Okay, now, posting from where I can see my library....
Stuff by David Brin can be fun. If you want pushed Science, go for Earth. His short novel The Practice Effect explores a universe where the laws of thermodynamics are somewhat reversed. His two Uplift Trilogies (Sundiver, Startide Rising, The Uplift War and Brightness Reef, Infinity Shore, Heaven's Reach) are less rigorous, but chock full of ideas.
Other authors to look for include Greag Bear and Ben Bova, Gregory Benford, and Vernor Vinge.
You might also want to try Heart of the Comet (about an exploratory team that lands on a comet) by Gregory Benford and David Brin.
Shiva Descending is a good "big thing about to hit the Earth" book, by Greg Benford and William Rotsler.
If you like that one, also try The Hammer of God by Arther C Clarke. Similar subject matter to Shiva Descending.
Murasaki is a novel in six parts about a exploratory group on a planet where we find alien live. Authors include Poul Anderson, Greg Bear, Greg Benford, David Brin, Nancy Kress, Frederik Pohl, eidted by Robert Silverberg.