Behind the Launch of Jupiter 3, the World’s Largest Comms Satellite

August 03, 2023 by Aaron Carman

On its way to geosynchronous orbit, the heaviest commercial satellite offers unprecedented coverage thanks to its unique design.

Last week, Hughes Network Systems, an EchoStar company, launched its Jupiter 3 satellite (also known as EchoStar XXIV) into geosynchronous orbit with the goal of extending internet coverage beyond land-based transmission. Using SpaceX’s Falcon Heavy rocket platform, the massive Hughes satellite is built to improve connectivity in rural areas in a method similar to SpaceX’s StarLink.


The Jupiter 3 satellite

The Jupiter 3 satellite, shown before being sent to Cape Canaveral, is roughly the size of a school bus when folded and expands to be larger than a commercial airliner. Image used courtesy of Hughes

The Jupiter 3 satellite weighs just over 20,000 pounds, making it one of the largest commercial satellites to ever be launched. Although this weight demands the utmost propulsion power to launch, Jupiter 3's size is necessary for the satellite to achieve its desired performance.

This article takes a closer look at the technology inside the school bus-sized satellite and gives readers a sense of the engineering effort used to design and launch the Jupiter 3. 


Multi-beam Connectivity

Hughes designed Jupiter 3 to provide users with over 500 Gbps of capacity, with individual speeds of up to 100 Mbps. To offer these metrics (from space, no less), the craft itself has several design features that make it unique among other space-based connective satellites.

Perhaps the most impressive engineering feat of the craft is the 14-total solar array panels that provide the Jupiter 3 with sufficient power. During launch, the panels folded into the bus to reduce the overall size of the payload. After entering orbit, however, the panels brought the craft to its overall length of 127 feet.


The Jupiter 3 satellite, shown with its solar array extended

The Jupiter 3 satellite, shown with its solar array extended, uses the array and a reflector-based antenna to power and transmit data to the Earth's surface from geosynchronous orbit. Image used courtesy of Hughes

For communication with terrestrial stations, the Jupiter 3 satellite operates in the Ka-, Q-, and V-bands. These bands send data to the surface via 300 unique “spot beams” that cover a wide area without running into capacity issues. A reflector-based antenna creates these beams to improve directionality—another important metric for space-based communication.


New Constellations in the Sky

After fully entering geosynchronous orbit 22,000 miles above the surface of the Earth and completing startup tests, the Jupiter 3 satellite will officially enter the Hughes constellation and begin serving customers in North and South America. 

The satellite will use Ka- and V-bands to transmit to consumer and gateway devices and the Q-band to receive information from connected gateways. Onboard thrusters perform the fine-positioning necessary after its initial launch via a SpaceX Falcon Heavy rocket.


Terrestrial gateways can be used with the Jupiter satellite

Terrestrial gateways can be used with the Jupiter satellite constellation to transmit information to the satellites. Image used courtesy of Hughes

It may seem counterintuitive for SpaceX, the company behind the StarLink platform of satellite internet, to aid a potential competitor in launching satellites. However, both SpaceX and Hughes occupy their own areas of space, making them useful for unique applications. The StarLink constellation is in LEO, while Jupiter 3 is in geosynchronous orbit. This disparity in orbit altitude (1,200 vs. 22,000 miles) creates a constant wireless link with no handover at the cost of higher latency. As such, the race to high-speed satellite internet may be a collaborative effort between organizations.


Connecting Anywhere

While it is still too early to call the Jupiter 3 mission a success, current results indicate that the launch is so far going according to plan. After finalizing the deployment and connecting the first batch of customers, analysts can better compare the performance of the satellite to other constellations.

Consumers aren’t the only ones who should celebrate the successful launch; the geosynchronous wide-coverage satellite offers designers new connectivity methods for emerging applications, such as distributed sensor networks for farming or climate science.