SpaceX Dragon fires thrusters to boost ISS orbit for the 1st time

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Data from today's reboost to help inform the design for SpaceX's ISS deorbit vehicle.

A SpaceX Dragon spacecraft fires its thrusters under green and red lights with a nighttime Earth in the background while docking.
(Image credit: NASA/Don Pettit)

The International Space Station is going a just tiny bit faster today, after receiving an orbital boost from SpaceX's Dragon spacecraft.

SpaceX's 31st commercial resupply mission lifted off Nov. 4, launching a Dragon cargo vehicle to rendezvous with the International Space Station (ISS), docking to the station's forward-facing port the next day. Today (Nov. 8), for the first time, Dragon performed an orbit-raising maneuver to stabilize the ISS's trajectory in low-Earth orbit.

Such maneuvers are routine for the orbital lab, which requires periodic boosts to maintain its altitude above Earth and prevent its orbital decay into the planet's atmosphere. Historically, this has been accomplished using Russia's Soyuz and Progress vehicles, and other spacecraft, but, for the first time, it has now been performed SpaceX's Dragon. The milestone marks a symbolic beginning of the end for the ISS, as data from the maneuver will be used toward the design of the deorbit vehicle NASA has contracted SpaceX to construct to plunge the decommissioned space station into the Pacific Ocean sometime after 2030.

Today's reboost began with the ignition of Dragon's thrusters around 12:50 p.m. ET (1750 GMT). The burn was expected to last about 12.5 minutes to raise the station's orbit

"NASA and SpaceX monitored operations as the company’s Dragon spacecraft performed its first demonstration of reboost capabilities for the International Space Station at 12:50pm ET today," NASA posted on X.

Related: SpaceX Dragon cargo capsule arrives at ISS on 31st resupply mission (video)

Dragon isn't the first U.S.-built spacecraft to lend its fuel to the space station's orbit. NASA tested an ISS orbit reboost using a Northrop Grumman Cygnus cargo vehicle in 2022. The data from Dragon's reboost, however, will ultimately pave the way for a catastrophic "un-boosting" of the space station's orbit.

The ISS has been in continuous use and occupancy for almost 25 years now. NASA has projected the ISS's viability through the end of this decade. Citing aging technology, increasing maintenance requirements and rising costs, the space agency aims to retire the space station no earlier than 2030, and in July, awarded SpaceX the contract to develop the vehicle tasked with safely plummeting the football field-size spacecraft into the sea.

When the burden of ongoing ISS costs are alleviated from its budget, NASA will count on the availability of new commercially operated space stations to continue its research in low-Earth orbit. The space station's retirement will free up financial room for the space agency to expand endeavors like the Artemis Program and other deep space exploration missions.

Jared Metter, director of flight reliability at SpaceX, expressed optimism during a press conference Monday (Nov. 4), saying today's attitude control maneuver was "a good demonstration" of Dragon's capabilities as the company designs the ISS deorbit vehicle.

RELATED STORIES:

— SpaceX Crew-9 astronauts, including Boeing Starliner crew, fly Dragon spacecraft to new ISS parking spot (video)

— SpaceX launches 3 tons of cargo on 31st ISS resupply flight for NASA (video)

— SpaceX has dreamed up a Dragon ship on steroids to drag the ISS out of space

Though international tensions were inflamed following Russia's invasion of Ukraine in 2022, the U.S.-Russian partnership as it pertains to the ISS has persisted. Dragon's success, however, does eliminate another U.S. reliance on Russia for operation of the space station, should that partnership dissolve.

Between the retirement of the space shuttle in 2011 and the beginning of Dragon's crewed missions, the only way for NASA astronauts to launch to the ISS was aboard Russian spacecraft. SpaceX's Crew Dragon returned the launch of NASA astronauts to American soil in 2020, and has now proven it can maintain the space station's orbit, indefinitely.

While NASA has committed to its ISS partnership through 2030, Russia, as of yet, is only committed through 2028, stating its intent to launch a new Russian space station into polar orbit by 2027.

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Josh Dinner
Josh Dinner
Writer, Content Manager

Josh Dinner is Space.com's Content Manager. He is a writer and photographer with a passion for science and space exploration, and has been working the space beat since 2016. Josh has covered the evolution of NASA's commercial spaceflight partnerships, from early Dragon and Cygnus cargo missions to the ongoing development and launches of crewed missions from the Space Coast, as well as NASA science missions and more. He also enjoys building 1:144 scale models of rockets and human-flown spacecraft. Find some of Josh's launch photography on Instagram and his website, and follow him on Twitter, where he mostly posts in haiku.

9 Comments Comment from the forums
  • M.S.
    "The International Space Station is going a just tiny bit faster today, after receiving an orbital boost from SpaceX's Dragon spacecraft."

    I believe the ISS will l be actually going a just tiny bit slower today, as the purpose of the orbital boost was to rise the ISS into a bit higher orbit, and higher orbit means lower orbital speed.
    Reply
  • Unclear Engineer
    Not quite so easy to explain, but the speed is faster, where the boost occurred.

    I did not look up the actual parameters of the boost. But, generally, the boost should occur at the high point (apogee) of the orbit, and increase speed in the direction of the orbit. That will bring up the altitude of the low point of the orbit (perigee). Because the speed is highest at the low point, M.S. is correct that the average speed of an orbit around the Earth would be slower after the boost. But, it will be going faster than it was previously going at the high point. It will be going slower at the lowest point of the new orbit, compared to the unboosted orbit.
    Reply
  • Aramis
    Cygnus has already reboost the ISS

    https://www.space.com/space-station-cygnus-orbit-reboost-success
    Northrop Grumman's Cygnus cargo ship boosts International Space Station's orbit
    Reply
  • Unclear Engineer
    Yes, so has the Russian Progress supply ship.

    This is another one of those headlines that seems to imply something more special than it actually is. This isn't the first time that the ISS orbit has been boosted - that is fairly routine. It is the first time that a SpaceX rocket has been used to do it. And, that is why it is being done with the Dragon capsule, so that SpaceX can get the data it wants to design a purpose-built rocket to deorbit the ISS.
    Reply
  • Classical Motion
    It wouldn’t surprise me that if today, all they do is punch in the new altitude needed. And then let sensors, software and thrusters complete the task. Getting a feedback feel, for future tasks. Live feedback control, not pre-programmed control.

    An experience catalog. Experience programming.
    Reply
  • Unclear Engineer
    They might automate the boost thrust sequence. But, given the issues with stuck valves, thruster malfunctions, etc, on multiple ships, recently, I expect that there is going to be a human watching the machines with the ability to stop the rocket motors if things don't seen to stay within specs.
    Reply
  • Classical Motion
    I did a little process programming about 25 yrs. ago. Any error or out of parameter condition is handled by software. It’s much quicker and the correct procedure can be assured. Hopefully preventing or limiting damage.

    But any new hardware or software change needs to be watched like a first child bike ride. And with space vehicles I would want someone watching a monitor all the time. Bridge duty.

    But I have no idea of what goes on up there.

    And I never had a chance to work with learning software. I probably assume too much.
    Reply
  • M.S.
    Unclear Engineer said:
    Not quite so easy to explain, but the speed is faster, where the boost occurred.

    I did not look up the actual parameters of the boost. But, generally, the boost should occur at the high point (apogee) of the orbit, and increase speed in the direction of the orbit. That will bring up the altitude of the low point of the orbit (perigee). Because the speed is highest at the low point, M.S. is correct that the average speed of an orbit around the Earth would be slower after the boost. But, it will be going faster than it was previously going at the high point. It will be going slower at the lowest point of the new orbit, compared to the unboosted orbit.
    I don't know the parameters of the new orbit either, but the boost increased the total (kinetic+potential) energy of the the ISS.
    Since the total energy is determined by the semi-major axis of the orbit, higher total energy means larger semi-major axis, which in turn means lower average speed. The question is whether the boost changed the eccentricity of the orbit. If the eccentricity did not change, then both perigee and apogee have larger values, and therefore both perigee and apogee speeds are lower than before the boost. But if the eccentricity increased, it might well be that perigee speed is now larger than before, and apogee speed much lower that before.
    Reply
  • Unclear Engineer
    The goal is to get the ISS out of the drag-inducing upper atmosphere at the lowest point of its orbit, so the most "bang for the buck" it to raise the perigee. And that means increasing the speed at the apogee.

    But, you are correct that will create a lower average speed over the entire orbit.

    Still, you are picking nits between increasing speed at the apogee vs decreasing average orbital speed when you do that.

    Most people do not understand orbital mechanics. So, the article just said the thrust increased the speed to boost the orbit. People might have otherwise thought that the thrust would just point "up" (radially away from the Earth) to boost the orbit. But, that would have increased the eccentricity, and, depending on where applied, could be counter-productive for reducing drag effect per orbit.
    Reply