A big day for the ESA: Sentinel snaps and ExoMars brakes

If you're trying to sell something to the European Space Agency, today could be the day to move in and close the deal because there should be smiles all round after two missions achieved important milestones.

The most visible achievement is depicted above (here for mobile readers): the Italian port city of Brindisi, as photographed by the Sentinel-B satellite.

Sentinel-B only went aloft last week and is the second of two birds in the Copernicus Earth-observation mission. Publication of the first snap it's sent home is is lovely proof of concept for the satellite's ten-metres-per-pixel resolution and an important step in its three-month commissioning process. The ESA's announcement says the word “Brindisi” translates to English as “toast”, as in to toast an occasion with a drink. Your correspondent's ancient history lessons taught that the town was the port from which countless Roman soldiers set out to conquer points East, perhaps also an appropriate evocation for the first photo.

But we digress from the second piece of good news, which comes from Mars where the agency's ExoMars craft has been in orbit since October 19th, 2016. The agency says that in the first week of March the orbiter successfully tested its various instruments and they all checked out.

That's important because for the next year ExoMars is going to be busy lowering its orbit so it can get a really good sniff of Mars' atmosphere. To do so it will conduct a few burns to get closer to Mars' atmosphere and “repeatedly surf in and out of the atmosphere at closest approach, pulling down its furthest point over the course of the year.”

By March 2018, it's expected ExoMars will be in a pretty-much-round orbit, 400km above Mars. From there its atmosphere-analysing instruments will be able to take better readings as we quest for compounds like methane that would indicate biological processes are at work.

ExoMars' formal science program will commence in March 2018, so knowing its instruments are in good order now is good news as the mission starts to slow down. ®