Astronomers observe rise and fall of the dust shell of nova V339 Delphini
http://phys.org/news/2016-12-astronomers-fall-shell-nova-v339.html
A team of astronomers led by Aneurin Evans of the Keele University, U.K., has observed the classical nova V339 Delphini (V339 Del for short)
and spotted some peculiar changes in its dust shell. These observations could improve our knowledge about dust formation around stellar remnants.
The results of the observational campaign are presented in a paper published Dec. 19 on the arXiv pre-print repository.
Discovered in August 2013, V339 Delphini is a bright nova in the constellation Delphinus. It is the first nova that has been observed to synthesize
lithium, providing the first direct evidence of the supply of lithium to the interstellar medium by an astronomical object. Interestingly, follow-up
observations after the discovery of V339 Delphini showed that one month after its detection, dust formation commenced in this nova.
To better understand the dust formation process in V339 Delphini, Evans and his colleagues have analyzed sets of data provided by the Stratospheric
Observatory For Infrared Astronomy (SOFIA), the Mt. Abu Infrared Observatory in India, the O'Brien Observatory in Marine on St Croix, Minnesota,
NASA's Infrared Telescope Facility (IRTF), Hawaii, and the Multiple Mirror Telescope (MMT), located on Mt. Hopkins, Arizona.
The data collected from over two years of observations allowed the researchers to distinguish an apparent rise and decline of the mass and radius of
dust grains around this stellar remnant. The team noted that the rapid dust formation occurs around 34th day of observations and afterward, the
infrared emission became dominated by the dust. They also found that the dust is graphitic and its condensation temperature was 1 480 K at that moment.