"I read on an astrology web site that people who have birthdays from April 29th - May 5th should experience powerful changes this year since we are in a new Solar Return. What is a Solar Return, how often does it occur, and what is it's significance? (It also said Jupiter is in square to rebellious Uranus in our new Solar Return.)?!?"
Everyone experiences a Solar Return every year around their birthday. It literally is when the Sun in the sky comes to the exact degree it was at the moment we were born. It is a "return" to its original position.
The significance of the Solar Return is that it provides a chart that can be assessed in addition to your birth chart. I look at the Solar Return as an overlay of sorts, for example, I look at the Solar Return and consider it alongside the natal chart transits. The Solar Return is a chart for the coming year.
When looking at a Solar Return chart, we look to see what house the Sun, Mercury, Venus, etc. are in. This shows what the tendencies will be for the year just as the natal birth chart shows the tendencies of a person for the lifetime. We can often see if the focus will be on career, love, etc. I've noticed in my own charts that it's very obvious to detect busy years from quieter ones, years with lots of travel, years for working a lot, etc.
What I've found intriguing about the chart is that we can begin at the Ascendant and go backward through the houses to discover what month in the coming year will hold a particularly powerful influence.
One client recently had the moon (ruling emotions) in the 12th house (hidden, unconscious, events of the distant past) of her Solar Return chart. With that placement, she might experience more emotions than usual during the first month or so following her birthday.
She later reported that during that first month she had many "behind the scenes" emotional days, whereby very old griefs and past hurts came to the surface for her to work through. Much of this grief she thought she had already dealt with.
So it's endlessly interesting to me and I love that you took the time to get clarification.
In terms of Jupiter square Uranus for your Solar Return this year, I would want to see what houses these two are in. But Jupiter is in Sagittarius while Uranus is squaring from Pisces. When these two touch upon each other, you can experience sudden opportunities or an unbridled desire to escape any type of restraint or restriction on yourself.
For those born around the beginning of May, 2007 there might seem to be a rebellious streak in them this year, as changes are apt to be made without considering all of the consequences.
At any rate, I always see Uranus as upleveling and making changes for us, whether we like it or not, but for the better. Uranus takes us to a new place, freshens the scenery, and sometimes does it abruptly while all bystanders are looking on with their chins dropped at the audacity of it all.
Enjoy your wild ride this year!