Colorado Skies: Venus shines bright

For the past four months, Northern Colorado observers have been treated to an excellent apparition of the planet Venus, the third brightest object in all the heavens. Currently the Twilight Queen blazes in the southwestern sky for more than four hours after sunset.

One needs only a single glance at this marvelous object as it gleams against a backdrop twilight sky to appreciate and understand how it came to be named for the goddess of beauty and love.

Three and a half centuries of telescopic observations of Venus added only mystery to the planet’s renowned beauty, for the planet is surrounded by a dense atmosphere that effectively hides the surface of this outwardly lovely world from the visual gaze of terrestrial observers. Astronomers could determine that the size, mass, and surface gravity of Venus were very close in value to those of the Earth, thus rendering the planet a “twin” of the Earth in the minds of the astronomers of the early 20th century. As a result, speculation, as late as the 1950s about possible life forms on Venus actually rivaled that surrounding the storied planet Mars.

Such speculation ranged from a tropical world populated by a variety of otherworldly saurians to an arid desert world devoid of any but the hardiest of life forms. In the 1950s several UFO books claimed that Venus was the planet of origin for the authors’ extraterrestrials, and the late Zsa Zsa Gabor’s infamous foray into the realm of science fiction movies, “Queen of Outer Space,” had as its setting the planet Venus.

Unlike the Martian mythology which continues steady and strong to this day, Venusian speculation collapsed before the onslaught of Space Age science. Using a combination of space probes and Earth-based telescopes that operate at wavelengths enabling astronomers to “see” through the dense cloud banks of Venus, astronomers have managed to piece together a portrait of the planet which is anything but conducive to life.

The atmospheric pressure at the surface of Venus is about 90 times that of the Earth’s atmosphere at sea level. The atmosphere of Venus consists of about 96 percent carbon dioxide, which serves to trap incoming solar radiation to produce an extreme version of the greenhouse effect. As a result, the temperature on the surface of Venus is more than 900 degrees Fahrenheit, a temperature that is hot enough to melt tin, lead, and zinc, and easily high enough to have long since boiled away any oceans that may have once existed on the surface.

Although the bulk of the atmosphere of Venus is composed of inert carbon dioxide, the remaining 4 percent of the atmosphere consists of substances that have turned the Venusian cloud banks into a virtual cauldron of acidic reactions involving some of the most caustic substances known to science, including hot, vaporous nitric, hydrochloric, and sulfuric acids.

Such an incredibly hostile environment has been confirmed by numerous instrument packages that over the years have been landed on the planet’s surface by both the U.S. and the former Soviet Union. Unlike the soft-landers on Mars that have transmitted months and months of images and data from the surface of the Red Planet, no spacecraft that has reached the surface of Venus has survived more than an hour of so before succumbing to the planet’s environmental savagery. Thus, has a world seemingly wrapped in beauty and loveliness been found to be as hostile as one could imagine.

May you all enjoy a happy and prosperous New Year.

Elsewhere in the Sky: The planet Mars glows above and to the left of Venus all month long. The Red Planet is not nearly as bright as Venus, but nonetheless shines respectably in the early evening western sky.

The planet Jupiter rises about midnight and can be found as a prominent yellowish-white object to the north of the bright bluish Virgo star Spica

The planet Saturn rises about two hours ahead of the sun and can be seen as a golden-hued object just to the east of the bright reddish Scorpius star Antares.

The elusive planet Mercury is visible during the last three weeks of January as a reddish orange object below and to the left of Saturn for about an hour before sunrise.