Scientists were studying spacecraft images on Friday to find out whether a small part of Comet Ison survived its close encounter with the sun.

The comet at first seemed to have fallen apart as it approached the sun’s sizzling surface, but new images showed a streak of light moving away from the sun that some said could indicate it wasn’t game over just yet.

“It certainly appears as if there is an object there that is emitting material,” said Alan Fitzsimmons, an astronomer at Queens University in Belfast, Northern Ireland.

The European Space Agency, which had declared Ison’s death on Twitter late on Thursday, was backtracking early on Friday, saying the comet “continues to surprise.”

Comet Ison, essentially a dirty snowball from the fringes of the solar system, was first spotted by a Russian telescope in September last year.

Some sky gazers speculated early on that it might become the comet of the century because of its brightness, although expectations dimmed over time.

The comet was two-thirds of a mile wide as it got within one million miles (1.6 million kilometres) of the sun, which in space terms basically means grazing it.

NASA solar physicist Alex Young said on Thursday that the comet had been expected to show up in images from the Solar Dynamics Observatory spacecraft at around noon eastern time (1700 GMT), but almost four hours later there was “no sign of it whatsoever.”

Images from other spacecraft showed a light streak continuing past the sun, but Dr. Young said that was most likely a trail of dust continuing in the comet’s trajectory.

Two years ago, a smaller comet, Lovejoy, grazed the sun and survived, but fell apart a couple of days later.

Ison’s mysterious dance with the sun left astronomers puzzled and excited at the same time.

“This is what makes science interesting,” said Prof. Fitzsimmons, who specialises in comets and asteroids. “If we knew what was going to happen, it wouldn’t be interesting.”