A nearly face-on disk of gas and dust, with interesting gaps.

Do all planets orbit in a flat plane around their suns?

The major planets in our solar system orbit, more or less, in a single plane. That’s why you can look for them along the same sky path traveled by the sun and moon. Is the same true for exoplanets in distant solar systems?

Contemplate the apex of the sun’s way

Our sun moves around the center of the galaxy, toward the star Vega. Astronomers call this motion the apex of the sun’s way. One circuit – about 230 million years – is called a cosmic year.

A dim distant sun and small rocky bodies moving around it.

Mystery orbits don’t require a Planet 9, researchers say

Here’s an alternative explanation to the Planet 9 hypothesis, the idea that a large undiscovered planet in the outer solar system is pulling on some small outer worlds, distorting their orbits.

Stargazing destinations: Alberta

Skywatchers! Check out this first video in the Chasing Darkness series, a stargazing destination guide. This episode – dark sky preserves in Alberta, Canada.

Why no eclipse every full and new moon?

In 2019, there are 13 new moons and 12 full moons, but only 5 eclipses – 3 solar and 2 lunar.

Identify stars in the Winter Circle

Go outside, and look for the waxing gibbous moon tonight. Then notice the stars nearby. Tonight’s moon is within the Winter Circle stars.

dark fossil outline in yellow stone

Did life on land arrive far earlier than thought?

New clues from fossils from the oldest soils on Earth suggest that multicellular, land-dwelling organisms might have emerged much earlier than we thought.

Blown-up image of a very distant galaxy, with the location of the flare-up indicated by tick marks.

Holy cow! Astronomers puzzle over a mysterious blast

Astronomers are arguing over a brief and unusual flash in the night sky from earlier this year. The call it the Cow. One group argues it was a monster black hole shredding a passing star. The other argues it might have been a black hole being born.

Orange sphere with golden shoots.

Probing the magnetar at the center of our galaxy

A new study analyzes pulses of radio waves coming from a magnetar – a rotating, dense, dead star with a strong magnetic field – located near the supermassive black hole at the heart of the Milky Way.

A winding river of stars called Eridanus

Why search for such a faint constellation? Only because it’s very beautiful. Plus seeing Eridanus can give you a kinship with stargazers from centuries ago.

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