More visits planned to Earth's 'evil twin'

The planet Venus, often referred to as Earth’s “evil twin,” is expected to receive another visit from two U.S. spacecraft around the end of this decade.

According to a NASA press release, these two new missions will be used to better understand how “Venus became an inferno-like world.”

Venus is considered to be the most hostile planet in our solar system. It has a thick and toxic atmosphere that is primarily composed of carbon dioxide. There are also yellowish type clouds made of mostly sulfuric acid. This combination of greenhouse gases has led to runaway global warming as temperatures at the surface of Venus are estimated to be near 900 degrees Fahrenheit, hot enough to melt lead.

Temperatures on Venus are even higher than Mercury’s, the planet closest to the sun. During the day, Mercury’s high is close to 800 degrees Fahrenheit.

The dense cloud cover on Venus will reflect much of the sunlight. On a clear night, depending on the position of Venus in relation to Earth, Venus will often appear as one of the brightest lights in the night sky. Sometimes the planet is so bright that it has been mistaken for a UFO.

Venus is the second closest planet to the sun and its size is very similar to Earth's. However, Venus spins backward as the sun will rise in the west rather than in the east.

It orbits the sun about every 225 Earth days, and one day on Venus is the equivalent of 243 Earth days. Despite the very slow rotation, winds on the harsh planet will often blow at hurricane force.

According to NASA, more than 40 spacecraft have been sent to Venus. The Mariner 2 scanned the cloud cover on Dec. 14, 1962. In the early 1990s, NASA’s Magellan used sophisticated radar and mapped the planet’s surface down to a resolution of less than 1,000 feet. At the end of its mission, Magellan was sent into the Venusian atmosphere to get aerodynamic data before burning up on entry.

Thanks to the Magellan’s mapping, it was discovered that much of the surface is covered with gently rolling plains that were likely to have been shaped by volcanic activity. A study in early 2020 showed evidence that Venus is still volcanically active.

As far as landing on Venus, only four spacecraft have ever accomplished that task and managed to send colorized panoramic images of the planet’s surface back to Earth. They were missions from the Soviet Union in 1975 and in 1982 that showed yellow skies and desolate landscapes.

These spacecraft managed to survive the intense heat on the planet’s surface for as little as 20 minutes, but one of the craft lasted about 2 hours.

By late this decade, perhaps as early as 2028, NASA will launch DAVINCI+, which is Deep Atmosphere Venus Investigation of Noble gases, Chemistry, and Imaging. This spacecraft will travel through the atmosphere to measure its composition to determine how it formed and evolved.

Many scientists believe that Venus once had oceans similar to Earth and this new mission may reveal the history of water on Venus. DAVINCI+ will also take high resolution pictures of particular geological features.

The second spacecraft from NASA will be the VERITAS, which is the Venus Emissivity, Radio Science, InSAR, Topography and Spectroscopy. Its purpose will be to better map the surface of Venus using 3D reconstructions to see the planet’s geologic history and why it developed differently than Earth.

VERITAS will also be able to determine if active volcanoes are releasing water vapor into the atmosphere.

LOCAL WEATHER

The big high pressure system in the Far West continues to be super-strong. There may be some shower and isolated thunderstorm activity over the next week to 10 days, but rainfall amounts are expected to be light.

Based on the current pattern, this would be the driest first half of June in recorded history. June’s normal precipitation in Coeur d’Alene is 1.93 inches.

Unless we see a big increase in rainfall or a few thunderstorms that produce moderate to heavy rainfall, June will be the fourth month in a row with precipitation totals below normal.

Extended periods of below-average precipitation in North Idaho do not happen very often, but in 2017, not much rain fell from June through August. In 2007, there were eight months with moisture totals below normal. That occurred from April through November.

Conditions are still looking drier than normal between now and at least into July, which would increase the chances for another tough fire season. In August and September, we believe that the weather will start to turn wetter, a complete contrast to what we had in 2020 when only .12 inches was reported over those two months.

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Contact Randy Mann at randy@longrangeweather.com