NASA’s new SPHEREx space telescope will soon launch on its mission to answer some of humanity’s most fundamental questions around how life, and even the Universe itself, came to exist.
Over two years the spacecraft will map the entire sky in 102 different colours, or wavelengths, more than any all-sky mapper which has gone before it.
The spacecraft is expected to capture a staggering 450 million galaxies, as well as 100 million stars in our own Milky Way, helping astronomers to wind back the clock to a fraction of a second after the Big Bang.
SPHEREX (Spectro-Photometer for the History of the Universe, Epoch of Reionization and Ices Explorer) is a near-infrared telescope that will completely scan the sky once every six-months. The telescope uses a powerful technique called spectroscopy.
Starlight is imprinted with a light ‘fingerprint’ depending on what chemical elements it interacts with on its journey through the cosmos. By splitting starlight into a spectrum – similar to how visible light is split into a rainbow by a prism or raindrop – SPHEREx is able to reveal this fingerprint.
The NASA spacecraft can resolve 102 different colours, or wavelengths, giving astronomers an incredible level of detail they can use to pick apart the spectra to discover the chemistry of the stars and galaxies which emitted the light.
Revealing the origins of life, and the Universe with SPHEREx
Here in our own Galaxy, astronomers will be on the lookout for water and carbon based ‘organic’ molecules, both of which are basic ingredients for all life here on Earth.
Tracking their presence across the Milky Way will help reveal how these ingredients made their way to our planet, as well as revealing whether there might be other planetary systems out there with the right chemistry for life (at least as we know it).
NASA's SPHEREx telescope will also help reveal how the very Universe itself came to be. In the first billionth of a trillionth of a trillionth of a second after the Big Bang, almost 14 billion years ago, the Universe suddenly expanded to a trillion, trillion times its size.
It was during this event, called inflation, that the large-scale structure of our Universe was imprinted on the cosmos.
By mapping 450 million galaxies, SPHEREx will build one of the most detailed maps of this structure to date. As the light from some of these galaxies has taken as much as 10 billion years to reach us, this map also shows what the Universe looked like in the past. By analysing this celestial atlas, astronomers will be able to wind back the clock, gaining insight on how inflation helped to shape our Universe.
On top of all this, the NASA spacecraft will measure the cosmos’s background glow, created by the combined starlight of every galaxy. As this includes those too small or distant to be seen by themselves, this will give valuable insight into how many galaxies there truly are in the Universe.
SPHEREx set for launch
Currently, NASA are aiming to launch the SPHEREx telescope on 6 March, with a daily launch window for the spacecraft around 7:09 PM PST (03:10 AM GMT). The spacecraft will launch onboard a SpaceX Falcon 9 rocket from Space Launch Complex 4E at the Vandenberg Space Force Base in California, alongside another NASA mission to observe the Sun, called PUNCH.
SPHEREx will orbit Earth at an altitude of 650km (404 miles), where it will circle once every 98-minutes or so. Its path will take it over the poles, tracing out the line between Earth’s day and night sides, known as the terminator. This will keep the spacecraft in the same orientation to the Sun throughout the year, meaning it can more easily protect itself from the intense heat and light which would overwhelm SPHEREx’s sensors.
Once in place, the spacecraft will begin its two year long mission to create its multicoloured map of the heavens, and help reveal some of the cosmos' longest held secrets.
You will be able to watch the launch live over on NASA+.
