Geopolitics has also become an obstacle. Last December, NASA
expressed interest in a Venera-D collaboration. Then Russia invaded Crimea and
NASA drew back from most joint operations.
funding for the Venera-D project, envisioning a long-duration Lander on the
surface of Venus, which could function 30 days. Speaking at the 5th
International Aerospace Congress in Moscow, on August 29, 2006, Deputy Chief of
the Federal Space Agency, Vitaly Davydov, listed Venera-D among high-priority
exploration projects to be given funds by the Russian government. However level
and timing of funding projected by the government would not enable the launch
the mission before 2016. As Mars landing return has been given a top priority
show a Russian focus. In 2012, the Indian space agency, ISRO, announced that a
Venus orbiter would be launched next year, but no details have emerged since
then. That leaves the Japanese space agency, JAXA. Its Akatsuki probe tried to
enter Venus orbit in 2010. Though it was unsuccessful, due to engine damage,
the craft is swinging back for another try.
Mars, meanwhile, enjoys
much greater popularity. Two spacecraft are en route, and at least four more
are set to launch in the next decade (see chart). Venus Express only exists
because ESA threw together spare parts from its Mars Express mission. The
difference in attitude to our two nearest planets is partly technological. On
the surface of sweltering Venus, robotic probes survive for no more than a few
hours. Even then, power is a problem. Other probes use solar panels, but thick
clouds makes this impossible on Venus. The cloud barrier might be a mental
block, too. “Imagining ourselves going there is easier on Mars. That’s a big
part of planet Venus ” says Grinspoon its atmosphere which make any mission easier given right deployment for example air-brakes.


Venus death dive to unlock secrets of Earth’s evil twin On
its final plunge, the Venus Express probe will fly deeper than ever before –but
a return mission could tell us more about climate change and alien life.
As with end of Venus Express as a blank have to say goodbye to Earth’s fiery twin. European spacecraft will start a series of dives into the hellish atmosphere of Venus, marking the beginning of the end for the only probe now orbiting the planet. The dives will take the craft, called Venus Express, deeper into the atmosphere than it has gone before, allowing it to record conditions in a largely unstudied region.
It will also be a test of the spacecraft’s endurance
as it drags itself through the planet’s thick air, which will provide valuable
data for future interplanetary missions. Venus Express may not survive the
month-long campaign of daredevil plunges. Even if it does, the craft will run
out of fuel later this year. "No dedicated probe is due to launch in the next
decade", and a damaged Japanese craft has just a slim chance of making it there
next year. But there is still so much to discover about our neglected
neighbour.
Better knowledge of Venus could help answer two of the most
important questions in modern science: how is Earth’s climate changing, and are
we alone in the universe? “Venus is so similar to Earth and yet so different,”
says project scientist HÃ¥kan Svedhem at the European Space Agency (ESA). “One
really needs to understand Venus to understand all terrestrial planets.” At
first glance, Venus seems nothing like Earth. It is shrouded in a haze of
carbon dioxide, with toxic sulphuric clouds and temperatures topping 450 °C.
Its surface is bone dry, and the air pressure is high enough to rupture the
hull of a submarine.
As with end of Venus Express as a blank have to say goodbye to Earth’s fiery twin. European spacecraft will start a series of dives into the hellish atmosphere of Venus, marking the beginning of the end for the only probe now orbiting the planet. The dives will take the craft, called Venus Express, deeper into the atmosphere than it has gone before, allowing it to record conditions in a largely unstudied region.



However, Venus is almost exactly the same size and mass as Earth, and is made from similar materials. It is thought to have started out with a water-rich atmosphere like Earth’s, which may even have made the surface briefly habitable. But Venus is closer to the sun and lacks a global magnetic field, which is what protects Earth from our star’s harshest rays. Geoffrey Landis at the NASA John Glenn Research Center in Cleveland, Ohio, is working on Venus-specific technology, including electronics that operate at high temperatures and a solar-powered plane that would direct a rover on the ground. Perhaps an ambitious rover mission is key to reigniting interest in Venus. “We’ve discovered how fascinating Mars is because we have been able to land on the surface and rove around,” says Landis. “If we could drive around on Venus, we would discover: wow, it is just as interesting as Mars.” Without this shield, young Venus was blasted by radiation that boiled away most of the water in its air, leaving dense carbon dioxide and triggering a runaway greenhouse effect.


Daring dives for its swansong almost like a battery scoop and out, Venus Express will perform
aerobraking, a way to reduce the speed of a spacecraft and so reduce its
altitude. This lets an orbiting probe get much closer to a planet’s surface and
study it in greater detail.
2015 Venus Express will take its first dip into the clouds, where it will record the effects of friction from the atmosphere. During a series of these dives until 11 July it will also take readings on the atmosphere’s density and composition. ESA has never attempted aerobraking before, so lessons from the Venus experiment will be valuable for future probes. For instance, the agency plans to use the technique when the Exo Mars satellite arrives at the Red Planet in 2017, says ESA’s Olivier Witasse. Learning more about could also be useful for human missions. A related manoeuvre, called aero capture, would help spacecraft land on Mars or return to Earth without needing prohibitively large landing rockets. “People think the hard part of space travel is going as fast as you can,” says Grinspoon.
“There is also the hard part of slowing down when you get places, because you need a big rocket for that or you just keep going.” Venus Express survives the ordeal, the plan is to take the probe back into a higher orbit and continue observations until its fuel runs out. Many questions will remain unanswered, including whether the planet is still volcanically active, and whether life could have thrived in the planet’s past.
However, neither NASA nor
ESA has plans for another dedicated Venus mission and other space
agencies hold out for only faint hope. Every child likes space reality, as for the past decade Russia has been talking about a follow-up. This is to mark the Soviet Union’s successful Venera series of probes from the 1960s and 70s. “It is not doing very well,” says Oreg Korablev in the Space Research Institute in Moscow. “The Russian programme was dominated by Phobos Grunt Martian lunar exploration which failed, with china on board it took a decade of a build, because of its return journey. Both nations missed out due to its many as complex failures and laps of calculations an nod with pre-run it became an over laden catastrophe.” The mission, known as Venera-D, is set for a 2024 launch at its earliest.
2015 Venus Express will take its first dip into the clouds, where it will record the effects of friction from the atmosphere. During a series of these dives until 11 July it will also take readings on the atmosphere’s density and composition. ESA has never attempted aerobraking before, so lessons from the Venus experiment will be valuable for future probes. For instance, the agency plans to use the technique when the Exo Mars satellite arrives at the Red Planet in 2017, says ESA’s Olivier Witasse. Learning more about could also be useful for human missions. A related manoeuvre, called aero capture, would help spacecraft land on Mars or return to Earth without needing prohibitively large landing rockets. “People think the hard part of space travel is going as fast as you can,” says Grinspoon.
“There is also the hard part of slowing down when you get places, because you need a big rocket for that or you just keep going.” Venus Express survives the ordeal, the plan is to take the probe back into a higher orbit and continue observations until its fuel runs out. Many questions will remain unanswered, including whether the planet is still volcanically active, and whether life could have thrived in the planet’s past.

agencies hold out for only faint hope. Every child likes space reality, as for the past decade Russia has been talking about a follow-up. This is to mark the Soviet Union’s successful Venera series of probes from the 1960s and 70s. “It is not doing very well,” says Oreg Korablev in the Space Research Institute in Moscow. “The Russian programme was dominated by Phobos Grunt Martian lunar exploration which failed, with china on board it took a decade of a build, because of its return journey. Both nations missed out due to its many as complex failures and laps of calculations an nod with pre-run it became an over laden catastrophe.” The mission, known as Venera-D, is set for a 2024 launch at its earliest.
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