The Soviet Union has sent more than a dozen spacecraft to Venus called Venera. Many have succeeded and have passed through the Venus atmosphere but after 20 to 120 minutes, they were crushed. While rovers are exploring the planet Mars, why do we not know much of Venus after so many attempts? Many scientists have dreamed about overcoming Venus’s harsh atmosphere in order to explore the surface of Venus.
Venus is known as Earth’s “sister planet”, but it’s atmosphere is composed mostly of carbon dioxide.This causes a greenhouse effect and the temperature on the surface of Venus is 460 degrees Celsius on average (860 degrees fahrenheit). This temperature is the same day and night, in the equator and poles. Because the temperature is so hot, this causes the probe or spacecraft to become too hot and overheat.
Above: Venus atmosphere is thicker than Earth’s, but its made out of different components. This graph shows the molecules in each planet’s atmosphere. While Venus atmosphere majority is carbon dioxide (CO2), Earth’s atmosphere majority is nitrogen (N2), but Venus also has a big amount of nitrogen (N2) in its atmosphere. While Earth is different from Venus, the graph shows that Mars shares the same atmospheric element: CO2.
The pressure from the atmosphere on the surface of Venus is also high. The pressure of the Venus atmosphere causes the probes to slow down making them less likely to pass through the whole atmosphere onto the surface of Venus. There have been many spacecrafts and probes that the Soviet Union sent to Venus in the 1960’s in order to explore the surface that either lost contact, were destroyed while entering the atmosphere, or were lost after their batteries died while going slowly through the atmosphere.
Also, the pressure of the atmosphere is so high that it crushes what goes into its atmosphere. This is how many probes and spacecrafts have failed and lost. While Earth’s atmosphere pressure is l bar at sea level, Venus atmosphere is 92 bars on the surface. In other words, Venus atmosphere is 92 times with more pressure than Earth.
Above: This graph shows the pressure of Venus atmosphere. The deeper you go into the atmosphere (meaning lower altitude), the more pressure you are exposed to.
The Surface and Atmosphere Geochemical Explorer (SAGE) mission to Venus is meant to overcome all the obstacles that previous spacecrafts had and explore the surface of Venus. This is a probe that is made in the United States by NASA, but the mission has not been fully funded. SAGE is a proposed mission that will hopefully help people understand what Venus looks like. This probe is only meant to survive about 3 hours on Venus and land on a volcano. SAGE is shaped as a sphere in order to not be crushed by the atmosphere. From the outside, it will look like a giant ball bearing. On the inside, the core that is made out of titanium and there will be cameras, spectrometers, and other instruments that will help explore Venus. SAGE will not have wheels, like the Mars probes, because Venus surface is filled with volcanoes, and it is really soft with really hard rocks that can break tools that can be used by the probes. Because of Venus high temperature, SAGE will have special insulation made out of lithium nitrate to protect the instruments.
Despite Venus’ harsh atmosphere, most of the probes and spacecrafts that were sent to Venus have not succeeded. The Soviet Union attempts on finding information about Venus by sending probes has helped improve future missions, like SAGE proposed mission. Maybe one day the mysterious of Venus will be revealed!