NASA's twin ESCAPADE probes are on their way to Mars. The two small spacecraft, named Blue and Gold, each fired their engines during a close flyby of Earth on 7 and 9 November, using the planet's gravity as a slingshot to begin a ten-month cruise to the Red Planet. Rocket Lab, which designed and built both spacecraft, confirmed on 10 November that the trans-Mars injection burns had succeeded.

The manoeuvre is a first for a Mars-bound mission. Rather than heading straight for Mars after launch, the pair spent almost a year waiting in a holding orbit near the Sun-Earth Lagrange point 2, around 1.5 million kilometres from Earth, until the planets moved back into alignment. They then fell back towards Earth and, at the moment they were moving fastest, lit their engines for a powered flyby that added more than 1,000 miles per hour to their speed.

Two burns, two days apart

Blue went first on 7 November, followed by Gold on 9 November. Each spacecraft swung past Earth and fired a single, continuous burn lasting about ten minutes. The burns were carried out autonomously, with operators from Rocket Lab and the University of California, Berkeley watching over both. Rocket Lab said the burns were executed with much greater than 99 percent overall accuracy and a final attitude error of less than one degree.

The trans-Mars injection is one of the two largest propulsive manoeuvres of the mission, alongside the Mars orbit insertion burn scheduled for September 2027. It could not be split into smaller segments, so each spacecraft had to sustain a precisely controlled engine firing at exactly the right moment. A failure would have left the probes stranded, with the next realistic chance to reach Mars about two years away.

Rocket Lab announced the milestone on 10 November, quoting founder and chief executive Sir Peter Beck: "A phenomenal amount of work goes into a successful trans-Mars injection burn, from considered spacecraft design and precision trajectory planning to meticulous on-orbit operations. Performing these TMI maneuvers flawlessly is a testament to the relentless execution of the Rocket Lab team and the ongoing close collaboration of our mission partners at UC Berkeley and NASA. Next stop, Mars."

What Blue and Gold will study at Mars

ESCAPADE stands for Escape and Plasma Acceleration and Dynamics Explorers. Once at Mars, the two spacecraft will work in tandem to measure how the solar wind strips ions from the planet's upper atmosphere. The data will help scientists reconstruct how Mars lost much of its atmosphere over billions of years, characterise the space weather around the planet and inform planning for future human exploration.

The twin-spacecraft design is central to the science. Flying in formation, Blue and Gold can take measurements from two points at once, showing how conditions in Mars' magnetosphere change over time and distance in a way a single orbiter cannot. Mars has no global magnetic field like Earth's. Instead it has a patchy, hybrid magnetosphere shaped by magnetised rocks in its crust, and the mission aims to show how that unusual shield interacts with the solar wind.

A year in waiting

ESCAPADE launched on 13 November 2025 from Cape Canaveral Space Force Station aboard Blue Origin's New Glenn rocket. Earth and Mars were on opposite sides of the Sun at the time, so a direct transfer was impossible. The probes instead entered a looping orbit around the Sun-Earth Lagrange point 2, where they spent nearly a year being commissioned and carrying out trajectory correction burns.

That waiting period was put to use. Operators ran the science instruments as the spacecraft passed through Earth's magnetotail, giving the team an early chance to test the payloads before the long cruise. Rocket Lab said it delivered both spacecraft three and a half years after the contract was awarded, building most of the hardware and software in house, from solar arrays and propellant tanks to star trackers, radios and flight software.

Further course-correction burns during the cruise will refine each spacecraft's path. Blue and Gold are due to arrive at Mars on 7 and 9 September 2027, when they will fire their engines again to enter orbit, and begin their first science formation in 2028.

The mission is the first planetary mission led by the University of California, Berkeley, whose Space Sciences Laboratory leads the science team. Its two probes take their names from the university's colours. NASA had set out the flyby plan in advance, with Blue's closest approach in the early hours of 7 November and Gold's two days later.