Having reached Venus in 1990

Magellan spacecraft Archives

canada goose coats on sale In February of 2014, NASA Discovery Program asked for proposals for the their 13th mission. Last week, five semifinalist were selected from the original 27 submissions for further investigation and refinement. Of the possible missions that could be going up, two involve sending a robotic spacecraft to a planet that NASA has not been to in decades: Venus! canada goose coats on sale

The first is the DAVINCI spacecraft, which would study the chemical composition of Venus atmosphere. Meanwhile, the proposed VERITAS mission or The Venus Emissivity, Radio Science, InSAR, Topography, and Spectroscopy spacecraft would investigate the planet surface to determine just how much it has in common with Earth, and Canada Goose Online whether or not it was ever habitable.

canada goose In many respects, this mission would pick up where Magellan left off in the early 1990s. Having reached Venus in 1990, the Magellan spacecraft (otherwise known as the Venus https://www.canadagoosestorevip.com Radar Mapper) mapped nearly the entire surface with an S band Synthetic Aperture Radar (SAR) and microwave radiometer. From the data obtained, NASA scientists were able to make radar altimeter measurements of the planet topography. canada goose

Deployment of the Magellan spacecraft with the Inertial Upper Stage (IUS) booster during the STS 30 Atlantis flight. Credit: NASA

These measurements revolutionized our understanding of Venus canada goose clearance sale geology and the geophysical processes that have shaped the planet surface. In addition to revealing a young surface with canada goose uk black friday few impact craters, Magellan also showed evidence of volcanic activity and signs of plate tectonics.

However, the lack of finer resolution imagery and topography of the surface hampered efforts to answer definitively what role these forces have played in the formation and evolution of the surface. As a result, scientists have remained unclear as to what extent certain forces have shaped (and continue to shape) the surface of Venus.

Canada Goose Outlet With a suite of modern instruments, the VERITAS spacecraft would produce global, high Canada Goose Jackets resolution topography and Canada Goose Coats On Sale imaging of Venus’ surface and produce the first maps of deformation and global surface composition. These include an X canada goose store band radar configured as a single pass radar interferometer (known as VISAR) which would be coupled with a multispectral NIR emissivity mapping capability. Canada Goose Outlet

Canada Goose Parka Three dimensional canadian goose jacket simulation of Gula Mons captured by the Magellan Synthetic Aperture Radar (SAR) combined with radar altimetry. Credit: NASA/JPL Canada Goose Parka

Canada Goose sale Using these, the VERITAS canada goose uk outlet probe will be able to see through Venus’ thick clouds, map the surface at higher resolution than Magellan, and attempt to accomplish three major scientific goals: get a better understanding of Venus’ geologic evolution; determine what geologic processes are currently operating on Venus (including whether or not active volcanoes still exist); and find evidence for past or present water. Canada Goose sale

Suzanne Smrekar of NASA’s Jet Propulsion Laboratory (JPL) is the mission principal investigator, while the JPL would be responsible for managing the project. As she explained to Universe Today via email:

canada goose coats objectives are to reveal Venus geologic history, determine how active it is, and search for canada goose uk shop the fingerprints of past and present water. The overarching question is Earthlike is Venus? As more and more canada goose black friday sale exoplanets are discovered, this information is essential to predicting whether Earth sized planets are more likely to resemble Earth or Venus. Credit: NASA/JPL canada goose coats

buy canada goose jacket In many ways, VERITAS and DAVINCI represent a vindication for Venus scientists in the United States, canada goose factory sale who have not sent a probe to the planet since the Magellan orbiter mission ended in 1994. Since that time, efforts have been largely focused on Mars, where orbiters and landers have been looking for evidence of past and present water, and trying to piece together what buy canada goose jacket Mars atmosphere used to look like. buy canada goose jacket

cheap Canada Goose But with Discovery Mission 13 and its five semi finalists, the focus has now shifted onto Venus, near Earth objects, and a variety of asteroids. As John Grunsfeld, astronaut and associate administrator for NASA Science canada goose coats Mission Directorate in Washington, explained: cheap Canada Goose

canada goose clearance selected investigations have the potential to reveal much about the formation of our solar system and its dynamic processes. Dynamic and exciting missions like these hold promise to unravel the mysteries of our solar system and inspire future generations of explorers. It an incredible time for science, Canada Goose Parka and NASA is leading the way. investigation team will receive $3 million to conduct concept design studies and analyses. Canada Goose online After a detailed review and evaluation of the concept studies, NASA will make the final selections by September 2016 for continued development. This final mission (or missions) that are selected will launcd by 2020 at the canada goose coats on sale earliest. canada goose clearance

canada goose black friday sale As the morning star, the evening star, and the brightest natural object in the sky (after the Moon), human beings have been aware of Venus since time immemorial. Even though it would be many thousands of years before it canada goose outlet was recognized as being a planet, its has been a part of human culture since the beginning of recorded history. canada goose black friday sale

buy canada goose jacket cheap Because of this, the planet has played a vital role in the mythology and astrological systems of countless peoples. With the dawn of the modern age, interest in Venus has grown, and observations made about its position in the sky, changes in appearance, and similar characteristics to Earth have taught us much about our Solar System. buy canada goose jacket cheap

Size, Mass, and Orbit:

Canada Goose online Because of its similar size, mass, proximity to the Sun, and composition, Venus is often referred to as Earth planet With a mass of 4.86761024kg, a surface area of 4.60 x 108 km, and a volume of9.281011km3, Venus is 81.5% as massive as Earth, and has 90% of its surface area and 86.6% of its volume. Canada Goose online

Venus orbits the Sun at an average distance of about 0.72AU (108,000,000km/67,000,000mi) with almost no eccentricity. In fact, with its farthest orbit (aphelion) of 0.728 AU (108,939,000 km) and closest orbit (perihelion) of 0.718 AU (107,477,000 km), it has the most circular orbit of uk canada goose any planet in the Solar System.

canada goose clearance sale Size comparison of Venus and Earth. Credit: NASA/JPL/Magellan canada goose clearance sale

canada goose deals When Venus lies between Earth and the Sun, a position known as inferior conjunction, it makes the closest approach to Earth of any planet, at an average distance of 41millionkm (making it the closest planet to Earth). This takes place, on average, once every 584days. The planet completes an orbit around the Sun every 224.65days, meaning that a year on Venus is 61.5% as long as a year on Earth. canada goose deals

Unlike uk canada goose outlet most other planets in the Solar System, which rotate on their axes in an counter clockwise direction, Venus rotates clockwise (called rotation). It also rotates Canada Goose sale very slowly, taking 243Earthdays to complete a single rotation. Canada Goose Outlet This is not only the slowest rotation period of any planet, it also means that a sidereal day on Venus lasts longer than a Venusian year.

Composition and Surface Features:

Canada Goose Jackets Little direct information is available on the internal structure of Venus. However, based on its similarities in mass and density to Earth, scientists believe that they share a similar internal structure a core, mantle, and crust. Like that of Earth, the Venusian core is believed to be at least canada goose be partially liquid because the two planets have been cooling at about the same rate. Canada Goose Jackets

One difference between the two planets is the lack of evidence for plate tectonics, which could be due to its crust being too strong to subduct without water to make it less viscous. This results in reduced heat loss from the planet, preventing it from cooling and the possibility that internal heat is lost in periodic major resurfacing events. This is also suggested as a possible reason for why Venus has cheap canada goose uk no internally generated magnetic field.

The internal structure of Venus the crust (outer layer), the mantle (middle layer) and the core (yellow inner layer). Credit: Wikipedia Commons

canadian goose jacket Venus surface appears to have cheap Canada Goose been shaped by extensive volcanic activity. Venus also has several times as many volcanoes as Earth, and has 167 large volcanoes that are over 100km across. The presence of these volcanoes is due to the lack of plate tectonics, which results in an older, more preserved crust. Whereas Earth oceanic crust is subject to subduction at its plate boundaries, and is on average 100 million years old, the Venusian surface is estimated to be 300 600 million years of age. canadian goose jacket

There are indications that volcanic activity may be ongoing on Venus. Missions performed by the Soviet space program in 1970s and more recently by the European Space Agency have detected lightning storms in Venus atmosphere. Since Venus does not experience rainfall (except in the form of sulfuric acid), it has been theorized that the lightning is being caused by a volcanic eruption.

Other evidence is the periodic rise and fall of sulfur dioxide concentrations in the atmosphere, which could be the result of periodic, large volcanic eruptions. And finally, localized infrared hot spots (likely to be in the range of 800 1100 K) have appeared on the surface, which could represent lava freshly released by volcanic eruptions.