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An international team of scientists has found evidence of a series of massive supernova explosions near our solar system, which showered Earth with radioactive debris. The scientists found radioactive iron-60 in sediment and crust samples taken from the Pacific, Atlantic and Indian Oceans. The iron-60 was concentrated in a period between 3.2 and 1.7 million years ago, which is relatively recent in astronomical terms, said research leader Dr Anton Wallner from The Australian National University (ANU). "We were very surprised that there was debris clearly spread across 1.5 million years," said Dr Wallner, a nuclear physicist in the ANU Research...

Explanation: Jupiter has auroras. Like near the Earth, the magnetic field of our Solar System's largest planet compresses when impacted by a gust of charged particles from the Sun. This magnetic compression funnels charged particles towards Jupiter's poles and down into the atmosphere. There, electrons are temporarily excited or knocked away from atmospheric gases, after which, when de-exciting or recombining with atmospheric ions, auroral light is emitted. The featured illustration portrays the magnificent magnetosphere around Jupiter in action. In the inset image released last month, the Earth-orbiting Chandra X-ray Observatory shows unexpectedly powerful X-ray light emitted by Jovian auroras, depicted...

Explanation: Why might you want to visit super-earth Cancri 55 e? Its extremely hot climate would be a deterrent, and fresh lava flows might be common. Discovered in 2004, the planet Cancri 55 e has twice the diameter of our Earth and about 10 times Earth's mass. The planet orbits its 40 light-year distant Sun-like star well inside the orbit of Mercury, so close that it is tidally locked, meaning that it always keeps the same face toward the object it orbits -- like our Moon does as it orbits the Earth. Astronomers have recently measured temperature changes on this...

Explanation: Is this the real world? Or is it just fantasy? The truth started with a dream -- a dream that the spectacular Seljarlandsfoss waterfall in southern Iceland could be photographed with a backdrop of an aurora-filled sky. Soon after a promising space weather report, the visionary astrophotographer and his partner sprang into action. After arriving, capturing an image of the background sky, complete with a cool green aurora, turned out to be the easy part. The hard part was capturing the waterfall itself, for one reason because mist kept fogging the lens! Easy come, easy go -- it took...

Explanation: It's the bubble versus the cloud. NGC 7635, the Bubble Nebula, is being pushed out by the stellar wind of massive central star BD+602522. Next door, though, lives a giant molecular cloud, visible to the right. At this place in space, an irresistible force meets an immovable object in an interesting way. The cloud is able to contain the expansion of the bubble gas, but gets blasted by the hot radiation from the bubble's central star. The radiation heats up dense regions of the molecular cloud causing it to glow. The Bubble Nebula, featured here in scientifically mapped colors...

Explanation: Get out your red/blue glasses and gaze across a mountainous region informally known as Tartarus Dorsa. This scene sprawls some 300 kilometers (about 180 miles) across the Plutonian landscape. The color anaglyph creates a stereo view by combining parts of two images taken about 14 minutes apart during the New Horizons historic flyby of Pluto last July. Along with shadows near the terminator, or line between Pluto's dim day and night, the 3D perspective emphasizes the alignment of narrow, steep ridges. The region's remarkable bladed landforms typically extend 500 meters high and are 3 to 5 kilometers apart. Referring...

This artist's concept of HD 1885 Ab, the first known planet to reside in a triple-star system, would have a similar sunset to KELT-4Ab. Both systems host a pair of stars distantly orbiting the planet-hosting single sun. Credit: NASA/JPL-Caltech ===================================================================================================================== A team of researchers working at the Harvard-Smithsonian Center for Astrophysics has announced the finding of a triple-star system—one that also as has a stable orbit planet in it. In their paper published in The Astronomical Journal, the team describes how they came to see that a binary system once thought to be a single star, was actually a pair...

Explanation: Looking for an interplanetary vacation destination? Consider a visit to Europa, one of the Solar System's most tantalizing moons. Ice-covered Europa follows an elliptical path in its 85 hour orbit around our ruling gas giant Jupiter. Heat generated from strong tidal flexing by Jupiter's gravity keeps Europa's salty subsurface ocean liquid all year round. That also means even in the absence of sunlight Europa has energy that could support simple life forms. Unfortunately, it is currently not possible to make reservations at restaurants on Europa, where you might enjoy a dish of the local extreme shrimp. But you can...

'Laser Cloak' Could Hide Earth from Evil Aliens A new paper describes how laser beams could disrupt measurements of Earth's orbit around the sun, potentially deceiving inquisitive aliens. Here, a 22W laser used for adaptive optics shines from the Very Large Telescope in Chile. Credit: ESO/G. Hüdepohl A simple laser beam could disrupt aliens' observations of Earth, making it look like there's nobody home on the third rock from the sun, a new study suggests. David Kipping, an astronomer at Columbia University in New York, said he first considered this idea when he heard about the strangely dimming star that...

Explanation: Welcome to an equatorial night. This remarkable 24 frame night skyscape was captured from Maba Beach on the Indonesian island of Halmahera during the evening of March 4. Seen from a mere 0.7 degrees northern latitude, both famous northern and southern asterisms and navigational aids lie within the panoramic view. The Big Dipper is on the far left and Southern Cross at the far right. Beyond the fading campfire on that night a yellow-orange celestial triangle is set by Mars, Antares, and Saturn. It stands above the rising central Milky Way, or "Miett" in the local Maba language. Of...

But good luck breathing in the bone-crushing gravity.A newly discovered star is unlike any ever found. With an outermost layer of 99.9 percent pure oxygen, its atmosphere is the most oxygen-rich in the known universe. Heck, it makes Earth's meager 21 percent look downright suffocating. The strange stellar oddity is a radically new type of white dwarf star, and was discovered by a team of Brazilian astronomers led by Kepler de Souza Oliveira at the Federal University of Rio Grande do Sul in Brazil. The star is unique in the known pool of 32,000 white dwarf stars, and is the...

New research suggests that some of Saturn's icy moons, as well as its famous rings, might be modern adornments. Their dramatic birth may have taken place a mere hundred million years ago, more recent than the reign of many dinosaurs... While Saturn's rings have been known since the 1600s, there's still debate about their age. The straightforward assumption is that they are primordial -- as old as the planet itself, which is more than four billion years. However, in 2012, French astronomers found that tidal effects -- the gravitational interaction of the inner moons with fluids deep in Saturn's interior...

Explanation: Fantastic shapes lurk in clouds of glowing gas in the giant star forming region NGC 6188. The emission nebula is found about 4,000 light years away near the edge of a large molecular cloud unseen at visible wavelengths, in the southern constellation Ara. Massive, young stars of the embedded Ara OB1 association were formed in that region only a few million years ago, sculpting the dark shapes and powering the nebular glow with stellar winds and intense ultraviolet radiation. The recent star formation itself was likely triggered by winds and supernova explosions, from previous generations of massive stars, that...

Explanation: Point or tilt to see a spectacular view of Mars visible to the Curiosity rover last December. In the foreground, part of Curiosity itself is visible, including its dusty sundial. Starting about seven meters back, the robotic rover is seen posing in front of a 5-meter tall dark sand dune named Namib, one of many dunes that span Bagnold field. Further in the distance is the summit of Mt. Sharp, the 5.5-kilometer peak at the center of 150-km wide Gale crater, the crater where Curiosity landed a few years ago. The featured composite spans a full 360-degrees around by...

Explanation: The southern part of Orion, the famous constellation and mythical hunter, appears quite picturesque posing here over a famous volcano. Located in the Canary Islands off the northwest coast of Africa, the snow-peaked Teide is one of the largest volcanoes on Earth. Lights from a group planning to summit Teide before dawn are visible below the volcano's peak. In this composite of exposures taken from the same location one night last month, the three iconic belt stars of Orion are seen just above the peak, while the famous Orion Nebula and the rest of Orion's sword are visible beyond...

And this new planet could be huge. Back in January, the astronomer who led the charge to have Pluto demoted to dwarf planet status announced that he’d just found evidence that a huge, icy planet could be lurking on the edge of the Solar System, just past Neptune. Mike Brown, a planetary astronomer at Caltech University, estimated that the hypothetical 'Planet Nine' appears to be circling the Sun on a super-elongated orbit that takes an incredible 10,000 to 20,000 years to complete. And now, thanks to a newly detected Kuiper Belt Object (KBO) that’s acting really strange, Brown says the...

Figure 9 from “A Roadmap to Interstellar Flight”Guest essay by Eric WorrallAn American scientist has made a remarkable conceptual breakthrough, a design for a non nuclear relativistic launcher, capable of accelerating thousands of deep space probes per year to 0.25C; fast enough to reach the nearest stars in 15 years. The system is extremely scalable – you could start with a small, low cost proof of concept launcher, and work up to bigger devices, capable of launching substantial probes into interstellar space. The system also has a practical alternative use – the full size version is powerful enough to deflect...

Earth is often struck by solar eruptions. These eruptions consist of energetic particles that are hurled away from the Sun into space, where those directed towards Earth encounter the magnetic field around our planet. When these eruptions interact with Earth's magnetic field they cause beautiful auroras. A poetic phenomenon that reminds us, that our closest star is an unpredictable neighbor. When the Sun pours out gigantic amounts of hot plasma during the large solar eruptions, it may have severe consequences on Earth. Solar eruptions are, however, nothing compared to the eruption we see on other stars, the so-called 'superflares'. Superflares...

On Saturday, Japan lost contact with its newest space telescope, called Hitomi or ASTRO-H. The telescope, which includes an instrument from NASA, was intended to study the high-energy universe in X-rays and gamma rays, and observe such objects as supermassive black holes and galaxy clusters. Radar observations Sunday indicated that Hitomi, which launched on February 17, is in at least five pieces—and a plot of its orbit revealed a dramatic change on March 26, the date JAXA lost contact with the spacecraft. That means, says astrophysicist Jonathan McDowell, that some kind of “energetic event” has occurred—something more than a simple...

Explanation: How massive can a normal star be? Estimates made from distance, brightness and standard solar models had given one star in the open cluster Pismis 24 over 200 times the mass of our Sun, making it one of the most massive stars known. This star is the brightest object located just above the gas front in the featured image. Close inspection of images taken with the Hubble Space Telescope, however, have shown that Pismis 24-1 derives its brilliant luminosity not from a single star but from three at least. Component stars would still remain near 100 solar masses, making...