. Venus, Uranus and Mars (1 Viewer)

[Binastro]

. Not birdwatching but a test of binoculars.

About 15 minutes ago in a clear but very light sky, looking at the planet Venus in the South West there is a tiny star just below Venus, perhaps 0.2° away.
This may be the planet Uranus.

4.1° to the lower right of Venus is the planet Mars.

I used the Canon 18×50 binocular and it was quite difficult because of the odd angle.
I'm not sure whether it would be visible easily in non-stabilised binoculars.

P.S.
I just tried with 8.5×44 binocular and it was impossible to see the tiny star. I think this would be very difficult without stabilisation.
I'm trying to find out the separation, it might be about 0.4° or so.
The planet Uranus is listed as 0.1° south of Venus tomorrow March 4 at 20:00 hours UTC, but in England I think that about 1825 UTC may be the easiest. You will need a clear sky.

In the USA this evening Venus and Uranus should be a good challenge for binoculars.

P.P.S.
I must apologise profusely, I think.
I definitely saw a faint star just below the planet Venus, but my friend checked using Starmap, I think, and there are two stars about the brightness of the planet Uranus and Uranus itself, but they are all presently about 1° from Venus. I don't think that I would have seen a star much fainter than this.

So what I saw I think must be a faint ghost image of Venus, which is presently only 12 arc seconds across. This would have been because I was viewing through double glazing. It may be that because Venus is very small at the moment it's faint image through maybe two reflections is very small and point like.
My friend suggested that I looked through the double glazing at a bright star, but there is nothing as bright as the planet Venus to check and anyway Venus is probably, setting at the moment.

So the moral of this story is that if you try tomorrow to see the planet Uranus 0.1° south of Venus you should do it outside not through double glazing.
This is a good opportunity to see the planet Uranus, which you may well have never seen before. It is a good binocular challenge.

Many years ago, I thought I discovered a new comet, but it was in fact a ghost image of the planet Jupiter a long way away from the field of view of my binocular.

Although I am an experienced observer, it seems that I can still be caught out.

However, tomorrow at about 1825 or 1830 UTC in England the planet Uranus will be 0.1° away from Venus, so this should be a good challenge for binoculars.

Venus is about 5000 times brighter than the planet Uranus, which is why I thought I had actually seen it this evening, as the tiny point source object was the right brightness.

In the USA this evening the planet Uranus might be about 0.7° above and to the left of Venus but I'm not sure of the actual separation or position.

But the trio of Venus, Uranus and Mars in the same field of view in a binocular is unusual. The colour difference between Venus and Mars is also striking.

 

[Binastro]

. Regarding my last post above.
It may be that with Uranus only 0.1° below Venus at the 7 o'clock position tomorrow, it may be too difficult for most binoculars.
The problem is that the window for observing this event is small.
The sky has to be very clear, but the sky is still light, and if you wait till it is fully dark Venus and the planet Uranus may be too low for the observation with binoculars.
The observing window maybe only a half an hour or one hour at best.

If you have a spotting scope, that would be a better bet to find the planet Uranus.
Afterwards, if you have a large binocular such as a Zeiss 15×60 it may have a large enough field to just show the three planets at the same time.

I just hope that tomorrow evening here it is is clear as it was this evening so I can have another go.

The event should be easier in the USA this evening as the separation of Venus and the planet Uranus is greater.

Venus is actually about 8000 times brighter than the planet Uranus at the moment.

P. S.

A friend has given me details for New York at 1800 local time this evening or 2300 UTC.

Venus is 26° high in the West with the planet Uranus at the 11 o'clock position just under 1° away.
However, the Sun is only 2° below the horizon at that time.

So I think one should observe from 1830 to 1845 local time and maybe up to 1900 local time.
If the planet Uranus is not found with binoculars it would be probably fairly easy with a good spotting scope on a tripod, assuming the sky is clear and transparent.

 

[Red_Shoulder]

Thanks for the info, maybe it will clear here and I can take a look. Here's a link from Astronomy with some good info

http://www.astronomy.com/observing/sky-this-week/2015/02/february-27march-8-2015

 

[Boro Birder]

Thanks for that, space interest me a lot, since I was a kid sat half way up Mount Snowdon and seen a clear sky, got some wonderful views of Jupiter in early winter, see the 3'of the 163 moons excellent, however I was using a 80mm Scope with a 60x magnification.

Damian

 

[typo]

Thanks for the info.

I did have a quick look last night round about 8 o'clock, but though I could see Mars, Venus was no where to be seen at that time. We've had several clear evenings in the last couple of weeks and it's usually been shortly after six when I've closed the curtains on my west facing windows and I've been noting the two of them drifting apart. I'm not a star gazer and I think it's the first time I've spotted Mars without being told where to look but when the two of them were side by side there was no mistaking it. I'll try to remember to have a look with binoculars/spotting scope this evening.

BB, Not something I've done very often but you should be able to pick up the sparkle of Jupiter's moons with a hand held 8x and count them easily on a tripod on a good night. I did have a look with my neighbour's 15x110 once and that was pretty impressive, though I did mistake an in-line star for an extra moon (as Binastro was kind enough to point out. )

David

 

[Binastro]

. Thanks David,
I felt a bit foolish last night, but I was under pressure because the observation was time sensitive. There is a critical period when the three planets are high enough and the sky is getting dark enough to see them.
Also I did not know exactly where the planet Uranus was last evening.

This evening, I think that the separation of the three planets is such that even a Zeiss 15×60 doesn't have a wide enough field.
One would need I think a good 12×56 or possibly 12×50 binocular with a field of 5.5° to have a chance of seeing all three in the same binocular field.
This should be possible from the USA, but in Britain the separation of about six arc minutes means that it may not be possible to see the planet Uranus when Venus is 8000 times brighter. But it sure is a good test for the best binocular.
Perhaps the best binocular for the job might be the Canon 10×42L IS with the stabilisation on. You will need a really transparent sky.

As to photography, I am informed that two exposures will be needed for Venus and Uranus as Venus would be overexposed if you try to get them both on the same exposure. And the overexposed image of Venus would probably overlap the planet Uranus and swamp it.

A good large spotting scope at 60 times I think should show Venus and the planet Uranus, certainly from the USA and hopefully from Britain.

David, if you can persuade your neighbour to get out the 15×110 binocular that is actually probably the best binocular for the job, as I think it had a ridiculously large field of view as well as the aperture and magnification to see all three planets this evening in the same field of view, although the clouds at the moment are not promising.

 

[Binastro]

. Following on from the last post.
At least somebody had better luck then I did last evening. At 1815 UTC he saw Venus, Mars, Jupiter and the Moon with unaided eyes and the planet Uranus was easy in a 15×50 binocular. I'm not sure if he saw Venus, Mars and Uranus in the same field, probably not.

David, if you have access to the 15×110 binocular this evening and the sky is clear, it would pay if you started observing early while the sky is still light. With such a large aperture, the three planets would be higher and Venus would not drown out the planet Uranus.

 

[SteveTS]

The sun is on it's way down now but there is an annoying amount of low cloud spreading from the west here.

Venus was very bright last night ; with a hand-held 6.5x binocular there was a good view of Mars and the heavens but no finer detail. I'd be struggling with any higher magnification unsupported !

Shouldn't be hard to see the Moon unaided ... it will be full tomorrow, and a great subject for testing any new pair of binoculars.

 

[typo]

If Uranus is 8 o'clock to Venus and very close in then I think I've got it. The sky wasn't as clear as previous evenings and it wasn't 'till about 6:20 that I could see Mars unaided. I wasn't sure where I should be looking but I spotted the feint dot at about 6:30 with my 20x50 and in the next ten minutes I could see it with my 12x50, then 10x42 and with a bit of patience my 8x42. That was fun, thanks Binastro.

David

 

[Binastro]

. Very well done, David.

Unfortunately, for me there was a large bank of cloud until 1930 UTC approximately, when Venus was far too low in the haze.
I'm particularly pleased that you saw it with your various binoculars and even with the 8×42.
Was the 20×50 a spotting scope or a binocular?

I have another positive sighting from somebody using a 60 mm average quality spotting scope. He says it was between the 8 o'clock and 9 o'clock position, maybe a little later than you.

Thanks again David for completing my uncompleted task.

 

[typo]

The 20x50 is a spotting scope. It's the better one of two I bought in an auction I bought for £30. :t:

David

 

[typo]

Conditions seems rather trickier tonight and I'm not at all sure I've found Uranus this time. There is a candidate, still at 8 o'clock but much further away from Venus this time, but I'm not convinced. Anyone else found it?

David

 

[Binastro]

. Hi David,
Uranus the day before you saw it was about 1° from Venus at the 11 o'clock position.
I think that at closest approach 20:00 hours on the day you saw it it was about 5.4 arc minutes from Venus at the 7 o'clock position.
So I think that it is moving relative to Venus about 1° a day, so now it will be quite far away.

What you saw this evening was probably a star of similar brightness.

The day before you saw it there was the planet Uranus and two similar brightness stars all about 1° from Venus.

The planet Uranus is interesting because it was discovered by William Herschel in 1781 March from his house in Bath with his home-made 7 inch reflector telescope.
It had been seen previously fairly often but not recognised for what it was.
William Herschel thought that it was a new comet for two years, but eventually everyone recognised that it was a new giant planet.

It had been identified as early as 128 BC and listed as a star.
It is quite easy to see without optical aid from a dark location.

William Herschel discovered it because it showed a sizeable disc, and even my old 3 inch refractor showed it as a disc. I think it looked blue, I cannot remember after all these years.

Your observation was excellent, with very good binoculars and very good eyes and also skill.

However, your observation does illustrate the difference between a discovery observation and observing something that you know is there, and then observing it as a test object.

To discover Uranus, as seen by you 0.1° from Venus, would probably need a good 4 inch refractor or a good 5 inch reflector. And it would be a surprise to the Observer.

You managed to pick it up in a 20×50 spotting scope, which rather surprised me. After all the planet Uranus is presently 8000 times fainter than Venus, and I thought that Venus might look bloated because of its brilliance and actually it's disc might be so expanded as to engulf the planet Uranus.

The other report I had was from somebody using a 60 mm spotting scope at 54 times, because the lower magnifications were giving ghosting, which is not something you want for this type of observation.

Was the 20×50 spotting scope mounted on a tripod?

Anyway, you then went on to see it in 12×50, 10×42 and finally in an 8×42 binocular.
Had you asked me beforehand whether this event could be seen in such a small instrument, I would have probably had said 'no' or that 'I don't think so'.

I think that your eyes are better than mine, which are not so good nowadays.

I can ask my friends who have something called SkyMapPro I think, which has amazing capabilities regarding positions of astronomical objects down to to very faint stars. For the computer literate it is I think an excellent program, but it costs quite a bit?

They are free programs that you can use also, and I think that you will find that the separation between Venus and Uranus is may be a few degrees now.

I don't suppose that you were able to see the planets Mars, Venus and Uranus in the same field. Maybe you did.

 

[Binastro]

. Regarding my last post.
I think that the free program that I had on an old computer was called Stellarium.
I don't have this at the moment, but there is I think an updated version for free download.
Not being computer literate, I don't want to mess up my computer, but others should find it okay I think.

 

[typo]

Binastro,

Thanks for the additional info.

You seem unsure that I found Uranus the other day. You might be right.

In some ways the observation with the 20x50 (on a tripod) was the trickiest as the glare from Venus was so bright but eventually there was an adjacent feint speck that wouldn't go away as I placed Venus at different points in the FOV. It was very small but seemed a disc not a point and didn't 'twinkle' so I was convinced at the time. The view was much cleaner when I knew where it was with the 12x50 and 10x42 as the glare was less intrusive but the candidate was no more than a point at those magnifications. I needed an extra couple of minutes for my eyes to further adapt to the view with the 8x42 but it was definitely there. I checked again around 20 minutes later and it seemed a little closer.

I'd quite happily accept that I didn't see it this evening. Mars was barely detectable with the naked eye so I'm not sure a sighting was possible at all. I just couldn't find a better candidate.

I didn't try to put the three in the same FOV but I suspect even my 7.2* 8x42 might not have been enough.

David

 

[Binastro]

David, I didn't mean that at all.

I'm pretty sure that you did see Uranus and with each instrument.
. It is just that I had no idea what to expect beforehand not having seen it myself.

. But the other observer, who has seen Uranus more than 1000 times found it to be easy in the 60 mm spotting scope. It was one 10th of the field separation, i.e. the distance between Venus and Uranus. So I'm pretty sure that you saw it, as long as you think that Venus was not so enlarged as to be 0.2° across, say 12 arc minutes across.
It is probable that at the time you saw the two planets they might have been about eight arc minutes apart, narrowing to about 5.4 arc minutes at 20:00 hours. But by this time Venus and Uranus were probably setting or near to the horizon for your location. Perhaps in Ireland they would still been seen well at 20:00 hours, maybe in the west of the country.

. Do you think that Venus was so large as to look, say, a fifth of the degree across?

The fact that you thought it was nearer 20 minutes in time later seems to also imply that you saw Uranus.

Also if the separation changed by 1° or 60 arc minutes in 24 hours then the two planets were closing at about 2.5 arc minutes an hour although at a somewhat glancing angle. So 1.5 hours before 20:00 hours they may have been in a position about four arc minutes difference. And even in 20 minutes the position might have changed about one arc minute.

I have no problem, David, with your observation in the way you described it. So long as you think that Venus did not appear to be, say, 0.2° across, then your description seems to fit correctly.

Uranus is about 3.5 arc seconds across, so at 20 times it would appear to be 70 arc seconds across. I'm not sure whether you would see this as being slightly not starlike.
I think that when I used to observe Uranus with a 3 inch refractor, I was probably using a magnification of about 80 times or 100 times, when the disc was very obvious.
As to twinkling, most planets, such as Mars twinkle when they are less than 10 arc seconds across. When they are 15 arc seconds or more they usually look steady, at least in England. But this is with the unaided eyes. So I'm not sure how Uranus would behave in the 20×50 spotting scope.

The fact that you were not sure whether you saw Uranus this evening is not at all relevant, as you had no idea that Uranus was moving so fast in relation to Venus. In fact it must be Venus that is actually moving the most.

 

[typo]

Binastro,

Without specifically checking I can't be sure but from memory I'd say Venus was something like 1/25th to 1/30th the FOV of the scope. Unfortunately I have no idea what the FOV is, I've not checked. The AFOV is nothing special so it's probably 2.5* at most. So that might 150 minutes/25 or 6 minutes or a bit less. I'll see if I can come up with some firmer estimates tomorrow.

David

 

[Binastro]

. Hi David,
I thought that the Kowa 20×50 was 2.6°, but looking at the Orion's Belt stars, which from memory are 2.736° apart, the field is 2.8°.
It may well be that your scope's field is around 2.5°. I suppose if you looked at Venus in a similarly bright sky as when you made your observation you could estimate the apparent diameter.
But if it's about six arc minutes then from the centre to the edge of Venus is three arc minutes, so if Uranus was 6 to 8 arc minutes from the real Venus then you could see Uranus as a tiny point separated from the edge of Venus's expanded disc.

In actuality, Venus is only 12 arc seconds diameter, but in a low-power instrument the glare makes it seem to be much bigger.

But it seems that your observations were correct and real based on Venus appearing to be six arc minutes across.

 

[typo]

I should have mentioned that while the separation with the 20x50 appeared maybe a little less than the width of Venus, it increased to several widths with the lower powers. I think that's what you were getting at?

David

 

[Binastro]

. Hi David,
I wasn't sure how large the apparent size of Venus would be in any of your scopes or binoculars. I was mainly concerned that Venus was not so large as to completely engulf Uranus.

I think that what you're saying is that Venus was apparently smaller as measured in arc minutes in the binoculars compared to the scope.

I did some rough calculations and in early March and also at the moment, Venus was and is moving 73 arc minutes a day to the left and up. Uranus was and is moving 3.0 arc minutes a day in roughly the same direction. So they are moving relatively to each other at 70 arc minutes a day or 2.9 arc minutes an hour.
In 20 minutes of time they were moving relative to each other 1.0 arcminutes.
Venus was rapidly overtaking Uranus.

By the evening of March 6 Uranus was I think about 2.3° lower right of Venus . Although it seems that Uranus is moving rapidly, it is actually Venus that is moving in the opposite direction.
So on March 6 if you were looking at Venus in the spotting scope Uranus was outside the field of view.
In the binoculars, with the 12×50 Uranus might have been near the lower right edge and in the other 2 binoculars it would be within the field of view, but maybe not noticed, especially if the sky was not transparent.

Today, March 7, Uranus might be about 3.5° to the lower right of Venus.
I'm not sure of these calculations, Stellarium would probably tell you better exactly where the two planets are.

It is likely that in the spotting scope and also in the binoculars, there will be several stars of similar brightness to Uranus. The only real way to know is if you have a perhaps large spotting scope at a high magnification that will actually show the disc of Uranus.

It would still be interesting to know, if it is clear this evening or another evening in similar sky brightness, what the apparent size of the expanded disc of Venus is in the four instruments you were using.

I've never actually estimated the size of Venus as seen in various instruments. When using an astronomical telescope, the magnification is sufficient to actually show Venus's disc, whose surface brightness reduces as you increase the magnification.