Where to start? I want to be an astrophysicist....

[Kenneth DeMaio]

I want to be an astrophysicist, I'm only a sophomore in Hs. What books would you recommend to getting more into physics and astronomy to have a head start?

 

[Niladri Dan]

My question too...!

 

[PeroK]

You can always make a start learning Special Relativity, which is advanced from a conceptual point of view, but requires limited maths.

There's a free textbook here:

http://www.lightandmatter.com/sr/

The other option is to get ahead a bit in maths. The UK advanced "A" level maths (16-18 years olds) is online here:

http://www.examsolutions.net/

And, some college/university level maths is here:

tutorial.math.lamar.edu

It might be good to take a look to see how much of it makes sense.

 

[Niladri Dan]

For relativity you need to know multi variable calculus and tensor analysis...

 

[PeroK]

For relativity you need to know multi variable calculus and tensor analysis...

... that would be General Relativity, which is mathematically a different ball-game altogether.

 

[Dont Wanna]

Um..there's this thing called a "library"...where you go. They have books! Lots of em! And you can take them home- for FREE! (provided you bring them back in time)

OK, that was a bit mean. You asked an honest question, so let me back up..."where do I start?" Hmm, where do I start...other than the library...the possible answers to that question are literally endless, especially in the Internet Age. But here is a not-all-that-comprehensive list of things to look at/consider:

Step 0: Some inspiration- Watch & listen to James Burke in this final four minutes of the final 10th episode of Connections from 1978. (speaking of the Internet Age, he predicted it...40 years ago...!)
Step 1: Figure out an academic agenda for yourself in HS. What courses are u taking next year? Do you like math? Coz you'd better! And if you don't, you'd better learn to! And don't think you won't learn to...math isn't that hard, it just takes practice and has a learning curve, like pretty much everything else in life. Are you taking the most challenging classes you can handle? Or the easier stuff you know you can ace? Have u told your guidance counselor what you just told us in your post?
By the time i was a senior in HS, I already regretted not pushing myself to work harder as a Frosh/Sophomore. Come up with a plan for where u want to be, brain-wise, when u graduate...thats your homework for the summer. To help you in this:
Step 2: Dig online. Youtube has mountains of science videos. True, many are of just documentary, info-tainment value and you need to sift out the BS nonsense about aliens and conspiracies and prophecies and whatnot. But there is actual hard science in there, too. I'm a fan of the oldies-but-goodies, so the Mechanical Universe is a good place to start. Its basically a video documentary supplement to a basic first year college physics course. More than 50 half hour episodes, gets into nitty-gritty but is also entertaining, made in 1985 by Cal Tech physics professor David Goodstein. To get into a more hard-core, hands on learning experience (with ACTUAL homework) go to Khan Academy and https://www.learner.org/resources/browse.html. Both are free and go-at-your-own pace. KA is just step by step exercise work and Annenberg is for school teachers but has in-depth lessons in math and science (Mechanical Universe used to be one of them, but they discontinued it). For a contemporary up-to-date take, Bruce Betts of the Planetary Society (which you might consider joining) teaches a yearly online Intro to Astronomy course. To delve even deeper you can check out MOOCs for a current course at an actual university, but i would work your way up to that with the previously mentioned stuff, first. Which brings us to:
Step 3: Go to your local library...and ask. Say "hey, where's your astrophysics books?", and browse. You'll see Carl Sagan, Richard Feynman, Kip Thorne, Brian Greene, and the guy Eddie Redmayne played, Stephen Hawking, just to name a very few. Neil deGrasse-Tyson may be there, too...though not his new one, which you may be interested in, but u got to buy it, or ask for it for your birthday. And all of these people you will find something of, in some form or other on youtube.

That'll get you started. Go from there. Talk to your guidance counselor, that's what they're paid for. No ones going to do it for you...work hard, but don't burn yourself out.