Flare Star Near WASP-1

Links internal to this web page

    Introduction
    Observers
    Analysis of flare event of 2007.10.15
    Non-flare observations
    Finder chart

Introduction

This web page displays lifht curves for the newly-discovered "flare star" located close to exoplaent WASP-1. It has the GSC designation 02265:00068.

The flare star coordinates are 00:21:12.40 +32:01:41.5. It is estimated to have the following magnitudes (based on J = 10.414, K= 9.705): B = 13.5, V = 12.4, R = 11.8, I = 11.26, B-V = 1.13, J-K = 0.709. The star is very red, and if it's on the main sequence it would have a spectral type of about M1 (based on the J-K color). This is a typical spectral type for flare stars.

There's nothing in the x-ray or radio source catalogs at this star's location.

The flare star's behavior was first noted by Bruce Gary (GBL) who notified Cindy Foote to check her LC (since she observed the same WASP-1 transit). Cindy found the flare star with the same behavior as GBL. Cindy notified two others who she knew had observed the same WASP-1 transit and both of them also found the same flare star behavior. It is fortuitous that four observers were monitoring exoplanet WASP-1 on 2007.10.15 when the nearby star flared, so there is no doubt that the star really flared, given that all four light curves for the flare star show the flare occurring at the same time, with the same brightening and same decay shape.

Observations by two observers at other times than the flare event show no flare feature or other activity. So far this star has been observed for a total of 26 hours and only one flare has been observed.

Observers

    Cindy Foote (FCN), Utah, 24-inch
    James Carlisle (CJH), California, 14-inch
    Thomas Smith (STHO), New Mexico, 14-inch
    Bruce Gary, (GBL), Arizona, 14-inch
    Edwin Sheridan (SEE), Utah, 14-inch

ANALYSIS OF FLARE EVENT OF 2007.10.15


All 4 LC observations for the flare event.



The flare star was fading at ~2 mmag/hour before and after the flare event. When the brightening occurred (06.72 UT) it was abrupt (<30 sec) and reached ~0.34 mag. The fade had an exponential decay time of ~12 minutes. All 4 observers show the same shape flare event.

FLARE EVENTS

2007.10.15 Flare Event

 So far all R-band observations of the flare event of 2007.10.15 show a brightening of ~0.25 mag.


Excellent LC using a 14-inch Meade RCX400.






Zoom of previous graph showing stability of nearby check stars while the flare star is slowly fading throughout the brief flare event.

NON-FLARE OBSERVATIONS

2007.10.20 No Flare Event



2007.10.18 No Flare Event 



FINDER CHART


Cindy Foote's finder chart showing star mags & colors. Star #9 is the flare star.



This site opened:  October 21, 2007.  Last Update:  October 23, 2007 (UT)