April 19, 2024

Working Overtime: NASA’s Deep Space Atomic Clock Successfully Completes Mission

This illustration reveals NASAs Deep Space Atomic Clock technology presentation and the General Atomics Orbital Test Bed spacecraft that hosts it. Spacecraft might one day depend on such instruments to browse deep area. Credit: NASA
Tailored toward enhancing spacecraft navigation, the technology presentation operated far longer than planned and broke the stability record for atomic clocks in area.
For more than 2 years, NASAs Deep Space Atomic Clock has been pushing the timekeeping frontiers in space. On September 18, 2021, its mission came to an effective end.
The instrument is hosted on General Atomics Orbital Test Bed spacecraft that was released aboard the Department of Defense Space Test Program 2 mission June 25, 2019. Its goal: to test the feasibility of using an onboard atomic clock to enhance spacecraft navigation in deep space.

The Deep Space Atomic Clock has to do with 10 inches (25 centimeters) on each side, roughly the size of a toaster. Its compact style was a key requirement, and an even smaller model will fly aboard NASAs VERITAS spacecraft. Credit: NASA/JPL-Caltech
Presently, spacecraft count on ground-based atomic clocks. To measure a spacecrafts trajectory as it takes a trip beyond the Moon, navigators utilize these timekeepers to exactly track when those signals are sent out and gotten. Because navigators understand that radio signals travel at the speed of light (about 186,000 miles per second, or 300,000 kilometers per second), they can use these time measurements to determine the spacecrafts specific range, speed, and instructions of travel.
The farther a spacecraft is from Earth, the longer it takes to send out and get signals– from several minutes to a few hours– substantially delaying these calculations. With an onboard atomic clock coupled with a navigation system, the spacecraft might immediately calculate where it is and where it is going.
The Deep Space Atomic Clock was introduced on a SpaceX Falcon Heavy rocket as part of the Department of Defenses Space Test Program-2 (STP-2) objective from Launch Complex 39A at NASAs Kennedy Space Center in Florida on Tuesday, June 25, 2019. Credit: NASA/Joel Kowsky
Constructed by NASAs Jet Propulsion Laboratory in Southern California, the Deep Space Atomic Clock is an ultra-precise, mercury-ion atomic clock enclosed in a little box that determines about 10 inches (25 centimeters) on each side– roughly the size of a toaster. Designed to endure the rigors of launch and the cold, high-radiation environment of area without its timekeeping efficiency degrading, the Deep Space Atomic Clock was a technology presentation intended to carry out technological firsts and fill important understanding spaces.
View this video explainer to learn why precise timekeeping in area is vital and how NASAs Deep Space Atomic Clock will make future spacecraft less reliant on Earth to browse autonomously. Credit: NASA/JPL-Caltech
After the instrument completed its 1 year primary objective in Earth orbit, NASA extended the mission to gather more data because of its extraordinary timekeeping stability. But prior to the tech demo was powered off on Sept. 18, the mission worked overtime to extract as much information as possible in its last days.
” The Deep Space Atomic Clock mission was a resounding success, and the gem of the story here is that the technology presentation ran well past its intended functional period,” stated Todd Ely, primary investigator and project supervisor at JPL.
The information from the trailblazing instrument will assist establish Deep Space Atomic Clock-2, a tech demonstration that will travel to Venus aboard NASAs Venus Emissivity, Radio Science, InSAR, Topography & & Spectroscopy (VERITAS) spacecraft when it releases by 2028. This will be the very first test for an atomic clock in deep space and a huge improvement for increased spacecraft autonomy.
Stability Is Everything
While atomic clocks are the most steady timekeepers on the world, they still have instabilities that can cause a tiny lag, or “balanced out,” in the clocks time versus the real time. Left uncorrected, these offsets will accumulate and might result in large errors in placing. Portions of a 2nd might mean the difference in between securely coming to Mars or missing the planet entirely.
Updates can be beamed from Earth to the spacecraft to remedy for these offsets. International Positioning System (GPS) satellites, for instance, bring atomic clocks to assist us receive from point A to B. To make sure they keep the time precisely, updates need to be frequently transmitted to them from the ground. However needing to send regular updates from Earth to an atomic clock in deep area would not be useful and would beat the function of gearing up a spacecraft with one.
This is why an atomic clock on a spacecraft exploring deep area would need to be as stable as possible from the beginning, permitting it to be less based on Earth to be updated.
” The Deep Space Atomic Clock was successful in this objective,” said JPLs Eric Burt, an atomic clock physicist for the mission. “We have achieved a new record for long-lasting atomic clock stability in space– more than an order of magnitude better than GPS atomic clocks. This suggests that we now have the stability to enable for more autonomy in deep space objectives and possibly make GPS satellites less depending on twice-daily updates if they carried our instrument.”
3 distinctive posters featuring the Deep Space Atomic Clock and how future variations of the tech demo may be utilized by spacecraft and astronauts are readily available for download here. Credit: NASA/JPL-Caltech
In a recent research study, the Deep Space Atomic Clock team reported a variance of less than 4 nanoseconds after more than 20 days of operation.
Like its predecessor, the Deep Space Atomic Clock-2 will be a tech demonstration, suggesting that VERITAS will not depend on it to satisfy its goals. But this next iteration will be smaller sized, use less power, and be developed to support a multi-year objective like VERITAS.
” It is an amazing achievement by the group– the innovation demonstration has proven to be a robust system in orbit, and we are now anticipating seeing an improved version go to Venus,” said Trudy Kortes, director of technology demonstrations for NASAs Science and Technology Mission Directorate (STMD) at NASA Headquarters in Washington. “This is what NASA does– we establish new innovations and enhance existing ones to advance robotic and human spaceflight. The Deep Space Atomic Clock really has the prospective to transform how we explore deep space.”
Jason Mitchell, the director of the Advanced Communications & & Navigation Technology Division of NASAs Space Communications and Navigation (SCaN) at the firms headquarters concurred: “The instruments efficiency was truly extraordinary and a testimony to the ability of the group. Moving forward, not just will the Deep Space Atomic Clock allow considerable, brand-new operational abilities for NASAs robotic and human expedition missions, it may likewise allow deeper exploration of the basic physics of relativity, similar to the clocks supporting GPS have done.”
More About the Mission
The Deep Space Atomic Clock is hosted on a spacecraft provided by General Atomics Electromagnetic Systems of Englewood, Colorado. It is sponsored by STMDs Technology Demonstration Missions program situated at NASAs Marshall Space Flight Center in Huntsville, Alabama, and SCaN within NASAs Human Exploration and Operations Mission Directorate. JPL manages the task.

Having to send out regular updates from Earth to an atomic clock in deep area would not be practical and would defeat the purpose of equipping a spacecraft with one.
” The Deep Space Atomic Clock was successful in this objective,” stated JPLs Eric Burt, an atomic clock physicist for the objective. “We have attained a brand-new record for long-lasting atomic clock stability in space– more than an order of magnitude better than GPS atomic clocks. The Deep Space Atomic Clock really has the possible to transform how we explore deep area.”
The Deep Space Atomic Clock is hosted on a spacecraft supplied by General Atomics Electromagnetic Systems of Englewood, Colorado.