Potential transient

• by karthikeyan.d

  The orange object is seen only here (GAMA) and in DECaLS-DR3. It is not seen in PanSTARRS, SkyServer, SDSS2 and Aladin Lite. See the object discussion page for image links and other details.

  I am trying to find the dates of the different images. Any idea how to find it?

  Should this be reported to the TNS (https://wis-tns.weizmann.ac.il/)?

  Posted September 16, 2017 5:34 AM

• by Budgieye moderator

  Does anyone know how to get the KiDS date?

  KiDS taken between 2011 and 2017

  KiDS http://kids.strw.leidenuniv.nl/index.php

  http://kids.strw.leidenuniv.nl/DR2/data_table.php

  I think it is a supernova, but blue -green filter image taken at a different time when it wasn't as bright, so it looks red?

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  DECaLS April 7, 2015

  http://legacysurvey.org/viewer/jpeg-cutout/?ra=175.1490&dec=0.8538&zoom=14&layer=decals-dr3

  http://legacysurvey.org/viewer?ra=175.1489&dec=0.8545&zoom=16&layer=decals-dr3

  made of 6 images, data obtained by right clicking on image, blue (g) and green(r) filters taken at different times.

  decam 392812 N25 g CCD decam-392812-N25-g, image decam/CP20141227/c4d_141229_063344

  decam 511427 S27 g CCD decam-511427-S27-g, image decam/CP20160107/c4d_160115_051517

  decam 392807 N25 r CCD decam-392807-N25-r, image decam/CP20141227/c4d_141229_062519

  decam 511428 S27 r CCD decam-511428-S27-r, image decam/CP20160107/c4d_160115_051630

  decam 430276 N25 z CCD decam-430276-N25-z, image decam/CP20150407/c4d_150407_233832

  decam 430287 S27 z CCD decam-430287-S27-z, image decam/CP20150407/c4d_150407_235906

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  Pan-STARRS 2010-2014

  http://ps1images.stsci.edu/cgi-bin/ps1cutouts?pos=175.14928239%2C0.8544&filter=color&filter=g&filter=r&filter=i&filter=z&filter=y&filetypes=stack&auxiliary=data&size=240&output_size=0&verbose=0&autoscale=99.500000&catlist=

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  The 3 colours in SDSS are taken within a few minutes of each other. This is not true for other surveys.

  http://www.galaxyzooforum.org/index.php?topic=437.msg39416#msg39416

  Here is a modified Julian date converter

  http://pdc.ro.nu/mjd.cgi

  Put the number into the Julian, read off the Gregorian, which is what we use

  Index for Galaxy Zoo Talk Other data sources https://talk.galaxyzoo.org/#/boards/BGZ0000001/discussions/DGZ0000wrb?page=6

  SDSS dr14 April 20 2007
  04/20/2007

  http://skyserver.sdss.org/dr14/en/tools/explore/Summary.aspx?id=1237674651537178857

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  SDSS dr7 April 20, 2007

  http://cas.sdss.org/dr7/en/tools/explore/obj.asp?id=587748930312274099

  Posted September 16, 2017 6:24 AM

• by bluemagi

  Hi, I am not sure but could it possibly be a variable star?

  Posted September 16, 2017 9:40 AM

• by Budgieye moderator

  I had wondered if it were a red nova as a foreground star in our galaxy (like the one that will happen in several years) or a flaring red dwarf. Somehow I should think that we should see something in SDSS.

  

  http://skyservice.pha.jhu.edu/DR9/ImgCutout/getjpeg.aspx?ra=175.1489&dec=0.8545&scale=0.049515875&width=512&height=512&opt=G&query=&Grid=on

  Red nova in 2022 https://talk.galaxyzoo.org/#/boards/BGZ0000008/discussions/DGZ0002a82

  Forum: Cataclysmic red dwarf star http://www.galaxyzooforum.org/index.php?topic=279787.msg575925#msg575925

  Posted September 16, 2017 10:15 AM

• by bluemagi

  I don't know but I was thinking of something like Eta Carina for some reason. It can really flare up and then decrease.

  Posted September 16, 2017 10:20 AM

• by Ghost_Sheep_SWR

  It is only visible in VSTKIDS r band (strong detection) which is mapped to red / orange for Galaxy Zoo subject image. So the red color is actually a bit misleading since we are used to SDSS gri images with r band mapped to green.

  Here are two VST KIDS gri images with r band mapped to green:

  

  Haven't been able to decipher how to get obsdate or FITS files from ESO / VST, might be necessary to first create an account or something.

  But detection in DECaLS rules out an artifact, and also present in / near a galaxy makes it almost certainly a supernova or similar transient event AFAIK (apart from coincidental positioning ofcourse).

  Posted September 16, 2017 2:50 PM

• by Budgieye moderator

  Good point. I feel much more comfortable with a green supernova, even though I know green in SDSS is actually red. 😃

  Explanation of colour for anyone totally confused by the last sentence.

  Spectra guide for SDSS images in Galaxy Zoo Talk https://talk.galaxyzoo.org/#/boards/BGZ0000001/discussions/DGZ0000ulp?page=3&comment_id=53fef2ee3d5a77490c0001b6

  Posted September 16, 2017 9:40 PM

• by Ghost_Sheep_SWR in response to Budgieye's comment.

  Oh yeah that is SO confusing, I'm happy that I can remember r band is gReen, i band is red so naturally g band is blue. SDSS gri = blue green red.

  Now don't look at this too long or your brain might explode 😉 SDSS real color wavelenghts vs. mapped colors

  

  Posted September 16, 2017 9:50 PM