The "Local Hot Bubble" is an irregularly shaped low-density cavity in
 the ISM surrounding the sun. It is filled with a million degree hot
 plasma emitting soft X-rays.
 We have discovered a neutral dense filament located in the Local Hot
 Bubble. It has low kinetic temperatures, high space densities and is
 seen to cast a deep shadow in the ROSAT C-Band soft X-ray observations.
 The existence of neutral dense matter in the LHB is surprising in the
 first place. Either the filament formed recently in the LHB, or it did
 survive for a very long time; both explanations are a challenge to our
 understanding of the ISM.
 This part of the proposal addresses the question about the temperature
 and composition variations of the dust across the filament. As it is
 located in a hot plasma region we expect a temperature gradient and an
 increased number of small particles towards the cloud core. This
 filament is a unique object to study the influence of a hot
 surrounding on the dust and gas phase on a predominatly atomic
 hydrogen cloud. As the cloud is located in the vicinity of the sun
 this analysis will provide additional information on the
 radiation field in the local surrounding.