ESA - Clean Space Programme logo. 25 September 2015 When a rocket is launched into space it crosses all layers of the atmosphere and interacts with them. How much impact does a launch have on the atmosphere and can we quantify the effect in such a way that we can take mitigation measures? These are only a few of the questions raised by the Clean Space AtILa (Atmospheric Impact of Launchers) project. Neil Murray explains: “It is difficult to use computer modelling to precisely monitor what happens when a rocket is launched as the size of the plume is far smaller than the scale of the climate models that we use to model the atmosphere”.
Picture perfect liftoff
Therefore two strategies were worked out to model the impact, one started from the size of the plume and this was allowed to develop over time and space to the size of the climate model and used as the boundary conditions of the climate model. Another strategy started from the size of the larger model and introduced sub-grid models which modelled the plume within the climate model grids. Both models gave surprisingly similar results. So far it has been thought that chlorine, which is converted from the oxidizer (ammonia perchlorate) in the solid booster fuel mixture, has had the main effect on ozone depletion in the immediate area where the plume is emitted.
Computations conducted at ONERA using the CEDRE code
The latest studies have shown that alumina particles, i.e., oxidised aluminium, which is also present in the solid rocket fuel, may also have a significant ozone depletion effect depending on the particle size. “If the particles are on the micrometer scale they would quickly fall out of the sky and have little impact on the atmosphere. However, the smaller the particles, the higher their combined surface area and the longer they remain suspended in the air, which means that their potential catalytic effect in ozone reduction could also be much higher.” Therefore it is imperative that quantitative data is collected to be able to accurately measure and predict the impact by mathematical models.
Computations conducted at ONERA using the CEDRE code
The first step towards quantitative data is the kick-off of an activity organised in cooperation with DLR whereby a solid rocket motor model in a wind tunnel will be used to simulate the evolution of particles in a representative rocket chamber and to then interpolate this to the conditions at launch. From these measurements accurate models will be developed for predicting the development of alumina particles under real launch conditions. So why not just use real launch data? “It is not that easy to make these measurements during a real launch and so far no data has been collected for European launchers. Up to now we have mainly been relying on data measured by NASA during launches in the 1990s, however, the representativeness of this data with respect to European launchers is questionable. This ultimately leaves us with the task of somehow collecting such flight data and it is something that we are discussing at length.“
Ariane 5 ECA V184 climbout
"Even when we are able to make real-time measurements during a launch it still is a large task to interpret this data correctly and extrapolate this to all launches, as daily changes in the atmosphere and the time of the launch are just a few parameters that severely influence the effect. Luckily we are working with some of Europe’s experts in climatology!” The AtILa project aims to understand the impact of launching its rockets into space by modelling the rocket plumes from their origin in the rocket chamber up to their impact on a global scale using climate models. This is one of the projects that ESA carries out under the Clean Space initiative which has carried out life cycle assessments for the space industry in order to monitor the effect of each space project on the environment. Implementing eco-design strategies into every phase of a space project is the ultimate aim of this initiative. ESA links: Life cycle assessment training at ESA: http://www.esa.int/Our_Activities/Space_Engineering_Technology/Clean_Space/Life_Cycle_Assessment_training_at_ESA Virtual rocket launches will probe atmospheric effects: http://www.esa.int/Our_Activities/Space_Engineering_Technology/Clean_Space/Virtual_rocket_launches_will_probe_atmospheric_effects Considering hydrazine-free satellite propulsion: http://www.esa.int/Our_Activities/Space_Engineering_Technology/Clean_Space/Considering_hydrazine-free_satellite_propulsion ‘Green’ satellite fuel designed to make space safer: http://www.esa.int/Our_Activities/Space_Engineering_Technology/Green_satellite_fuel_designed_to_make_space_safer About Clean Space: What is Clean Space?: http://www.esa.int/Our_Activities/Space_Engineering_Technology/Clean_Space/What_is_Clean_Space Why is it needed?: http://www.esa.int/Our_Activities/Space_Engineering_Technology/Clean_Space/Why_is_it_needed What are its objectives?: http://www.esa.int/Our_Activities/Space_Engineering_Technology/Clean_Space/What_are_its_objectives Images, Text, Credits: ESA/CNES/ARIANESPACE/Photo Optique Vidéo CSG/Service POV du CSG. Best regards, Orbiter.ch Full article
Trident is a remote-controlled, camera-equipped underwater drone – and it’s the fastest machine yet from underwater robotics startup OpenROV. It can go as fast as Michael Phelps.
The underwater drone can stream live video to a monitor during explorations and the team at OpenROV is currently exploring VR so those playing with one of these drones can feel like they are right there in the depths with their vehicle.
Check out the video here!
The asteroid Nemesis is named after a Greek goddess who wields an apple branch, lash and sword. She is know for setting the scales right and often identified with revenge. The asteroid is in play with today & tomorrow’s cosmic weather. Good time to ask yourself who, or what, is your worst enemy and what role you play in the dynamic. And maybe make some #apple #tarts too….,
G20 Governments collectively handed out $452bn in subsidies for fossil fuels in both 2013 and 2014 - four times the amount allocated globally for renewables.
(via Fossil fuels receive four times as many subsidies as renewables, report finds)
UAV Will Determine Best Locations for Wind Energy
Ifixit produce open repair guides for everything imaginable, in a variety of languages, and help sustain a global community of independent repairers who divert electronics from e-waste dumps and keep poor and marginalized people connected to their work, school and families.
The Ifixit repair kits are thoughtful, high-specification, low-cost toolkits designed to work on all modern gadgets, as well as traditional ones (for example, Ifixit manufacture their own drivers for Apple’s bizarre “pentalobe” screws, which Apple had instructed its Genius Bar staff to quietly swap in during routine repairs).
The big daddy of Ifixit kits is the $130 128-bit Universal Bit Kit, which comes in a handsome wooden case and is covered by Ifixit’s lifetime warranty.
But Ifixit makes smaller, more specialized kits, including theSmartphone Repair Kit, priced at $25, specifically aimed at the budgets of enterprising high-school students who want to start their own smartphone repair businesses, using Ifixit’s manuals.
http://boingboing.net/2015/12/02/ifixit-repair-kits-everything.html
10 reasons why cities hold the key to climate change and global health
Holy shit! The single reason Republicans have no right to exist is climate denial on behalf of energy companies.
Now a new filtering device, invented by a US teenager, could provide a cheap and easy way to purify water.
The renewable heavy metal filter, designed by 18-year-old Perry Alagappan, removes 99% of heavy metals from water that passes through it. The filter, built from graphene nanotubes, can be rinsed with a vinegar concentrate and reused. The highly concentrated waste can then be evaporated, leaving a deposit of pure metal that can be used in many different applications.
Alagappan, who was awarded the Stockholm Junior Water Prize at this year’sWorld Water Week, said the filter cost just $20 (£13) to make, up to five times less than existing reverse osmosis technology.
“I became interested in water purification when I visited my grandparents in India, and saw with my own eyes how electronic waste severely contaminated the environment,” said the recent high school graduate from Houston, Texas, on winning the prize.
Breathtaking Images of Underwater Life Captured by Freediving Photographers Alex Voyer and Alex Roubaud
A reliable way to make people believe in falsehoods is frequent repetition, because familiarity is not easily distinguished from truth.
Daniel Kahneman, Thinking, Fast and Slow