The Large Magellanic Cloud Stole one of its Globular Clusters

The Milky Way with the Small and Large Magellanic Clouds on the left. Image Credit: ESO/Y. Beletsky. CC 4.0

Astronomers have known for years that galaxies are cannibalistic. Massive galaxies like our own Milky Way have gained mass by absorbing smaller neighbours.

Now it looks like smaller galaxies like the Large Magellanic Cloud have also feasted on smaller neighbours.

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Something Really Wants our Attention. One Object Released 1,652 Fast Radio Bursts in 47 Days

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The energetic phenomena known as Fast Radio Bursts (FRBs) are one of the greatest cosmic mysteries today. These mysterious flashes of light are visible in the radio wave part of the spectrum and usually last only a few milliseconds before fading away forever. Since the first FRB was observed in 2007, astronomers have looked forward to the day when instruments of sufficient sensitivity would be able to detect them regularly.

That day has arrived with the completion of the 500-Meter FAST Radio Telescope (aka. Tianyan, “Eye of Heaven”). Since it commenced operations, this observatory has vastly expanded the number of detected FRBs. In fact, according to research led by the National Astronomical Observatories of the Chinese Academy of Sciences (NAO/CAS), the observatory detected a total of 1,652 independent bursts from a single source in 47 days.

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What Are Your Options When you’ve Only Got Hours or Days to Prevent an Asteroid Impact?

Mining asteroids might be necessary for humanity to expand into the Solar System. But what effect would asteroid mining have on the world's economy? Credit: ESA.

Imagine a scenario where we detect an asteroid heading straight for Earth. Imagine that it will arrive in a couple of days, or worse, only a few hours. What could be done to stop it?

It might be possible to protect ourselves and the planet on such short notice. But we’d have to test and build the right infrastructure to do it.

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What’s Causing the Mysterious Radio Waves Coming From the Center of the Milky Way?

An artist's impression of ASKAP J173608.2-321635, the mysterious radio source at the center of the Milky Way. Image Credit: Sebastian Zentilomo.

The center of the Milky Way is a mysterious place. Astronomers think there’s a supermassive black hole there, though it could be dark matter instead. The region is densely packed with stars, dominated by red giants. And because of all the dust between Earth and the galactic center, we can’t see anything with visible light, ultraviolet light, or low-energy x-rays.

But we can detect radio waves, and there are some unexplained ones coming from the center of the galaxy, and adding to the mystery.

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Europa has Water in its Atmosphere

Observations by the NASA/ESA Hubble Space Telescope recently revealed water vapour in the atmosphere of Ganymede, one of Jupiter’s moons. A new analysis of archival images and spectra has now revealed that water vapour is also present in the atmosphere of Jupter’s icy moon Europa. The analysis found that a water vapour atmosphere is present only on one hemisphere of the moon. This result advances our understanding of the atmospheric structure of icy moons, and helps lay the groundwork for upcoming science missions which will explore Jupiter’s icy moons.

Since the Voyager probes passed through the Jupiter system in 1979, scientists have been intrigued and mystified by its moon Europa. Once the images these probes acquired of the moon’s icy surface returned to Earth, scientists began to speculate about the possibility of a subsurface ocean. Since then, the detection of plume activity and other lines of evidence have bolstered this theory and fed speculation that there could be life beneath Europa’s icy surface.

According to new research, another critical piece of evidence of Europa’s watery nature has at least been confirmed. Using a similar technique that confirmed the presence of atmospheric water vapor in Jupiter’s moon Ganymede, Lorenz Roth of the KTH Royal Institute of Technology confirmed that Europa has water vapor in its atmosphere. This discovery could lead to a greater understanding of Europa’s atmosphere and surface environment, informing missions headed there in the near future.

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A Magnetic Tunnel Surrounds the Earth

The sky as it would appear in radio polarized waves. The Van-Gogh-like lines show magnetic field orientation. Image Credit: Pixabay/wal_172619, with edits by J. West.

What if our eyes could see radio waves?

If we could, we might be able to look up into the sky and see a tunnel of rope-like filaments made of radio waves. The structure would be about 1,000 light-years long and would be about 350 light-years away.

This tunnel explains two of the brightest radio features in the sky.

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This’ll be us… in 5 Billion Years

Scientists have long known the fate of our solar system – and likely the fate of Earth itself.   In a few billion years, the Sun will run out of fusion fuel and expand to a “red giant” phase, likely swallowing everything in the solar system up to the orbit of Mars.  But, some of the planets past that point could survive, like Jupiter and Saturn.  Now, scientists have used the Keck Observatory to see a system that looks like what ours will after the Sun’s red giant phase for the very first time.

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A Spacecraft Could use Gravity to Prevent a Dangerous Asteroid Impact

The idea of avoiding asteroid impacts has featured prominently in the public’s mind for decades – especially since the release of Deep Impact and Armageddon.  But is using a nuclear explosion the best way to deal with potentially hazardous space rocks?  Decidedly not.  If given enough time, there is a much more effective (and safer) way to dealing with any object on a collision course with Earth – a gravity tractor.  Now, Dr. Yohannes Ketema from the University of Minnesota has developed a flight pattern that makes this simplest of all asteroid defense mechanisms that much more effective.

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Did Titan Give Saturn its Tilt?

Giant planets like Saturn don’t just tilt over all by themselves: something has to knock them over, or tug on them gravitationally, to push them off axis. Scientists expect that when new planets are born, they form with almost no tilt at all, lining up like spinning tops, with their equators level to the orbital plane in which they circle around their sun.

But no planet in our solar system is perfectly level. Jupiter is the closest, boasting an obliquity (tilt) of just 3.12 degrees. Earth’s obliquity is much more substantive at 23.45 degrees, causing us to experience an annual cycle of seasons as our homeworld wobbles on its axis. Saturn’s tilt is more extreme yet, with an obliquity of 26.73 degrees (though it’s nowhere near as extreme as Uranus, which is practically sideways, spinning at a 97.86-degree angle to its orbital plane).

We can learn a lot from these obliquities.

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