Showing posts with label Nova. Show all posts
Showing posts with label Nova. Show all posts

Wednesday, January 22, 2014

Supernova 2014J in M82 - Super Stuff!

Well its Supernova Week! There's science going off everwhere! Why watch endless hours of Sci-fi when you can watch stars blowing up live!

After last week's excitement of a nice Type IIn supernova in NGC 3448, there is breaking news tonight with a bright Supernova going off in M82.

Image Credit: P.Lake H06 0.5m f/4.5 Planewave +CCD

UPDATE 3: Clint Whittaker iTelescope member photographed SN 2014J on the 15th of Jan at 16:40 UT.

Image Credit: C. Whittaker

UPDATE 2: A careful review of some of the iTelescope.net's member images of M82 show the brightening commenced sometime between 13th and 15th of January. The earliest image of this event now stands at 2014 01 15.571 by K Itagaki from an earlier survey. I have added a link to the discovery circumstances (below) - What a story that is, they'll be dining out on that for years.

UPDATE 1: It looks like Fraser Cain's Virtual Star Party photographed the SuperNova back on Sunday night US time, not realising it at the time. Tom Nathe broadcast a live photo of M82 into the Virtual Star Party with the Supernova clearly in view, but operating under the pressure of a live broadcast, didn't realise it at the time.

As usual the iTelescope.net community has been involved in prompt follow up action with the on-demand telescopes swinging into action.

So what's going on, how does all this happen, what are the reporting processes involved and how do Amateur Astronomer's make a contribution. All good questions!

Stars blowing up are more common that you think. Whilst the mainstream media usually only pick up on a couple of Supernovae per year (usually the bright ones in well known galaxies), astronomers detect over 400 novae each year, which is more than one per day. Amateur astronomers make a significant number of these discoveries, and several teams have developed advanced techniques, processes and teamwork to systematiclly go after these interesting events.

One great leader in this area of the amateur community is the BOSS team (Backyard Observatory Supernova Search) who have discovered 83 supernovae, one of which has rocked the astronomy community and resulted in the Hubble Space Telescope being swung into action for follow up measurements. Other regulars are a dedicated group of Japanese astronomers who hardly miss a trick: Koichi Itagaki, Meineko Sakura, Seiichiro Kiota (and their teams - appologies for not mentioning everyone), do great work. On the 14th January Mr Itagaki discovered a Supernova in NGC 3448. Well known amateur astronomer Patrick Wiggins also photographed it independently, quite by chance, without a targeted search. I assisted Patrick with his follow-up images, and Patrick later found Mr Itagaki was awarded the discovery as he had an earlier image from the night before.

Image Credit: P.Lake H06 0.5m f/4.5 Planewave +CCD

Many of these dedicated teams have advanced scripting techniques with systematic searches that can cover up to 200 galaxies per night. The 6 members of the BOSS team also leverage the time zones from New Zealand, to the east coast of Australia, and across to the west coast of Australia. Each part of the team performs different steps, photographing, processing, researching, following up and reporting. They have built strong partnerships with professional observatories who provide the spectral analysis, to quickly identify the supernova type. The BOSS team pride themselves on having never having submitted a false-positive report.

Using a sophisticated DSLR camera on a tripod and subtracting images from night to night, comparing the differences, is another method used by amateur astronomers. This is surprisingly effective method for transient nova in the southern hemisphere.

Tonight's discovery of the supernova in M82 was reported to the Central Bureau for Astronomical Telegrams [CBAT] by S.J Fossey and his class of students it was confirmed by Seiichiro Kiota and followed up by the MASTER Team in Russia, and Leonid Elenin from the ISON Team. The MASTER team are also great leaders and made 210 transient (includes supernova, nova) discoveries in 2013.

So if I am photographing a galaxy and think I can see something different, what should I do, how do I check, who do I tell, if I think I might have found a Supernova/Nova event?

Step 1 - Re-photograph the area and check for asteroids and or artifacts in your image

Step 2 - Check a previous known image of the same area and compare to make sure nothing was there previously. You need to be careful doing this as other images may have a different orientation to your's depending on the Position Angle of the camera they were taken with. It may be flipped horizonally and vertically to your image. One such site where you can get easy access historical images is the CDS (Centre de Données astronomiques de Strasbourg) Portal which has a searchable web interface for various star Catalogs (just enter the exact RA and Dec).

Step 3 - Once you believe you have something - alert some of your collegues and get them to obtain some confirmation images.

Step 4 - Report to CBAT with the exact postion to the nearest arc-second with an estimate of the magnitude and your location, telescope details, and discovery circumstances (eg PSN J09554214+6940260 where "Possible Super Nova" is RA is 09 55 42.14 and Dec +69 40 26.0).

Step 5 - Wait and hope you are the first in - but you'll have to be quick ;-) Its always a great idea to get someone to check your work so you avoid embarrassing mistakes.

Step 6 - Then sit back and wait for other astronomers with spectroscopic capabilities to confirm the Supernova type by assessing which Balmer Lines are present in the spectrum.

Even though you might not hear about every supernova, this is a vibrant area of constant research that creates great excitment through the thrill of the chase for amateur astronomers and professionals around the world.

Saturday, September 26, 2009

When you wish upon a star

Welcome. This week has been characterised by some fairly average weather. Those of you tuning into Australia's premier football event around the world this afternoon will see plenty of our famous Melbourne weather on show.

Weather can have an impact on an observing campaign, so there have been some challenges in obtaining some of the data I have been chasing this week. I am getting great positive feedback on the blog - largely because I am blogging on my observations.

So this week, given the weather, I thought it would be good to talk about observation campaigns. This week I have barely jagged a couple of short sessions on
V4743 SGR and some of the surrounding variables in the same field. V4743 Sgr is also referred to as Nova Sgr 2002c making it an object of some interest, given its nova outburst in 2002. Over 200 observers have contributed to the AAVSOs lightcurve.



So what is it that makes an object "interesting"? Clearly a Nova outburst is something that is interesting, as professional astronomers are quick to follow up with highly accurate spectroscopy. The advantage of having amateurs "on their toes" and participating in regular campaigns is that professional astronomers can't afford to have billion dollar telescopes pointed at stars, waiting for years, for something to happen. (The hubble deep field shot is a noteable exception...but a deliberate experiment to look at nothing to see if something WAS there)

A good example of leveraging the skills of amateur astronomers is my data here on QU Sgr. This is a Mira variable star of little or no interest to anyone.....but who knows one day it may be significant or do something. If that ever happened, what would we have to compare it with? So whilst gathering some data on V4743 with my set up which has a fairly large field of view, it is important to grab a couple of readings on any other Variables in the field, as other observers are unlikely to ever go specifically to QU Sgr to collect data.



There are a plethora of variable stars requiring regular observations and a limited number of observers. Today we have the fantastic use of social networking, blogs, forums and membership of organisations such as AAVSO. In this environment connected communities of dedicated amateurs have organised campaigns based on a prioritised list of "interesting objects".

Rod Stubbing who discovered this months outburst of VX For was working through a carefully targeted list of variables that were "in season" ie at an optimal position in the sky for observing. Rod indicated to me it was his first observing session on VX For for the year. So you never know what you will find, and how many other people who are observing.



So I leave you this week with the completely insignificant Mira Variable QU Sgr that noone else has reported on for over 4000 days.

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