WASHINGTON-Astronomers are gathering measurements on a presumed interstellar comet, providing clues about its chemical composition.

The object, C/2019 Q4 (Borisov), is only the second interstellar object ever identified, after ‘Oumuamua, which was spotted in 2017. Telescopes across the world are being trained on the object.

Early results suggest its make-up might not differ that much from comets in our cosmic neighbourhood.

One expert told the BBC that the object was about to become one of the most famous comets in history.

The team used the Osiris instrument at the 10.4m Gran Telescopio Canarias in La Palma, Spain, to obtain visible spectra - measurements of sunlight reflected by Borisov.

By studying these spectra, scientists can draw conclusions about its chemical composition, including how it might differ from comets that were “born” around the Sun.

“The spectrum is the red side of the comet’s total spectrum, so the only thing we can see in the spectrum is the slope,” said Miquel Serra Ricart, from the Instituto de Astrofísica de Canarias (IAC) in Tenerife.

“This inclination is similar to Solar System comets.”

Astronomer Julia de León, also from the IAC, said this indicated that Borisov’s “composition must be similar” to comets in our neighbourhood.

Measurements of the comet have been taken with the Gran Telescopio Canarias in Spain

In coming days, the team will obtain measurements of the “blue” part of the comet’s spectrum. These are expected to be more informative as regards its composition. They could reveal whether it contains organic (carbon-based) molecules, such as cyanide (CN) - seen in Solar System comets.

So while the data so far suggests that Borisov resembles objects found close to home, the scientists could yet see interesting deviations when they analyse upcoming data.

Some researchers think that comets could have seeded the early Earth with these organic molecules, potentially playing a role in the origins of life. If they’re found on a comet from another star system, it could have profound implications for the potential for life on exoplanets.

“For us it would be better if the spectrum is different,” Dr Ricart told BBC News. But he said a composition similar to Solar System comets “would also be an important conclusion”.

He said: “It would mean that in other sites of our galaxy, the processes and conditions are similar to those in our Solar System.”