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Twin Jet Nebula

View larger. | The Twin Jet Nebula, aka PN M2-9, is what's called a planetary nebula, formed, in this case, when the central object is not a single star, but a binary system, Studies have shown that the nebula’s size increases with time, and measurements of this rate of increase suggest that the stellar outburst that formed the lobes occurred just 1200 years ago.  Image via ESA/Hubble and NASA.

View larger. | The Twin Jet Nebula, aka PN M2-9, is what’s called a planetary nebula, formed, in this case, when the central object is not one star, but two stars. Hubble Space Telescope image via ESA/Hubble and NASA.

Did glaciers lure wolves back to California?

Gray wolves in snow. Image credit: University of Buffalo

Gray wolves in snow. Image credit: University of Buffalo

More than 90 years after California’s last wolf was killed, a pack has been observed near Mt. Shasta. Are the mountain’s glaciers a reason the wolves chose this location?

See Earth’s shadow and Belt of Venus

Earth's shadow is the blue-grey band closest to the horizon.  The Belt of Venus is the pink band above the shadow.

Earth’s shadow is the blue-grey band closest to the horizon. The Belt of Venus is the pink band above the shadow.

In both the evening and morning sky, try watching for Earth’s shadow. Earth’s shadow is a deep blue-grey, darker than the twilight sky. The pink band above the shadow – in the east after sunset, or west before dawn – is called the Belt of Venus.

Origin of Saturn’s F ring and shepherd moons

View larger. | The narrow F ring located just outside of the outer edge of the main rings. Two satellites sandwiching the F ring slightly above and to the left of the center of the image are the shepherd satellites Prometheus (inner orbit) and Pandora (outer orbit).

The narrow F ring located just outside of the outer edge of the main rings. Two satellites sandwiching the F ring slightly above and to the left of the center of the image are the shepherd satellites Prometheus (inner orbit) and Pandora (outer orbit).

Scientists at Kobe University in Japan this week announced results of a study showing that Saturn’s F ring and its shepherd satellites are natural by-products of the final stage of formation of Saturn’s satellites. The F ring is the outermost of Saturn’s rings. It is perhaps the most active ring in our solar system, with features changing on a timescale of hours.

New images from Dawn mission to Ceres

View larger. | Image acquired by the Dawn spacecraft on August 19, 2015.

Sharpened, enlarged crop of the mountain 1 Ceres, acquired by the Dawn spacecraft on August 19, 2015. Dawn was 910 miles (1,470 km) from Ceres at the time. Image via NASA/JPL-Caltech/UCLA/MPS/DLR/IDA.

Enjoying the Dawn mission to dwarf planet Ceres? Welcome to HAMO (High Altitude Mapping Orbit). Dawn has now moved to within about 900 miles (1,500 km) from Ceres. This phase of the mission has just begun and promises to reveal even more about this little world. Here are some early images from that closer orbit.

Want to see Earth’s super predator? Look in the mirror.

Rope trawl for midwater trawling. Photo credit: NOAA

Rope trawl for midwater trawling. Photo credit: NOAA

Our efficient killing technologies have given rise to the human super predator. Our impacts are as extreme as our behavior, says study.

Liquid water elsewhere in our solar system?

A frozen lake of water-ice on the floor of a 35 km wide impact crater on Mars. Image credit: ESA/DLR/FU Berlin (G. Neukum)

ESA’s Mars Express obtained this perspective view of an unnamed impact crater located on Vastitas Borealis, a broad plain that covers much of Mars’ far northern latitudes. The crater is 20 miles (35 km) wide. The circular patch of bright material located at the center of the crater is residual water ice. Image credit: ESA/DLR/FU Berlin (G. Neukum).

If so, where are likely to find it and could we ever get to it? And would we be able to drink it? A planetary geologist discusses these issues.

Graceful arc of Venus before dawn

Check out this wonderful animation from Larry Koehn of the website shadowandsubstance.com. It shows Venus in the morning sky 45 minutes before sunrise from August 2015 through March 2016.

Orion the Hunter and Sirius the Dog Star

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Every year, during the last week of August, a first hint of the changing of the seasons can be seen in the predawn sky: Orion the Hunter and Sirius the Dog Star. Orion the Hunter rises before dawn at this time of year, recognizable for the short straight line of three stars that make up Orion’s Belt. And the sky’s brightest star Sirius – sometimes called the Dog Star – follows Orion into the sky at or close to dawn.

Rediscovering a rare South Pacific nautilus

The nautilus known as Allonautilus scrobiculatus off the coast of Ndrova Island in Papua New Guinea. Image via Peter Ward

The nautilus known as Allonautilus scrobiculatus off the coast of Ndrova Island in Papua New Guinea. Image via Peter Ward

A University of Washington biologist has encountered what he considers one of the world’s rarest animals. It’s a species of nautilus called Allonautilus scrobiculatus. Peter Ward and a colleague originally discovered this nautilus species in 1984 off Ndrova Island in Papua New Guinea. Then no one saw this creature again for over 30 years.