We seek the help of talented amateurs and undergraduates to help observe the White Dwarf WD 1145+017; the goal is to help
determine the number and the properties of the multiple
disintegrating planetesimals believed to be orbiting this white dwarf. All amateurs/undergraduates or other individuals
who submit usable light curves will be included as co-authors in the resulting scientific publication. Further details on how to help out are below.
Summary of the Multiple Disintegrating Planetesimals Orbiting WD 1145+017
The White Dwarf WD 1145+017 has been found to have multiple disintegrating planetesimals in short period (< 5 hour) orbits. The likely explanation
for these multiple planetesimals is that a planet or asteroid has been tidally disrupted, and we are observing this system in the midst
of being tidally disrupted. The main planetesimal appears to have a ~4.5 hour orbit, and we have already observed
multiple transits causing drops in flux in excess of 40% of the stellar flux with transit durations as short as 5 minutes.
Above: The duration of the transit events that we observe suggest that there are cometary tails trailing the disintegrating planetesimals in this system.
Figure from Vanderburg et al. (2015).
Above: A schematic of the trailing and leading cometary tails from the disintegrating planetesimal compared to the White Dwarf host size.
Figure from Vanderburg et al. (2015).
Above: Here is an artist's conception of what the main disintegrating planetesimal might look like. Image Credit: Mark Garlick.
Amateurs, undergraduates and/or other individuals with approximately 14-inch telescopes or larger may be able to help us observe WD 1145+017.
We are hoping to gather observers from around the world!
Above: Here is an example of amateur observations of WD 1145+017 using 14-inch and 16-inch telescopes by the amateurs Bruce Gary and Jerry Foote
on UT 2015 Nov. 21st.
Multiple decrements in flux are observed with depths up to 70% of the stellar flux!
Observers
should:
Filter choice: use a broad optical filter, V-band or a similar optical filter.
For smaller telescopes (~16" or less), observers should avoid nights when the moon is full, or when the moon is close in the sky to WD 1145+017.
Aperture photometry should be performed on the data (using at least three reference stars) and
the reduced light curves should be sent to the below e-mail address.
Please send your data in a text file using the following format:
"Julian Date, Target Star Magnitude, Ref Star #1 Magnitude, Ref Star #2 Magnitude, Ref Star #3 Magnitude".
Please also include the name of the observers and the location of the observation (including the
latitude and longitude of the observing site) in the body of the e-mail.
All individuals who submit light curves that are usable in the resulting scientific publication will be included as co-authors in the resulting scientific publication.
