World / Science & Health

Hubble Telescope zooms in on interstellar visitor

AP, Reuters

The Hubble Space Telescope has captured the best pictures yet of our newest interstellar visitor.

The comet is zooming by us at a blistering 110,000 mph (177,000 kph). Hubble caught some glam shots over the weekend from a distance of 260 million miles (420 million km). The photos were released Wednesday.

It is the second known interstellar visitor to swoop through our solar system. An amateur astronomer from Crimea, Gennady Borisov, discovered the comet in August, two years after the first alien guest, a cigar-shaped rock known as ‘Oumuamua, popped up.

“It’s a puzzle why these two are so different,” David Jewitt of the University of California, Los Angeles, who led the Hubble observation team, said in a statement.

On the other hand, it is “very remarkable” that the comet’s properties appear to be similar to those of our own solar system’s building blocks, said Amaya Moro-Martin of the Space Telescope Science Institute in Baltimore.

Polish astronomers using ground telescopes have reported that the comet — called Comet 2I/Borisov — looks reddish, with a nucleus about 1 mile (2 km) across.

“Its properties determined so far — morphology, color, estimated size — are remarkably similar to the native solar system comets. This is important because it shows that comets exist in interstellar space, confirming long-standing predictions, and it tells us that comets similar to the ones we know from this solar system also form around other stars,” said astronomer Michal Drahus of Jagiellonian University in Poland.

Both 2I/Borisov and ‘Oumuamua formed in other planetary systems and were ejected by gravitational perturbations into interstellar space as orphans wandering the cosmos.

The speed and path of 2I/Borisov demonstrated that it did not originate in our solar system, Jagiellonian University astronomer Piotr Guzik said. Guzik added that he expects that within a decade or so a space probe will be sent from Earth to visit an interstellar object.

The comet will make its closest approach to the sun in December and reach Jupiter’s distance by mid-2020, before heading back toward interstellar space. Hubble — along with other telescopes — will be on the lookout into next year.