One and a half years after a mirror created by Brigham Young University students left Earth onboard the European Space Agency’s Mars Express spacecraft, a second mirror – this one on the Venus Express – will be launched from Baikonur, Kazakhstan.
Astronomers will use the spacecraft’s seven instruments to determine why a planet so similar to Earth in terms of orbit, size and mass is so inhospitable. The BYU mirror is part of the “ASPERA” device designed to measure the rate at which Venus’ atmosphere is being eroded by solar winds, which has implications for Earth’s own weather system. ASPERA stands for “analyzer of space plasma and energetic atoms.”
“Students did great work on this, and we are all very excited to see the fruits of their labors go into space,” said David Allred, professor of physics and project advisor. “For the undergraduates who got to be involved in research, this is about the coolest thing they could imagine. It’s really a once-in-a-career experience for them to have something they’ve worked on orbit another planet.”
The BYU students’ contribution to the ASPERA makes the instrument’s readings accurate and useable for scientific interpretation. Sarah Barton, Chris Verharen, Niki Brimhall and Amy Baker were the students who worked on the project.
“It’s really a neat thing to know that something I helped build will be orbiting Venus, taking measurements,” said Barton. “Some of the other projects I’ve worked on are a little less glamorous and a little less understandable, but people can visualize this project, which is nice for a change.”
Baker added, “It was interesting to collaborate with the European Space Agency and get another take on things. The experience has given me confidence that the work I produce is useful to other people.”
The students started in winter of last year by reformulating a special coating for the mirror. This finish of chromium and magnesium fluoride was formed using evaporation. Inside a vacuum chamber, the mirror’s titanium base was held over an intense heat source. When the chromium and magnesium fluoride came in contact with the heat, they evaporated and adhered to the titanium.
“Those are fairly common materials, but students figured out the most effective mixture and method for coating the mirror,” said Allred.
The European Space Agency has built the Venus Express using much of the design of its predecessor, the Mars Express. The newer ship has been adjusted to allow it to face Venus’ environment. However, the BYU-built mirror on board the Venus Express is identical to the one students built for the ASPERA device currently orbiting Mars.
Venus, which has temperatures that hover at 450 degrees Celsius and a carbon dioxide atmosphere that rains sulfuric acid, is a bit of a mystery, said Allred. The mission will provide the most comprehensive study of the planet’s atmosphere, which is an example of runaway global warming.
“People usually think of erosion as wind or water removing soil, but planetary scientists also talk about solar wind and how it can erode things it comes in contact with,” said Allred. “In the case of Venus, hydrogen and oxygen atoms are being knocked farther into space. If it weren’t for that, they might recombine and remain on the planet.”
Earth has a magnetic field which helps prevent the same type of erosion from taking place, while Mars and Venus do not, said Allred.
“Earth is special,” said Allred. “And what scientists are trying to determine with these spacecraft is why has our planet been so hospitable to life for such a long time. Did Mars or Venus ever have life and then the planets went bad? If so what made them go bad? If we can answer those questions, then perhaps we’ll be able to do something to prevent the same situation on Earth.”