By Raymond Rolak
A newly discovered comet has excited the astronomical community this week because it appears to have originated from outside the solar system.
For decades, astronomers have speculated that the space between stars may be populated by solar minor bodies — comets and asteroids. These are thought to have been ejected from their home planetary systems.
Studies have also suggested that these bodies may occasionally pass through our Milky Way Solar System and be identified thanks to their strongly open orbits. The discovery of ‘Oumuamua two years ago brought the long-awaited confirmation, sparking hopes for subsequent detections.
A team of scientists led by astronomers from the Jagiellonian University in Krakow, Poland had done their homework well ahead of time. Prompted by the earlier visit of ‘Oumuamua, they created a computer program nicknamed “Interstellar Crusher” that scanned tirelessly through online data of newly-found comets and asteroids in search of guests from far away.
It’s only the second interstellar comet ever detected in our solar system and the first that looks like a traditional comet. The first one, cigar-shaped ‘Oumuamua, which was discovered in 2017, did not resemble a comet in the usual sense.
The unusual body was spotted in August by a Crimean (Ukraine) amateur astronomer, Gennady Borisov. It was swiftly identified as an outcast from another star system and may have been wandering the Milky Way for millions if not billions of years.
“This is the first comet known to science that arrived from outside the solar system, and it is completely similar to those we see inside the solar system,” said Michal Drahus, an astronomer at Jagiellonian University in Krakow, Poland.
On September 8, 2019 at 04:15 universal time, the program issued a red alert and notified the team of a possible new hyperbolic object arriving from interstellar space. “This code was written specifically for this purpose, and we really hoped to receive this message one day. We only didn’t know when,” said Piotr Guzik of the Jagiellonian University, who led the study. A closer investigation into the object’s orbit confirmed its exosolar origin.
Two days after receiving the alert, the team was already scrutinizing their first images of the object obtained at the William Herschel Telescope on La Palma, Spain, and getting ready to receive more data from the larger Gemini North Telescope on Mauna Kea, Hawaii. With its high elevation, dry environment, and stable airflow, Mauna Kea’s summit is one of the best sites in the world for astronomical observation. Since the creation of an access road in 1964, thirteen telescopes funded by eleven countries have been constructed at the summit. The Mauna Kea Observatories are used for scientific research across the electromagnetic spectrum.
