NASA decides not to launch two already-built asteroid probes

Two small spacecraft should have now been cruising through the Solar System on the way to study unexplored asteroids, but after several years of development and nearly $50 million in expenditures, NASA announced Tuesday the probes will remain locked inside a Lockheed Martin factory in colourado.

That’s because the mission, called Janus, was supposed to launch last year as a piggyback payload on the same rocket with NASA’s much larger Psyche spacecraft, which will fly to a 140-mile-wide (225-kilometer) metal-rich asteroid—also named Psyche—for more than two years of close-up observations. Problems with software testing on the Psyche spacecraft prompted NASA managers to delay the launch by more than a year.

An independent review board set up to analyze the reasons for the Psyche launch delay identified issues with the spacecraft’s software and weaknesses in the plan to test the software before Psyche’s launch. Digging deeper, the review panel determined that NASA’s Jet Propulsion Laboratory, which manages the Psyche mission, was encumbered by staffing and workforce problems exacerbated by the COVID-19 pandemic.

Psyche is now back on track for liftoff in October on a SpaceX Falcon Heavy rocket, but Janus won’t be aboard.

Janus was designed to fly to two binary asteroids—consisting of two bodies near one another—that orbit the Sun closer to Earth than the metallic asteroid Psyche. While the Psyche mission can still reach its asteroid destination and accomplish its science mission with a launch this year, the asteroids targeted by Janus will have changed positions in the Solar System by too much since last year. They are no longer accessible to the two Janus spacecraft without flying too far from the Sun for their solar arrays to generate sufficient power.

When it became clear the two Janus target asteroids were no longer reachable, scientists on the Janus team and NASA management agreed last year to remove the twin spacecraft from the Psyche launch. Scientists considered other uses for the suitcase-size Janus spacecraft, which were already built and were weeks away from shipment to Florida to begin final launch preparations when NASA decided to delay the launch of Psyche.

One of the ideas to repurpose the Janus spacecraft was to send the probes to fly by asteroid Apophis, a space rock bigger than the Empire State Building that will encroach within 20,000 miles (32,000 kilometers) from our planet’s surface in 2029. For a time soon after its discovery in 2004, scientists said there was a small chance Apophis could impact Earth in 2029 or later this century, but astronomers have now ruled out any risk of a collision for the next 100-plus years.

It came down to money

In the end, Janus fell victim to the delay of the Psyche mission and tight budget constraints at NASA. The agency said Tuesday it has directed the Janus team to “prepare the spacecraft for long-term storage.”

“NASA considered various potential opportunities and requirements for alternative missions using the twin spacecraft, with a focus primarily on asteroid science,” said Eric Ianson, deputy director of NASA’s planetary science division, in a written response to questions from Ars. “However, limited resources the next few years drove the decision to not pursue one of these alternatives at this time.”

NASA’s planetary science budget is strained by rising costs on several missions already on the books, including the multibillion-dollar Mars Sample Return project, which is still in an early stage of development. The sample return mission aims to retrieve Martian rock specimens and bring them back to Earth for analysis. The Europa Clipper mission, now undergoing final assembly for launch next year, has also seen cost increases, according to Tom Statler, an official in NASA’s planetary science division.

The debt ceiling budget deal struck last month by President Biden and congressional Republicans set federal spending limits that will likely impact NASA’s overall funding levels.

“We’re looking at a challenging time ahead, and everybody needs to be aware of that,” Statler said Tuesday in a meeting of the Small Bodies Advisory Group, which represents the asteroid science community. “The budget is definitely not conducive to considering new starts (of planetary science missions) right now.”

NASA has not ruled out using the twin asteroid probes for a future mission if funding becomes available, but Ianson said: “There are no current plans for use of these spacecraft.”

According to Ianson, NASA has spent nearly $50 million on the Janus mission since the agency formally approved it for development in 2020. That funding represents the majority of the project’s original cost cap of $55 million.

It’s unusual, but not unprecedented, for NASA to cancel a science mission after spending significant money, but the terminations are usually triggered by cost overruns or insurmountable technical problems with the spacecraft. In the case of Janus, engineers were assessing an issue uncovered during ground testing of the spacecraft’s electric thrusters. Concerns with the propulsion system limited the alternative missions available for NASA to review after the launch delay from last year, but the Janus science team was confident the issue was not a problem for a potential backup mission to Apophis.

NASA selected the Janus mission proposal from a science team led by principal investigator Dan Scheeres of the University of Colorado. Janus was part of NASA’s SIMPLEx program, which stands for Small, Innovative Missions for Planetary Exploration. SIMPLEx was set up to provide NASA funding for relatively low-cost robotic missions to explore the Solar System, taking advantage of a trend in smaller spacecraft, miniaturized instruments, and rideshare launch opportunities.

Two other SIMPLEx missions selected by NASA at the same time as Janus are proceeding toward launch. One of the missions, called Lunar Trailblazer, will hitch a ride to the Moon with a commercial lander from Intuitive Machines. The other project is called EscaPADE, which will fly to Mars to study the red planet’s atmosphere and magnetosphere.

It’s assumed by NASA that the small planetary science missions are more high-risk than more expensive Solar System probes, like the Psyche mission, which has a budget of more than $1.1 billion after the one-year launch delay.

Under its new flight plan, the Psyche spacecraft will fly by Mars for a gravity assist maneuver to slingshot into the asteroid belt, where it will rendezvous and enter orbit around the asteroid Psyche in August 2029. Scientists theorize that asteroid Psyche could be the remnant of a nickel-iron core of a failed planet that was destroyed in the chaotic ancient Solar System.