Military researchers at the US Space Command recently discovered the first known interstellar meteor, a rock mass from space that originates outside of our solar system, to ever have hit Earth. In 2014, an oblong object entered Earth’s atmosphere and landed in the Pacific Ocean. NASA and other intelligence agencies mistakenly buried evidence of the cosmic rubble in the fireball database for years, until a Harvard student came poking around in 2019.
At a glance
- The US military recently agreed with researchers that a 2014 meteorite originated from outside of Earth’s solar system
- Researchers argued in 2019 that based on velocity, the original meteorite could not have come from close orbit
- The findings mean that evidence of interplanetary life could theoretically exist on the rubble
- Most of the meteor burned off in our atmosphere, with the rest falling somewhere in the Pacific Ocean
Student Amir Siraj and veteran astronomer Avi Loeb hypothesized three years ago that the 2014 rubble entry was actually interstellar. “Its high … speed implies a possible origin from the deep interior of a planetary system or a star in the thick disk of the Milky Way galaxy,” they wrote at the time. The U.S. military recently finished calculating probabilities and then declassifying the results. Turns out, the study’s authors were correct — the rubble did originate outside of our solar system.
The USSC Twitter account shared a memo from Space Command to NASA’s science head last week summing up the situation.
“Dr. Joel Mozer, the Chief Scientist of Space Operations Command … reviewed analysis of additional data available to the Department of Defense related to this finding,” the memo reads. “Dr. Mozer confirmed that the velocity estimate reported to NASA is sufficiently accurate to indicate an interstellar trajectory.”
Before presenting their findings to the military, Siraj and Loeb had to study the meteor’s velocity based on heliocentric energy
Researchers believe that the 2014 meteor mostly burned up in the atmosphere; and that small bits fell into the Pacific Ocean. The research pair said they would like to find the rubble in the ocean. It could then provide evidence regarding interplanetary life forms.
“The reported meteor entered the solar system with a speed of 60 km/s [134,216 mph],” Loeb said to CNET journalist Eric Mack in 2019. “Such a high ejection speed can only be produced in the innermost cores of planetary systems — interior to the orbit of the Earth around a star like the sun, but in the habitable zone of dwarf stars, hence allowing such objects to carry life from their parent planets.”
To reach the interstellar conclusion, Loeb and Siraj first noted the meteor’s high velocity. Since the meteor hit the Earth from behind, Siraj’s calculations said the meteor was actually traveling at about 37.3 miles per second relative to the sun. He then mapped out the meteor’s trajectory. He found it was in an unbound orbit, different than the closed orbit of other meteors. Therefore, rather than circling around the sun like other meteors, this meteor originated from a different system.
“Presumably, it was produced by another star, got kicked out of that star’s planetary system and just so happened to make its way to our solar system and collide with Earth,” Siraj said.