From 2009 to late 2013, the European Space Agency's Planck spacecraft revolved around our planet while using its telescope to soak up relic radiation from the Big Bang known as the Cosmic Microwave Background, or CMB. Its goal, in effect, was to look back in time to just about 370,000 years after the Big Bang.
Now NASA's Jet Propulsion Lab (JPL), which worked closely with the ESA on the Planck mission, has released a captivating interactive map of the Milky Way using Planck's data. It combines multiple views of our galaxy, including mapping dust, carbon monoxide gas, magnetic fields and a type of radiation known as "free-free." This kind of radiation happens when "isolated electrons and protons careen past one another in a series of near collisions, slowing down but continuing on their own way," according to the JPL.
You can swoop through the map and set it to show different characteristics of the Milky Way on the Planck website here.
"The cosmic microwave background light is a traveler from far away and long ago," Charles Lawrence, the US project scientist for the mission at NASA's JPL, said in a statement. "When it arrives, it tells us about the whole history of our universe."
To study the CMB, Planck team members needed to remove the light from our galaxy, much of which is the same wavelength as the relic radiation. The team then used that removed light to create the new map. "Light generated from within our galaxy, the same light subtracted from the ancient signal, comes to life gloriously in the new image," the JPL says. "Gas, dust and magnetic field lines make up a frenzy of activity that shapes how stars form."
Not only was the space agency able to create the map thanks to the Planck mission, but by analyzing data sent back from the mission the team also discovered a few other things.
First, it was once believed that the Dark Ages of our universe -- a time before stars began winking into existence -- lasted for 300 million to 400 million years after the Big Bang. Looking at the Planck data, however, researchers now believe that the period of darkness lasted for about 550 million years.
Even more compelling was a revelation about dark energy, an as-yet-unproven force that scientists believe is responsible for the accelerating speed of the universe's expansion. "The Planck data also support the idea that the mysterious force known as dark energy is acting against gravity to push our universe apart at ever-increasing speeds," the JPL said.
The Planck team will continue analyzing the data, and it's expected that more insights about the origin and nature of our universe will be published next year. "The kind of questions we ask now we never would have thought possible to even ask decades ago, long before Planck," said James Bartlett, a US Planck team member from JPL.
If you've got a few extra minutes, this short video is a great explanation of how Planck did its thing during its mission.