Planet Venus
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Facts and Information
Planet Venus
planet venus Image of the planet taken by the Pioneer Venus Orbiter in 1979.

Maat Mons
Maat Mons Magellan radar image of the Venusian volcano Maat Mons.
Planet Venus Facts
  • Venus is the second planet from the sun and very similar in size to the Earth, its diameter is only 400 miles (644 km) smaller than Earth.
  • At its closest point to Earth the planet is a mere 24 million miles away (38 million km).
  • It orbits the sun at an average distance of 67 million miles (108 million km).
  • The planet orbits around the sun every 225 days but rotates on its own axis slower than any other planet, taking 243 days compared to 24 hours on Earth. Meaning a day on Venus is longer than its year! It also rotates in the opposite direction of the other planets.
  • It is surrounded by extremely thick cloud making it impossible to see the surface from orbit without radar or radio equipment.
  • The force of gravity is only 12% less than we have on Earth but the extreme weight of atmospheric pressure would crush a human.
  • Apart from the moon Venus is the brightest object in the night sky.
  • It was the first planet to be observed by a passing spacecraft.
Viewing Venus

The great thing about Venus is that it’s always easy to find, it’s the brightest "star" to rise just as the sun is setting, it's so bright it’s impossible to miss. As Venus is an inner planet it goes through phases just like the moon, from full to a thin crescent. Counter intuitively Venus is actually much brighter when it’s a thin crescent, this is because at this point it's much closer to Earth.

As Venus is so close and bright you don’t need a super duper telescope to view it, even if you had a more expensive telescope there isn’t actually a lot of detail to make out. This is because Venus is covered in very thick cloud so viewing any surface markings is impossible, although you may be able to make out some cloud detail. Even so it’s still a thrill to observe our closest neighbor and watch it go through its different phases.

Below are a couple of recommended low cost scopes that are perfectly adequate for observing Venus.
ORION XT4.5
The Orion Skyscanner is incredibly easy to set up and you could be checking out Venus within minutes of taking it out the box. It has a good enough aperture to capture dark and light areas in the planet’s clouds.
The Meade 20218 NG-70SM comes with a sturdy tripod and is a very good entry level telescope. It’s great value for money at only around $75 and will provide you with very reasonable views of Venus.
More Venus Information
surface of venus
Artist's impression of the surface of Venus.

Surface
About 65 percent of Venus is covered by flat plains, it also has mountains, canyons and valleys. There are thousands of volcanoes on Venus, some up to 150 miles (240km) in diameter. Venus also has ring-like structures called coronae which do not exist on Earth.


Atmosphere
The atmosphere of Venus is heavier than any other planet. It consists mainly of carbon dioxide with small amounts of nitrogen and water vapor.


Temperature
Extremely hot! The temperature at the uppermost clouds of Venus average about 13C (55F) however the surface temperature is a baking 465C (870F), the hottest surface of any planet in the solar system.


Moons & Origin of Name
Venus has no moons.
The planet was named by the Romans after the Goddess of Love.


Life on Venus
Due to the extreme heat it is highly unlikely any lifeforms could exist on the surface, airborne life forms could exist in temperate high clouds.



Venus, Earth's Twin?
surface of venus
Venus is often referred to as Earth’s sister planet or even twin. This is mainly due to the fact that it is very similar in size to our own planet. As it turns out we share other similarities, the mass, density and gravity of Venus are all very similar to Earths. Indeed studies have shown that a few billions years ago it had liquid water flowing over its surface and may well have harbored primitive lifeforms. Unfortunately for the planet there are also fundamental differences which means that while Earth is a hospitable world teeming with life, Venus is a choked, oven baked desert.

The atmospheres of both worlds are very different, Earth’s is thin and nitrogen based whereas the atmosphere on Venus is extremely thick and composed almost entirely of carbon dioxide. Ninety percent of Earth’s atmosphere is within just 6 miles (10 km) of its surface, on Venus it would be 30 miles (50 km) from its surface before reaching 90% of its atmosphere. As a result of having the heaviest atmosphere of any planet in the solar system atmospheric pressure on Venus is a massive 90 times stronger than on Earth, the equivalent of being more than a kilometer under the ocean, a human being would be crushed in these conditions. Perhaps the biggest difference is the intense heat, surface temperatures can reach an incredible 465C (870F) which is hot enough to melt lead.

So where did it all go wrong for our twin planet? Well unfortunately it was just too close to the sun. The water it once had flowing across its surface quickly evaporated and without the cleansing effect of rain huge amounts of carbon dioxide built up in its atmosphere from intense volcanic activity. This created a runaway greenhouse effect, our twin reached the point of no return ending up with the hottest surface temperature of any planet in the solar system.

Images & Video
Surface of Venus (Venera 13) 1981
surface of venus
Radar images of the Venusian surface
Venus under the clouds
venus radar image

Future and Past Missions to Venus
21.
Planet-C (Akatsuki)
planet-c Launch: 2010
Arrival: 2011
Agency: JAXA (Japan)

Designed to study the atmospheric dynamics of the planet. It will also measure atmospheric temperatures and look for evidence of volcanic activity and lightning.

Update: Due to an unexpected accident the Akatsuki Venus Climate Orbiter failed in its orbit insertion around the planet.

20.
Venus Express
venus express Launch: November 2005
Arrival: April 2006
Agency: ESA (Europe)

Venus Express is currently in orbit around Venus and has recently indicated that the planet is still volcanically active.


19.
Messenger
messenger Launch: August 2004
Arrival: October 2006 (Orbit March 2011)
Agency: NASA

Messenger has made 2 flybys of the planet on its way to Mercury. The opportunities were used to test scientific equipment on the craft.

18.
Cassini-Huygens
cassini-huygens Launch: October 1997
Arrival: April 1998
Agency: NASA/ESA (Europe)

The spacecraft used the planet for two gravity assists on its way to Saturn.

17.
Magellan
magellan Launch: May 1989
Arrival: August 1990
Agency: NASA

By the end of its mission Magellan had mapped 98% of the planet using advanced radar techniques.


16.
Galileo
galileo Launch: October 1989
Arrival: February 1990
Agency: NASA

Galileo flew past Venus on its way to Jupiter taking 81 images of the planet.

15.
Vega 1
vega 1 Launch: June 1983
Arrival: October 1983
Agency: Soviet Union

Vega 1 deployed a probe into the planet's atmosphere which measured temperature, pressure and wind velocity.

14.
Venera 15 and 16
venera 15 Launch: June 1983
Arrival: October 1983
Agency: Soviet Union

Venera 15 and 16 created a radar map of the planet over a joint mission lasting 8 months.

13.
Venera 14
venera 14 Launch: November 1981
Arrival: March 1982
Agency: Soviet Union

Venera 14's lander successfully touched down on the planet's surface sending back 14 images and a mechanical arm collected a sample for testing. The craft survived for 57 minutes before finally succumbing to the intense pressure. (Lander pictured left).


12.
Venera 13
venera 13 Launch: October 1981
Arrival: March 1982
Agency: Soviet Union

Venera 13's lander successfully touched down sending back the first color images of the surface. It also collected and examined a sample with a mechanical arm. The craft survived for 2 hours before succumbing to the extreme heat and pressure. (Orbiter pictured left).


11.
Venera 11 and 12
venera 11 Launch: September 1978
Arrival: December 1978
Agency: Soviet Union

Both landers successfully touched down on the surface sending back data about the atmospheric composition and clouds of the planet, evidence of thunder and lightning as well as the presence of carbon monoxide.

10.
Pioneer Venus 2
Pioneer Venus 2 Launch: May 1978
Arrival: December 1978
Agency: NASA

Pioneer Venus 2 consisted of four separate atmospheric probes. Each probe took atmospheric measurements as they descended through the cloud layer. One of the probes survived to transmit data for over an hour after it impacted with the surface.


9.
Pioneer Venus 1
Pioneer Venus 1 Launch: May 1978
Arrival: December 1978
Agency: NASA

Used radar to map most of the planet. The spacecraft remained in orbit until August of 1992, when it used up all its fuel and burnt up in the atmosphere.


8.
Venera 10
venera 10 Launch: June 1975
Arrival: October 1975
Agency: Soviet Union

Successfully landed a probe on the planet's surface. It transmitted images from the surface and sent back data about clouds and the surface environment.

7.
Venera 9
venera 9 Launch: June 1975
Arrival: October 1975
Agency: Soviet Union

Successfully landed a probe on the planet's surface. It became the first spacecraft to transmit a picture from the surface of another planet. Also sent back information on the Venusian clouds, atmospheric composition, and light levels.


6.
Venera 8
venera 8 Launch: March 1972
Arrival: July 1972
Agency: Soviet Union

Successfully landed a probe on the planet's surface. The probe transmitted data for 50 minutes, confirming a very high surface temperature and crushing atmospheric pressure. It also measured the light level on its surface and found it suitable for surface photography.


5.
Venera 7
venera 7 Launch: August 1970
Arrival: December 1970
Agency: Soviet Union

Successfully landed a probe on the planet's surface. The probe became the first spacecraft to return data from the surface of another planet. It reported surface temperatures of 475°C and atmospheric pressures 90 times greater than Earth's.

4.
Venera 5 and 6
venera 7 Launch: January 1969
Arrival: May 1969
Agency: Soviet Union

Venera 5 and 6 descended into the Venusian atmosphere sending back data for just over 50 minutes before succumbing to the intense pressure.

3.
Mariner 5
mariner 5 Launch: June 1967
Arrival: October 1967
Agency: NASA

Flew within 4000 miles (2,400 km) of the planet measuring a surface temperature of 267C.

2.
Venera 4
venera 4 Launch: June 1967
Arrival: October 1967
Agency: Soviet Union

Dropped several instruments into the atmosphere before descending itself. It revealed an atmosphere made up almost entirely of carbon dioxide, extremely high temperatures and atmospheric pressure.


1.
Mariner 2
mariner 2 Launch: August 1962
Arrival: December 1962
Agency: NASA

Mariner 2 was the first spacecraft to successfully fly by the planet. It detected ground temperatures as high as 428C (800F). Radio contact was lost on January 3, 1963.



Planet Venus Statistics
Comparison with Earth
Diameter: 7,521 miles (12,104 km)
Average Distance from Sun: 67 million miles (108 million km)
Orbital Period: 225 days
Rotation Period: 243 days

Maximum Surface Temperatures: 465C (870F)
Minimum Surface Temperatures: same as maximum

Gravity: 8.87 m/s2 (91% Earth's Gravity)
Density: 5.24 g/cm3 (95% Earth's Density)
Mass: 4.8685 x 1024 kg (81.5% Earth's Mass)
Volume: 9.284 x 1011 km3 (88% Earth's Volume)

Atmosphere: 96% Carbon dioxide, 3.5% Nitrogen, 0.015% Sulfur dioxide, 0.007% Argon, 0.002% Water vapor, 0.001 7% Carbon monoxide, 0.001 2% Helium,
0.000 7% Neon.
Diameter: 7,926 miles (12,756 km)
Average Distance from Sun: 93 million miles (150 million km)
Orbital Period: 365.24 days
Rotation Period: 23.934 hours

Maximum Surface Temperatures: 58C (136F)
Minimum Surface Temperatures: -88C (-126F)

Gravity: 9.766 m/s2
Density: 5.515 g/cm3
Mass: 5.9737 x 1024 kg
Volume: 1.0832 x 1012 km3

Atmosphere: 78.08% nitrogen, 20.95% oxygen, 0.93% argon, 0.038% carbon dioxide, water vapor makes up around 0.4% of Earth's atmosphere depending on climatic conditions.
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