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Where is Proxima Centauri?

You probably know by now that a planet has been discovered around the very nearest star. Guy Ottewell shows you where in space that star is.

The calculated orbit of 2016 QA2. Via JPL Small Body Database/ sciencythoughts.blogspot.com.

Hours after discovery, asteroid swept by

Asteroid 2016 QA2 was twice as big as the space rock that entered over Russia in 2013, breaking windows in 6 Russian cities. It passed safely Saturday night.


Success for Juno’s 1st Jupiter flyby

Juno spacecraft arrived at Jupiter on July 4 and has spent some weeks in a testing mode. On Saturday, it came closer to Jupiter than any spacecraft ever has.


Your cosmic suntan

Lie on the beach, and your body is bombarded by light from our sun, and from beyond our galaxy.

This dual view of Jupiter was taken on August 23, 2016, when NASA's Juno spacecraft was 2.8 million miles (4.4 million km) from the gas giant planet on the inbound leg of its initial 53.5-day capture orbit. Image via NASA/JPL-Caltech/SwRI/MSSS

Juno soars closest to Jupiter August 27

The Juno spacecraft will be about 2,500 miles (4,200 km) above Jupiter’s swirling clouds. No other spacecraft has ever orbited Jupiter this closely.

NASA astronaut Tim Kopra captured an image of the SpaceX Dragon spacecraft, on the company's eighth Commercial Resupply Services mission, from the Cupola Module of the International Space Station during Expedition 47 in April 2016. Image via NASA

Watch SpaceX Dragon depart ISS Friday

Live coverage Friday of cargo ship’s departure from International Space Station. Begins at 5:45 a.m. EDT (9:45 UTC).

View larger. | Artist's concept of a view of the surface of the planet Proxima b, a newly found planet orbiting in the habitable zone of Proxima Centauri, the next-nearest star. The double star Alpha Centauri AB also appears in the image to the upper-right of Proxima itself. Proxima b is a little more massive than Earth. Image via ESO.

Proxima Centauri’s awesome new planet

The newly found planet for Proxima Centauri, our sun’s nearest neighbor among the stars, is revealed as the closest possible abode for alien life.

Pluto via New Horizons spacecraft on July 14, 2015.

Today in science: Pluto the dwarf planet

August 24, 2016 is the 10th anniversary of astronomers’ announcement of Pluto’s demotion to dwarf planet. The decision caused a shock wave around the world.

Hoax image via social media.

No double moon in 2016, or ever

We thought we might get through this summer without the dumb hoax about Mars as big as a full moon rearing its head. But, no.

First view of Earth from the moon, courtesy NASA/Lunar Orbiter 1.

Today in science: Earth from the moon

First photo of Earth from the moon, released it in 1966. Later, NASA used modern digital technology to restore the photo, revealing more detail.

Image via NASA.

NASA prepares to sample an asteroid

On September 8, NASA will launch its first sample return mission to an asteroid. A robot arm will reach out, snag some asteroid bits and return them to Earth.

Path of 2017 total solar eclipse, via Fred Espenak.

Total eclipse of sun: August 21, 2017

One year from today … the 1st total solar eclipse visible from the contiguous U.S. since 1979. Start planning now!


Dates of lunar and solar eclipses in 2016

The next eclipse is an annular solar eclipse on September 1, 2016.

Image via NASA

Watch spacewalk live August 19

Two ISS astronauts will perform a spacewalk on Friday. NASA TV’s live coverage starts at 6:30 a.m. EDT (10:30 UTC) and lasts about eight hours.

Phobos, via Viking 1.  Image Credit:  NASA

Today in science: A moon for Mars

American astronomer Asaph Hall discovered Phobos, one of the two Martian moons, on this date in 1877. Did he imagine how well we’d see Mars’ moons today?

Image via www.sciencealert.com

Physicists confirm a possible 5th force

“If true, it’s revolutionary,” said Jonathan Feng, professor of physics and astronomy at University of California, Irvine and lead author of the new study.

This image shows the famous Pleiades cluster of stars as seen through the eyes of WISE, or NASA's Wide-field Infrared Survey Explorer.Image credit: NASA/JPL-Caltech/UCLA

Astronomers aim Kepler at the Pleiades

The famous planet-hunting Kepler spacecraft peered toward the beautiful Pleiades star cluster and measured the spin rates of hundreds of Pleiades stars.

An artist's concept of a Dyson sphere. Image via CapnHack, via energyphysics.wikispaces.com.

Tabby’s Star: More weirdness

Some astronomers think this star may have an alien megastructure – an energy-gathering Dyson sphere – around it. Here’s the latest.

White circles denote areas pinged by Cassini’s radar. Image via NASA JPL.

Saturn’s moon Titan has flooded canyons

They’re steep-sided canyons with liquid in them, but the liquid isn’t water. Instead, it’s liquid hydrocarbons.

Geminid meteor, Lovund, Nordland, Norway.
 Photo via Tommy Eliassen.

How high up do meteors start glowing?

Meteors begin to glow almost as soon as they hit Earth’s atmosphere, but tend to vaporize (burn up completely) at varying altitudes.