The NASA/ESA Hubble Space Telescope observed Saturn on June 6. NASA, ESA, A. Simon (GSFC) and the OPAL Team, and J. DePasquale (STScI) hide caption

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A bit of lapis lazuli — a rich blue pigment — is trapped within a central tooth's dental tartar on this lower jaw of a European woman who died sometime between A.D. 997 and 1162. Christina Warinner/Science Advances hide caption
A Blue Clue In Medieval Teeth May Bespeak A Woman's Artistry Circa A.D. 1000
Biological Cartographers Seek To Map The Trillions Of Cells In The Human Body
A Look At The Methodical Plan China Has Laid Out For Space Exploration
This enhanced color image of Ultima Thule was taken at a distance of 85,000 miles and highlights its reddish surface. The image on the right has a far higher spatial resolution. NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute hide caption
An artist's impression of NASA's New Horizons spacecraft encountering Ultima Thule, a Kuiper Belt object that orbits 1 billion miles (1.6 billion kilometers) beyond Pluto, on Jan. 1, 2019. JPL/NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute/Steve Gribben hide caption
Drosophila melanogaster, the common fruit fly, is a mainstay of genetics and biology labs. Courtesy of Marcus Stensmyr hide caption
Neil deGrasse Tyson said of the allegations: "But what happens when it's just one person's word against another's, and the stories don't agree? That's when people tend to pass judgment on who is more credible than whom." Santiago Felipe/Getty Images hide caption
Forged in 1879 and sanctioned by the General Conference on Weights and Measures at its first meeting, Le Grand K, the international prototype of the kilogram, has been kept under lock and key in a vault outside Paris. BIPM hide caption
Say Au Revoir To That Hunk Of Metal In France That Has Defined The Kilogram
Arrangement of colored oviraptor-like eggs in an oviraptorid nest arrangement Jasmina Wiemann/Yale University hide caption
A new analysis of what were initially thought to be microbial fossils in Greenland suggests they might instead just be mineral structures created when ancient tectonic forces squeezed stone. While most of the structures point in one direction, the red arrow shows that some point in the other direction. Courtesy of Abigail Allwood hide caption
Geologists Question 'Evidence Of Ancient Life' In 3.7 Billion-Year-Old Rocks
Smoke rises as first-stage boosters separate from a Soyuz rocket with a Soyuz MS-10 spacecraft carrying a NASA astronaut and a Russian cosmonaut. The mission was aborted shortly after launch, and the pair returned to Earth safely in an emergency landing. Dmitri Lovetsky/AP hide caption
(Top row, from left) Titan, Earth's moon, Europa and Enceladus. (Bottom row, from left) Callisto, Charon, Ariel and lo. Courtesty of NASA hide caption
Biochemical engineer Frances Arnold receives the Millennium Technology Prize 2016 during the awards ceremony in Helsinki, Finland. Arnold, an American, shares this year's Nobel Prize in Chemistry with two others, another American, George P. Smith and the U.K.'s Sir Gregory P Winter. Heikki Saukkomaa/Lehtikuva via AP hide caption