New imaging of V605 Aql , was obtained in 2009 with HST /WFPC2 , which had a nova-like outburst in 1919 , and is located at the center of the planetary nebula ( PN ) , Abell 58 .
This event has long been ascribed to a final helium shell flash , but it has been suggested recently that it may instead have been an ONe nova .
The new images provide an 18 year baseline for the expansion of the ejecta from the 1919 event .
In addition , the central star has been directly detected in the visible for the first time since 1923 , when it faded from sight due to obscuration by dust .
The expansion of the ejecta has a velocity of \sim 200 km s ^ { -1 } , and an angular expansion rate of \sim 10 mas yr ^ { -1 } , consistent with a 1919 ejection .
This implies a geometric distance of 4.6 kpc for V605 Aql , consistent with previous estimates .
The gas mass in the central knot of ejecta was previously estimated to be 5 \times 10 ^ { -5 } M _ { \hbox { $ \odot$ } } .
It is estimated that warm dust associated with this gas has a mass of \sim 10 ^ { -5 } M _ { \hbox { $ \odot$ } } .
There is also evidence for a significant amount , 10 ^ { -3 } M _ { \hbox { $ \odot$ } } , of cold ( 75 K ) dust , which may be associated with its PN .
The knot ejected in 1919 is asymmetrical and is approximately aligned with the asymmetry of the surrounding PN .
Polarimetric imaging was obtained to investigate whether the 2001 spectrum of V605 Aql was obtained primarily in scattered light from dust in the central knot , but the signal-to-noise in the data was insufficient to measure the level of polarization .