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This is Defector, a new sports blog and media company. We made this place together, we own it together, we run it together. Without access, without favor, without discretion, and without interference.

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Defector

NYC: Come To Our WNBA Comedy Show On May 16

Ten Minute Quarters comedy show at 3:2 ratio

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Live Event

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Barry Petchesky

The NASA/ESA/CSA James Webb Space Telescope has captured the sharpest infrared images to date of one of the most distinctive objects in our skies, the Horsehead Nebula. These observations show a part of the iconic nebula in a whole new light, capturing its complexity with unprecedented spatial resolution. Webb’s new images show part of the sky in the constellation Orion (The Hunter), in the western side of the Orion B molecular cloud. Rising from turbulent waves of dust and gas is the Horsehead Nebula, otherwise known as Barnard 33, which resides roughly 1300 light-years away.  The nebula formed from a collapsing interstellar cloud of material, and glows because it is illuminated by a nearby hot star. The gas clouds surrounding the Horsehead have already dissipated, but the jutting pillar is made of thick clumps of material that is harder to erode. Astronomers estimate that the Horsehead has about five million years left before it too disintegrates. Webb’s new view focuses on the illuminated edge of the top of the nebula’s distinctive dust and gas structure. The Horsehead Nebula is a well-known photon-dominated region, or PDR. In such a region ultraviolet light from young, massive stars creates a mostly neutral, warm area of gas and dust between the fully ionised gas surrounding the massive stars and the clouds in which they are born. This ultraviolet radiation strongly influences the gas chemistry of these regions and acts as the most important source of heat.  These regions occur where interstellar gas is dense enough to remain neutral, but not dense enough to prevent the penetration of far-ultraviolet light from massive stars. The light emitted from such PDRs provides a unique tool to study the physical and chemical processes that drive the evolution of interstellar matter in our galaxy, and throughout the Universe from the early era of vigorous star formation to the present day. Owing to its proximity and its nearly edge-on geometry, the Horsehead Nebula is an ideal target for astronomers to study the physical structures of PDRs and the evolution of the chemical characteristics of the gas and dust within their respective environments, and the transition regions between them. It is considered one of the best objects in the sky to study how radiation interacts with interstellar matter. This image was captured with Webb’s NIRCam (Near-InfraRed Camera) instrument. [Image description: At the bottom of the image a small portion of the Horsehead Nebula is seen close-in, as a curved wall of thick, smoky gas and dust. Above the nebula various distant stars and galaxies can be seen up to the top of the image. One star is very bright and large, with six long diffraction spikes that cross the image. The background fades from a dark red colour above the nebula to black.]

Horsehead Nebula (NIRCam image)

Science

The Closer We Look The Smaller We Get

The graceful winding arms of the grand-design spiral galaxy M51 stretch across this image from the NASA/ESA/CSA James Webb Space Telescope. Unlike the menagerie of weird and wonderful spiral galaxies with ragged or disrupted spiral arms, grand-design spiral galaxies boast prominent, well-developed spiral arms like the ones showcased in this image. This galactic portrait was captured by Webb’s Mid-InfraRed Instrument (MIRI). In this image the reprocessed stellar light by dust grains and molecules in the medium of the galaxy illuminate a dramatic filamentary medium. Empty cavities and bright filaments alternate and give the impression of ripples propagating from the spiral arms. The yellow compact regions indicate the newly formed star clusters in the galaxy. M51 — also known as NGC 5194 — lies about 27 million light-years away from Earth in the constellation Canes Venatici, and is trapped in a tumultuous relationship with its near neighbour, the dwarf galaxy NGC 5195. The interaction between these two galaxies has made these galactic neighbours one of the better-studied galaxy pairs in the night sky. The gravitational influence of M51’s smaller companion is thought to be partially responsible for the stately nature of the galaxy’s prominent and distinct spiral arms. If you would like to learn more about this squabbling pair of galactic neighbours, you can explore earlier observations of M51 by the NASA/ESA Hubble Space Telescope here.  This Webb observation of M51 is one of a series of observations collectively titled Feedback in Emerging extrAgalactic Star clusTers, or FEAST. The FEAST observations were designed to shed light on the interplay between stellar feedback and star formation in environments outside of our own galaxy, the Milky Way. Stellar feedback is the term used to describe the outpouring of energy from stars into the environments which form them, and is a crucial process in determining the rates at which stars form. Understanding stellar feedback is vital to building accurate universal models of star formation. The aim of the FEAST observations is to discover and study stellar nurseries in galaxies beyond our own Milky Way. Before Webb became operative, other observatories such as the Atacama Large Millimetre Array in the Chilean desert and Hubble have given us a glimpse of star formation either at the onset (tracing the dense gas and dust clouds where stars will form) or after the stars have destroyed with their energy their natal gas and dust clouds. Webb is opening a new window into the early stages of star formation and stellar light, as well as the energy reprocessing of gas and dust. Scientists are seeing star clusters emerging from their natal cloud in galaxies beyond our local group for the first time. They will also be able to measure how long it takes for these stars to pollute with newly formed metals and to clean out the gas (these time scales are different from galaxy to galaxy). By studying these processes, we will better understand how the star formation cycle and metal enrichment are regulated within galaxies as well as what are the time scales for planets and brown dwarfs to form. Once dust and gas is removed from the newly formed stars, there is no material left to form planets. [Image Description: A large spiral galaxy takes up the entirety of the image. The core is mostly bright white, but there are also swirling, detailed structures that resemble water circling a drain. There is white and pale blue light that emanates from stars and dust at the core’s centre, but it is tightly limited to the core. The detailed rings feature bands of deep orange and cloudy grey, which are interspersed by darker empty regions throughout.]

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