(CNN) -- Mars is about to get its first thorough checkup since it formed billions of years ago, as NASA's InSight heads to the red planet after launching Saturday morning from Vandenberg Air Force Base in California
"Three ... two ... ... zero ... Lift off, of the Atlas V -- launching the first interplanetary mission from the West Coast and NASA's Insight, the first outer space robotic explorer to study the interior of Mars," a NASA announcer declared amid the rumble of takeoff at 7:05 a.m. ET, via NASA TV.
LIFTOFF! Humanity’s next mission to Mars has left the pad! @NASAInSight heads into space for a ~6 month journey to Mars where it will take the planet’s vital signs and help us understand how rocky planets formed. Watch: https://t.co/SA1B0Dglms pic.twitter.com/wBqFc47L5p
— NASA (@NASA) May 5, 2018
The Atlas V 401 rocket also carried two suitcase-size spacecraft, designed to orbit Mars, as it blasted into the dark and cloudy sky, which turned bright gold for seconds as the rocket ascended in a plume of smoke. NASA's previous interplanetary missions launched from Kennedy Space Center in Florida.
After a six-month journey, if it all goes as planned, InSight -- whose name is short for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport -- will touch down just north of the Martian equator on November 26, joining five other NASA spacecraft operating on and above Mars.
— NASA's Launch Services Program (@NASA_LSP) May 5, 2018
The 790-pound (358-kilogram) probe will then begin its two-year science mission to seek the "fingerprints" of the processes that formed the rocky planets of the solar system. It will measure the planet's "vital signs: 'its "pulse' (seismology), 'temperature' (heat flow) and 'reflexes' (precision tracking)," according to NASA.
The explorer doesn't have wheels, so it can't roll around gathering up dirt to study. But it does have a 7.8-foot-long (2.4-meter) robotic arm. The arm will place a seismometer on the ground to detect "marsquakes" (think earthquakes, but on Mars, of course).
InSight also will burrow 10 to 16 feet into the crust of Mars, going 15 times deeper than any previous Martian mission, according to NASA.
The mission's principal investigator, Bruce Banerdt, told CNN he thinks InSight will fill the last gaping hole in NASA's exploration of Mars, some 75 million miles (121 kilometers) from Earth.
"We have mapped the surface of the entire planet in terms of visible features, topography, gravity and magnetic fields," he said. "We have studied the atmosphere, both globally and at the surface. We have roved around the surface at four different places, studying the geology and piecing together the history of the surface.
"But until now, the vast regions of the planet deeper than a few miles, or so, (have) been almost completely unknown to us," Banerdt said. "InSight will change that with a single stroke."
WATCH: Our administrator Jim Bridenstine shares his thoughts on the #InSight mission to Mars, the search for evidence of life beyond Earth, returning humans to the Moon and why Earth is his favorite planet. pic.twitter.com/H4wiJNrFNK
— NASA (@NASA) May 5, 2018
InSight's mission aims ultimately to answer age-old questions -- Are we alone in the universe? Is there potential for life on a planet that's not Earth? -- NASA Administrator Jim Bridenstine said in a video tweeted Saturday by the space agency.
"This is an important mission not just for the United states but an important mission for the world," he said, "so we can better understand why planets change and ultimately understand even more about our own planet."