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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.

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 to 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.


How long to travel to Alpha Centauri?

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

Jan Oort. Copyright Leiden Observatory. Used with permission.

This date in science: Jan Oort’s birthday

Visualize a vast reservoir of icy comets on the outskirts of our solar system. That’s what Jan Oort did in 1950, and why the Oort Cloud bears his name.


What makes a red rainbow?

Red rainbows happen when the sun is on the horizon. They’re created in much the same process that causes a sunset or sunrise to look red.

Discovery image for first-ever known moon orbiting the remote dwarf planet Makemake.

Dwarf planet Makemake has a moon

This Hubble Space Telescope image reveals the first moon ever discovered around little Makemake, in the outermost region of our solar system.

Venus Express aerobraking. Image credit: ESA - C. Carreau

What Venus Express learned by aerobraking

Results from the Venus Express spacecraft, obtained when – in the craft’s final months – it surfed the dense atmosphere of Venus.