Mark Megahan
The science of Astronomy has already been reshaped by the James Webb Space Telescope and it’s only been on the job for two weeks. Everybody knew that our newest special infrared observer was capable of some really great things and NASA’s first official images prove it. Mere days after Webb delivered the initial data, “astronomers reported exciting new discoveries about galaxies, stars, exoplanets and even Jupiter.”
Astronomy on the edge
The debut “deepfield” image was the first to arrive and Massimo Pascale had his Astronomy team ready and waiting for it to download. Directing things from the University of California, Berkeley, Pascale and 14 collaborators “divvied up tasks.” All at once, they had “thousands of galaxies” to examine. All from a single “pinprick-size portion of the sky.”
As they scrambled to beat a publishing deadline, they “worked nonstop. It was like an escape room.” Three days later they hit the upload button and their paper came in second. The first team logged theirs only 13 seconds sooner. Disappointing but it “was pretty funny,” said Pascale.
Guillaume Mahler in the Astronomy Department at Durham University in the United Kingdom and his colleagues are “glad they rushed their version” of the image analysis. “There was just a sheer pleasure of being able to take this amazing data and publish it,” Mahler said. “If we can do it fast, why should we wait?” The real winner from the “healthy competition” is the public. Some of the new data reveals a “newfound galaxy dubbed GLASS-z13.”
It looks like a red blob but that’s because the object “is so far away that we see it as it appeared 300 million years after the Big Bang” It hadn’t had time to get started doing much yet. That splotch now “holds the record for the earliest known galaxy.” Even so, “that record is not expected to last long.” Both teams noted the new galaxy in their findings.
Deeper looks at the deepfield image reveal to Astronomers one labeled SMACS 0723. That cluster “is so heavy that it bends the light of more distant objects, bringing them into view. Pascale and Mahler found up to 16 remote galaxies that have been magnified in the image; their exact ages aren’t yet known.” Another smudge of light that Webb imaged dates to 700 million years after the Big Bang.
The spectrograph shows “heavy elements, particularly oxygen, in the galaxy.” Everyone in the Astronomy department is hoping to prove that there is “an absence of heavy elements in even earlier galaxies — evidence that these galaxies contain only Population III stars, the hypothesized first stars in the universe, thought to have been monstrously huge and made entirely from hydrogen and helium.”
No heavy elements
Astronomy can be puzzling sometimes but astrophysicist Andy Bunker explains that they’re “looking for galaxies where we see no heavy elements. Theoretically they should exist. It depends whether they’re bright enough.”
Another image that has everyone excited is one which shows “ribbonlike channels of star formation in galaxy NGC 7496 that were previously shrouded in dust and therefore invisible.”
A team at the National Science Foundation’s NOIRLab in Arizona zeroed in on NGC 7496, “whose young star-forming regions have until now been shrouded in darkness.” Hubble wasn’t built to “penetrate the thick dust and gas that surrounds these regions.” Webb can.
Because it specialized in the infrared part of the astronomy spectrum, it can see light “that bounces off the dust, allowing the telescope to probe close to the moments when the stars switched on and nuclear fusion ignited in their cores.” According to Janice Lee, “the dust is actually lighting up.”
John Barentine, who does astronomy for the dark-sky conservation firm Dark Sky Consulting, “made a more serendipitous discovery in one of JWST’s first images. The telescope’s picture of the Southern Ring Nebula, 2,500 light-years from Earth, showed remarkable clarity. Off to the side, an intriguing galaxy viewed edge-on (a unique vantage point for studying the galaxy’s central bulge), previously misidentified as part of the nebula itself, poked into view.”
For bonus points, “the mysterious, red-hot glow of Jupiter’s upper atmosphere is visible in JWST’s 75-second exposure of the planet. Also visible are Jupiter’s thin ring and its icy moon Europa shining brightly on the left. A small atmospheric disturbance, visible on the planet’s bottom edge, is caused by an interaction with the volcanic moon Io.“
