By Kanchana Chakravarty

June 3 (Reuters) - SpaceX SPCX.O will disrupt the $1.6 trillion U.S. communications industry as the Elon Musk-led company's satellite broadband unit Starlink expands, Oppenheimer said in a note on Wednesday, adding that legacy broadband providers like AT&T T.N may be most at risk.

The brokerage raised its estimate for 2035 space revenue to $800 billion from $500 billion earlier, ahead of the company's highly anticipated IPO this month.

• The expansion of Starlink is expected to further pressure cable firms, which are already losing subscribers.

• Oppenheimer said companies such as AT&T, Verizon Communications VZ.N and T-Mobile TMUS.O could see faster declines in subscribers and revenue going forward.

• The brokerage expects Starlink to "entrench itself in many critical applications, reducing churn and increasing pricing power."

• Oppenheimer raised its 2030 estimates for U.S. broadband subscribers to 15 million from 10 million earlier.

• SpaceX's rise could also tap into the half-a-trillion-dollar handset market as the company aims to replace smartphones, Oppenheimer said.

• "Should SpaceX execute on its mission...it will be the modern-day East India Company of space, controlling routes, infrastructure, and commerce of an entire frontier and giving it a quasi-sovereign reach, far beyond that of any ordinary corporation," Oppenheimer said.

• The company is set to debut on the Nasdaq on June 12 and is aiming to reach a $1.75 trillion valuation in the IPO, Reuters has reported.

• SpaceX's valuation is grounded in Starlink, which has over 10 million subscribers, and a launch business that analysts and investors say has transformed access to orbit.