Gravity for the loss
12-06-2018 06:21 PM CEST
europeanspaceagency posted a photo:
Space agencies of Europe, assemble!
Last week, ESA, the German Aerospace Center (DLR) and French space agency CNES joined forces to run a special parabolic flight campaign entirely dedicated to life science experiments. Between 4 and 7 June, eight experiments were run in three different levels of partial gravity, another first for a parabolic flight campaign.
During our more common zero-gravity parabolic flights, research teams are subjected to 20-second bursts of weightlessness during which they run experiments ranging from life sciences, to technology demonstrations, to material physics. Results offer an indication of how various mechanisms work without gravity and are compared to results on the ground. But what happens at varying degrees of weightlessness?
To help fill in the graph, scientists were offered a unique opportunity to run experiments at one-quarter, one-half, and three-quarters gravity. The aim is to better understand biological dependence on gravity. Ultimately, if humans are to embark on long-term spaceflight and live on the Moon and Mars, we need to determine the levels of gravity in which humans can live and work.
One experiment investigated the effects of partial gravity on brain function. Previous studies have shown that short exposure to microgravity increased neurocognitive functions due to increased blood flow to the brain. However, longer-term spaceflight, in which increased blood flow to the brain is more permanent, showed negative effects on cognition. In this campaign, studying the phenomenon in partial gravity is helping scientists better understand where we draw the line for optimal performance.
Another team subjected baby plant roots to doses of partial gravity and monitored root growth using lasers to investigate how the roots manage to stay “grounded” in the absence of gravity. We know plants adapt to weightlessness rather quickly, but researchers still need a clearer picture of what’s happening on a cellular level. Extra-terrestrial farming is vital to human survival off-planet, and adapting agriculture to altered gravity is an important step to making this possible. For a full list of experiments, see here.
Parabolic flights are one of a few ways to recreate microgravity conditions on Earth, but how is this achieved? The A310 Zero-G aircraft, operated by Novespace in Bordeaux, France, repeatedly performs a special manoeuvre. After pulling up sharply to 50 degrees, the pilots reduce the thrust and pitch of the airplane to cancel air-drag and lift. This places the plane on a parabolic flight path, exactly as if it has been thrown upwards and released. It then essentially falls over the top of the parabola, creating 20 seconds of 0g. When it reaches 50 degrees nose-down, the plane then pulls out of the descent to normal flight.
To achieve partial gravity, the angle at which the plane pulls up and pulls out is shallower, and the pilots carefully cancel out only part of the lift. This creates about 25 seconds of one-quarter gravity, or 35 seconds of half-gravity, or 50 seconds of three-quarters gravity. The manoeuvre is performed every three minutes for a total of 31 times per flight. Watch a tour of the Zero-G aircraft here.
In addition to this unique collaboration between ESA, DLR, and CNES, the partial gravity parabolic flight campaign also featured a special guest experiment by NASA and pilot-turned-ESA-astronaut Thomas Pesquet.
„It was a real privilege to work on this unique campaign, not only because of the constructive collaboration with my colleagues from DLR and CNES, but also to provide such an interesting suite of experiments with rare and much-needed data,” said Neil Melville, Coordinator of Parabolic flight and Drop Tower campaigns. He is pictured on the left, alongside Katrin Stang of DLR and Sébastien Rouquette of CNES)
“We are certainly looking forward to the results the science teams will publish once their analyses are completed, and hope to perform a similar campaign in the future.“
ESA conducts 0g parabolic flight campaigns twice per year for microgravity research. Learn more here.
Hand-sewn insulation blankets
12-06-2018 11:11 AM CEST
europeanspaceagency posted a photo:
One of the main activities in recent weeks for the BepiColombo team at Europe’s Spaceport in Kourou has been the installation of multi-layered insulation foils and sewing of high-temperature blankets on the Mercury Planetary Orbiter.
The insulation is to protect the spacecraft from the extreme thermal conditions that will be experienced in Mercury orbit.
While conventional multi-layered insulation appears gold-coloured, the upper layer of the module’s striking white high-temperature blanket provides the focus of this image.
The white blankets are made from quartz fibres. Because the fabric is not electrically conductive, to control the build-up of electrostatic charge on the surface of the spacecraft, conducting threads have been woven through the outer layer every 10 cm. The edges of the outer blanket are hand-sewn together once installed on the module, as seen in this image.
The face of the spacecraft the engineer is working on is the panel that will always look at Mercury’s surface and as such many of the science instruments are focused here. This includes the orbiter’s cameras and spectrometers, a laser altimeter and particle analyser.
The panel also has fixtures to connect the module to the Transfer Module during the cruise to Mercury.
The face of the spacecraft pointing to the left in this orientation is the spacecraft radiator, which will eventually be fitted with ‘fins’ designed to reflect heat directionally, allowing the spacecraft to fly at low altitude over the hot surface of the planet. Heat generated by spacecraft subsystems and payload components, as well as heat that comes from the Sun and Mercury and ‘leaks’ through the blankets into the spacecraft, will be conducted to the radiator by heat pipes and ultimately radiated into space.
The oval shapes correlate to star trackers, used for navigation, while a spectrometer is connected with ground support equipment towards the top. At the back of this face, the magnetometer boom can be seen folded against the spacecraft – it has now also been fitted with multi-layered insulation.
For more images of the launch preparations at Kourou visit the BepiColombo image gallery.
Credits: ESA–B. Guillaume