Not sure what the source for that "more millionaires than the UK" claim is. Acoording to the 2009 Merrill Lynch/Capgemini WWR, the standard reference for tracking that data, India currently has 84,000 millionaires, the UK 362,000. Far more relevant here though, India's purchasing-parity-adjusted GNI per capita--the measurement aid agencies use to determine development level--is only $2960, compared to the UK's $36,130. Fully one-third of the world's poor (i.e., those living below the $1.25/day international poverty line) live in India, where they comprise 42% of the population. (An additional 33% of Indians live on less than $2/day--meaning India actually has a greater proportion of people in that income category than sub-Saharan Africa does.) It is true that by some of the conventional measurements (definitely not GDP!), India's economy is about half again as large as the UK's, but considering that India's population is 19 times larger, that doesn't mean much.
As for the space program, India's had that for 40 years; it's nothing new, and like most other space programs, is valued as much for its capacity to jumpstart research and technology in indirectly related fields (India's satellite networks, for example) as for its symbolic nationalistic value. The Indian government has budgeted Rs. 386 crore (about $82 million/£50 million) for the next moon mission (which is scheduled for 2013, not 2009). As space programs go, it's hardly a lavish one; nonetheless, it's certainly always had its fierce critics within India, who blast it for the same reasons as gman. (Their nuclear program, not so much--consider who India's neighbors are and what kinds of weapons they have.)
The UK Department for International Development has comprehensive reports accounting for their spending in India on their website; it's pretty much all directed into education, healthcare, rural development, and urban poverty projects in 4 of India's poorest states. If I were a British citizen concerned about whatever proportion of my tax dollars goes to India via UKDID, I'd start by studying that.