Malpi12

Looking on the bright side - now that we have nothing to see the rain-gods will take time off and we will have an exceptional clear sky tonight
 

10 minutes ago, robin_astro said:

Even if it had existed it would have been too bright for any normal supernova at maximum at the distance of the suggested galaxy so would likely have been a transient object in our own galaxy (nova, dwarf nova, luminous blue variable etc etc) but since it does not exist that is hypothetical  The correct procedure for reporting transients is to make a follow up observation first and check for any other possible sources eg asteroids etc. Only then should a discovery claim be made either through TNS or via the IAU transient object page

http://www.cbat.eps.harvard.edu/unconf/tocp.html

The other thing that had me puzzled is that if it had been mistaken ID with the nearby star the magnitude difference was so large how could it have been such a mistake ! So I eeeked !!
 

10 minutes ago, robin_astro said:

it is a false alarm and does not exist

https://www.wis-tns.org/object/2023mlt

 

Thanks  @robin_astro,
I wondered if that might be the case ! as the "Type" on the Rochester page was "unconfirmed"
but the date was 6th, which was a long time to be still on the page with nothing in their updates page
  and tks for the def. link 
 

eeek aavso is telling me AT2023mlt "Star AT2023mlt does not exist in VSX"  what am I doing wrong I wonder ?

41 minutes ago, michael.h.f.wilkinson said:

AAVSO Variable Star Plotter       with DSS data:

Thanks for the alert @michael.h.f.wilkinson  -  and Ohh I didnt know DSS could be added, must have another look in the aavso destructions !. I always have trouble aligning aavso charts with stars in stellarium, this should make life a lot easier.

I shall have to go portable to catch this one as it is below my treeline all night from my home. 

19 minutes ago, Stu said:

Thanks Michael. What’s the mag of that star, for reference/comparison?

I'm not Michael but I am just setting up my Stellarium for this. it says m9.4 in my version, no moniker though, I'll look in CdC later for it

A brief look out about midnight local (BST) revealed (between drifting clouds) Corona Borealis was missing R Crb !
A hasty grab of the camera on a tripod gave me 5 usable frames, out of 20, to stack and a quick&dirty comparison with some nearby stars in Stellarium gave me :-
297 7.58 HIP77373
257 8.08 HIP77743
234 8.33 HIP78001
184         R Crb
157 9.43 HIP77479
the first column is pixelpeeking in Gimp from the DSS stack
so I guessed about mag9 for R Crb

1 hour ago, Stu said:

Not totally sure of your question but my image was taken with a 740mm focal length scope and an 18mm BGO (42 degree afov) giving a 1 degree field of view.

Thanks, yes, I was trying to work out what size of lens my crop image was equivalent to,

more here >

On 27/05/2023 at 20:52, Malpi12 said:

Imagine my surprise when I found a bit of M101 as well in there.

Later, after some practice on stacking loadsa subs in DSS and tweaking in Gimp,
1000 subs takes a long time on my ancient windows 7 machine !

I spy spiral arms, (just !!) , but with 5 times as many subs as in previous post, I had expected a better signal

1000 x 2sec, Canon 60D,  135mm f2.8 vintage lens,  ISO800, 100 bias, no darks, no flats.

Crop of 703x874pixels from original 5292 x 3465 subs  and exaggerates the star bloat
which I think makes this equivalent to a 1000mm lens ?
[ 5292/703 = ~ 7.5,  then 135x7.5= ~ 1000mm ]

Yes, ok

I was about to update my "discovery" post in beginners imaging forum with it with  more details, when I saw your topic. It is a severe crop (and stack) of 703x874 pixels from original subs of 5292 x 3465. If I have my maths right makes it a 135x7.5 = approx 1000mm equivalent lens ?

 Yes !
This is a gif of my 1000 x 2sec subs ( Canon 60D 135mm lens, crop, fixed tripod) experiment  under yours rotated and horizontal flip.

Thanks to @robin_astro  for the alert of SN 2023ixf in M101.
Normally sn in galaxies far far away are only of armchair interest for me, being too dim for my current limited equipment.
However this one at about mag.11 was worth a try with my Canon 60d +135mm vintage lens on a fixed tripod.

 200 x 2sec subs gave me this image below. not pretty but it is there ! The comparison star magnitudes are from an AAVSO chart. Imagine my surprise when I found a bit of M101 as well in there.

North Somerset.
Clear of clouds but high haze nelm 4, north horizon limited to 25deg

Nothing !
I was out at 00:15 to 00:45 during the first red alert
and again at 01:30 to 02:00 during the second red

Now it is an amber alert and there is an inviting bottle of amber nectar on the shelf over there, what should I do ?
 

21 hours ago, AstroKeith said:

The radiation is weaker and even more 'red shifted'.,

,is a super sensitive and high resolution version of COBE

Thanks, that is what I needed to jump start my brain !

I see now that is where I was going wrong with Webb. 
I  have been happy over the years to accept that the hot glow ( the CHG ! ) from the early universe has, by now, stretched and shifted all the way to a dim 2.7-ishK CMB,   -- I have failed to apply the same to "conventional" ancient, early, bright objects like stars, galaxies and Quasars etc., (and anything else that formed at or about 'First Light') which XhaveX will also become stretched and shifted into the darkness of the End Theories --   

The clue, I think,  was there for me if I had had the eyes to see it: the fact that Webb is working in the IR. (also being able to see through intervening dust)  ?

edited to change have into will. Cant seem to do strikethro when editing ???

Yes, thanks, got the bit about the space between, I prob. should not have said "cliff edge",
Similar - the CMB is not far away- the glow is still all round us but now very cold and weak.

I am thinking The Cold Dark End, or The Big Rip was part of this -observable- scenario ?

I am off out to a party in a min. so a few bottles may help to clarify
 

13 minutes ago, AstroKeith said:

Actually the c/3c cliff does not exist. The paper referenced by Andrew above, although dated now, does 'prove' that it's not a barrier. Its all about frames of reference.

The problem I believe with seeing yet further back, or continuing to see what we can just see now, is distance and red shift. The radiation is weaker and even more 'red shifted'. Actually 'red shifted' is now not quite right as we have shifted beyond red. What we will need is a super sensitive and high resolution version of COBE.

A useful way to think of the expansion, is not that things are moving through space to be further away, its that the space itself between us that is expanding.

Sorry, pressed send too soon

The bit about Webb that I am thinking now is :-

How close to the edge do things need to be to get lost in say 1month, 1 year, 1 million years.

I mean if Webb can see back to the first light approx 100,000 y after last scattering (300000ish y after BB) do we need to wait 100000y till we start missing things over the c (3c) cliff edge  ?
 

10 minutes ago, AstroKeith said:

You're right.

Except we're unlikely to be around then!

Thanks !  And yes I used "awhile" as homework for my chums

Would it confuse things even more if this simple soul said :-

Although the "observable" universe is getting bigger as time passes, there is going to be less  & less to observe, as more "things" will be expanded beyond c (or 3c ?)
Only the Local Group and the Milky Way will remain, gravitation-bound, for awhile. Until the increasing rate of expansion trumps even that.
So make the most of what Webb can still see.

But I could be wrong ? I have a feeling that I am missing something ! Cos that bit about Webb dont feel right

Virtual Telescope Project  

https://youtu.be/P0sD-qcnvpY

nice show ! Amazing, he is 100km from his scope and can do all that,,,,I have probs when it is 6" in front of me !

19 minutes ago, wimvb said:

It shouldn't be that dim. Maybe that site shows the absolute magnitude, which would be the magnitude if the asteroid were at a distance of 10 parsec (32 lightyears). I checked on the site, and it really doesn't say if it is. 

Good point ! So I dug deeper :-
http://astro.vanbuitenen.nl/neo/2023 BU
Rising from 26.8 "today 26Jan"  to 17.5 at "brightest 26Jan"  ???!
More quote -
Based on its absolute magnitude (Hₒ) of 29.4 and an albedo between 0.25 and 0.05, the estimated diameter of 2023 BU is 4 - 8 m.

Still out of my league!
 

Experment with a vintage Pentacon 50mm f1.8 lens,  5am Jan20th, -5degC brrr
Canon 60D, fixed tripod

 100 x 5s ISO800, stacked in DSS

 approx. 400pixel crop from the 5000pixel stacked original,
 lots of levels&curves in Gimp and some extra saturation.

Very surprised to find both green and pink in it's tail.
So yes, deffo have a go

[ I would have posted earlier but 3 days without internet reduces the will to live (thanks Openreach - not ) ]

I saw this one on the BBC website earlier today, remarkably close !
https://www.bbc.co.uk/news/science-environment-64411469

and looked it up on Van Buitenen  who lists it at mag 26.8
ah! just a bit dim for me, about 16 mags too dim !
http://astro.vanbuitenen.nl/neos

Good luck 

Was not sure if I should put smile or sad on these posts ! 

Bad news, @Jonk,  that is the whole Borg:Collective trying to put salt on your tail !

3 hours ago, Jonk said:

This is my favourite - cursing at the time, but in a way glad it happened cos I look back and laugh!

Was anyone able to make a mag estimate last night ? (cloudy here)

astro.vanbuitenen.nl is now showing some new visual obs from COBS in the 5.5 to 6 range!, and two ccd obs are a little up as well  (but not quite as dramatic !) from those being reported when I did my estimate.

Hi all, thamks for all the heads-ups, it got me moving !
 I had this one on my to-do list for later in the month when it would get above my obstcles. However, last night (17/18 Jan) about 12:30am I thought best check out my eastern view in preparation and took some  East and NE shots with a 28mm lens on my Canon 60D
I was surprised at seeing Bootes allready above my neighbour's garage, and when I later stacked the 25 8sec subs I found C/2022/ E3 (ZTF) lurking in the noise at the edge of frame !

It will not win any apod ! but, not to waste a serendipity I used it to check out its almost star-like magnitude against Stellarium mags.
Between 7.5 & 8.1 as others have already found  Just above it averted imagination shows a close 10mag star and I fancy there is a bit of extended coma to the left and above-left of it ??