Venus

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Venus Astronomical symbol of Venus
Venus
Names
How to say it how to say: /ˈviːnəs/
Adjective Venusian or (rarely) Cytherean, Venerean
Orbit
Reference date J2000
Longest distance from the Sun 108,942,109 km
0.728 231 28 AU
Shortest distance from the Sun 107,476,259 km
0.718 432 70 AU
Longest distance from the center of its orbital path
("semi-major axis")
108,208,930 km
0.723 332 AU
How egg-shaped its orbit is
("eccentricity")
0.006 8
How long it takes to complete an orbit 224.700 69 day
0.615 197 0 yr
1.92 Venus solar day
How long an orbit seems to take
(from the central body)
583.92 days[1]
Average speed 35.02 km/s
Angle above the reference plane
("inclination")
3.394 71° to Ecliptic
3.86° to Sun’s equator
2.19° to Invariable plane[2]
Longitude of where it comes up through the reference plane 76.670 69°
Angle between its shortest distance from what it orbits around and where it comes up through the reference plane
("argument of periapsis")
54.852 29°
Natural things which orbit around it None[3]
Size and Other Qualities
Average distance from its center to its surface 6,051.8 ± 1.0 km[4]
0.949 9 Earths
Flatness at the poles 0[4]
Area of its surface 4.60×108 km²
0.902 Earths
Volume inside it 9.38×1011 km³
0.857 Earths
Mass 4.868 5×1024 kg
0.815 Earths
Average density 5.204 g/cm³
Gravity at its surface 8.87 m/s2
0.904 g
Slowest speed able to escape into space
("escape velocity")
10.46 km/s
How long it takes to turn around one time
(in relation to the stars)
-243.018 5 day
Turning speed 6.52 km/h (1.81 m/s)
Angle at which it turns
(in relation to its orbit)
177.3°[1]
Long. around the celestial equator
("right ascension")
18 h 11 min 2 s
272.76°[5]
Angle above the celestial equator
("declination")
67.16°
How much light it reflects 0.65 (geometric) or 0.75 (bond)[1]
Surface temp. Min. Avg. Max.
Kelvin 735 K[1][7][8]
Celsius 461.85 °C
Seeming brightness
("apparent magnitude")
up to -4.6[1] (crescent)
-3.8 (full)[6]
Seeming size
("angular diameter")
9.7" – 66.0"[1]
Air
Pressure 93 bar (9.3 MPa)
Make up ~96.5% 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
trace Carbonyl sulfide
trace Hydrogen chloride
trace Hydrogen fluoride

Venus is the second planet from the Sun.[9] It is a terrestrial planet because it has a solid, rocky surface. The other terrestrial planets are Mercury, Earth and Mars. Astronomers have known Venus for thousands of years. The ancient Romans named it after their goddess Venus. Venus is the brightest thing in the night sky except for the Moon. It is sometimes called the morning star or the evening star as it is brightest just before the sun comes up in the morning, and just after the sun goes down in the evening. Venus comes closer to the earth than any other planet does.

Venus is sometimes called the sister planet of Earth as they are quite similar in size and gravity. In other ways the two planets are very different. Venus' atmosphere (air) is mostly carbon dioxide with clouds of sulfuric acid.[10] Sulphuric acid is a chemical that is very poisonous to humans. The thick atmosphere has made it hard to see the surface, and until the twenty-first century many people thought things might live there. The pressure on Venus' surface is 92 times that of Earth. Venus has no moons. Venus spins very slowly on its axis and it spins in the opposite direction to the other planets.

Physical Properties[change | change source]

Global view of the surface of Venus (Magellan spacecraft)

Venus is a terrestrial planet so, like the Earth, its surface is made of rock. Venus is much hotter than Earth. All the carbon dioxide in the atmosphere acts like a blanket, trapping heat from the Sun. This effect is called the greenhouse effect and it is very strong on Venus. This makes the surface of Venus the hottest of any planet's surface in the Solar System with an estimated average temperature of 480 °C (896.0 °F).[11][12] This is hot enough to melt lead or zinc.

Geography[change | change source]

Size comparison of the terrestrial planets including Venus

Venus has no oceans because it is much too hot for water. Venus' surface is a dry desert. It is about 80% smooth, rocky plains. Two higher areas called continents make up the north and south of the planet. The north is called Ishtar Terra and the south is called Aphrodite Terra. They are named after the Babylonian and Greek goddesses of love.[13]

Atmosphere[change | change source]

Venus' atmosphere is mostly carbon dioxide and nitrogen gas with clouds of sulphuric acid. Because the atmosphere is so thick or dense the pressure is very high. The pressure is 92 times the pressure on Earth, enough to crush many things.

It is impossible to see the planet's surface from space as the thick cloud layer reflects 60% of the light that hits it. The only way scientists are able to see it is by using infrared and ultraviolet cameras and radar.

Transit of Venus[change | change source]

Venus can sometimes be seen passing between the sun and earth. Venus looks like a black dot when seen through a special telescope. These "transits" happen in pairs eight years apart. Then it's more than a hundred years to the next pair.

Related pages[change | change source]

References and Notes[change | change source]

  1. 1.0 1.1 1.2 1.3 1.4 1.5 Williams, David R. (April 15, 2005). "Venus Fact Sheet". NASA. http://nssdc.gsfc.nasa.gov/planetary/factsheet/venusfact.html. Retrieved 2007-10-12.
  2. "The MeanPlane (Invariable plane) of the Solar System passing through the barycenter". 2009-04-03. http://home.comcast.net/~kpheider/MeanPlane.gif. Retrieved 2009-04-10. (produced with Solex 10 written by Aldo Vitagliano; see also Invariable plane)
  3. Harvey, Samantha (2011-02-16). "NASA: Solar System Exploration: Planets: Venus: Moons". NASA. http://solarsystem.nasa.gov/planets/profile.cfm?Object=Venus&Display=Moons. Retrieved 2011-03-31.
  4. 4.0 4.1 Seidelmann, P. Kenneth; Archinal, B. A.; A’hearn, M. F.; et al. (2007). "Report of the IAU/IAGWorking Group on cartographic coordinates and rotational elements: 2006". Celestial Mechanics and Dynamical Astronomy 90: 155–180. doi:10.1007/s10569-007-9072-y . http://adsabs.harvard.edu/doi/10.1007/s10569-007-9072-y. Retrieved 2007-08-28.
  5. "Report on the IAU/IAG Working Group on cartographic coordinates and rotational elements of the planets and satellites". International Astronomical Union. 2000. http://www.hnsky.org/iau-iag.htm. Retrieved 2007-04-12.
  6. Espenak, Fred (1996). "Venus: Twelve year planetary ephemeris, 1995–2006". NASA Reference Publication 1349. NASA/Goddard Space Flight Center. http://sunearth.gsfc.nasa.gov/eclipse/TYPE/venus2.html. Retrieved 2006-06-20.
  7. "Venus: Facts & Figures". NASA. http://sse.jpl.nasa.gov/planets/profile.cfm?Object=Venus&Display=Facts&System=Metric. Retrieved 2007-04-12.
  8. "Space Topics: Compare the Planets: Mercury, Venus, Earth, The Moon, and Mars". Planetary Society. http://www.planetary.org/explore/topics/compare_the_planets/terrestrial.html. Retrieved 2007-04-12.
  9. in our Solar System
  10. "The Atmosphere of Venus". http://www.windows.ucar.edu/tour/link=/venus/atmosphere.html.
  11. "Venus - an overview". http://filer.case.edu/sjr16/advanced/venus.html.
  12. "Temperature on the Surface of Venus". http://hypertextbook.com/facts/2000/GeorgeRyabov.shtml.
  13. Batson R.M., Russell J.F. (1991), Naming the Newly Found Landforms on Venus, Abstracts of the Lunar and Planetary Science Conference, v. 22, p. 65

Other websites[change | change source]