Date: June 2, 2012

Title: Encore: Exploring the Solar System: Venus

Podcaster: Thomas Hofstätter

Organization: The Hidden Space Project


This podcast originally aired on March 8th 2011

Description: The second step in the journey through the solar system is Venus. The planet has some very interesting phenomenons to offer and is in some points quite similar to our home planet. It’s observation reaches back until the beginning of intelligent humans

Bio: Born in 1993 near Vienna, Austria, Europe. Upper High School with focus on Computer Science.Interested in extreme small and extreme big, devious and uninvestigated things. My main aim is to bring astronomy to public and to establish secular interest in astronomy, physics and mathematics. Host of :: The Hidden Space Project :: at

Today’s Sponsor: This episode of “365 days of Astronomy” is sponsored by – Expanding your horizons in astronomy today. The premier on-demand telescope network, at dark sky sites in Spain, New Mexico and Siding Spring, Australia.”


Hello and welcome to this episode of 365 Days of Astronomy. My name is Thomas Hofstätter and I am the hoster of :: The Hidden Space Project :: at

[Leon:] And I’m Leon Dombroski from the state of Connecticut in the United States.

The probably most interesting planet in consideration of the earth’s past and future is the second of a virtual journey through the solar system. After Mercury has been discussed earlier, Venus is the next target that has interested humans for centuries and even millennia because of the bright shine that is visible for a longer period of time every few years.

[Leon:] The thick atmosphere causes this shine. In contrast to Mercury, Venus is massive enough to hold an own atmosphere. Indeed, the atmosphere is even much thicker than earth’s one. The pressure is about 93bar. An interesting fact is based in the composition of it: 96.5% are Carbon dioxide. Then come Nitrogen and some other gases.

As known from the much-discussed topic of global warming, Carbon dioxide is a key gas for climate. The gas lets the sunrays into the atmosphere until they touch the ground. Some of them are reflected again but aren’t able to escape the atmosphere again due to the high reflection factor. This triggers Venus to have an extremely hot surface. Indeed, Venus has a surface temperature of about 460C.

[Leon:] Another curious fact is the “false” rotation of Venus. Of all planets, Venus is the one with the lowest eccentricity of 0.01. But when comparing the planet with all the others of our solar system, it becomes clear that Venus is not rotating from the west to the east, but from the east to the west. This means that Venus is rotating retrograde clockwise around it’s own axis and counter clockwise around the sun.

Some scientists though think that Venus is indeed rotating counter clockwise around it’s own axis, but has an extreme axial tilt of about 177∞. What caused this different rotation is not known clearly. One possible explanation is, that a greater object hid Venus some time, which changed the axial tilt. This explanation doesn’t go hand in hand with the low eccentricity of the planet’s orbit.

[Leon:] After this fact was known, scientists asked themselves, what exactly caused this strange rotation of Venus. Therefore, several probes were launched even in the early times of spaceflight. The first probes just observed Venus from outside the atmosphere scanning the surface using radar.

The first probes to enter the atmosphere and even land on the hot surface of Venus mostly were constructed by the Soviet Space Agency in the 1960s and 1970s. Venera 7 performed the first controlled touchdown on Venus’ surface in December 1970. The probe stayed in contact with the control base for 23min until it broke due to the high temperature and pressure.

[Leon:] But as early as Galileo Galilei pointed his telescope to the sky, another curious fact about Venus was known, which indeed seems quite obvious to us: Venus has phases similar to the moon.

This was one reason for Galilei to support the Copernican studies about heliocentrism. Like visible at the moon, the phases are caused by Venus’ own shadow from our point of view. The phases of Venus are visible even through smaller amateur telescopes.

That’s it for today. I hope, you enjoyed it. If you have any questions, comments or suggestions, write me an email to hidden-space (at) gmx (dot) at or visit me at my website at

Thanks for listening and clear-skies!
[Leon:] Good bye for now!

New stories are to come soon!



  • Mass: 4.8685*1024kg
  • Radius: 6,051.8±1.0km (mean)
  • Aphel: 108,942,109km (0.728 231 28AU)
  • Perihel: 107,476,259km (0.718 432 70AU)
  • Orbital Period: 0.615 197a (224.701d)

End of podcast:

365 Days of Astronomy
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