Roger Wiens and his older brother, Doug, spent part of the summer of 1971 building a telescope from scratch to observe the close approach of Mars.

The two brothers from the small southwest Minnesota town of Mountain Lake had been assembling rockets and gazing at the stars for years, but the telescope was a new challenge. They bought supplies using money earned on their paper route and, absent a proper stand, mounted their contraption on a fence post.

Almost 50 years later, Roger Wiens is still helping build objects for space exploration. But his latest creation won't be looking up at Mars; it's attached to a rover rolling across the Red Planet's surface.

Wiens is the principal investigator of the SuperCam instrument mounted on NASA's Perseverance rover, which landed on Mars at 2:55 p.m. Thursday.

"I never really thought that I would still be doing things like building instruments to use on Mars," Wiens said earlier this week.

The SuperCam is an updated and improved version of the ChemCam — of which Wiens was also the principal investigator — that was attached to the Curiosity rover that landed on Mars in 2012.

Mainly situated on the head of the rover, SuperCam uses different types of lasers to capture the color spectrum, mineral structure and atomic composition of rocks and soil on Mars. It also has a camera and a microphone.

"All of these different techniques contribute to us really characterizing the geology," Wiens said. "We think of SuperCam as a geological observatory."

The Perseverance rover launched into space on July 30, with the main focus of looking for signs of ancient life and collecting rocks to return to Earth for study. It weighs about 2,260 pounds is about 7 feet tall, 10 feet long and 9 feet wide.

There are seven payload instruments on Perseverance including SuperCam. Wiens is also a co-investigator of Perseverance's SHERLOC instrument, which is on the rover's arm and is looking for evidence of past life on Mars.

Wiens, who works out of the Los Alamos National Laboratory in New Mexico, said he has been a space junkie for as long as he can remember. The Mountain Lake community where he grew up emphasized education and understanding the world around them, and that attitude has stuck with him throughout his career.

His brother Doug Wiens — now a professor at Washington University in St. Louis who researches earthquakes in the Pacific Ocean and Antarctica — added that they grew up in an encouraging environment both at home and in school.

Their father, Alvin Wiens, said he recognized his sons' intelligence early and enjoys seeing them continue to follow their passions. Now 90, he planned to watch the landing from his home in Mountain Lake.

"It's good to see," he said. "It's good to see that [Roger and Doug] are accomplishing things."

Roger Wiens followed his older brother to Wheaton College in Illinois before returning and earning his Ph.D. at the University of Minnesota. He worked with Prof. Robert Pepin and his team at the U studying Mars while in grad school.

Within a year of starting grad school, Wiens was already spearheading the U's Mars research efforts, Pepin said.

Pepin added there is only one other student he worked with in his five decades at the U that can even compare to Wiens in terms of productivity and imagination.

"Roger is the only student I can ever remember whose Ph.D. thesis entirely consisted of summaries of work that he already published — that's extremely rare for graduate students," Pepin said. "His papers are still landmarks in at least our Mars research efforts and, in fact, in the national and international Mars research effort."

He added that Wiens is a remarkable person and described his pride in his former student as "boundless."

Doug Wiens no longer works alongside his brother building rockets and telescopes, but he said it is always fun when the two chat about Roger's work.

"I'm really happy for his success," Doug said. "He worked really hard to get where he is."

Peter Warren • 612-673-1713