Space exploration has always been a challenging and difficult endeavor, and no mission has exemplified this more than Atomos Space’s debut demonstration mission. Despite facing numerous setbacks and close calls, the company has persevered and managed to overcome obstacles that seemed insurmountable.
The mission, named Mission-1, launched into orbit aboard a SpaceX Falcon 9 rocket on March 4. The goals of this mission are ambitious and unprecedented, including complex maneuvers such as rendezvous, docking, orbital transfer, and on-orbit refueling. These objectives require both spacecraft, Quark-LTE and Gluon, to work together seamlessly.
Atomos has encountered two main challenges during the mission: communication and spacecraft rotation. Despite facing significant constraints, limited data, and bandwidth issues, the team has successfully resolved both problems. In fact, due to the limited bandwidth, the flight software updates were limited to a mere 145-character string.
“It’s been an incredibly tough journey,” Atomos CEO and co-founder Vanessa Clark shared with TechCrunch.
COO and co-founder William Kowalski agreed, stating, “What makes it so difficult is that we’re trying to determine the state of a highly complicated system with only 100 bytes of data. It’s like making educated guesses, knowing that one wrong move could lead to disaster.”
It’s a lot of, you’re making guesses as to what is driving this, knowing that some of those guesses could take you down a path where you never recover.
The problems began just hours after the two spacecraft, which were attached, were released from the Falcon 9 upper stage. Although the deployment went as planned, the first signal from the spacecraft was received after seven minutes, followed by a 40-minute gap, then two hours, and finally eight hours. This was not ideal as Atomos was expecting data packets every few minutes.
“The worst day was the Monday when we launched, that evening,” Kowalski recalled. “It was 11 o’clock at night, it was me and the chief engineer…and we haven’t heard anything. We were wondering if we had failed or if the spacecraft had malfunctioned. That was a very tough moment for us.”
It took the mission control team 24 to 48 hours to pinpoint the root cause, with the help of another company with assets in orbit. After making some arrangements, they were able to speak with the chief systems engineer of satellite communications company Iridium. The spacecraft were using modems provided by Iridium and were relying on the company’s satellite constellation for relaying data back to Earth. However, the spacecraft were moving too fast and were in direct opposition, making it impossible for the data to be transmitted to the ground.
To resolve this issue, the engineers implemented a series of software updates that removed the duty cycling of the radios and modified the recovery modes of the spacecraft so that the radio would always remain on, even in a low-power state.
As they were working to solve the communication problem, the team faced yet another challenge: the spacecraft were tumbling at an alarming rate of 55 degrees per second, significantly higher than their designed tolerance of 5 degrees per second. Additionally, the spacecraft were rotating in such a way that their solar arrays were no longer facing the sun, draining the battery rapidly. This led to a race against time as the team had to stabilize the spacecraft before the batteries ran out completely.
“We had two graphs,” Kowalski explained. “One showing the power trend and when we could expect the spacecraft to be facing the sun and have a normal power supply, and the other showing the detumble rate. Our goal was to reduce the detumble rate to zero before the power ran out.”
The limited communication capabilities added to the difficulty as the team could only send new commands during brief periods of communication blackout.
But, after several days of tireless effort, the team managed to stabilize the spacecraft. In a major breakthrough, they were also able to establish high-bandwidth communication through a space-to-space link on Quark-LITE, using the Inmarsat network. During this first attempt, the mission controllers received 17 times more data than they had since the launch, providing valuable insights into the health of the spacecraft. While there were some negative findings, such as a damaged battery pack and a GPS issue, these were considered solvable problems by the team.
By Tuesday or Wednesday, the company aims to start commissioning the propulsion system. If all goes according to plan, and the engineers can confirm the accuracy and control of the propulsion system, they will then turn off the torque rods and reaction wheels. The final goal is to separate the spacecraft after a month, expected to be completed by the end of June.
Kowalski and Clark attributed the success of their startup to their vertical integration approach. With a team that worked an intense 100-hour week immediately after deployment, Atomos was able to leverage its in-depth knowledge of the spacecraft design to overcome the challenges that arose.
“Although it has been a painful experience, as the CEO of Nvidia says, ‘I wish upon you great suffering.’ We have gone through the tough times and it wasn’t pleasant at the moment, but now we feel more accomplished,” Clark said.
