Gfamily

3 hours ago, markse68 said:

the 4 I circled look bright (young/close?) and the dust doesn't look particularly dense there

I guess appearances are deceptive... 

Just now, gorann said:

I am really puzzled by all those additional stars in the JWST image, including many very bright ones. I did not know there were pure IR stars, but then what do I know.

They'll be stars that have had their visible light blocked by dust. 

2 hours ago, maw lod qan said:

I just read a report that says NASA is considering granting the SLS to one group with out any consideration of competing companies.

[...]

I wish I could link to the article, but I'm almost illiterate when it comes to a lot of this.

If not this one,  it'll be a similar one

https://spacenews.com/nasa-outlines-case-for-making-sole-source-sls-award-to-boeing-northrop-joint-venture/

On 09/10/2022 at 11:31, JimFR said:

.’ve changed laptops since 2016, and noticed when rebuilding that Registax is pretty ancient now, but AS! doesn’t do wavelets.

So, got to wondering what people are using these days?

My only real planetary image was captured using a modified £2 webcam using Sharpcap

After an initial process in Registax, an astro club colleague suggested I try processing in AS!3. Following the initial stack, I then dropped it into Registax and applied the same wavelets as before.

2 hours ago, Elp said:

This seems kind of unreal (WR140 dust shells):

https://www.bbc.co.uk/news/science-environment-63234027

 

What I find interesting, is not just the rings, but the additional rays towards top-right, bottom-left and also top-left. 

They look almost like diffraction spikes, so I'd be interested to know what happens if the 'known' SPF is subtracted.  

31 minutes ago, ED Splitter said:

Well the big easy ones coming to northern skies at reasonable times are Pleiades and Orion Nebula. Orion is spectacular but it’s so obvious. My personal favourites are the ring nebula and the double cluster. They are two incredible targets that really take your breath away. 

Good suggestions, above - though I would warn that the Double Cluster in a Mak is likely to be the Cluster and a Half 😀, as the field of view is relatively small.  As suggested, double stars can be good targets - Mizar and Alcor in Ursa Major is good, and Albireo in Cygnus is excellent.  You can also try for some Globular Clusters - M13 in Hercules is good as it's easy to locate ( 1/3 down the right hand side of the Keystone) and also easy to identify because of the two stars with which it makes a triangle. 

Dark skies will always help - particularly for larger, more diffuse objects  and I'd suggest getting a nice low power eyepiece as it should help with the contrast for these things. 

In case anyone is interested in why a head on collision seems to have made Dimorphos orbit Didymos quicker (rather than slowing it down).

According to a tweet from someone following the press conference, the orbital period has changed from 11h55m to 11h23m - which is 'apparently' about a 3x greater change than expected. 

So - worth doing. 

Well, it was pretty much clouded out here, and the Moon wouldn't have helped. 

Another look at the lunar calendar app advises that there will be a waxing gibbous moon on 5th November (as well as lots of fireworks and smoke here in UK), so maybe a better day will be towards the end of November, on 22/23rd - there be a minimum just after midnight on 23rd, and a New Moon later on the same day.  

Oh no, how disappointing.

I don't know whether there are any UK companies that can offer a replacement service.  A quick google suggests that Grover Optics offer a replacement for the Celestron 8" SCT, and as the UK agent for Celestron, they may be able to help with yours. 

The eclipsing variable star Algol takes about 9 hours to complete the eclipse process from initial brightness, through the dip, and recovery to full brightness. 

WIth a period that's about 3hours and 20 minutes less than 3 days, it can be tricky to get a timing when both the max and minimum brightness can be seen on the same evening - at least without having to wait up until the early hours. 

However, this evening (10th to 11th October), there will be a minimum at 1am BST, so it may be possible to have a look at about 8pm, and then have another look at midnight. 

The magnitude should drop from 2.1 earlier in the evening to 3.4 by 1 am. 

To compare the brightness - the Sky at Night website suggests Gamma Andromedae (2.1) and Epsilon Persei (2.9) as both are relatively close-by. Alternatively, the two stars at each end of the W of Cassiopeia are similar magnitudes to the Max and Min (Caph at 2.2, and Segin at 3.3 respectively) .  https://skyandtelescope.org/observing/the-minima-of-algol/

Unfortunately, the nearby not-long-past Full Moon won't help. 

If tonight isn't good, another good chance might be on 5th November, when minimum will be at about 7:20pm, and full brightness should be restored by midnight. 

You can DIY one using an A5 sheet of Baader film. 

I cut strips of card to fit around the OTA, and use double sided tape to hold the Baader film in place.

Cut a circle of film about 2cm larger than your aperture, and cut 'petals' for the outer 1cm all round.  

First strip of card snugly around the OTA

Put a strip of double sided tape right around the card. 

Put the Baader film across the aperture and push down the petals so they stick to the card. The Baader film shouldn't be pulled too taut - it's not meant to be like a drum. 

Then another strip of double sided tape, and then the second strip of card. 

The whole filter assembly should then fit snugly and securely over the objective. 

If you have a finder scope, remove it, or make a similar filter for the finder's objective as well. 

It is possible that the need to re-focus is exacerbated for astronomical observations because the iris is wider at when you are making nighttime observations compared to your iris size when birding during the day. 

Have you tried using the Travelscope at night, to see if the 'no need to refocus'  applies there as well? 

It is also possible that for some reason when you use the Travelscope for birding, you are automatically putting the final image at a virtual position that is within the accommodation distance for your uncorrected vision. 

3 hours ago, Marvin Jenkins said:

Running shot gun visible light to JWST let’s hope something can be done. 
Far too valuable an asset to just let go to the atmosphere.

Marv

It seems the real 'irreplaceable' aspect is the ability to image in the UV - HST's performance in optical wavelengths can be pretty well matched using ground based adaptive optics, but its UV capability is not going to be matched until the deployment of the LUVOIR major space telescope in 2039. 

It would be interesting to see whether a combined power - stabilisation unit could be clamped to the HST to replace the functionality of the failing/failed inertial wheels. 

An interesting question is whether the torque dumping capability (in part currently done by interaction with the Earth's magnetic field) would continue to be effective if it was boosted to a significantly higher altitude.  Well, I have no doubt that it could be replicated, but it is an additional factor to contribute to the complexity 

3 hours ago, 900SL said:

I found a great article which considered this in depth.. the summary being that because dark matter doesn't interact apart from on a gravitational basis, it doesn't tend to collapse down like normal matter does. Instead it remains dispersed in a halo and  its angular velocity is pretty much preserved. 

So no dark matter stars or holes..

However, any dark matter particles that are on a trajectory that passes through the cross section of the Black Hole will be absorbed into it, so the mass of the BH will increase over time, should there be a steady stream of DM impacting on it. 

There is a suggestion that although DM particles don't interact with Standard Model matter, they may interact with each other - and this modifies the distribution of DM particles around galaxies (the observed distribution doesn't seem to follow what would be expected if there was NO self interaction, so it proposed that there is SOME interaction, albeit not one one that is understood).

I use a diagonal, so it's always seen with the two eyes at the bottom - it's clearly a dragonfly.

Two huge eyes, four wings . A dragonfly. 

Although for Saturn, I think a telescope would be better, I wouldn't rule out getting binoculars, there is so much that is really accessible with a simple pair of 10x50s or 8x40s, and these can give you a lifetime of great observing. 

A member here ( @BinocularSky ) writes a monthly newsletter specifically for binocular observers, and that will give you enough to enjoy each month.  It can be found at www.binocularsky.com. 

With binoculars there are lovely asterisms, open clusters and nebulae to look out for - and they are ideal for observing the moons of Jupiter and the changing face of the Moon from night to night. It's just that their magnification is limited, and Saturn is one of the targets that are just too small to be really impressive.  

@Binocularsky writes regularly for magazines about what to look for in the night sky with binoculars, as well as binocular reviews. He knows his stuff.  

I reckon you need at least 25x magnification to see the rings of Saturn at all, and binoculars that powerful are a handful, so best tripod mounted. Personally though, I would say that you would be far better off getting a small telescope plus a suitable eyepiece that will give you 30 or 40x magnification at least. Depending on the aperture, you can then look to increase the usable magnification (work on the basis of aperture in mm = typical max magnification - you may do better, but it'll be very dependent on the atmospherics)

I have seen the rings using a not very good spotting scope, so that might be an option if you want something that would have daytime/terrestrial use as well.   

There is also the Our Galaxy view, which is available in a browser, as an app or as a download for laptops

Available here https://www.otherwise.com/download/

4 hours ago, Gfamily said:

Based in UK, so UTC+1.

Away from my pc at the moment, don't think it's to do with time zones 

Now back at PC - Stellarium correctly showing time as UTC+01:00

• Next minimum according to S&T calculator webpage 09:34 UT on 02.10.2022
• Next minimum according to Stellarium 0.22.2  - 2022-10-02 05:46:55 UTC

5 hours ago, alexwolf said:

No, but the start date and period may be different. Sorry, I didn't check the latest data from GCVS for Algol.

P.S. Stop! @Gfamily what about your time zone?

Based in UK, so UTC+1.

Away from my pc at the moment, don't think it's to do with time zones 

This is from the Autumn Astrocamp 2022 in South Wales last weekend. 

SW 127 Mak on an AZ GTi mount, being operated by my phone, and a Sony A5000 operated by an intervalometer. 

And result... 

1 hour ago, bruno said:

thanks Peter, where will i find that?

I think he might mean vibrance rather than vivacity - it's under the Adjustments tab 

1 minute ago, nitram100 said:

Awesome thanks everyone, will keep an eye out on the astrobuysell site 👍👍

One question, can dslrs take decent planetary and lunar ?

Cheers

Lunar - definitely

Planetary - hmmm. The problem is the small image size on the sensor. If you use a barlow, and you have a long focal length, it can help, but as the image is straight onto the sensor, it will be small 

A usual approach for planetary is to capture a video stream for several 10s of seconds, and these are then processed using software. Some cameras will compress the image, so results may not be optimum. 

Do consider mirrorless cameras alongside dSLRs. 

I have a Sony A5000 (which isn't ideal, the A6000 is meant to be better); it has some issues, but it's 1/3 the weight of the dSLR that I was using previously.   That and a wired intervalometer makes it relatively easy to get into imaging.