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Dark Matter Core Defies Explanation NASA ID: GSFC_20171208_Archive_e001774 NASA image release March 2, 2012 This composite image shows the distribution of dark matter, galaxies, and hot gas in the core of the merging galaxy cluster Abell 520, formed from a violent collision of massive galaxy clusters. The natural-color image of the galaxies was taken with NASA's Hubble Space Telescope and with the Canada-France-Hawaii Telescope in Hawaii. Superimposed on the image are "false-colored" maps showing the concentration of starlight, hot gas, and dark matter in the cluster. Starlight from galaxies, derived from observations by the Canada-France-Hawaii Telescope, is colored orange. The green-tinted regions show hot gas, as detected by NASA's Chandra X-ray Observatory. The gas is evidence that a collision took place. The blue-colored areas pinpoint the location of most of the mass in the cluster, which is dominated by dark matter. Dark matter is an invisible substance that makes up most of the universe's mass. The dark-matter map was derived from the Hubble Wide Field Planetary Camera 2 observations, by detecting how light from distant objects is distorted by the cluster galaxies, an effect called gravitational lensing. The blend of blue and green in the center of the image reveals that a clump of dark matter resides near most of the hot gas, where very few galaxies are found. This finding confirms previous observations of a dark-matter core in the cluster. The result could present a challenge to basic theories of dark matter, which predict that galaxies should be anchored to dark matter, even during the shock of a collision. Abell 520 resides 2.4 billion light-years away. To read more go to: www.nasa.gov/mission_pages/hubble/science/dark-matter-cor... Credit: NASA, ESA, CFHT, CXO, M.J. Jee (University of California, Davis), and A. Mahdavi (San Francisco State University)

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Arc Jet Complex Providing ground-based hyperthermal environments in support of the Nation?s Research & Development activities in Thermal Protection Materials, Vehicle Structures, Aerothermodynamics, and Hypersonic Entry. https://www.facebook.com/nasaames/videos/10154330812546394/ Benefit Innovative thermal protection materials and systems will be required to support NASA Exploration. Project missions, in particular crewed Moon or Mars return missions, will involve high velocity aerocapture or direct entry at Earth. These high stress missions will induce heating environments too severe for existing reusable Thermal Protection Systems (TPS). Qualifying a new TPS material for a crewed mission requires extensive testing to explore the limits of material performance, to validate reliability and repeatability of performance, to investigate the effects of material damage, and to develop a full database of material properties. Arc plasma facilities, operated by the Thermophysics Facilities Branch at NASA Ames, are critical to such a process, and to any other TPS developments required for Exploration missions, by providing the only ground-based simulation of flight entry conditions.

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Comet C/2024 E1 Taken by Ian Griffin on February 5, 2026 @ Middlemarch, New Zealand Details: A lovely comet is gracing the southern sky. This evening I managed to get a set of 26x90 second exposures of it before moonlight interfered. The comet is sweeping through the southern constellation of Grus, which contains many beautiful galaxies. Photographer's website: https://www.instagram.com/portobellopictures/

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