Chemistry measurementsChemistry measurements

In-situ measurements of NO2 and tracers (like CH4 or N2O to identify the origin of the air masses)

Infra red Quantum Cascade Lasers (SPIRIT, lighter version of SPIRALE)

Technique of measurement

Remote sensing measurements using Moon and Sun as light sources (line of sights at least ten times smaller than for satellite instruments)

(lighter version of SALOMON)

SALOMON NO2 measurements

In-situ measurements: :

Accurate estimation of the concentration, but lower probability to cross a local enhancement

Remote sensing-measurements:

Higher probability to detect the enhancement but underestimation of the absolute values of the concentrations (“dilution” effect)

=> Need to combine the two techniques (by using the two instruments in the same or in different gondolas)

Strategy of measurementsStrategy of measurements

Simultaneous measurements from satellites and balloon of the regions that produce the TLE and TGF

Choice of a launching site:

“Safe” tropical region with possibility of CNES installation

Best probability of detection of TLE and TGF

TLE:TLE:

a)

b)

c) d)

Lightning

TGF:TGF:

Best solution :Best solution :

Launch from Kourou (at least for the first campaigns)

Launch during weak stratospheric winds in order to stay close to the launching site for about 10 days

Recovery:

- can we accept to lose the gondolas ?

- recovery in the sea ?

But 10 days of measurements is better than 10 flights of several hours …

Several gondolas: Risk of losing the payloads Different scientific objectives (TLE, TGF, chemistry)

1 campaign per 18 months during the lifetime of Taranis and/or ASIM ?

Main issues to be solved

Telemetry limitation

Needs of technical flights to test the long duration balloons and the new instruments

Project under construction

Project submitted to CNES in 2009

Discussions with ESA for the project in the frame of ASIM