10-05-2016 03:32 PM CEST
europeanspaceagency posted a photo:
Scheduled for launch in November, ESA astronaut Thomas Pesquet is travelling the world preparing for his six-month adventure on the International Space Station. At NASA’s Johnson Space Center, in Houston, USA, Thomas is putting his spacesuit to the ultimate test on Earth: all the air is pumped out from the Space Station Airlock Test Article to create a vacuum like he would encounter in outer space.
Though Thomas has no spacewalk planned for his Proxima mission, all astronauts who live on the International Space Station are trained for spacewalks in case they need to head outside.
Thomas will be launched into space together with NASA’s Peggy Whitson and cosmonaut Oleg Novitskiy. The trio will soon be training in Russia and will support their colleagues on the next launch to the Space Station in June.
See more photos on Thomas’ Flickr page and follow his training and spaceflight first-hand on social media: thomaspesquet.esa.int
Credit: NASA-Bill Stafford
Sea-level variations from Sentinel-3A
10-05-2016 11:36 AM CEST
europeanspaceagency posted a photo:
Presented this week at ESA’s Living Planet Symposium in the Czech Republic, this new map shows a month of ‘sea-level anomaly’ measurements from Sentinel-3A. The satellite has only been in orbit since 16 February 2016 and is therefore still being commissioned for service. Nevertheless, measurements made by its radar altimeter between 3 March and 2 April have been used to create this map, which shows differences in sea-surface height compared to the mean.
Sea-level anomaly is the most basic altimeter data product. Red (positive) areas show where the sea surface is higher than the reference sea level and blue (negative) areas show where it is lower.
Positive anomalies are associated with warmer waters and a deeper ‘thermocline’ and negative anomalies are associated with cooler waters and a shallower ‘thermocline’ – the transition layer between warmer mixed water at the ocean’s surface and cooler deep water below.
The plot at the base of the sea-level anomaly map shows the normalised distribution of data, indicating a global mean of 7 cm and a standard deviation of 11 cm.
Using local sea-level variations measured by Sentinel-3’s altimeter and comparing them to a reference level, major ocean currents can be computed and mapped. Mesoscale eddy systems are clearly shown on the map as more intense blue and red patterns – effectively local hills and valleys in the sea surface. These are associated with the strong western boundary currents of the Gulf Stream in the North Atlantic, the Brazil current confluence with the Falklands current in the southeast Atlantic, the Benguela current off South Africa and the Kurishio current east of Japan.
Strong positive variability is also seen in the equatorial Pacific Ocean associated with oceanic tropical instability waves generated by instabilities within the equatorial currents themselves.
The Sentinel-3A radar altimeter will also measure significant wave height and provide estimates of surface wind speeds over the ocean, which is important information for ocean and wave forecasting systems operated by the Copernicus Marine Environmental Monitoring Service.
The radar altimeter data in this map were processed using France’s CNES space agency’s processing prototype (S3PP), with ESA level-0 data as input. A wet tropospheric correction was derived from European Centre for Medium-Range Weather Forecasts’ models.
Credit: contains modified Copernicus Sentinel data (2016), processed by ESA and CNES
You are subscribed to Flickr for European Space Agency.
Having trouble viewing this email? View it as a Web page.