WASHINGTON — NASA has hailed an agreement with the Space Force to share information on near Earth object impacts as a key step forward in planetary defense, even as the agency defers work on a mission it says is critical to tracking such objects.
NASA announced April 7 that it signed an agreement with the U.S. Space Force to release data from military satellites of bolides, meteors that enter and explode in the upper atmosphere. The data is in the form of lightcurves, or changes in brightness of these objects over time, which NASA says can help scientists better model the effects of near Earth object (NEO) impacts.
“The release of these new bolide data demonstrates another key area of collaboration between NASA and the U.S. Space Force and helps further the pursuit of improved capabilities for understanding these objects and our preparedness to respond to the impact hazard NEOs pose to Earth,” Lindley Johnson, NASA’s planetary defense officer, said in an agency statement.
The data released by the Space Force includes one bolide detected in January 2014 with an unusually high velocity that led some astronomers to speculate it came from outside the solar system. However, NASA noted in its statement that the limited data “makes it difficult to definitively determine if the object’s origin was indeed interstellar.”
The announcement came a day after a planetary defense panel at the 37th Space Symposium that included representatives of NASA and the Space Force. “We are working today to disseminate that data more quickly and more widely than ever before,” Space Force Lt. Gen. John Shaw, deputy commander of U.S. Space Command, said of sharing bolide data.
He emphasized the cooperative role the Space Force plans with NASA and other agencies on planetary defense through a 2018 strategy and action plan. That included participating in a tabletop exercise recently that simulated a NEO that threatened to hit North Carolina.
One lesson that came out of that was the need to better think about how government agencies would work together to deal with an impact threat, or an impact itself. “That’s probably something that the president and the National Security Council would probably bring to bear, but it’s worth thinking it through a little more than we have, to at least have some understanding of that problem statement and potential solutions,” he said.
A real-world demonstration of dealing with NEO threats took place March 11, when astronomers discovered a very small asteroid, less than two meters across, hours before it hit the Earth. The object exploded harmlessly in the upper atmosphere northeast of Iceland with the energy equivalent of about four kilotons of TNT.
“It allowed us to exercise our whole network of detection, warning and international collaboration that we have in place,” said Lori Glaze, director of NASA’s planetary science division.
The impact illustrated the need to improve detection capabilities to detect more objects and with more advance notice of any impacts. “By using ground-based assets, we’ve pretty much maxed out on the number of objects we can detect each year,” she said.
NASA’s NEO Surveyor mission, in its early stages of development, is designed to do just that. “NEO Surveyor is specifically designed to detect and characterize” such objects, she said, allowing NASA to speed up meeting a long-standing congressional directive to discover at 90% of NEOs 140 meters or more across. “We expect that, once it’s launched into space, we could, in fact, complete that goal of 90% detection of those objects 140 meters and larger within a 10-year period. So, we’re excited about that mission moving forward.”
However, NEO Surveyor is facing delays in NASA’s proposed budget. The fiscal year 2023 budget proposal seeks to delay development of NEO Surveyor by at least two years, to 2028, to address cost growth in flagship science programs like Mars Sample Return and Europa Clipper.
Glaze, in her remarks at the conference panel, hinted at the issue but emphasized the importance of NEO Surveyor to planetary defense. “From my perspective, that is the biggest gap that we have right now,” she said. “We’ve got to identify more of these objects that are hazardous to Earth.”
“If you’re following along with NASA’s budget, it’s one that’s had a bit of a rocky start,” she added, referring to NEO Surveyor. “We’re still trying to get that to move forward.”