A Stellar Stream of Stars, Stolen from Another Galaxy

The all-sky view that the Gaia survey would have of a simulated Milky-Way-like galaxy. [Credit: Sanderson et al. The Astrophysical Journal, January 6, 2020, DOI: 10.3847/1538-4365/ab5b9d]

Modern professional astronomers aren’t much like astronomers of old. They don’t spend every suitable evening with their eyes glued to a telescope’s eyepiece. You might be more likely to find them in front of a super-computer, working with AI and deep learning methods.

One group of researchers employed those methods to find a whole new collection of stars in the Milky Way; a group of stars which weren’t born here.

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Instead of Going Straight to Mars, Astronauts Should Make a Slingshot Past Venus First

A computer generated view of Mars, with an area including Gale Crater beginning to catch morning light. Image Credit: NASA/JPL-Caltech

Every 26 months, the orbits of both Earth and Mars conspire to make travel between the two planets shorter. Launching in one of these windows means the travel time can be reduced to only six months. Our robotic missions to the Martian surface, and missions that place satellites in Martian orbit, launch during these windows.

But are there other alternatives to this mission architecture?

One group of researchers says that crewed missions to Mars shouldn’t go directly to their destination; they should slingshot past Venus first.

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How Would We Do Surgery in Space?

Virtually rendered cutaway view of a postulated traumapod surgical module. Multiple layers of thermal and radiation shielding are visible. A four?armed surgical robot is situated within the module. The patient is tethered to the operating table, while the assistant, using a touchscreen console, is tethered to the module structure via a movable chair. Illustration by T. Trapp (https://www.planvis.co.uk) CC BY-SA 4.0

Any mission to Mars requires deeper planning than missions to the ISS or the Moon. Based purely on the length of the mission, contingencies branch outwards in complex logistical pathways. What if there’s an accident? What if someone’s appendix bursts?

And what if surgery is needed?

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1 in 10 Red Giants are Covered in Spots, and They Rotate Surprisingly Quickly

Artist's impression of a red giant star. If the star is in a binary pair, what happens to its sibling? Credit:NASA/ Walt Feimer

Sunspots are common on our Sun. These darker patches are cooler than their surroundings, and they’re caused by spikes in magnetic flux that inhibit convection. Without convection, those areas cool and darken.

Lots of other stars have sunspots, too. But Red Giants (RGs) don’t. Or so astronomers thought.

A new study shows that some RGs do have spots, and that they rotate faster than thought.

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Astronomers Have Mapped Out an Enormous Structure in the Universe Called the South Pole Wall

A projection of the South Pole Wall in celestial coordinates. Image Credit: Pomarède et al, 2020.

Galaxies aren’t spread evenly throughout space. They exist in groups, clusters, and superclusters. Our own Milky Way galaxy exists in an impossibly vast structure called the Laniakea supercluster. Laniakea was defined in 2014, and it contains over 100,000 galaxies.

Now a team of astronomers have discovered another immense feature beyond Laniakea, called the South Pole Wall.

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Parker Solar Probe Gives a Unique Perspective on Comet NEOWISE

This unprocessed image from NASA’s Parker Solar Probe shows comet NEOWISE on July 5, 2020, shortly after its closest approach to the Sun. Credits: NASA/Johns Hopkins APL/Naval Research Lab/Parker Solar Probe/Brendan Gallagher

Comet watchers have enjoying the newly-discovered NEOWISE comet since it was first spotted in March 2020. Now that it’s visible with the naked eye, in dark sky conditions, all kinds of Earthly observers are checking the visitor out.

But NASA’s Parker Solar Probe has another view of the comet, one denied to Earth-bound observers.

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Watch the Incredible Plume of Dust from Africa Cross the Entire Atlantic Ocean

The Saharan dust plume over the Atlantic Ocean. Image Credit: contains modified Copernicus Sentinel data (2020), processed by ESA, CC BY-SA 3.0 IGO

Dust plumes are a natural phenomena, part of Earth’s nutrient cycle. They occur when high-velocity winds pick up tiny dry particles from the Earth’s surface and carry them long distances. Every summer, dust plumes from Africa’s Sahara desert travel across the Atlantic Ocean.

They’re usually not this big, and they often sink into the ocean. But this one’s coming right to America.

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This Giant Iceberg Has Been Sailing the Southern Seas for Three Years Now

The iceberg A-68A floating in open waters about 1050 km from its birthplace. It's been floating for three years. Image Credit: contains modified Copernicus Sentinel data (2020), processed by ESA, CC BY-SA 3.0 IGO

An iceberg that calved off of from a larger ice formation has spent three years floating on the ocean near Antarctica. The iceberg broke off of the Larsen Ice Shelf in mid-July 2017. It’s been battered and split up into three pieces, but it’s still going.

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Even If We Cut Greenhouse Gas Emissions Tomorrow, it Would Take Decades for the Earth to Start Cooling Again

Our beautiful, precious, life-supporting Earth as seen on July 6, 2015 from a distance of one million miles by a NASA scientific camera aboard the Deep Space Climate Observatory spacecraft. Credits: NASA
Our beautiful, precious, life-supporting Earth as seen on July 6, 2015 from a distance of one million miles by a NASA scientific camera aboard the Deep Space Climate Observatory spacecraft. Credits: NASA

If—or hopefully when—we cut our Greenhouse Gas (GHG) emissions, we won’t notice much difference in the climate. The Earth’s natural systems take time to absorb carbon from the atmosphere. We may have to wait decades for the temperatures to drop.

Of course, that doesn’t mean we shouldn’t do it. It’s just that we have to temper our expectations a little.

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If Planet 9 is a Primordial Black Hole, We Might Be Able to See Flares When it Consumes Comets

Artist's conception of accretion flares resulting from the encounter of an Oort-cloud comet and a hypothesized black hole in the outer solar system. Credit: M. Weiss

A comet-eating black hole the size of a planet? It’s possible. And if there’s one out there in the distant Solar System, a pair of researchers think they know how to find it.

If they do, we might finally put the Planet 9 issue to rest.

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