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How long to travel to Alpha Centauri?

The distances between stars are vast, which is why star travel is so far. Read here about conventional propulsion and warp drives, plus about Breakthrough Starshot’s new idea to send nanostarships to Alpha Centauri.

What’s the weather like on Proxima b?

The nearest known exoplanet – orbiting the star Proxima Centauri – is only 4.2 light-years away. Does it have liquid water? An atmosphere? Weather? Scientists just announced the first tentative steps to explore those possibilities.

Planet circus in May, with explanation

A beautiful spatial view of our solar system from Guy Ottewell, showing the planets’ paths along their orbits in approximately mid-May, 2017, with sightlines to them from the Earth.

Eta Aquarid over Mount Bromo

Cool short video of an early morning Eta Aquarid meteor over Mount Bromo in Indonesia, by Justin Ng. Take a few seconds and enjoy!

Watch 200th spacewalk Friday

Watch 2 astronauts perform landmark 200th ISS spacewalk on Friday, May 12. Live coverage begins at 6:30 a.m. EDT (10:30 UTC). Links to viewing here.

Astronomers find waves in Io’s lava lake

New data on the massive molten lake on Jupiter’s moon Io – most volcanically active world in our solar system – suggest 2 lava waves per day, slowly sweeping west to east.

Asteroid 2014 JO25: What we learned

This article from NASA’s Center for Near-Earth Object Studies provides fresh details on the closest approach by a large asteroid since 2004 … and shows you how science works.

What’s a safe distance between us and a supernova?

And how many potentially exploding stars are located within the unsafe distance?

The last of Hubble’s Frontier Fields

With a final observation of remote galaxy cluster Abell 370, the Hubble Space Telescope’s mind-stretching Frontier Fields program came to an end.

X-ray tsunami in Perseus galaxy cluster

Not so very long ago or far away in astronomical terms, a near-miss between titanic galaxy clusters might have set into motion an immense wave of hot gas.