'Optimism and project preparation' - Essay to univ. of illinois-

please help me with grammatical stuff..and some word replacements too

NOTE: i'm mentioning my participation in an annual international contest as an extra curricular Activity!

In an essay of 300 words or less, choose one extracurricular activity, work experience or community service project from the list you provided on the application and explain why you initially chose it, why you continued with it, and how you benefited from it

One of the most defining and memorable moments in my life was my participation in the 2008 INTERNATIONAL SPACE SETTLEMENT DESIGN CONTEST sponsored by NASA. I had to propose a design for a space settlement by working on various aspects ranging from structure, operation, life support systems, transport and business development of the settlement. At the same time it had to be made accessible to a common man and not just scientists and astronauts.

I do believe that man has the desire to grow and expand; space is definitely what we can view as our next home. Another reason for my participation was, that the idea of a space settlement captivated me and I knew that I could use my creativity abilities along with my skills and passion about space as the fuel to outperform.

Though I came across this competition on the Internet just five days prior to its submission deadline of 31st March 2008, I never thought about it pessimistically and gave in my best for the project.

I worked all day and night not sparing time to do anything else but my project. It was the most challenging experience ever. On the day I posted this project I had a feeling immense satisfaction and fulfilment. I managed to bag an Honourable mention.

I learned a lot during the course of project preparation. Most importantly-the significance of optimism. I had to do a lot of research to prepare the project, during the course of which I learnt about survival in space, space technology and transport. I was amazed by the various ideas suggested for transport-one of them being the 'space elevator'. I comprehended that engineering is a field that enables one to use his creativity to its fullest.

well, it would look better if you combine the second and the third sentence to avoid repeating "we had to"... but than it would be too long sentence...

maybe

"...by NASA; My team's job was to propose a design for a space settlement. We had to..."

your last sentence on your 1st paragraph is kinda confusing//maybe rephrase it a bit?

first sentence on your second para; I'm having hard time understanding...so that is part of your reason that you participated?

I want to correct some of the phrases that sounds a bit akward but because I'm also an international student who aren't very good at grammar fixes I will let others give some advices...

good luck :)