SpaceX will launch an advanced GPS satellite for the US Space Force tonight. Here's how to watch.

Update for 9:57 p.m. EDT, Oct. 2: The SpaceX Falcon 9 rocket carrying the GPS III SV04 navigation satellite for the U.S. Space Force suffered an abort just two seconds before tonight's liftoff. A new launch date will be determined once the cause of the abort is identified and addressed. 

CAPE CANAVERAL, Fla. — A SpaceX Falcon 9 rocket  will launch an upgraded global positioning satellite (GPS) into orbit for the U.S. Space Force today (Sept. 30) and you can watch it live online. 

The flight — the 17th launch this year for SpaceX and its workhorse Falcon 9 rocket — is scheduled to blast off from Space Launch Complex 40 at Cape Canaveral Air Force Station in Florida at 9:55 p.m. (2155 GMT). The rocket is carrying the GPS III SV04 satellite for the Space Force.

You can watch the launch live here and on the homepage, courtesy of SpaceX, beginning about 15 minutes before liftoff. You'll also be able to watch the launch directly from SpaceX here

Related: The U.S. GPS satellite network explained 

If all goes as planned today, this will be the fourth launch of an upgraded next-generation GPS III satellite. Two have launched on different Falcon 9 rockets, the first launched in December 2018 and the third on June 30 of this year. The second GPS II satellite launched atop the very last Delta IV Medium rocket in August 2019. SpaceX has also secured the next few launches after this one as the military works to upgrade the aging network.

Built by Lockheed Martin in Colorado, these upgraded Global Positioning Satellites (or GPS) are some of the most sophisticated satellites ever made. They boast anti-jamming capabilities that are eight times more robust than previous iterations, and are equipped with more powerful signals for increased accuracy. 

Today's launch features the 4th in a series of 10 upgraded GPS III satellites for the military that will join the current constellation of satellites already in orbit. They will help provide positioning, navigation, and timing services for more than four billion users worldwide.

A SpaceX Falcon 9 rocket (left) carrying the GPS III SV04 navigation satellite for the U.S. military stands atop Space Launch Complex 40 at the Cape Canaveral Air Force Station in Florida. Another Falcon 9 carrying 60 Starlink internet satellites can be seen in the background at right at NASA's Pad 39A of the Kennedy Space Center. (Image credit: SpaceX)

Last week, Space Force announced that  the U.S. military has granted SpaceX permission to fly national security payloads on previously flown rockets. This follows on the heels of another recent decision to allow SpaceX to recover the rocket's first stage used on national security missions — something that was previously not allowed. 

SpaceX will launch the next two GPS missions — GPS III-SV05 and GPS III-SV06 —on veteran Falcon 9 first stages. The rockets flown on those two missions will also subsequently land back on Earth after their work is done, and are scheduled to launch sometime next year.

However,  today's mission will use a shiny new Falcon 9 booster, known as B1062 to SpaceX. It's rare to see a new Falcon 9 perched atop the launch pad these days, as the company has been relying on its fleet of veteran fliers to launch the vast majority of its missions. For today's flight, B1062 will carry an advanced global positioning satellite into orbit to replace an aging predecessor that was launched 20 years ago. 

Related: China launches final Beidou satellite for GPS-like navigation system

Today's flight will mark the 94th launch of a Falcon 9 rocket and the 61nd first stage recovery. SpaceX's drone ship Of Course I Still Love You is positioned out in the Atlantic Ocean, awaiting its planned recovery attempt. Approximately nine minutes after liftoff, the rocket's first stage is expected to touch down on the deck of the massive ship. 

The company's other drone ship, Just Read the Instructions is also hanging out in the Atlantic, waiting on its upcoming landing attempt, marking a rare occasion where both drone ships are being used simultaneously. Just Read the Instructions is SpaceX's newest drone ship and transferred to the East Coast earlier this year, after receiving a host of new upgrades. 

Today's launch comes just one day after SpaceX had to stand down from its 13th Starlink mission after a last-second abort. That flight was to blast off from nearby Pad 39A at NASA’s Kennedy Space Center. However, that mission has been plagued by a series of delays, mainly due to poor weather conditions at the launch and landing sites. 

SpaceX's two fairing catchers, GO Ms. Tree and GO Ms. Chief, are stationed out in the recovery zone. It's unclear if SpaceX will attempt to catch the fairings as they fall back to Earth, or if they will just scoop them up after they land in the water. (Whether or not a catch is attempted depends on a number of factors including weather and sea states at the recovery zone.)

The company has been successful in its attempts to reuse more of the rocket, even reusing several fairings on multiple missions. The rocket's nose cone, also known as a payload fairing, accounts for approximately 10% of the cost of the rocket. By reusing them, SpaceX has said it could save as much as $6 million per flight. 

Following several weather-related launch scrubs this week, the forecast for today's launch looks promising, as weather officials with the 45th Space Wing have predicted a 70% chance of favorable conditions at liftoff. According to weather officials, the main concern is the potential formation of thick clouds, which have the potential for producing lightning.

Tonight's launch may also come less than 30 minutes after another launch from NASA's Wallops Flight Facility on Wallops Island, Virginia. That mission will launch a Northrop Grumman Antares rocket carrying the Cygnus NG-14 cargo ship to the International Space Station for NASA. The spacecraft, which suffered a launch abort late Thursday, is carrying nearly 4 tons of supplies for the station and will only launch if Northrop Grumman has pinpointed and solved the glitch that caused the abort.

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Amy Thompson
Contributing Writer

Amy Thompson is a Florida-based space and science journalist, who joined as a contributing writer in 2015. She's passionate about all things space and is a huge science and science-fiction geek. Star Wars is her favorite fandom, with that sassy little droid, R2D2 being her favorite. She studied science at the University of Florida, earning a degree in microbiology. Her work has also been published in Newsweek, VICE, Smithsonian, and many more. Now she chases rockets, writing about launches, commercial space, space station science, and everything in between.