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MisV1445 : Possible Real-Time Flare Detection     2012 Jan. 9 Seiichi Yoshida / MISAO Project On December 17, 2011, we discovered a rapid-brightening star from the survey images taken by Youichirou Nakashima in the course of the MISAO Project. It is possible real-time flare detection of a new flare star. Recent Observations (Updated on Oct. 6, 2012) Recent Images (Updated on Jan. 9, 2012) The possible flare occured on a star in Taurus, USNO-A2.0 1125.02693028. It is normally fainter than 16 mag, but brightened up to 14.7 mag in outburst on Dec. 17. It is not a known variable star. So it will be a new flare star. We the MISAO Project assigned a new variable star designation MisV1445 to this star. Brightening of MisV1445 (Image: Youichirou Nakashima) Field of view: about 12.5 arcmin. This flare star was discovered by Seiichi Yoshida (MISAO Project) in the MISAO Project nova survey. It was picked up as one of the nova candidates from Youichirou Nakashima (Okayama, Japan)'s unfiltered CCD images on 2011 Dec. 17 by the PIXY System 2. The astrometry from Nakashima's images is: R.A. 05h41m30s.52, Decl. +22o39'27".4 (equinox J2000.0). MisV1445 was in the frame of 4 images on Dec. 17. The star is not visible on the first image, visible but faint on the second image, and bright on the third and fourth images. It brightened rapidly by 2 mag or more withiin only 4 minutes. Date and Time (UT) Magnitude Dec. 17.76277 (18:18:23) fainter than 16.8 Dec. 17.76411 (18:20:19) 15.8 Dec. 17.76545 (18:22:15) 14.7 Dec. 17.76678 (18:24:10) 14.8 MisV1445 was not detected on our past images, 5 nights between January and November in 2011 by Nakashima, or 2000 February by Nobuo Ohkura (Okayama, Japan). It was fainter than 16.5-17.4 mag. Date Observer Magnitude 2011 Nov. 23 Nakashima fainter than 16.9 2011 Feb. 22 Nakashima fainter than 16.8 2011 Feb. 3 Nakashima fainter than 16.8 2011 Jan. 26 Nakashima fainter than 17.3 2011 Jan. 10 Nakashima fainter than 17.4 2000 Feb. 26 Ohkura fainter than 16.5 Instruments: Youichirou Nakashima -- Canon 500-mm f/4.5 camera lens + SBIG ST-8 Nobuo Ohkura -- 0.16-m f/3.8 Wright-Schmidt reflector + SBIG ST-8(ABG) Yoshida noticed this flare event soon after midnight on Dec. 23 (JST). Nakashima and Masayuki Suzuki observed it soon for confirmation. But MisV1445 has already faded, and we could not confirm the flare event. Date Observer Magnitude 2011 Dec. 22 Nakashima fainter than 17.0 2011 Dec. 24 Suzuki 18.0 Instruments: Youichirou Nakashima -- Canon 500-mm f/4.5 camera lens + SBIG ST-8 Masayuki Suzuki -- GRAS-017 0.43-m f/6.8 + FLI ProLine E2V CCD47-10-1-109 Deep Depletion Fused Silica (Near-IR) The original image files of the flare event on Dec. 17 can be downloaded here (SBIG format). MisV1445 is visible at different (x,y) position on three images. So the brightening seems to be a real event. Date and Time (UT) Magnitude (x,y) Position Original Image Dec. 17.76277 (18:18:23) fainter than 16.8 (65, 783) Download Dec. 17.76411 (18:20:19) 15.8 (500, 769) Download Dec. 17.76545 (18:22:15) 14.7 (935, 753) Download Dec. 17.76678 (18:24:10) 14.8 (1370, 735) Download Here is the data of MisV1445 recorded in the USNO-A2.0 catalog. USNO-A2.0 1125.02693028 R.A. 05h41m30s.523 Decl. +22o39'26".96 Mag(R) 17.9 Mag(B) 19.7 Masayuki Suzuki researched the USNO-B1.0 catalog. Here is the data of MisV1445 recorded in the USNO-B1.0 catalog. USNO-B1.0 1126-0102137 R.A. 05h41m30s.51 Decl. +22o39'26".8 Mag(B1) 20.31 Mag(R1) 17.26 Mag(B2) 19.81 Mag(R2) 18.15 Mag(I) 15.77 A large flare tends to be observed on a nearby red dwarf. The color recorded in those star catalogs coincides to that. However, the proper motion of MisV1445 is 0 milliarcsec/year in the USNO-B1.0 catalog. It may suggest that MisV1445 is not a nearby star. Recent Observations (Updated on Oct. 6, 2012) 2012 Sept.26.72622 [15.4 C Youichirou Nakashima 2012 Sept.26.72617 [16.5 C Youichirou Nakashima 2012 Sept.26.72486 [15.3 C Youichirou Nakashima 2012 Sept.26.72481 [16.3 C Youichirou Nakashima 2012 Sept.26.72351 [15.4 C Youichirou Nakashima 2012 Jan. 30.52269 [13.8 C Nobuo Ohkura 2012 Jan. 30.52130 [13.8 C Nobuo Ohkura 2012 Jan. 30.51991 [14.0 C Nobuo Ohkura 2012 Jan. 17.912 18.26 CV Diego Rodriguez 2012 Jan. 17.910 17.76 CR Diego Rodriguez 2011 Dec. 25.74111 [16.7 C Youichirou Nakashima 2011 Dec. 25.73977 [16.8 C Youichirou Nakashima 2011 Dec. 25.73843 [17.1 C Youichirou Nakashima 2011 Dec. 24.02728 18.0 C Masayuki Suzuki 2011 Dec. 24.02542 18.0 C Masayuki Suzuki 2011 Dec. 24.02356 17.9 C Masayuki Suzuki 2011 Dec. 22.80984 [16.9 C Youichirou Nakashima 2011 Dec. 22.80851 [16.9 C Youichirou Nakashima 2011 Dec. 22.80716 [17.0 C Youichirou Nakashima 2011 Dec. 22.80582 [17.0 C Youichirou Nakashima 2011 Dec. 22.76007 [17.0 C Youichirou Nakashima 2011 Dec. 22.75874 [16.6 C Youichirou Nakashima 2011 Dec. 17.76678 14.8 C Youichirou Nakashima 2011 Dec. 17.76545 14.7 C Youichirou Nakashima 2011 Dec. 17.76411 15.8 C Youichirou Nakashima 2011 Dec. 17.76277 [16.8 C Youichirou Nakashima 2011 Nov. 23.65544 [16.7 C Youichirou Nakashima 2011 Nov. 23.65410 [16.3 C Youichirou Nakashima 2011 Nov. 23.65277 [16.9 C Youichirou Nakashima 2011 Nov. 23.65142 [16.9 C Youichirou Nakashima 2011 Feb. 22.48969 [16.5 C Youichirou Nakashima 2011 Feb. 22.48836 [16.7 C Youichirou Nakashima 2011 Feb. 22.48701 [16.8 C Youichirou Nakashima 2011 Feb. 22.48568 [16.6 C Youichirou Nakashima 2011 Feb. 3.57182 [16.7 C Youichirou Nakashima 2011 Feb. 3.57046 [16.8 C Youichirou Nakashima 2011 Feb. 3.56911 [16.8 C Youichirou Nakashima 2011 Feb. 3.56775 [16.7 C Youichirou Nakashima 2011 Jan. 26.54955 [17.1 C Youichirou Nakashima 2011 Jan. 26.54821 [17.1 C Youichirou Nakashima 2011 Jan. 26.54685 [17.3 C Youichirou Nakashima 2011 Jan. 26.54550 [17.1 C Youichirou Nakashima 2011 Jan. 10.59742 [17.2 C Youichirou Nakashima 2011 Jan. 10.59606 [17.4 C Youichirou Nakashima 2011 Jan. 10.59471 [17.3 C Youichirou Nakashima 2011 Jan. 10.59336 [17.1 C Youichirou Nakashima 2000 Feb. 26.55448 [16.2 C Nobuo Ohkura 2000 Feb. 26.55264 [16.5 C Nobuo Ohkura

Recent Images (Updated on Jan. 9, 2012) 2011 Dec. 24 09:32:56 UT (120 sec) Masayuki Suzuki GRAS-017 0.43-m f/6.8 + FLI ProLine E2V CCD47-10-1-109 Deep Depletion Fused Silica (Near-IR) Field of view: 16' x 16' * North is left.