enus has managed to hide many secrets in its toxic swirls, but we might be on the verge of revealing one of them.
NASA’s Planetary Science Deep Space SmallSat Studies (PSDS3) is now funding a team of scientists and engineers at its Goddard Space Flight Center to advance a CubeSat concept for a mission to investigate what is absorbing so many UV rays in the uppermost layer of its clouds.
When you look at a picture of Venus in visible light, the planet really isn’t all that attractive. It doesn’t have the cosmic rings of Saturn or the whorls of Jupiter or the otherworldly blue shades of Neptune and Uranus. Flip the switch to UV and suddenly you’re looking at a magical marbled orb. This is because something —what exactly is the thing scientists want to find out—is absorbing ultraviolet rays. How dark the swirls get depends on how much UV light they absorb, but we still don’t know what the absorber actually is.
The CubeSat UV Experiment aka CUVE that NASA is backing will use ultraviolet-sensitive instruments including a spectrometer, a miniature UV camera and an unprecedented carbon-nanotube light-gathering mirror, which admittedly sounds like something straight out of Star Trek, to probe the poisonous Venusian atmosphere.
The only things Venus has in common with Earth are its size and structure. Besides that, its carbon dioxide atmosphere congested with sulfuric acid clouds is nowhere you’d want to live even if you could. Unless you’re turned on to the idea of a place where so much heat is trapped by a runaway greenhouse effect that the surface temperature becomes hot enough for even lead to be liquefied.
“Since the maximum absorption of solar energy by Venus occurs in the ultraviolet, determining the nature, concentration, and distribution of the unknown absorber is fundamental,” said CUVE Principal Investigator Valeria Cottini. “This is a highly-focused mission — perfect for a CubeSat application.”
CUVE is not the first mission sent to Venus by NASA or any other space program, but it could beam back some important revelations about the nature of the mysterious UV absorber. Some scientists theorize that the absorber is dragged to the tops of the planet’s clouds by convective processes and then whirled around by wind. What we do know from previously observing the planet is that the upper layer of those sulfuric acid clouds absorbs half its solar energy in the ultraviolet. The reason it looks so boring to us Earthlings is because other wavelengths, including those the human eye can actually see, are reflected or scattered into space.
It should take CUVE about a year and a half to reach Venus, where it will spend six months transmitting data from the alien atmosphere.