ASTROCHEMISTRY

1. Provide, at approximately 10 AU resolution, images of the chemical gradients in protostellar nebulae for nearby star-forming regions (e.g., in Taurus and Ophiuchus).

2. Obtain arcsecond-resolution mosaiced images of molecular abundances throughout GMC complexes; study the changes induced by fragmentation/condensation.

3. Yield the spatial variation of dissociative shock chemistry in outflow sources.

4. Enable study of photochemical processes via spectral-line images of circumstellar shells.

5. Probe dust formation and destruction via emission-line images of the refractory molecules that mark dust catalysis and spallation.

6. Provide high-resolution data revealing processes connected with low-temperature chemistry (deuteration and grain-mantle processing) in the cores of dense molecular clouds.