NASA just made a map of the entire sky that could tell us how the Universe began

NASA just made a map of the entire sky that could tell us how the Universe began

Save 30% on the shop price when you subscribe to BBC Sky at Night Magazine today!
An all-sky map produced by NASA's SPHEREx mission, showing wavelengths of light emitted by red clouds of a type of cosmic dust known as polycyclic aromatic hydrocarbons and bubbles of hydrogen gas (blue). Both of these materials are a common ingredient in the formation of stars and planets. Credit: NASA/JPL-Caltech
An all-sky map produced by NASA's SPHEREx mission, showing wavelengths of light emitted by red clouds of a type of cosmic dust known as polycyclic aromatic hydrocarbons and bubbles of hydrogen gas (blue). Both of these materials are a common ingredient in the formation of stars and planets. Credit: NASA/JPL-Caltech

Iain Todd

A NASA space telescope has completed its first infrared map of the entire sky, as seen from Earth, in 102 different wavelengths of light.

The maps, produced by the SPHEREx space observatory, reveal the secrets of the Universe not visible to the human eye.

More mind-blowing science

Origin of the Universe. Credit: Mark Garlick / Science Photo Library / Getty Images
Credit: Mark Garlick / Science Photo Library / Getty Images

It's thought that the observations could help scientists unlock some of the biggest mysteries in the Universe, including how a dramatic event that occurred immediately after the Big Bang shaped our entire cosmos.

It could also help reveal how galaxies have evolved over 13.8 billion years since the Big Bang, and the distribution of the building blocks of life across our own Galaxy.

An eye on the sky

"SPHEREx is a mid-sized astrophysics mission delivering big science," says Dave Gallagher, director at NASA's Jet Propulsion Laboratory.

"It’s a phenomenal example of how we turn bold ideas into reality, and in doing so, unlock enormous potential for discovery."

SPHEREx (Spectro-Photometer for the History of the Universe, Epoch of Reionization, and Ices Explorer) circles our planet 14.5 times a day, travelling north to south over Earth's poles.

And each day it captures 3,600 images along one circular strip of the sky.

An all-sky map produced by NASA's SPHEREx mission, showing wavelengths of light emitted by red clouds of a type of cosmic dust known as polycyclic aromatic hydrocarbons and bubbles of hydrogen gas (blue). Both of these materials are a common ingredient in the formation of stars and planets. Credit: NASA/JPL-Caltech
An all-sky map produced by NASA's SPHEREx mission, showing wavelengths of light emitted by red clouds of a type of cosmic dust known as polycyclic aromatic hydrocarbons and bubbles of hydrogen gas (blue). Both of these materials are a common ingredient in the formation of stars and planets. Credit: NASA/JPL-Caltech

Because SPHEREx moves with Earth around the Sun, its field of view shifts.

That means that, after six months of observations, SPHEREx has peered into deep space in every direction, giving scientists a 360° view of the whole sky.

The spacecraft launched in March 2025, began mapping the sky in May and completed its first all-sky mosaic in December 2025.

It's set to complete three more all-sky scans during its two-year primary mission.

Scientists say merging those maps will increase the sensitivity of its measurements. And NASA is making the whole dataset available to both scientists and the public.

An all-sky map produced by NASA's SPHEREx mission, showing wavelengths of light emitted by millions of stars and galaxies. Credit: NASA/JPL-Caltech
An all-sky map produced by NASA's SPHEREx mission, showing wavelengths of light emitted by millions of stars and galaxies. Credit: NASA/JPL-Caltech

SPHEREx and the secrets of the Universe

SPHEREx observes the Universe in 102 different colours, or wavelengths of light, which are invisible to the human eye.

That means it enables scientists to see things they would otherwise not be able to see.

This gives them information about galaxies, stars, planet-forming regions and other cosmic phenomena.

Dense clouds of dust in star-forming regions across the galaxy are too thick for us to see through with the naked eye, but observing in different wavelengths of light enables scientists to peer deep inside them.

Scientists say SPHEREx could help them uncover the mystery of a dramatic, cosmic event that happened in the first billionth of a trillionth of a trillionth of a second after the Big Bang, and how that influenced the distribution of hundreds of millions of galaxies in our Universe.

And scientists will use SPHEREx's data to discover how galaxies formed and changed over the 13.8 billion years since the Big Bang.

The data could also reveal how prevalent life is in our Galaxy.

SPHEREx has even given scientists a unique view of interstellar comet 3I/ATLAS. Credit: NASA/SPHEREx
SPHEREx has even given scientists a unique view of interstellar comet 3I/ATLAS. Credit: NASA/SPHEREx

"It’s incredible how much information SPHEREx has collected in just six months – information that will be especially valuable when used alongside our other missions’ data to better understand our Universe," says Shawn Domagal-Goldman, director of the Astrophysics Division at NASA Headquarters in Washington.

"We essentially have 102 new maps of the entire sky, each one in a different wavelength and containing unique information about the objects it sees.

"I think every astronomer is going to find something of value here, as NASA’s missions enable the world to answer fundamental questions about how the Universe got its start, and how it changed to eventually create a home for us in it."

Author avatar

Iain Todd

Science journalist

Iain Todd is BBC Sky at Night Magazine's Content Editor. He fell in love with the night sky when he caught his first glimpse of Orion, aged 10.
This website is owned and published by Our Media Ltd. www.ourmedia.co.uk
© Our Media 2025