Nine, in the far outer solar system. In this image, the star in the lower right is our sun. Image via Caltech/R. Hurt (IPAC)

Why Planet 9 shouldn’t exist

Earlier this year, scientists presented evidence for a Planet Nine in the far outer solar system. Scientists think it exists, but – if so – how did it get there?

Neil Armstrong, July 20, 1969

Today in science: Neil Armstrong’s close call

On May 6, 1968 – more than a year before his famous first moonwalk – Neil Armstrong narrowly escaped disaster while training in the Lunar Landing Research Vehicle.

Comet Halley's position in May, 2016. The view is from the north side of the solar system, whereby the planets orbit the sun in a counterclockwise direction - but Halley's Comet orbits the sun clockwise. Click here for Comet Halley's present position, or if you'd like, change the date to view its position in any chosen year.

Comet Halley, parent of 2 meteor showers

The Eta Aquarid meteor shower was spawned by the famous Comet Halley. But Halley spawned another meteor shower, too.

Sunlight glints off of Titan's northern seas this near-infrared, color mosaic from NASA's Cassini spacecraft. Image credit: NASA/JPL/Univ. Arizona/Univ. Idaho

A pure methane sea on Titan

We knew that Saturn’s moon Titan had seas and lakes of liquid hydrocarbons, but their exact composition was unknown until recently.

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Shortest lunar month of 2016 starts May 6

Although the lunar month has a mean period of 29 days 12 hours and 44 minutes, the actual length varies throughout the year. Lengths of lunar months in 2016.

Artist's impression of the unique object C/2014 S3 (PANSTARRS). Observations with ESO’s Very Large Telescope, and the Canada France Hawai`i Telescope, show that this is the first object to be discovered that is on a long-period cometary orbit, but that has the characteristics of a pristine inner Solar System asteroid. It may provide important clues about how the Solar System formed. Because the object has spent most of its life away from the inner Solar System it suffered very few collisions, and its surface displays few or no craters. As it formed in the same region as the Earth did, it is mostly rocky, and therefore has only very limited cometary activity.

Orbit like a comet, rocky like an asteroid

They’re calling it a Manx comet, after the cats with no tails. It may have formed in the inner solar system and been ejected outward.

View larger. | As January, 2016, opens, there are four planets in the predawn sky.  Ben Zavala caught them on January 4, 2015.  Thanks, Ben!

Astronomical events in 2016

A month by month listing of major moon phases, conjunctions, oppositions, meteor showers and other important dates, from astronomer Fred Espenak.

Photo via BreakthroughInitiatives.org.

Breakthrough Starshot aims for Alpha Centauri

Breakthrough Starshot seeks proof of concept for a 100-million-mile-per-hour mission – using light-propelled nanocrafts – to reach the nearest star in 20 years.

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How long would it take to get to Alpha Centauri?

Read about star travel via conventional propulsion, warp drives, and more.