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Full-sphere, 360-degree ISS transit

Super cool, interactive image of a transit across the sky of the International Space Station – from May 26, 2017 – by Project Nightflight of Austria.

Two big asteroids to pass safely

Radar astronomers are peering toward asteroid 2017 CS, closest on May 29. Another asteroid – 418094 (2007 WV4) – will be closest June 1. Charts here for Saturday night, for 8-inch or larger ‘scopes!

Today in science: Kennedy’s moon speech

On May 25, 1961, John F. Kennedy gave a stirring speech to a joint session of Congress, inspiring a nation to land humans on the moon with a decade.

What is a supermoon?

By at least 1 definition, the year 2017 has 4 supermoons. Three are new moons and not visible in our sky. The only full moon supermoon of 2017 will come in December.

Mystery light shines near Cygnus A core

When astronomers aimed the Very Large Array at the well-studied galaxy Cygnus A, they were surprised to find a bright new object near the galaxy’s core. Supernova explosion, or a second supermassive black hole?

Brown dwarf launches a vast jet

For the first time, astronomers have found a spectacularly long jet – nearly a light-year long – from a brown dwarf.

Does our sun have a name?

You’ve probably heard star names, such as Polaris or Betelgeuse. But what about our star? Does the sun have a name, and if so what is it?

See Ceres opposite the sun

Dawn mission specialists maneuvered the spacecraft into a special orbit, so that it could look down on Ceres’ famous bright spots from a position known to astronomers as opposition.

A moon for the 3rd-largest dwarf planet

So many moons! With the discovery of a moon for 2007 OR10, most known dwarf planets in the Kuiper Belt – larger than 600 miles across – now are known to have companions.

A giant magnetic bridge between galaxies

Known as the Magellanic Bridge, it’s a huge stream of neutral gas stretching 75,000 light-years between the 2 Magellanic Clouds, which orbit our Milky Way.

What is the electromagnetic spectrum?

The electromagnetic spectrum describes all the wavelengths of light. From dark nebulae to exploding stars, it reveals an otherwise invisible universe.

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.