Further infrared observations in 2004 by the European Southern Observatory and the Gemini telescope give results consistent with mixtures of water ice and carbonaceous compounds, such as tholins.
Posteriores observación no infravermello feitas no 2004 polo Observatorio Europeo do Sur e polo telescopio Gemini que deron coma resultado a existencia dunha mestura de xeo de auga e compoñentes baseados no carbono, tales coma as tolinas.