NASA wants to know how much water had Venus

A week after launching MAVEN , a mission to investigate the atmosphere of Mars , NASA is preparing to do the same with Venus.

"It is appropriate that the dates of these two releases have been so close because both detailed study atmospheric losses Kelly - Fast , MAVEN program scientist and member of the Planetary Astronomy Program at NASA 's headquarters in Washington - . The VESPR observe Venus from above the absorbing atmosphere of the Earth , and travel to Mars MAVEN to a study of more duration. "

The VESPR is a system of two platforms, in which a Terrier- missile originally built to be a ground-based missile and later redesigned to support scientific missions combined , and a Black Brant sounding rocket Mk1 model with a telescope inside. The integration took place at the Wallops Flight Facility in Virginia NASA .

The experiments study the ultraviolet ( UV ) emitting atmosphere of Venus, and can provide much information about the history of water on the planet . Measures such as this can not be carried out using ground-based telescopes because our atmosphere absorbs most of the ultraviolet radiation before it reaches the ground.

Therefore, the sounding rocket will carry the telescope more than 110 miles above the surface of the Earth. By now the atmosphere is sufficiently thin to allow UV readings .

" Today, Venus has a very thin atmosphere , which contains very little water, but we believe that the planet , originally , was a valuable ocean water " qualifies John T. Clarke, principal investigator for the mission and a member of Boston University .

Scientists are still trying to determine whether water existed on the surface of Venus , or is only found in the upper layers of the atmosphere , where temperatures were cooler . If ever the surface temperature had remained below the boiling point for long enough, the rivers could have flowed across the planet , and even Venus could have had ice.

Hydrogen and deuterium
The key to solving much water at that time was Venus lies in knowing how much hydrogen and deuterium ( a heavier version of hydrogen) remains in the atmosphere . Both can be combined with oxygen to make water, both in the familial form of H2O and the rarest , consisting of deuterium and oxygen , called HDO (which also produces small amounts of D2O) .

The high intensity ultraviolet light from the sun has broken away nearly all water molecules that may be in the atmosphere of Venus. Being lighter components , normal hydrogen molecules escape into space more rapidly than do the heavier deuterium . Comparing the amount of deuterium in the atmosphere there now with the amount of hydrogen , researchers can estimate how much water Venus disappeared and how fast did this circumstance.

Initial estimates made ​​from data collected by the NASA Pioneer Venus spacecraft in 1978 and other observations indicated that Venus might have once had enough water to cover the entire globe with seven meters of liquid . But it turns out that the amounts of hydrogen and deuterium may vary at different heights of the Venusian atmosphere , which would change the calculations. To help address these concerns, the VESPR make specific measurements in the upper atmosphere .

VESPR instrumentation to observe Venus for eight minutes , and your data will be transmitted in real time, before the load returns safely to Earth by parachute . Later , it will try to load the instruments to be used in future expeditions .

Clarke and his team combine these measurements with observations of Venus made ​​recently with the Hubble Space Telescope NASA. The group is also working with Jean- Loup Bertaux, the French National Center for Scientific Research to study the planet using the UV instrument of Venus Express spacecraft of the European Space Agency