Calling all astrophotographers!
In October, a star in Cassiopeia brightened suddenly. It brightened from magnitude 11.5 to 7.5, a factor of about 40. The star was not the type known to do this, so astronomers are puzzling over it. It might have been a microlensing event, where the gravity of an object between us and the star acts like a lens, amplifying the star’s light. This would be an extremely rare and fantastically cool event, so if you have any images of the constellation taken in October, please see that link above. You can also contact the American Association of Variable Star Observers.
I went online to the Digitized Sky Survey and created this image of the star in question, GSC 3656-1328 (field of view = 0.5 degrees, coordinates = 00 09 22, +54 39 44 (2000)):
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Almost any wide field picture of the constellation may be helpful (the star is in the western part). If you have one, post a comment below. If you have one online, post a link! Also, you can post images to the Bad Astronomy and Universe Today bulletin board. That’s a great place to see other images and talk about them. You should check it out if you have Cassiopeia pix or not!
Tip o’ the dew shield to DaveP’s Astronomy.
November 29th, 2006 at 1:12 pm
This is very interesting: to what extent are (professional) astronomers scouring the heavens for these anomalies? Is it automated?
November 29th, 2006 at 3:50 pm
Professional astronomers spend some of their time on the kinds of surveys that would turn up things like this, but it could be said that pro-am astronomers are the ones who really run with it.
A pro-am astronomer could be the kind of person who owns a large computerised telescope and takes professional-grade images with an interest in collaborations with academics, but does it without the standard forms of academic funding.
Academic astronomers don’t often have the time to just survey the sky in search of random events. They are more interested in targeted searches for things that are already known.
The Puckett Observatory Supernova Search is one of these groups, and TBA has featured Tim Puckett before. I have helped Tim in codiscovering a supernova, a variable star outburst and a “variable object” myself.
November 29th, 2006 at 4:19 pm
This object was bright enough that a lot of amaeturs must have caught it. Most pros, as Eric said, don’t do wide-angle stuff.
There are asteroid searches that are wide field, and other surveys, but they would have had to catch this at just the right time. It’s far more likely that someone was just trying to get a pretty picture on, say, October 29, and that image will be very valuable scientifically.
November 29th, 2006 at 4:30 pm
I’ve got some photos of Cassiopeia. I don’t think they’d be of much interest, though, since she’s my cat. (But if she became brighter by a factor of 40, we’d be in deep trouble.)
November 29th, 2006 at 7:40 pm
Links not working for me. Anyone else having a problem?
November 29th, 2006 at 7:54 pm
So neat! If it is a lensing event, I wonder what it might be that got between us and the star. Rampant baseless speculation is good for the soul?
November 29th, 2006 at 7:56 pm
Phil,
Have you contacted Joe Patterson who runs the Center for Backyard Astronomy? Joe has his amateurs concentrating on cataclysmic variables and I’m trying to remember if one of the October targets was in Cassiopeia (I do remember him having a Cassiopeia target but can’t remember what month).
November 30th, 2006 at 3:14 am
Phil, just wanted to say thanks for helping to raise the profile of this request. Greatly appreciated.
November 30th, 2006 at 10:40 am
Argh! I’d go out and take some photos of it, but my observatory is locked up tight these days. We just broke the all time record for rain in November here in Seattle. I haven’t seen the sky for over a month…or at least enough to justify opening the observatory roof.
*sigh*
Tom
–suffering from astronomy withdrawal in Seattle
November 30th, 2006 at 12:59 pm
[...] Met de laatste zinssneden uit Polen gingen uiteraard menig harten kloppen bij amateur-sterrenkundigen. Er zou voor het eerst microlensing door amateurs kunnen zijn waargenomen. Bij gravitationele microlensing wordt een zwak object in helderheid vergroot als er tussen het object en de Aarde een ander zwaar object komt. Dat zware object zal door z’n gravitatie de lichtstralen van het zwakke objecten afbuigen, zodat deze gebundeld en versterkt worden en zodoende neemt de helderheid toe. In het geval van GSC 3656-1328 wordt er zelfs gesproken van een mini-zwart gat dat verantwoordelijk zou zijn voor de gravitationele microlensing. Toetsing van deze hypothese zou kunnen door de lichtcurve van de ster te bekijken na het maximum én voor het maximum. De lichtcurve moet namelijk symmetrisch zijn. Probleem is echter dat de ster voor de 31e oktober niet uitgebreid is gefotografeerd! Kortom, de amateur-wereld is hevig op zoek naar foto’s van de ster van voor 31 oktober 2006. Iedereen met dergelijke foto’s kan ze mailen naar Roger Pickard van de VSS in Amerika. Op 6 november kwam overigens een telegram (bestaan die nog?) waarin het CBAT meldde dat het ook zou kunnen gaan om een zogenaamde dwergnova. Afijn, hier valt nog veel over te melden. Ik hou jullie op de hoogte. Bron: Society for Popular Astronomy en Bad Astronomy Blog. [...]
November 30th, 2006 at 9:09 pm
Correction: Those dates are the dates I uploaded the images to flickr.
They were actually taken on Sep 30, Oct 12, and Oct 28, respectively.
January 10th, 2007 at 11:15 am
i am studying cassiopeia right now and i got a lot out of this website, it really helped me on my project, i got a 98. and this is the website that i came to everyday, thanx to whoever put this together it really helped me…thanx a million.
January 10th, 2007 at 11:23 am
That’s great Chelsea! I’m glad we could help!
June 18th, 2007 at 7:21 am
A paper on this event is available at http://arxiv.org/abs/astro-ph/0703125 . The conclusion is that it is a microlensing event.