CH3OH in the HD100546 disk

When considering potential habitability, complex organic molecules are of relevance, key among which is methanol (CH_3_OH). Methanol primarily forms at low temperatures via the hydrogenation of CO ice on the surface of icy dust grains and is a necessary basis for the formation of more complex species such as amino acids and proteins.

We report the detection of CH_3_OH in a disk around a young, luminous A-type star, HD 100546. This disk is warm and therefore does not host an abundant reservoir of CO ice. We argue that the CH_3_OH cannot form in situ, and hence this disk has probably inherited complex-organic-molecule-rich ice from an earlier cold dark cloud phase.