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Archive for September, 2011

Ever seen the Zodiacal Light ?

September 29, 2011 Leave a comment

No, me neither until this morning. I was reading Bob Kings excellent Astro Bob astronomical blog http://astrobob.areavoices.com/ and the entry for yesterday happened to discuss the autumn phenomena called the Zodiacal Light http://astrobob.areavoices.com/2011/09/28/comet-honda-visits-the-ghost-of-comets-past/  This faint, low,  roughly triangular glow of light, best seen in the east just before morning twilight, represents the reflected light from cosmic dust which has gathered on the ecliptic plane. The ecliptic plane is slightly tilted upward at this time of year which makes it more visible, particularly when the moon is absent. This interplanetary dust lies in a lens shaped band centered around the sun and extending out beyond Earth’s orbit. The dust is commonly thought to derive from the trail of comets passing through the solar system. I had a look this morning and there was certainly a very faint and high glow extending up at least 45 degrees into the sky when looking east around 6-6.30 am. I didn’t have the DSLR with me at the time but later on I thought I would have a look at the fisheye weather cams for the GRAS telescope in New Mexico and sure enough a faint triangular glow in the east was clearly discernible. Take a look at the image below and if you can see a faint wedge of light shooting up above the pole at the bottom of the image toward the Milky Way – that is the Zodiacal Light !

Categories: Comets, General

Massive Sunspot AR11302

September 27, 2011 Leave a comment

Sunspot AR11302 is a true behemoth at 150,000 km in length. It was crackling with B and C class flares today after calming down somewhat from its release of two X Class flares on the 22nd and 24th September. The spot is now facing Earth and if it releases any more high energy flares in the next couple of days we could see some spectacular aurorae down here around midnight in northern latitudes. Seeing conditions were extremely poor during imaging with a lot of atmospheric turbulence so these images don’t really do justice to the amount of finely structured features that were on view today.

80mm PST Mod Ha view:

CaK PST view:

80mm PST Mod Ha view with bright C Class flare activity in AR 11302:

 

Categories: Solar

The other Double Cluster – NGC 884 and NGC 957

September 26, 2011 1 comment

Most people are familiar with the spectacular view of the main Double Cluster located in Perseus which consists of the bright open clusters NGC 884 and 869 lying some 7300 light years distant. This jewelled duo shining at magnitudes 6.1 and 5.3 are easily  resolved in a moderate 3″ telescope, but binoculars will also provide a nice view and you can even see the cluster as a faint sparkling smudge of light with the naked eye on a clear night in a dark location. While images of this cluster can be found in every coffee table book and all over the web I thought it might be fun to try something a little different when I realised that the nearby NGC 957 would just fit into the view along with NGC 884, providing an alternate double cluster. For this image I used the GRAS20 Tak 106 FSQ in New Mexico which has a nice widefield view capable of comfortably framing both clusters. The image is a 600 sec unbinned one-shot colour exposure centred on RA: 02h 20m 59.0s DEC: 57° 09′ 30″ (J2000)

I wonder how many more images containing two or more open clusters found in our galaxy can actually be imaged in one frame ? Only one other springs immediately to mind for me and that is the M35/NGC 2158 combination in Gemini which I imaged back in 2008 with my Equinox ED80 and a Canon 350d DSLR (see below) . If you can think of any more do let me know via the blog !

NGC 957 (top left) and NGC 884 (right) :

Another double! M35 (bright blue stars) & NGC 2158 (tight yellowish white cluster bottom left):

Categories: Stars & Star Clusters

Comet C/2009 P1 Garradd

September 18, 2011 Leave a comment

I revisited Comet C/2009 P1 Garradd last night on its journey through the region between Aquila and Hercules courtesy of the GRAS G3 telescope (Takahashi TOA 150/SBIG ST 2000XCM) in New Mexico. This observatory has been plagued by cloud and rain for the last two weeks, but before the moon rose at 9.30 pm last night (NM time) the sky was gloriously clear so I took the opportunity to reserve some time on the one-shot colour camera. The image below is the result of just a 5 minute exposure and shows the coma and faint gas tail glowing the characteristic blue-green of cyanogens and diatomic carbon which are fluorescing in the sunlight. C/2009 P1 appears to be around magnitude 7.0 now and should continue to brighten slowly through to February 2012 when it will reach its peak magnitude of 6.0 and may become visible to the naked eye. The two bright stars on the right side of the image are HIP 91205 (top – mag 7.75) and HIP 91169 (bottom – mag 8.60). Image taken 17/9/2011  9.24pm (New Mexico time) RA: 18h 37m 13.0s DEC: 19° 52′ 17″ (J2000)

 

Categories: Comets

Comet 213P Van Ness now fading in Pisces

September 17, 2011 Leave a comment

Comet 213P Van Ness is passing high through Pisces at the moment and currently hovers at around magnitude 14.4. It will fade slowly through to the end of the year when it will be 16.5. During August and early September fragments of the nucleus were seen to break away, effectively forming three short-lived magnitude 20-21 child comets named 213P B,C and D. These fragments have faded dramatically now and may no longer exist. Below is a quick 5 minute exposure with the Spanish GRAS 07 17 ” planewave in rather poor light conditions with the moon about 60 degrees away to the south. The very faint tail (easily seen in August) extends to the top right. This is quite an interesting and rarely visited part of the sky with a number of very faint fuzzies in the wider original image that defy identification in my planetarium software, which only extends to magnitude 18. Loads of nice double stars in this area too! Image taken 1.02am 17/9/11 RA: 22h 49m 38.0s DEC: 04° 32′ 09″ (J2000)

And the negative image…..

Categories: Comets

M51 Whirlpool Galaxy Supernova 2011dh

September 10, 2011 Leave a comment

As I mentioned in my last post supernova 2011dh is still visible in the Whirlpool Galaxy (M51) with the aid of a telescope. Magnitude is currently around 14.8 and fading so there’s still time to catch this one. I used the GRAS G07 17″ Planewave to capture an image tonight, but even though the moon is 116 degrees away to the south there was significant moonglow and this created a pretty horrible gradient across the image which could not be edited out using the usual gradient and light pollution removal tools. I therefore turned the image negative and increased the contrast to bring out some detail. The supernova is clearly visible at the marked location.

Here’s the current AAVSO light curve for this supernova…….

Comet C/2010 G2 Hill and update on SN 2011fe in M101

September 9, 2011 Leave a comment

During the early morning of 7th and 8th September I attempted to image Comet C/2010 G2 Hill which is very faint at approx mag 11 close to Lynx. On both occasions there were significant guiding errors with GRAS G7 in Spain which produced some very odd star trails. The comet only reaches a sufficient height for imaging on the GRAS telescopes after about 6.00 am Spanish time when the comet reaches 40 degrees above the horizon, so there may be some early twilight effects at play here.  GRAS telescopes generally cannot image below 30-35 degrees and atmospheric aberrations will be high below this level anyway.

The image below has been significantly cleaned up with all of the star trails removed. C/2010 G2 Hill appears as a faint smudge in the centre with a small diffuse coma. The comet is currently slowly brightening and should be visible in telescopes well into next year. GRAS G7 – 600 sec Lum/Deep Space Planewave 17″/FLI ProLine PL11002M

The supernova SN 2011fe in M101 (Pinwheel Galaxy) seems to have reached its maximum magnitude at around 10.0 or 9.9 according to the light curve provided on AAVSO. If you are thinking of imaging the galaxy now would be the best time !  Don’t forget that supernova SN 2011dh is still visible for imaging in M51 (Whirlpool Galaxy) too, but you will need to catch M51 early after sunset as it dips below 30 degrees altitude and into the murk by 10pm in the northern hemisphere. The current magnitude of SN2011dh in M51 is around 14.8

AAVSO light curve for SN 2011fe 9/9/11

M101 Supernova 2011fe and Comet C/2009 P1Garradd 4-9-11

September 5, 2011 Leave a comment

So last nights attempt to capture remote images of the supernova in M101 and Comet C/2009 P1 Garradd proved completely abortive! GRAS in New Mexico was completely clouded out all night and so was Spain until early morning. Having stayed up until 3.30am to make sure I caught M101 before it got too low in the sky I figured I would switch to the Spanish telescopes where Stellarium was telling me that M101 was visible around 4am. This proved to be incorrect due to a glitch with the timezone settings in Stellarium and the telescopes could not find the object – so I had nothing to show for a sleepless night !

Tonight was an altogether different scenario. I double checked where I had gone wrong with Stellarium and corrected the error. It showed I had a narrow window of opportunity between 8.00 and 8.45pm where I could image M101 before it dipped below the critical 40 degrees in azimuth where the telescopes in Spain cannot image due to the height of the surrounding walls in the observatory. The observatory went live around 8.15 pm so I logged onto the GRAS 7 telescope which is a Planewave 17″ imaging with an FLI ProLine PL11002M camera and set up for 15 mins of Luminance, bin 1, in 300 and 600 second exposures. At the same time I logged onto GRAS 16 and imaged C/2009 P1 for 10 minutes using the Takahashi TOA 150mm refractor and SBIG STL11000M camera. The moon was up at the time, but I was imaging away from the main area of moonglow (GRAS recommend imaging objects at least 60 degrees away from the moon) so I guessed everything would be OK – and it was !

Considering these images are just 10 minutes exposure I was pretty blown away by the results !! There’s a nice tail extension on the comet and the supernova is clearly visible in M101 as a 10.5 magnitude (now 9.9 September 6th ! ) exploding star which is now easily rivalling the galactic core in brightness. I’m used to processing Jpeg and Tiff files from the DSLR for astro images so the FITS files that you download from the GRAS server were a bit of a mystery to me. I downloaded the FITS liberator software and read the manual then got stuck in with the initial processing and saved the results as Tiff files. I was totally amazed at the quality of the images when I opened them up in photoshop for a bit more tweaking – nice clean images with hardly any signal noise. OK so i’m now officially hooked on remote telescope imaging 🙂

Anyway – here are tonights images greatly reduced in size (and quality) from the Tiff originals

M101 Pinwheel Galaxy and Supernova 2011fe which is marked by the arrow

Comet C/2009 P1 Garradd

GRAS – Global Rent A Scope – First Light

September 3, 2011 Leave a comment

It does feel like cheating at first. You should really be out there in the elements connecting everything up amidst a rats nest of wires and cables, balancing the equipment, aligning the mount, locating your objects to image, focussing, imaging, transferring the files, calibrating and processing – or at least you would be if there wasn’t wall to wall cloud, which is what I have had over the last two weeks. I’ve been going slightly crazy looking at all the great images of comet C/2009 P1 Garradd appearing in numerous photogenic pairings as it passes by famous deep sky objects. And then there’s Supernova 2011fe in M101 which has been slowly brightening to its maximum current magnitude of 10.5, rivalling the galactic core for brightness in images. While a few notable images have rolled in from staunch amateurs and their home observatories many people have been using remote telescopes to capture their own visual keepsake of these unique astronomical events.

You soon get over the guilt of going fully remote of course, particularly when you realise that this is how professional astronomers grab their images anyway, just with much bigger telescopes and more sophisticated imaging devices. And even the amateurs are not really roughing it these days. Most of the top imagers have fully automated observatories and merely have to set the imaging targets on a computer and the kit does the rest while they go back to sleep. So don’t feel guilty, just get those images taken any way you can and revel in the fact that full remote automation is even available to the amateur these days.

Many of the remote images I have seen originated from GRAS or Global Rent A Scope http://www.global-rent-a-scope.com/ which has an array of telescopes available in three locations including New Mexico (US), Spain and Australia. So I figured I would initially try the system out on the Free Test Drive offer using GRAS 003 in New Mexico which is a Takahashi TOA 150 refractor (1100mm/ f7.33) paired with an SBIG ST2000 XCM 2 megapixel one-shot color camera. The Test Drive deal gives you 60 points to use which basically gives you about an hour on this setup with the ability to capture 3-4 ten minute (600 second) exposure images. The registration was painless with just basic details collected, then you are sent an activation. After activation an email arrives by return with your unique username and password. You then wait 15-20  minutes for your account to go live on the GRAS servers. When your account goes live you sign in to the GRAS Info Centre where the first thing to do is check if the observatory you are using is in the night portion of the colour day/night animation. Also check if the all sky camera for the observatory shows a clear sky with obvious stars. I then clicked on the G3 telescope when the ‘Available’ message appeared in the constantly refreshing list of telescopes.

The GRAS Info. Center with me on the G3 telescope……

On the Free Test Drive your options are pretty limited once you get to the actual telescope control screen. You can only choose to image a set number of famous objects (all of them Messier objects when I was using the system) from a short list using the One Click Image system. They will all be objects at least 45 degrees above the horizon and if you choose something below that level you will get a message telling you the object is unavailable. To my dismay M101 was out of range at the time (11.20 pm US time) and comet C/2009 P1 wasn’t even listed, so I was left with a fairly mundane list of familiar Messiers.

As the camera is one-shot colour providing a fully RGB calibrated image I decided to target some colourful objects and picked the M27 and M57 planetary nebulas. The exposures are locked at 10 minutes (600 seconds) so you just click on the Submit button next to the image of the object you want to target and off the telescope goes. A scrolling script screen provides detailed feedback on the whole process and after about 12-15 minutes you get the message that the session is complete. The server then automatically calibrates and processes your image for you and sends it as a jpeg file attachment in an email.

The initial single jpeg images you will receive by email are poor quality heavily compressed jpegs weighing in at just 80kb in size and 800×600 pixels. These are just the preview images however and you should shortly receive the zipped FITS files by email or you can download them from the GRAS server using an appropriate FTP client (I use the GRAS recommended FTP Surfer which is free). For a 10 minute exposure the results are quite surprising ! After converting the calibrated FITS file to SBIG RGB in Maxim DL5 and stretching the levels I did a  bit of gentle noise reduction, increased the contrast in the nebula slightly and increased the star colour using Noel Carboni’s Astro Tools plugin in photoshop. There was M27 in glorious (and fairly accurate) colour with plenty of detail in its structure and a nicely dense starfield around it  – I was feeling quite chuffed 🙂  M57 was a bit lost in the widefield image and stared at me like some brightly coloured Saronesque eye, but even that image looked decent after a bit of tidying.

M27 – The Dumbbell Nebula – 10 minutes, one shot colour – processed image

M57 The Ring Nebula – 10 minutes, one shot colour

At this point cloud rolled in and the New Mexico observatories all closed their doors for a few hours. I headed back to GRAS at around 4am US time and most of the telescopes were back online. Wanting to try a different scope I went for the G20 which is a Takahashi FSQ-ED 106mm 530mm / f5 widefield refractor paired with an FLI ML8300-C  8.3 megapixel one-shot colour camera. At this point I should have done my research as I chose M76 The Little Dumbbell nebula to image. This is really too small an object and too distant for these widefield scopes and looks hopelessly lost in a very pretty starfield – lesson learned !

M76 Little Dumbbell Nebula – hugely cropped !

Having now set up Stellarium (version 0.11.0) for the various observatory locations I have researched the correct times to catch M101 and C/2009 P1 more than 45 edgrees above the horizon in New Mexico. I also put the various telescope and camera combinations into CCD Calc 1.5 so that I could see what the field of view for M101 would be (C/2009 P1 FOV confirmed from other peoples images) and GRAS 03 seems to be the telescope for the job.  OK , i’m all ready for another session on GRAS 03 around 3am tomorrow morning UK time, weather permitting in the US. I’ll post up the results tomorrow – wish me luck !

EDIT 4/9/11 – Quick update – it was cloudy all night at the New Mexico location and the domes remained closed – so no images taken !

Categories: Astrophotography

Spots Everywhere ! 1st September Sun

September 1, 2011 Leave a comment

There are at least eight sunspots and just as many active regions on the sun right now but overall the strength of the magnetic activity remains low with no significant flares.

 

Categories: Solar