One question keeps bouncing around my mind as I look at this image from the new James Webb Space Telescope: How is this real? I have followed the story of Webb for years, chronicling the ups and downs and controversies the mission has experienced on its way to becoming a real, functioning telescope. I’ve talked with many dozens of scientists and engineers about how the observatory works and the kind of high-resolution images it is designed to produce. I was there, three miles from the launchpad, when this thing blasted off of the planet last year. This is all very real. And yet I still can’t believe what I’m seeing in this picture of the Carina Nebula, a luminous region about 7,600 light-years away.
The nebula is home to countless young stars, glittering like gemstones. These stars are so full of energy that they whip cosmic gas around, shaping it into peaks and valleys at the nebula’s edge. Beyond that veil of dust are still more stars shimmering in the darkness.
There’s just so much in this little corner of the universe, and so much more than what we usually imagine when we think of the cosmos that lies far beyond our little planet. Consider the language that we often use to describe what lies beyond our atmosphere: the expanse, empty space, a void. This image completely upends that perception.
Instead of highlighting the vastness of space, the Carina Nebula image reveals its richness. We see a scene bursting with density and texture. At first glance, the edge of the nebula resembles a rocky mountaintop, something hard and scalable. Look closer, and the nebula seems soft and smoky. You can imagine walking through it and feeling the powdery particles brush against your skin. When I saw this picture today, I felt a strange pang of indignation, the kind of feeling you get when you realize you’ve been lied to, or at least not told the whole truth. All of this has been here? The whole time?
In a word, yes. The stuff in this image “was always out there,” Jane Rigby, a NASA astrophysicist and the project scientist for Webb operations, told reporters at a NASA press conference today. “We just had to build a telescope to go see what was there.”
The view of the Carina Nebula is one of several images that NASA has released to the public this week to mark the beginning of Webb’s science operations. The new observatory will spend the next 20 years scanning the universe, collecting untold amounts of data that will help astronomers study everything between Mars and the farthest reaches of the known universe. Webb sees the universe in infrared, the optimal wavelength for telescopes trying to see through cosmic dust and catch the light from the most distant stars and galaxies. The Webb telescope was designed to spot celestial objects that are about 100 times fainter than the ones that NASA’s other famous space telescope, Hubble, can detect. (Hubble, in case you’re wondering, is still out there and ticking, capturing the cosmos in mostly visible and ultraviolet wavelengths—still beautiful, but simply not as powerful.)
Infrared is invisible to us, which means that Webb’s sparkliest pictures, including the Carina shot, have been processed and filled in with color. Scientists pore over every pixel, measuring the incoming light and the ways it has been stretched on its way across the universe. We here on Earth perceive visible light in longer wavelengths as red, so the longest wavelengths of infrared light in a Webb image are rendered in red. Shorter wavelengths look blue to us, so shorter wavelengths in infrared are coded blue. The other colors of the rainbow stand in for medium wavelengths. Think of it like translating one language into another, Klaus Pontoppidan, a Webb project scientist, said in today’s press conference. “Infrared colors are just as real as visible colors,” he said. “If you had infrared eyes that were sensitive to this light, this may be what you would see.”
There is some artistic license involved, though. “You really are trying to show the different details and the processes that are happening in astronomical images, but at the end of the day, you want it to be very compelling,” Alyssa Pagan, a science-visuals developer at the Space Telescope Science Institute, which operates Webb, said during a NASA broadcast today. “You want it to be very beautiful because space is beautiful.”
Astronomers I spoke with in the days leading up to the big reveal weren’t surprised that NASA had picked the Carina Nebula as one of Webb’s first targets. The nebula is one of the largest and brightest in our night sky, and it is well-known for being photogenic. But when the image appeared on-screen at NASA’s Goddard Space Flight Center in Maryland, where hundreds had gathered for the big reveal, there were gasps, then silence. Earlier, the event had felt like a pep rally, with staff shaking gold pom-poms and leading the crowd in Webb-inspired cheers. Faced with Carina, the crowd in the auditorium seemed simply overwhelmed. It had certainly seen spectacular space pictures before; Hubble’s view of the Carina Nebula, for example, is lovely in its own right. But nothing quite like this, where every square inch is bursting with gas and dust and stars, all as real as the planet we’re on.