  The benchmark exoplanet GJ 1214b is one of the best studied transiting
planets in the transition zone between rocky Earth-sized planets and gas or ice
giants. This class of super-Earth/mini-Neptune planets is unknown in our Solar
System, yet is one of the most frequently detected classes of exoplanets.
Understanding the transition from rocky to gaseous planets is a crucial step in
the exploration of extrasolar planetary systems, in particular with regard to
the potential habitability of this class of planets. GJ 1214b has already been
studied in detail from various platforms at many different wavelengths. Our
airborne observations with SOFIA add information in the Paschen-alpha cont. 1.9
micron infrared wavelength band, which is not accessible by any other current
ground- or space-based instrument due to telluric absorption or limited
spectral coverage. We used FLIPO and FPI+ on SOFIA to comprehensively analyse
the transmission signal of the possible water-world GJ 1214b through
photometric observations during transit in three optical and one infrared
channels. We present four simultaneous light curves and corresponding transit
depths in three optical and one infrared channel, which we compare to previous
observations and state-of-the-art synthetic atmospheric models of GJ 1214b. The
final precision in transit depth is between 1.5 and 2.5 times the theoretical
photon noise limit, not sensitive enough to constrain the theoretical models
any better than previous observations. This is the first exoplanet observation
with SOFIA that uses its full set of instruments available to exoplanet
spectrophotometry. Therefore we use these results to evaluate SOFIA's potential
in this field and suggest future improvements.
