Venus will receive a visitor tonight — a spacecraft on its way to Mercury. And a lot of folks here on Earth will be looking on.

BepiColombo was launched two years ago. Its mission is to orbit Mercury. But getting there isn’t easy. The craft needs to slow down and sculpt its path around the Sun to intersect Mercury at the right speed and time. So it will fly past Venus twice and Mercury six times, honing its orbit with each pass.

The first Venus encounter comes tonight. BepiColombo will swing just 6600 miles from the planet. And it’ll use most of its instruments to observe it. Among other things, it will measure Venus’s magnetic field and its interaction with the solar wind.

The craft also will peer into the middle layers of Venus’s blanket of clouds — something that no craft has done in decades. Something in that layer absorbs certain wavelengths of light. And some scientists have speculated that it could be microscopic life.

Another craft is orbiting Venus, so the two missions will coordinate their observations. Several observatories on Earth will be studying the planet as well. And so will quite a few amateur observers, whose work can provide a more complete picture of Venus during the encounter — a quick visit en route to another planet.

Venus is the “morning star,” so you don’t need a telescope to see it. By the time Venus rises tomorrow, BepiColombo will have left it behind — until the next encounter, in August.

Script by Damond Benningfield

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