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Breakthrough Starshot aims for Alpha Centauri

Photo via BreakthroughInitiatives.org.

The dream of traveling to the stars is alive and well. Artist’s concept via BreakthroughInitiatives.org.

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 would it take to get to Alpha Centauri?

Credit: Mark Rademaker/Mike Okuda/Harold White/NASA.

What a spaceship with warp drive might look like. Credit: Mark Rademaker/Mike Okuda/Harold White/NASA.

Alpha Centauri is the nearest star system to our sun at 4.3 light-years away. That’s about 25 trillion miles (40 trillion km) away from Earth – nearly 300,000 times the distance from the Earth to the sun. How might we travel to Alpha Centauri, the next-nearest star? And how long would it take to get there? Read about star travel via conventional propulsion, warp drives, and more.

Did Earth’s magnetic field collapse for 2 hours on April 23?

An illustration of Earth’s magnetic field shielding our planet from solar particles. Image via NASA/GSFC/SVS.

An illustration of Earth’s magnetic field shielding our planet from solar particles. Image via NASA/GSFC/SVS.

No, Earth’s magnetic field did not collapse for 2 hours on April 23. The erroneous story – which is still spreading – came from a glitch in a computer simulation.

This date in science: Jan Oort’s birthday

Jan Oort. Copyright Leiden Observatory. Used with permission.

Jan Oort. Copyright Leiden Observatory. Used with permission.

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?

Frances Pelletier caught this double red rainbow - and the planet Venus - on February 9, 2016 from Myrtle Beach, South Carolina.

Frances Pelletier caught this double red rainbow on February 9, 2016 from Myrtle Beach, South Carolina.

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. Details – and more photos – inside.

Dwarf planet Makemake has a moon

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

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

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

Watch NASA build James Webb Space Telescope

Image from live webcam - April 26, 2016 - of the James Webb Space Telescope, now under construction at Goddard Space Flight Center.

Image from live webcam – April 26, 2016 – of the James Webb Space Telescope, now under construction at Goddard Space Flight Center.

The JWST mirror covers off for a few days this week, and webcams are set up at Goddard Space Flight Center. Watch! Link inside.

Chernobyl worst nuclear accident of all time

Health effects of the Chernobyl disaster are still felt 30 years on. Photo credit: Garanich/Reuters

Health effects of the Chernobyl disaster are still felt 30 years on. Photo credit: Garanich/Reuters

The meltdown at the Chernobyl Nuclear Power Plant happened 30 years ago today – April 26, 1986. The disaster exposed 572 million people to radiation. No other nuclear accident holds a candle to that level of public health impact.

What Venus Express learned by aerobraking

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

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

ESA has announced some final results sent back by Venus Express obtained when – in the spacecraft’s final months – it surfed in Venus’ dense atmosphere. The data show the planet’s atmosphere to be rippling with atmospheric waves and colder than anywhere on Earth.

Moon rocks reveal nearby supernova

Moon rocks collected b Apollo astronauts have been found to contain an element created only by supernovae. Here, Apollo 12-astronaut Alan Bean takes a sample of the lunar surface. Photo via NASA.

Moon rocks collected by Apollo astronauts have been found to contain iron-60, which is created only by supernovae. Here, Apollo 12-astronaut Alan Bean takes a sample of the lunar surface. Photo via NASA.

Scientists have discovered iron-60, a form of iron only created in supernovae, in moon rocks collected by Apollo astronauts. It supports an earlier finding that – 2 million years ago – a supernova exploded only 300 light-years away.