European Space Agency Flickr Update


African mosaic
18-05-2016 02:07 PM CEST

europeanspaceagency posted a photo:

African mosaic

Using almost 7000 images captured by the Sentinel-2A satellite, this mosaic offers a cloud-free view of the African continent – about 20% of the total land area in the world. The majority of these separate images were taken between December 2015 and April 2016, totalling 32 TB of data. Thanks to Sentinel-2A’s 290 km-wide swath and 10-day revisit at the equator, the chance of imaging Earth’s surface when the skies are clear is relatively high. Nevertheless, being able to capture the Tropics cloud-free over the five months is remarkable.

Presented at the recent Living Planet Symposium in Prague, Czech Republic, this is the first mosaic of Africa generated through ESA’s Climate Change Initiative Land Cover project.

Launched in June 2015, Sentinel-2A carries a novel multispectral imager to provide information that is not only used to map changes in land cover, but is also used to improve agricultural practices, to monitor the world’s forests and to detect pollution in lakes and coastal waters.

Sentinel-2A’s identical twin, Sentinel-2B, is due to be launched in 2017. As a constellation, the two satellites will orbit 180° apart. Along with their wide swaths, this will allow Earth’s main land surfaces, large islands, as well as inland and coastal waters to be covered every five days. This will further improve the probability of gaining a cloud-free look at a particular location.

Credit: Contains modified Copernicus Sentinel data (2016), processed by Brockmann Consult/ Université catholique de Louvain as part of ESA’s Climate Change Initiative Land Cover project

Lego ExoMars 2020 model
18-05-2016 02:07 PM CEST

europeanspaceagency posted a photo:

Lego ExoMars 2020 model

This Lego model of Europe’s ExoMars 2020 rover on its lander was not built solely for fun – but is actually a tool, being used by robotics engineers in the midst of a major ‘egress’ test campaign.

Making a safe landing on Mars will be key to the success of Europe’s turn-of-the-decade mobile Mars mission. Then comes the next most important step: to successfully drive the wheeled rover from the top of its lander, otherwise known as egress.

The biggest decision of all will be which direction to drive – forwards or backwards – based on the limited data that operators have to hand. The lander will have two sets of tracks for the rover to descend in case one side is blocked, for instance by rocks (one also reproduced here in Lego).

To build up experience of egress and remote rover operations, ESA’s Automation and Robotics section together with ESOC’s Advance Mission Concepts section are conducting a long-distance test campaign in collaboration with the French space agency CNES. The ExoMars project team is monitoring the ongoing activities.

A half-scale rover on a mock-up lander has been placed in the outdoor 80 x 50 m ‘Mars Yard’ at CNES Toulouse. An operations team based a thousand kilometres away at ESA’s ESTEC technical centre in the Netherlands has first to egress the rover, then move it further across the simulated Marscape to explore and accomplish various tasks.

Across a series of tests that continue throughout this week, the ESTEC team has no knowledge of the lander’s precise placing but must work with the limited camera views and sensor data the rover and lander sends back to them, with results received and telecommands sent during a limited set of communication passes.

The Lego model lets the engineers easily visualise and communicate complicated telemetry data.

This campaign follows on from a previous egress campaign that took place last autumn.

Credit: ESA–G. Porter

You are subscribed to Flickr for European Space Agency.

Having trouble viewing this email? View it as a Web page.



Trage deine Daten unten ein oder klicke ein Icon um dich einzuloggen:

Du kommentierst mit Deinem Abmelden /  Ändern )

Google+ Foto

Du kommentierst mit Deinem Google+-Konto. Abmelden /  Ändern )


Du kommentierst mit Deinem Twitter-Konto. Abmelden /  Ändern )


Du kommentierst mit Deinem Facebook-Konto. Abmelden /  Ändern )


Verbinde mit %s