* Futures lower: Dow 70 pts, S&P 8 pts, Nasdaq 12.5 pts
By Sruthi Shankar
Sept 5 (Reuters) - U.S. stock index futures were lower on Tuesday after North Korea conducted its most powerful nuclear test over the weekend, rattling investor sentiment.
* North Korea conducted its sixth nuclear test on Sunday, which it said was of an advanced hydrogen bomb for a long-range missile, marking a dramatic escalation of the regime's stand-off with the United States and its allies.
* The United States blamed North Korea's trading partners on Monday of aiding its nuclear ambitions and the White House declared that "all options to address the North Korean threat are on the table."
* However, equity markets recently have been able to withstand geopolitical events surrounding North Korea, with initial losses erased relatively quickly.
* September is typically the worst month in the year for stocks, with the S&P falling 0.5 percent on average. This September could be particularly nail-biting as Wall Street may face a rough ride if there is a showdown in Washington over the U.S. budget and the federal debt ceiling.
* Wall Street gained modestly on Friday as a tepid U.S. jobs report kept expectations muted for another interest rate hike this year, while investors kicked off a typically dour month for stocks on a positive note.
* The S&P 500 hovered near all-time highs as major stock indexes marked gains for a second straight week. The Nasdaq tallied a record closing high after minting its best week of the year.
* Equity markets were closed on Monday for Labor Day holiday.
* Economic data in the day include a report from the Commerce Department that will likely show that factory goods orders fell 3.3 percent in July, compared with a rise of 3.0 percent in the previous month. The data is due at 10:00 a.m. ET (1400 GMT)
* Federal Reserve's Minneapolis Chief Neel Kashkari and Dallas Fed head Robert Kaplan are expected to speak at different events later in the day.
* Fed Board Governor Lael Brainard will also speak on the economic outlook and monetary policy in New York.
* Shares of United Technologies were down 3.83 percent in premarket trading after the company struck a $30 billion deal to buy avionics and interiors maker Rockwell Collins. Rockwell shares were up 0.87 percent.
Futures snapshot at 7:01 a.m. ET:
* Dow e-minis were down 70 points, or 0.32 percent, with 46,185 contracts changing hands.
* S&P 500 e-minis were down 8 points, or 0.32 percent, with 325,331 contracts traded.
* Nasdaq 100 e-minis were down 12.5 points, or 0.21 percent, on volume of 78,790 contracts. (Reporting by Sruthi Shankar in Bengaluru; Editing by Anil D'Silva)