On March 4, 10:09 p.m. EST, a SpaceX Falcon 9 rocket will soon roar into the sky, carrying a compact NASA telescope with an extraordinary mission meant to answer some of the biggest questions in science: How did the universe begin? What are the building blocks of planets and life? And how has the cosmos evolved over billions of years?

To do so, this telescope, called SPHEREx, will map the entire sky to see the universe in 102 colors of light. Astronomers hope to detect the icy cradles of stars and the faint glow of all the light ever emitted by galaxies.

“It’s really mapping the sky in a novel way,” says Olivier Doré, a cosmologist at NASA’s Jet Propulsion Laboratory and a project scientist for SPHEREx. “It’s about opening up a new window on the universe.”

The most complete sky survey

SPHEREx’s can “see” the universe in 102 distinct “colors” of infrared light. Unlike other telescopes that focus on specific objects or narrow bands of light, SPHEREx will scan the entire sky, creating a massive, multidimensional map of the cosmos.

To understand how this cosmology powerhouse works, think of a color printer. Just as a printer combines layers of cyan, magenta, yellow, and black ink to create a full-color image, SPHEREx (short for Spectro-Photometer for the History of the Universe, Epoch of Reionization and Ices Explorer) uses just six special filters to break the sky’s light into 102 infrared wavelengths. Each wavelength reveals a different slice of cosmic history, from the icy clouds of our galaxy to the faint glow of the first galaxies born after the Big Bang. When you superimpose each of these 102 maps, you can then create a 3D map of the entire night sky and then use this chart to peer back in time — right to mere moments after the Big Bang itself.

“Each wavelength is kind of giving you a different slice through cosmic history,” says James Bock, a cosmologist at Caltech and the principal investigator of SPHEREx. “We are trying to probe pretty much all the whole cosmic history, all the way to the epoch of first star formation.”

SPHEREx has three primary science goals. The first is to map the icy ingredients of stars and planets. Throughout the Milky Way and neighboring galaxies, the telescope will search for water ice, frozen carbon dioxide, methanol, ammonia, and other compounds. These ices cling to interstellar dust grains and may represent the raw materials for planets—and possibly life. That’s because scientists have a hunch that interstellar ice is the source of water on Earth and elsewhere.

SPHEREx is poised to make some eight million observations of these ices, a staggering leap from the mere 200 measurements made before the James Webb Space Telescope, another powerful infrared telescope.

The second goal is to measure all the light ever emitted by every star, galaxy, and light-emitting object across the universe’s history. No big deal.

This faint, diffuse light, often called the “extragalactic background light,” is the sum of all the photons traveling across the cosmos since the first stars flickered on. By analyzing the redshift of this light—how its wavelengths stretch as the universe expands—SPHEREx will create a timeline of the cosmos’ history. The farther light travels, the more it redshifts. This means that the oldest light from the earliest galaxies, emitted billions of years ago, now exists only as infrared light. This could reveal how the first galaxies formed and how the universe’s light production has changed over billions of years.

“Even if you don’t see a star there, we’ll still see the light, the photons collectively emitted by all of the galaxies in the universe,” says Asantha Cooray, a cosmologist at the University of California, Irvine, and a member of the SPHEREx team.

The third and most ambitious goal is to probe cosmic inflation, the explosive expansion of the universe moments after the Big Bang. By mapping the positions of 450 million galaxies, SPHEREx will test theories about how inflation unfolded and what drove it.

“We are intellectually going back in time to the origin of the universe,” Doré says. “We can actually, pretty much with pen on paper, go from the distribution of galaxies on these larger scales, using physics we know, all the way to the physics of inflation.”

A Shared Ride to Space

SPHEREx won’t be traveling alone. Hitching a ride on the same rocket is PUNCH, a mission of four small satellites designed to study the sun’s outer atmosphere and the solar wind. While SPHEREx gazes into the depths of the universe, PUNCH will focus on the dynamics of our own star. Among its goals is helping scientists understand how the sun’s corona fuels the solar wind and affects space weather.

As the launch countdown begins, scientists around the world are waiting with bated breath. Tune in at NASA’s website or YouTube to watch the event live.

“The beauty of astronomy is: we know that every time we look at the sky in a different way, with a different instrument, from a different angle, we discover new things,” Doré says. SPHEREx, it seems, is poised to deliver discoveries beyond our wildest dreams.