it is possible through (ONLY) Internet Explorer's Javascript or VBScript ActiveXObject function. for instance, in javascript:
var ExcelApp=new ActiveXObject('Excel.Application');
ExcelApp.Workbooks.Open(location);
ExcelApp.Worksheets(index).Activate();
ExcelApp.Visible=true;
Where:
location - a string specifying the location of the workbook
index - the index of the worksheet in question, starting at 1