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More evidence for a Planet 9

No new large planet on the outskirts of our solar system has yet been discovered, although evidence is building, astronomers say. By the way, if Planet 9 does exist … it’s definitely not headed our way.

What are gravitational waves?

If you understand how a trampoline works, you’ll be able to understand what gravitational waves are.

Gravitational waves, and more, from merging neutron stars

On Monday, LIGO and Virgo announced the 1st detection of gravitational waves produced by colliding neutron stars, and 1st observed in both gravitational waves and light. “It ushers in a new era in astronomy.”

Egg-shaped Haumea has a ring

Dwarf planet Haumea – which orbits our sun in Pluto’s realm of the solar system – has become the first trans-Neptunian object known to be encircled by a ring.

Intense storms batter Saturn moon Titan

“I would have thought these would be once-a-millennium events, if even that,” said a researcher. Instead, the storms on Titan happen about once a Saturn-year, creating massive floods in an otherwise-desert terrain.

Peering to the Milky Way’s far side

Astronomers use parallax to directly measure the distance to a star-forming region on the opposite side of our Milky Way galaxy, nearly doubling the previous distance record.

Today in science: Proxima Centauri

Astronomers announced the discovery of Proxima Centauri – next-nearest to our sun – on this date in 1915.

Asteroid to sweep close October 11-12

Asteroid 2012 TC4 is being used as a test of Earth’s global asteroid defense system. How to see it online.

This region on Mars may hold clues to earthly life

Evidence for deep-sea hydrothermal vents in the Eridania basin of southern Mars. Even if Mars never had life, this region may tell us about the type of environment where life on Earth may have begun.

EarthSky’s 2017 meteor shower guide

Draconids have passed, mostly in bright moonlight. Orionids, Taurids, Leonids and Geminids ahead! Orionids peak before dawn October 21, in a moon-free sky.

Forecast for Mercury: Morning micro-meteor showers

Mercury – with only the thinnest of atmospheres – has a continuous rain of micro-meteors wherever on the planet dawn is breaking.

Did the moon once have air?

We know that ancient lunar volcanos spewed lava. Gases rising from the lava might have accumulated around the moon to form a temporary atmosphere, 3 to 4 billion years ago.

5 new pairs of merging supermassive black holes

Merging black holes are the sorts of catastrophic events that produce the strongest gravitational waves. Scientists just announced 5 new pairs, in the centers of distant galaxies.

Today in science: 1st planet orbiting a sunlike star

On October 6, 1995, astronomers announced 51 Pegasi b, a planet about half the mass of Jupiter, orbiting a star not unlike our sun.

Is dust what’s dimming Tabby’s Star?

Astronomers say they’ve found a smoking gun that rules out the idea of an energy-harvesting megastructure or Dyson sphere – built by an alien civilization – surrounding Tabby’s Star.

Watch ISS spacewalk October 5

It’s the first of 3 ISS spacewalks this month.

Large storm on sun sparked global aurora on Mars

Scientists said the solar event “lit up Mars like a light bulb.” It was the biggest event of its kind so far observed by spacecraft in Mars orbit and on the surface.

Moon and planet-rise, seen from space

This timelapse video shows a peaceful and breathless moonrise from the International Space Station, with Venus, Mars and Mercury also in view.

Farthest active inbound comet yet

Most comets become active only when near the sun. This one is active, but distant, between the orbits of Saturn and Uranus, where sunlight is 1/225th as bright as seen from Earth.

5 myths about the moon

Moon myths, take that! Here are 5 of the most common myths about our moon explained.