The right hand image shows the brown dwarf in high contrast. An even greater challenge is to detect planets directly. My Montreal colleagues and I feel that our technique, particularly in its ability to defeat speckle noise, has great potential and plans are afoot to equip KIR with a dual imaging coronagraphic module. The left hand image is taken through the CH 4 filter - the right hand in the continuum. Judicious selection of contrast in SAO Image really makes the brown dwarf stand out on the right.
Astronomers are very good at digging weak signals out of hugely noisy backgrounds.
The CH 4 absorption bands 18 render the spectrum of a gas-giant quite distinct from the sparse solar spectrum of the parent star as can be seen in Figure 6. The solid lines are for an equivalent black-body. A conservative estimate of sensitivity suggests that with 100 nm spectral coverage near 1.6 micron on the CFHT and an hour's exposure per night, we could easily detect the spectrum of the secondary phase-sensitively over a single cycle of the 3.3 night orbit. Someone is bound to succeed with this soon. Just over a year ago, Williams, Kasting and Wade 19 made the provocative suggestion that extra-solar giant planets might have habitable moons if they lie in, or pass through, the habitable zone of the parent star.