How to increase the size of my photo?

I was lucky enough to get my best ever photo of a raptor in flight earlier this year.  There's a local competition I'd like to enter it into - the only problem is that they require all entries to be at least 1mb in size .......... mine is a magnificent 122kb!  Is it possible to increase the size without compromising the quality?  

I should mention that I have Photoshop Elements 14, which I hope will be capable of performing this miracle.