Astronomy is about to get a whole lot more exciting
About six months have passed since the most powerful space telescope in history bid farewell to Earth and lifted off in darkness. Meanwhile, the James Webb Space Telescope has deployed its gold-coated mirrors, turned on its instruments, and got used to operating 1 million miles from Earth. He’s had a good look around and he’s almost ready to show us what he’s found: NASA is expected to release the first batch of color images and observations of Webb early next week.
Astronomers all over the world are – how can I put this very seriously and scientifically? – absolutely excited about it. Just bouncing off the walls. They’re amplified even more now that NASA has released the list of cosmic objects that will be revealed on Tuesday. Scientists know that Webb is about to become the star of astronomy. The observatory, a joint project of NASA and the European and Canadian space agencies, is 100 times more powerful than the Hubble Space Telescope. It can study celestial objects in ways Hubble can’t, and look deeper into the cosmos too – at some of the oldest stars and galaxies, which ignited shortly after the Big Bang. It’s not hyperbole to say that Webb’s observations will provide an entirely new sense of the universe and how it all happened.
For astronomers, being here at the dawn of a bold new understanding is like trying to fall asleep on Christmas Eve. (They are certainly less stressed than they were on the real night before Christmas, 2021, in the hours leading up to Webb’s launch into space on December 25.)
Next week’s lineup includes an assortment of topics meant to demonstrate Webb’s lineup as a versatile space telescope capable of showing us the universe in infrared, a wavelength invisible to our eyes.
There are a pair of nebulae, radiant regions in interstellar space. The Carina Nebula is a swirling cloud of gas and dust located about 7,600 light-years from Earth and home to radiant stars several times more massive than our sun. Hubble’s views of this object are already breathtaking. The Southern Ring Nebula is an ever-expanding cloud of gas around a dying star, located about 2,000 light-years away. Nebulae are known to be photogenic environments, so these shots will be dazzling.
Then there’s galactic goodness. The Stephan Quintet, named after the 19th-century French astronomer who discovered them, is a cluster of galaxies about 290 million light-years away. Four of the five galaxies are locked in a sort of dance together, their shapes distorted by each other’s gravitational fields. Webb will also show us a cluster of galaxies known as SMACS 0723, where galaxies distort and amplify light emanating from other objects behind them, a cosmic oddity that allows telescopes to spot very distant and faint galaxies farther away. It’s the kind of job Webb was designed to do best. Hubble’s famous “deep field” has cataloged thousands of galaxies; Future Webb deep fields will reveal 1 million.
And then there’s WASP-96b, a giant exoplanet orbiting a star nearly 1,150 light-years away. Webb won’t show us an image of the planet, but rather a “spectrum” – visual data that reveals what kinds of molecules are floating around in the atmosphere of this alien world. Webb isn’t designed to directly photograph planets beyond our solar system in fine detail, but it can examine their cloud tops for chemical signatures we know are associated with life.
The targets for Webb’s big debut were chosen by a small group made up of representatives from all three space agencies. Few people in the astronomical community seem to know exactly who was in it, or, if they do, they won’t tell; Heidi Hammel, an astronomer at the Association of Universities for Research in Astronomy, described the group to me as “the sanctuary within.” All the work was done very secretly, which only heightened the anticipation ahead of the official release.
For astronomers, the broadcast of the first images of Webb marks the real start of his scientific operations. NASA released a few practice images over the past six months, mostly to show how well Webb’s science instruments were working, and astronomers pored over these little glimpses, which captured bright hints of distant galaxies. “People were producing catalogs of galaxies just from a JPEG,” Sarah Kendrew, a European Space Agency astronomer who works at the Space Science Telescope Institute in Maryland, which operates Webb, told me. “People were really digging, going, What are the contact details? What are these galaxies in the background?”
Soon the data will be really to flow. Webb’s first year of observations is already planned, filled with research proposals from scientists around the world to study targets as familiar as the planets of our solar system and objects as mysterious as black holes at the centers of distant galaxies. “The mood is definitely changing from Maybe one day we will have data at Whoa, buckle up, the ride’s about to beginsaid Hammel, who has worked on the Webb project for more than two decades.
But astronomers will certainly take a moment to bask in the wonder of these first images. Pierre Ferruit, the European Space Agency’s Webb project scientist, told me today that he saw some of the images yesterday, but could not divulge any details. He just smiled widely. “They were pretty fantastic,” Ferruit said. “It’s worth the wait.” So watch this space, literally.