Supernova 1999aa in NGC 2595

This page is devoted to information on Supernova 1999aa in NGC 2595. Basic information on this SN, including the last reported brightness, on this Supernova can be found on the main supernova page. Information on the original web pages for many of these images can be found on the Supernova links web page.

Supernova 1999aa was discovered simultaniously by several people. The first to report it was Ron Arbour or England, and was found while it was still brightening.

Web pages dedicated to this SN.

  • AUDE has a 1999aa page [Translate]
  • Jean Marie Llapasset has a 1999aa web page.
  • Kevin Krisciunas's Apache Point Observatory images page has extensive data of 1999aa.

    The following is a list of images of this SN, in chronological order. Click on the name in the "observer" column to see the image.
    If you know of any others, please tell me! DiscoveryComparison images
    Ron Arbour 2/11.0166/9915.5CCD
    CfA 2/12/99CCD
    Helmut Ullrich 2/12/99C TIFF version
    Jean Marie Llapasset 2/12/99 23h03m09s15.97CCD
    Jean Marie Llapasset 2/12/99 23h03m09s15.97CCDwith Star magnitudes
    Larry Robinson 2/13.34/9915.5CCD
    ND James 2/13.783/99CCD
    Jean Marie Llapasset 2/13/99 20h55m11s15.79CCD
    I.L.R.A. image 2/14/99C
    Alain Moisson 2/14/9915.66CCD
    Robert Kuberek 2/14/99 9:50 PSTC
    René Roy
    Blauvac Obs
    2/14/99 - 20h32m53s15.96CCD
    Jean Marie Llapasset 2/14/99 21h24m51s15.66CCD
    Hubert Lehmann 2/15/9915.64CCD
    Y. Sano 2/16.5647/9915.34CCD
    Pedro Ré 2/18/99 21:0615.3CCD
    Diego Rodriguez2/18.958/9915.00CCD
    Trisciani Damiano 2/19/99CCD
    Aldo Proietti 2/19/99 00.40 UT CCDSTARLIGHT XPRESS SXR-C 10x60 seconds
    Apache Point
    2/19/99 02:08:09 UT 13.82
    Robert Kuberek 2/20/99C
    Claude Boivin 2/21/99 00:32 UT14.9CCD
    Paul Pinel 2/22/99 - 21h22m03s15.27CCD
    Worth Hill image 2/22/99 21:49:44C
    Robin Chassagne 2/22/99 - 22h01m00s15.29CCD
    KenIchi Kadota
    Seiichi Yoshida
    2/23/99 01:44:11 JST 15.2CCD
    Kereszty Zsolt 2/23/99 CCD
    Juan Gonçalves
    Joăo Porto
    2/24/99 23:53 UT 14.76CCD
    Claude Boivin 2/25/99 01h10m00s 15.0C
    Jean Marie Llapasset 2/25/99 20h02m49s UT 15.11CCD
    Robin Chassagne 2/25/99 20:35 UT 14.86CCD
    Observatoire de Narbonne 3/2.8/99 15.2C
    Paul Pinel 3/3.9/99 15.49CCD
    Marko Moilanen 3/4/99 0.30 UT 15.0R
    KenIchi Kadota
    Seiichi Yoshida
    3/4/99 02:22:25 JST 15.8CCD
    G. Sala Undated CCDcolor
    Paul Pinel 3/6.9/99 15.65CCD
    Observatoire de Narbonne 3/7.8/99 15.6CCD
    Kereszty Zsolt 3/7/99 19:12 UT 16.4CCDMiskolc, Hungary
    Paul Pinel 3/12.0/99 15.96CCD
    Kereszty Zsolt 3/12/99 21:15 UT 15.3CCD
    Larry Robinson 3/14/99 CCD
    Paul Pinel 3/14.8/99 15.96CCD
    Paul Pinel 3/15.8/99 15.97CCD
    René Roy 3/15.81/99 15.99CCD
    Robin Chassagne 3/15.9/99 16.04CCD
    KenIchi Kadota
    Seiichi Yoshida
    3/16/99 21:48:52 JST 16.2C
    Paul Pinel 3/16.86/99 16.04CCD
    Observatoire de Narbonne 3/17.8/99 15.96CCD
    Paul Pinel 3/17.86/99 16.0CCD
    László L. Kiss 3/18/99 19:49 UT C
    Claude Boivin 3/18/99 02h15m00s 16.0C
    Observatoire de Narbonne 3/19.8/99 16.1CCD
    Observatoire de Narbonne 3/20.8/99 16.2CCD
    Paul Pinel 3/20.8/99 16.1C
    Observatoire de DAX 3/21/99 03h16m38s C
    Pedro Ré 3/22/99 20:03 UT16.01C
    Observatoire de DAX 3/30/99 03h16m38s C
    Paul Pinel 3/31.868/99 16.5C
    Paul Pinel 4/3.9/99 C
    Paul Pinel 4/8.8/99 C
    Paul Pinel 4/9.834/99 16.9C
    Pedro Ré 4/5/99 21:22 UT 16.7C
    Kopernik image 4/11/99 3:11 UT C
    Paul Pinel 4/11.4/99 16.9C
    Kereszty Zsolt 4/14/99 19:58 UT 17.0C
    Paul Pinel 4/29.4/99 17.5C
    Monte Gernelli Observatory Undated C

    Light curves and Spectra:

  • CfA Spectra
  • AUDE light curve
  • APO Light curve
  • APO Color curve
  • VSNET Light curve (requires JAVA).

    "The rise and fall of 1999aa" by Alessandro Dimai from Cortina Astronomical Association

    If you have observations of this Supernova, please send them to Use this VSNet data query to see what information has been reported so far. Other VSNet data on this SN:
  • [vsnet-chart 136] Chart of SN 1999aa
  • [vsnet-chat 1641] Host galaxy of SN 1999aa
  • [vsnet-alert 2628] SN1999aa brightening
  • [vsnet-recent 9002] SN1999aa latest
  • [vsnet-recent 9459] SN1999aa summary up to now
  • [vsnet-recent 12414] SN1999aa recent (cont'd)

    from [vsnet-alert 2617] SN 1999aa in NGC 2595
    Dear SN watchers,

    Mr. Ron Arbour, U.K. amateur astronomer, has discovered his third supernova in NGC 2595 on Feb. 11.02. Congratulations, Ron!

    According to IAUC 7108, the new star appears at R.A. = 8h27m42s.03, Decl. = +21o29'14".8 (2000.0), which is about 30" north from the bright core of the host galaxy NGC 2595. The host is an SBc galaxy nearly face-on, and SN 1999aa is just on the northern arm (ring?). (Images can be seen at Mr. Bishop's page: .)

      Reported magnitudes of SN 1999aa (from IAUC),
       1998 03        >17.5C  R. Arbour
       1999 02  5.3   >19C    KAIT
       1999 02 11.017  15.5C  R. Arbour,
    which tells that it would be on the brightening phase.  

    The spectroscopy has performed at Lick Observatory, which tells that this SN is peculiar one and resembles that of a peculiarly bright SN Ia 1991T about a week before maximum.

    From the recession velocity of the host (4400 km s-1, vsnet-chat 1641), the maximum of typical SNe Ia at this distance would be 15.5 mag or so, but 1991T was 0.5 -- 1 mag brighter than normal SNe Ia. Further magnitude estimates are greatly encouraged, which will provide a good tests for "brighter SN Ia has broader light curve" hypothesis.

    Sincerely Yours,
    Hitoshi Yamaoka, Kyushu Univ., Japan

    Back to Bright Supernovae - 1999.
    Back to Bright Supernovae.
    Back to Bright Supernovae - 1999
    David Bishop
    Last modified: Thu Dec 16 12:32:58 EST 1999