Hydrogen in the gaseous phase liquefies at �252.9 degrees Celsius. The liquid phase changes to the solid phase at �259.3 degrees Celsius. Note that both of the figures quoted are for one atmosphere pressure.
In addition, between �269 degrees Celsius and �272 degrees Celsius, Hydrogen exists in a specific crystalline form with unusual properties.
HWKE, Skreecheeboy is fortunate in having a very learned chemistry teacher. Following the work of McGrady et al in the University of New Brunswick, it has since been shown that it is possible to convert gaseous Hydrogen to solid Hydrogen without it undergoing the liquid phase using specialised methods. Certain research papers on this subject are available via Ingenta etc. for those with access to university library databases online via the usual methods. I recently read a fascinating paper awaiting publication on this very subject by a fellow scientist at a certain government research facility.
Doin�t believe everything you read in Wikipedia. Wikipedia is an anathema to all professional scientists the world over. The concept that an information source should be allowed to be freely editable by users to include fact and fiction alike reduces the credibility of the source at a stroke, problems freely acknowledged by Wikipedia�s founder, Jimmy Wales. Furthermore, it is to be noted that the article cited acknowledges that sources and references are missing. .
Incidentally, the figures I�ve quoted above come from Patnaik�s �Handbook of Inorganic Chemicals�, a standard reference source for chemists worldwide. Hawley�s Condensed Chemical Dictionary provides the similar figures.
Potterfan3, we use solid Hydrogen for a number of research purposes. However, even for bona fide users, solid Hydrogen requires specialised storage, transportation and handling methods.
It's simply not viable.