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From Mercury to Venus Help (page 2)

By — McGraw-Hill Professional
Updated on Sep 16, 2011

Attaining Orbit

In space there are no days and nights, except those that are produced artificially by the environmental systems on board the ship. In the living quarters of the Valiant there are no windows; the spinning of the gravity wheel would give you vertigo if you had windows to gaze from. However, there are pictures on the walls that change on a 24-hour cycle: landscapes with illumination that mimics the spectrum of the Sun on Earth’s surface. Your room has scenes of the rural Midwest. It is winter there right now, and the ship’s computer has determined that there has been plenty of snow in the last couple of weeks.

With realistic views out the “windows,” plenty of videos, music albums, a big library of books (the real, bound paper kind), an increasing workout schedule, good food, and a friendly crew, time goes fast. You wake up one morning and notice that all your “window” scenes have been reprogrammed to show the clouds of Venus swirling beneath the ship, whitish yellow, and a ruddy horizon that quickly fades away to black higher up.

“We are in an equatorial orbit,” explains the first officer over breakfast. “Our descent and flight will be along the equator, where the clouds race around the planet in four Earth days. You might notice, if you’re astute, that our orbit is retrograde.”

Venus spins contrary to all the other planets, that is, from east to west. The clouds, too, move in that direction. But what does the first officer mean by “flight”?

Shuttle Or Airplane?

The first officer will not attempt to land on Venus. “Landing craft have been devised that can survive conditions at the surface,” says the first officer, “but they are prohibitively expensive. We could never venture outside. All we could do would be sit around and peer out through thick, reinforced little portholes, like those in an undersea vessel.”

You will fly just beneath the clouds, in a hybrid shuttle/aircraft contraption reminiscent of the X-15 high-altitude craft used by the United States in the middle of the twentieth century. The upper-level winds rush along in the Venusian atmosphere at 400 kilometers (250 miles) per hour. “Venus has a huge, continuous, retrograde jet stream,” says the first officer, “and we are going to ride it once around the planet at an airspeed of 800 kilometers (500 miles) per hour.”

You do some quick calculating. Venus is about 40,000 kilometers in circumference; you will be moving at 800 + 400, or 1,200, kilometers per hour with respect to the surface. You decide to use your wrist calculator. “Calculator,” you say, “divide 40,000 kilometers by 1,200 kilometers per hour.” The little thing speaks up in its synthesized voice: “Solution: 33 hours and 20 minutes.”

You look quizzically at the first officer, who has now been joined by the captain who will wish you a happy trip.

“Don’t worry,” says the captain. “The planetary atmospheric reconnaissance vehicle (PARV) has a bathroom, a refrigerator, and a stove. Just like home.”

“There will be gravity for most of the trip,” says the first officer. During the ride beneath the clouds of Venus, during which you hope to get a good view of the surface on the sunlit side and some spectacular lightning shows on the nighttime side, you will be riding in an aircraft in a gravitational field almost of exactly the same strength as that at the surface of Earth.

“There are plenty of airsick bags,” says the first officer. “Venus can be a stormy place. I hope you didn’t eat too much for breakfast.”

A Wild Ride

The descent to the cloud tops goes smoothly, and the yellowish white barrier rises up to meet the shuttle just as you cross the twilight line into darkness. The rumble of the rocket engines fades as the first officer allows atmospheric drag to slow the aircraft down. “We won’t come through the bottom of the cloud layer until halfway through the night,” says the first officer as he sips on a glass of lemonade. “We are letting the atmosphere do all the work of slowing us down. The jet engines will start after we get under the clouds.”

The view out the windows turns from cream-colored to yellow, then orange, then rusty, then brown, and finally black. You imagine that you can hear the hiss of the sulfuric acid droplets as they eat away at the exterior of the craft, but you know this cannot actually be taking place because of the protective coatings that keep heat, radiation, and corrosion from affecting the shell of the vessel. Just as the windows have completely blacked over, you feel the first jolt.

For the next 8 hours you lie flat on your back, your seat all the way down to horizontal, strapped in tight, and try to sleep. You don’t get airsick, but you worry that something will go wrong, the craft will shake apart, and you will be sent tumbling down into hell. Then finally the violent ride becomes smooth, and you hear the whooshing sound of the jet engines, which are now propelling the craft beneath the clouds of Venus at midnight.

All around the ship, lightning flashes: yellow, blue-white, brilliant white. With each flash, you can see the ceiling of cloud deck above. You cannot yet see the planet’s surface.

“We’re 40 kilometers (25 miles) above the landscape down there,” says the first officer. “You’ll be able to see it as soon as we come back into daylight. That will be in about 8 hours.”

“How high are we going to fly?” you ask.

“We have leveled off now,” says the first officer. “This is as low as we dare go. If we went a little lower, the atmosphere would slow us down too much. Then we would lose altitude, and the drag would increase further, slowing us down still more, and we would plunge to the surface and crash.”

“That is not what I want to hear,” you say.

“Don’t worry,” says the first officer. “I am well trained.”

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