Nuclear ashes and outflow in the eruptive star Nova Vul 1670

Abstract

CK Vulpeculae was observed in outburst in 1670-16721, but no counterpart was seen until 1982, when a bipolar nebula was found at its location. Historically, CK Vul has been considered to be a nova (Nova Vul 1670), but a similarity to 'red transients', which are more luminous than classical nova and thought to be the result of stellar collisions, has re-opened the question of CK Vul's status. Red transients cool to resemble late M-type stars, surrounded by circumstellar material rich in molecules and dust. No stellar source has been seen in CK Vul, though a radio continuum source was identified at the expansion centre of the nebula. Here we report CK Vul is surrounded by chemically rich molecular gas with peculiar isotopic ratios, as well as dust. The chemical composition cannot be reconciled with a nova or indeed any other known explosion. In addition, the mass of the surrounding gas is too high for a nova, though the conversion from observations of CO to a total mass is uncertain. We conclude that CK Vul is best explained as the remnant of a merger of two stars.

an older version of an article that appeared in Nature; published in Nature, online version, 23 March 2015

References in corpus (5)

• A Spitzer/IRS Spectrum of the 2008 Luminous Transient in NGC 300: Connection to Proto-Planetary Nebulae
• Keck/HIRES spectroscopy of V838 Monocerotis in October 2005
• The enigma of the oldest `nova': the central star and nebula of CK Vul
• AKARI-CAS --- Online Service for AKARI All-Sky Catalogues
• Extended CO emission in the field of the light echo of V838 Mon

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