Space is Wildcat Country
The James Webb Space Telescope (Webb) will be the largest, most powerful telescope ever launched into space. It follows in the footsteps of the Hubble Space Telescope as the next great space science observatory, designed to answer outstanding questions about the Universe and to make breakthrough discoveries in all fields of astronomy.
Haunting Portrait: NASA’s Webb Reveals Dust, Structure in Pillars of Creation
This is not an ethereal landscape of time-forgotten tombs. Nor are these soot-tinged fingers reaching out. These pillars, flush with gas and dust, enshroud stars that are slowly forming over many millennia. NASA’s James Webb Space Telescope has snapped this eerie, extremely dusty view of the Pillars of Creation in mid-infrared light – showing us a new view of a familiar landscape.
Why does mid-infrared light set such a sombre, chilling mood in Webb’s Mid-Infrared Instrument (MIRI) image? Interstellar dust cloaks the scene. And while mid-infrared light specializes in detailing where dust is, the stars aren’t bright enough at these wavelengths to appear. Instead, these looming, leaden-hued pillars of gas and dust gleam at their edges, hinting at the activity within.
Thousands and thousands of stars have formed in this region. This is made plain when examining Webb’s recent Near-Infrared Camera (NIRCam) image. In MIRI’s view, the majority of the stars appear missing. Why? Many newly formed stars are no longer surrounded by enough dust to be detected in mid-infrared light. Instead, MIRI observes young stars that have not yet cast off their dusty “cloaks.” These are the crimson orbs toward the fringes of the pillars. In contrast, the blue stars that dot the scene are ageing, which means they have shed most of their layers of gas and dust.
Mid-infrared light excels at observing gas and dust in extreme detail. This is also unmistakable throughout the background. The densest areas of dust are the darkest shades of grey. The red region toward the top, which forms an uncanny V, like an owl with outstretched wings, is where the dust is diffuse and cooler. Notice that no background galaxies make an appearance – the interstellar medium in the densest part of the Milky Way’s disk is too swollen with gas and dust to allow their distant light to penetrate.
How vast is this landscape? Trace the topmost pillar, landing on the bright red star jutting out of its lower edge like a broomstick. This star and its dusty shroud are larger than the size of our entire solar system.
This scene was first captured by NASA’s Hubble Space Telescope in 1995 and revisited in 2014, but many other observatories, like NASA’s Spitzer Space Telescope, have also gazed deeply at the Pillars of Creation. With every observation, astronomers gain new information, and through their ongoing research build a deeper understanding of this star-forming region. Each wavelength of light and advanced instrument delivers far more precise counts of the gas, dust, and stars, which inform researchers’ models of how stars form. As a result of the new MIRI image, astronomers now have higher resolution data in mid-infrared light than ever before and will analyze its far more precise dust measurements to create a more complete three-dimensional landscape of this distant region.
The Pillars of Creation is set within the vast Eagle Nebula, which lies 6,500 light-years away.
Why satisfy yourself with one course when you can have a double helping?
The US space agency Nasa has issued a second image of the famous "Pillars of Creation" taken by the new super space telescope, James Webb. This week we get a rendering of the active star-forming region as seen by Webb's Mid-Infrared Instrument (MIRI).
Last week, it was the observatory's Near-Infrared Camera (NIRCam) that was highlighting this remarkable location some 6,500 light-years from Earth. The pillars lie at the heart of what astronomers refer to as Messier 16 (M16), or the Eagle Nebula.
They are the subject of intense study. Every great telescope is pointed in their direction to try to understand the physics and the chemistry in play as new stars are birthed in great clouds of gas and dust.
Webb, with its 6.5m-wide mirror and high-fidelity sensors, is the latest, biggest and best space observatory to take in the scene.
What's interesting about the new MIRI picture is the choice of wavelengths used to display the pillars.
Ordinarily, astronomers might filter the light to make the dusty columns go very largely translucent, so that their interior, nascent stars can be seen in greater detail. This is what the NIRCam image did: it emphasised the thousands of young blue stars that are present.
And MIRI is capable of taking this approach to another step. But on this occasion, the filtering has selected those wavelengths at which the dust itself actually glows. "Defying expectations that mid-infrared observations let you see through dust, this stunning image shows that they're also great for studying dust and complex molecules made to glow by the intense light of nearby hot stars," explained Prof Mark McCaughrean, the senior advisor for science at the European Space Agency.
Some of the complex chemistry this helps accentuate involves polycyclic aromatic hydrocarbons and PAHs. These are very carbon-rich compounds. You find them on burnt toast and in the exhaust of motor vehicles. PAHs produced by stars are thought to enrich the carbon content throughout the Universe.
MIRI was developed in a collaborative effort between scientists and engineers from 10 European countries, led by the UK, and Nasa's Jet Propulsion Laboratory.
Its co-principal investigator is Prof Gillian Wright.
"It's simply thrilling to see how well MIRI is performing. It's producing radically new science information - stuff we've never had before," the director of the UK Astronomy Technology Centre told BBC News.
"What we see in this new image is akin to the 'skin' of the pillars, if you like. You can see filamentary structures which are where the stars are starting to burn through the dust. And you can see regions that are dark - they're so dense and cold that they're not even lighting up for MIRI."
James Webb is a collaborative project of the US, European and Canadian space agencies. It was launched in December last year and is regarded as the successor to the Hubble Space Telescope.
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