By Katrina Miller
Whether capturing spiral galaxies or stellar nurseries, Euclid is showing off our universe’s good side.
Last Tuesday, the European Space Agency shared the first images from the robotic telescope in space — five ethereal views of our cosmos.
Launched in July, Euclid is on a quest to map one-third of the extragalactic sky and to reveal how the mysterious influences of dark matter and dark energy have shaped the structure of the universe. The new images are just a taste of what scientists expect the space telescope to achieve.
“I’m just overwhelmed by the sheer scale of the data,” said Michael Seiffert, a cosmologist at NASA’s Jet Propulsion Laboratory who is a member of the Euclid mission. “The ability to have really sharp images cover a wide field at the same time is just really astounding.”
Perhaps most striking is a shot of the Horsehead Nebula, a star factory 1,375 light-years from Earth with a distinct equine-shaped cloud. The image shows reddish brown gas and dust churning with baby stars, young Jupiter-like worlds and rogue planets detached from a host star. In the lower left corner, massive infant stars cast the interstellar clouds of another nebula, NGC 2023, in a soft lavender glow.
Scientists also released a spectacular new view of the Perseus Cluster, an aggregation of galaxies 240 million light-years away. Most of the colored specks are not stars, Seiffert said, but galaxies — some so faint they have never before been seen. Free-floating stars, stripped from their galaxies and drifting in the spaces between, may also be nestled in the cluster.
The Euclid team also shared close-ups of galaxies: a wispy white spiral, IC 342, similar to our Milky Way, and an irregular dwarf galaxy, NGC 6822, among a dense field of stars. The final image shows the globular cluster NGC 6397, a collection of stars orbiting in the disc of our own galaxy.
Whereas NASA’s James Webb Space Telescope zooms in on one part of the sky at a time, Euclid excels at imaging wide, but still detailed, swaths of the universe. That’s perfect for “when you want to look for a needle in a haystack,” Seiffert said, including objects like free-floating worlds.
With the data Euclid sends home, researchers can learn about how the web of dark matter cementing our universe together influences the shapes and motions of visible objects in space. The telescope’s detailed resolution is also expected to help scientists map the distribution of galaxies across cosmic time, aiding in understanding dark energy, the inexplicable force pulling the universe apart.
The mission team is wrapping up final checks and calibrations of Euclid’s instruments, which include a 600-megapixel camera for imaging and a near-infrared spectrometer and photometer that will record the light from galaxies in wavelengths that are not visible to infer their distance. Over the summer, scientists worked around the clock to fix a faulty navigation sensor that made Euclid create images of winding star trails as the telescope tried to capture a piece of sky.
Scientific observations are scheduled to begin early next year. In 2025, scientists plan to release Euclid’s first maps of the universe, which will include more sky area than in all of the data collected so far by NASA’s Hubble Space Telescope, Seiffert said.
And the team anticipates that Euclid will chart the sky over the next six years, assembling a trove of 12 billion sources for astronomers to dig into and discover.
“The data that came out represents less than a day’s worth of observing,” Seiffert said about Euclid’s first images. “We’re just going to be drowning in data for years and years to come.”