Dec 19, 2017

Interstellar object has the heart of a comet

An artist's illustration of the first interstellar asteroid, `Oumuamua. Credit: European Southern Observatory

When a rocky interstellar object now known as 'Oumuamua was first detected in our solar system in October, it was thought to be an asteroid. Now, astronomers say it could be a comet whose core has withstood intense heat from the Sun thanks to a thick crust that insulated it, Science News reports.

Why it matters: Most objects that move between solar systems are thought to be comets so there was excitement that the presumed asteroid 'Oumuamua could help researchers to better understand how other solar systems formed. "Everybody's been assuming that this is just a lump of rock," study author Alan Fitzsimmons of Queen's University Belfast in Northern Ireland told Science News. "This may not be the case."

Comets v. asteroids: Unlike typically rocky asteroids, comets have an icy core that warms as they pass close to the Sun and releases gas and dust seen as a tail. 'Oumuamua traveled close to the Sun but had no tail which led researchers to first believe it was an asteroid.

The evidence: The spectrum of light reflected by 'Oumuamua's surface "similar to organically rich surfaces found in the outer Solar System," the authors wrote. "An internal icy composition cannot therefore be ruled out..." despite it passing close to the Sun and not producing a tail.

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The rematch of the century

Illustration: Eniola Odetunde/Axios

The weekend's biggest sporting event is Wilder-Fury II, which despite its name is not an action movie sequel starring Jean-Claude Van Damme but, rather, a boxing match starring arguably the two best heavyweights in the world.

The backdrop: In their first meeting in December 2018, Deontay Wilder and Tyson Fury put on a memorable show at Staples Center, with Fury surviving a brutal right hand in the 12th round to earn a split-decision draw.

Pro-Trump warrior takes the helm of U.S. intelligence

Richard Grenell in Berlin. Photo: Sean Gallup/Getty Images

By picking Ambassador Richard Grenell to be acting director of national intelligence, President Trump has slotted a pro-Trump warrior into the ultimate apolitical role.

What they're saying: James Clapper, the longest-serving DNI (2010-2017), tells Axios it's "very worrisome installing a partisan with no real intelligence experience in this position."

Coronavirus kills 2 Diamond Princess passengers as Israel confirms first case

Data: The Center for Systems Science and Engineering at Johns Hopkins, the CDC, and China's Health Ministry. U.S. numbers include Americans extracted from Princess Cruise ship.

Two elderly Diamond Princess passengers have been killed by the novel coronavirus — the first deaths confirmed among the more than 600 infected aboard the cruise ship — as Israel confirmed its first case among evacuees from the ship.

The big picture: COVID-19 has now killed more than 2,200 people and infected over 76,000 others, mostly in mainland China, where the National Health Commission announced 118 new deaths since Thursday.

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