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Why does Mars look like a star?


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Hello everyone! I hope you are all doing well! I recently joined this forum for the express purpose of answering this question: Why does Mars look like a simple star through my telescope? I have a Starsense Explorer LT 80AZ refractor with a 10mm, 25mm and 2x Barlow lens, and my telescope has a max magnification of 189x! So why is it, on a pretty clear winters night, that the mighty Mars, the Red Planet , looks like a humble star. I love stars (who the hell doesn't) but i rather hoped to see a planet. What am i doing wrong? AM i doing something wrong or is my telescope inadequate (i doubt it though). I use the 10mm plus the Barlow, and still nothing. Is this just how Mars looks through a telescope like mine? Or maybe i'm not looking at Mars at all. Although, according to my research, the Red Planet currently resides in the constellation of Aries. Correct? Please. please answer my question as it is driving me up the wall. Plus, if anyone has the time, could someone recommend a good astronomy app, other than the starsense one, that you can just point at the sky? Thank you so much for reading this. Have a lovely day.

Edited by Goldenmole
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  • Goldenmole changed the title to Why does Mars look like a star?

I think there is a good chance that you are in fact not looking at Mars. Even though you may not be able to see many features of the surface with your telescope you should at least be seeing it as a disk. Not a point (a star) as you describe.

I use the free app, Star Tracker to find my way around the night sky. Especially when there's a planet to be found.

It's on google play. 

 

startracker.jpg.d1aff16e74f689ef797f39bceea67965.jpg

 

 

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I would double check your targets with a skyapp I use Skyview or Stellarium Mobile (Skyview is easier to use) to be sure but it could also be an expectation thing potentially? This thread is a fairly good primer :) 

 

My experience is with a similar aperture telescope (90mm) and to my telescope even with a barlow and my highest magnification eye piece Mars shows as a small disc with a hint of orange colour and sometimes a hint of shadowing on the surface if the viewing is very clear (something similar to the image I have attached but less orange and a little smaller). 

Be aware large magnification doesn't necessarily mean you will see more especially with objects that are very distant, I probably would be pushing my scope quite heavily at the below magnification and would likely be experiencing some focus / tracking shake as well.

image.png.77a651d48c2f4df2642f9fad260ef1ae.png 

Edited by wibblefish
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Hi @Goldenmole and welcome to SGL. :hello2: 

Every few years when Mars is at opposition, (i.e. Sun, Earth, planet in a line), it will appear a little bigger and you should appear as an orange/red/rust coloured disc. Also, depending on how close Mars is to Earth, you should be able to see the polar ice caps and maybe some surface detail. Last year [2020] was one of them. Bear in mind that Mars is about two-thirds the size of Earth. Planets will always appear as discs, except for Mercury & Venus as they are nearest the Sun. Stars will always appear as points of light.

I have a 70mm refractor and I have managed to see a Martian ice cap during August 2003 when it was 34.6 million miles away. That was the closest it was in my lifetime. The table below is via https://cseligman.com/text/planets/marsoppositions.htm

Oppositions of Mars, 1995 - 2037
 
Date of
Opposition
Date of
Closest Encounter
Closest Distance
(AUs / Millions of Miles)
Feb 12 1995
Mar 17 1997
Apr 24 1999
Jun 13 2001
Aug 28 2003
Nov 07 2005

Dec 24 2007
Jan 29 2010
Mar 03 2012
Apr 08 2014
May 22 2016
Jul 27 2018
Oct 13 2020

Dec 08 2022
Jan 16 2025
Feb 19 2027
Mar 25 2029
May 04 2031
Jun 27 2033
Sep 15 2035
Nov 19 2037
Feb 11 1995
Mar 20 1997
May 01 1999
Jun 21 2001
Aug 27 2003
Oct 30 2005

Dec 18 2007
Jan 27 2010
Mar 05 2012
Apr 14 2014
May 30 2016
Jul 31 2018
Oct 06 2020

Dec 01 2022
Jan 12 2025
Feb 20 2027
Mar 29 2029
May 12 2031
Jul 05 2033
Sep 11 2035
Nov 11 2037
0.67569 / 62.8
0.65938 / 61.3
0.57846 / 53.8
0.45017 / 41.8
0.37272 / 34.6
0.46406 / 43.1

0.58935 / 54.8
0.66398 / 61.7
0.67368 / 62.6
0.61756 / 57.4
0.50321 / 46.8
0.38496 / 35.8
0.41492 / 38.6

0.54447 / 50.6
0.64228 / 59.7
0.67792 / 63.0
0.64722 / 60.2
0.55336 / 51.4
0.42302 / 39.3
0.38041 / 35.4
0.49358 / 45.9
Edited by Philip R
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I second the Skyview or Stellarium on your phone, makes finding targets a bit easy for beginners (like myself). As others said, Mars looks like a bright orange disk (in my 8" Dob). I could see some dark patches on it the other night when the atmosphere seemed a bit stable. Menkar is near by which has an orange colour to it and that would show as a sharp point of orange light. A few dimer orange stars are also close by. Worth trying to find Pleiades first and then move down to find Mars if you are unsure.

A red dot finder, Rigel or Telrad will also help you point the telescope in the right area. There a few discussions on this forum on how to align them.

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On 08/02/2021 at 08:24, Goldenmole said:

Hello everyone! I hope you are all doing well! I recently joined this forum for the express purpose of answering this question: Why does Mars look like a simple star through my telescope? I have a Starsense Explorer LT 80AZ refractor with a 10mm, 25mm and 2x Barlow lens, and my telescope has a max magnification of 189x! So why is it, on a pretty clear winters night, that the mighty Mars, the Red Planet , looks like a humble star. I love stars (who the hell doesn't) but i rather hoped to see a planet. What am i doing wrong? AM i doing something wrong or is my telescope inadequate (i doubt it though). I use the 10mm plus the Barlow, and still nothing. Is this just how Mars looks through a telescope like mine? Or maybe i'm not looking at Mars at all. Although, according to my research, the Red Planet currently resides in the constellation of Aries. Correct? Please. please answer my question as it is driving me up the wall. Plus, if anyone has the time, could someone recommend a good astronomy app, other than the starsense one, that you can just point at the sky? Thank you so much for reading this. Have a lovely day.

Hi, I have the identical telescope to you and am 100% sure I'm viewing Mars through it and seeing exactly the same as you.

My conclusion, the optics are trash. I've ordered a new zoom lens, for simplicity, and a new diagonal. My issue with the diagonal is that I can see some sort manufacturing moulding through it and I can see 3 lumps which I assume are screws when I tinker with the focuser.

I believe the scope itself is of reasonable quality but the eyepieces, Barlow lens and diagonal are little more than plastic toys and will be replacing the lot.

I've seen Mars as a rust coloured star through the scope and used all kind of aids to pinpoint it and still, as soon as I try to magnify and focus in I just lose it and can see a black bar down the middle of the eyepiece. It's definitely a manufacturing flaw that I believe is in the diagonal. Replace it immediately and I'd consider replacing all of the eyepieces and Barlow at some point too.

The thing was built to a price point and they bundled ultra budget accessories to accommodate the Starsense kit

Edited by BaldyMan
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On 08/02/2021 at 13:14, Kon said:

I second the Skyview or Stellarium on your phone, makes finding targets a bit easy for beginners (like myself). As others said, Mars looks like a bright orange disk (in my 8" Dob). I could see some dark patches on it the other night when the atmosphere seemed a bit stable. Menkar is near by which has an orange colour to it and that would show as a sharp point of orange light. A few dimer orange stars are also close by. Worth trying to find Pleiades first and then move down to find Mars if you are unsure.

A red dot finder, Rigel or Telrad will also help you point the telescope in the right area. There a few discussions on this forum on how to align them.

I have the identical scope with the identical issue. I have used and not used the Starsense app. I can pinpoint Mars in the sky and have the same problem. The eyepieces and accessories are utter trash.

If you are using the 25mm eyepiece alone you can spot Plaedies and a few other open clusters quite easily, even punching through cloud to enjoy some clusters. But trying to magnify on to a planet or even use the 10mm and/or Barlow lens is an utter waste of time.

I have very mixed feelings about the scope. The app is great, when it works. You need very clear, dark sky for it to plate solve or you need to move slowly and star hop to help it out. You can't just view Orion and swing round for Polaris, it will just lose it's baring unless under very good sky.

The tripod is very lightweight and shakes in very mild gusts, it's also just too small and I believe designed for children. I have to kneel for everything I view through it. The only thing I can view standing is Sirius atm.

Eyepieces aren't plossl, not sure what they are but they're not fantastic. Will be saving the 25mm to use for attaching to a mobile phone mount. Everything else will get binned.

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19 minutes ago, BaldyMan said:

But trying to magnify on to a planet or even use the 10mm and/or Barlow lens is an utter waste of time.

I cannot comment on your telescope, but my 25mm EP is fine like you said. My 10mm is also rubbish. I have got a 8mm and 15mm BST (if you are on budget) and they are performing excellent on planets and DSOs. It is probably better take your time, and feel free to ask questions here. Everybody is super helpful , try include a budget for any upgrades, you can do it 'cheaply' with some advise.

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7 hours ago, Kon said:

I cannot comment on your telescope, but my 25mm EP is fine like you said. My 10mm is also rubbish. I have got a 8mm and 15mm BST (if you are on budget) and they are performing excellent on planets and DSOs. It is probably better take your time, and feel free to ask questions here. Everybody is super helpful , try include a budget for any upgrades, you can do it 'cheaply' with some advise.

I bought it in the knowledge that I would likely need to upgrade the eye pieces pretty quickly. I'll be keeping the 25mm to attach to one of those mobile phone camera mounts. Having read and watched reviews of this particular telescope I do believe it is simply down to the manufacturing process and the cheap components bundled in whilst the actual scope and starsense kit is of reasonable quality.

I have arriving soon a SVBony zoom eyepiece. I had looked at the OVL, Celestron and Sky Watcher Zoom eyepieces but stock is very low everywhere so I took the plunge with a cheaper model.

Another thing I have noted is that the tripod is very short, I'm always having to kneel to view anything and that's not ideal on cold ground. I will be keep this scope to give to the children as it is light enough for them to handle and operate on their own. I'll be investing in an 8" dobsonian like the Bresser or Sky Watcher models. Wife thinks they're reasonably priced and has no concept of how big they are haha

Edited by BaldyMan
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Mars is getting further away from us and will look small even in a large telescope. Being in or near opposition makes a HUGE difference when observing Mars.

Here's an example for you.

The first image was taken before opposition in August 2020 with a Celestron C11 telescope that has a 280mm primary mirror and 2800mm focal length. Mars is quite small and you can only see some details. The view visually was very much like it is in this image.

MARS_8.8.2020_VERSIO_1_Crop_small.png.9c8425f781815e7e6123ddd543359a25.png

Here's an image I took in October, a few days after opposition, with a much smaller Celestron C8. The difference in the level of detail is quite remarkable. You can see Valles Marineris and even the largest volcano in the solar system, Olympus Mons.

Mars_16_10.2020_23_33_CPC_800.png.aaeb24b7d7f8cc79df09ed64358ceb14.png

Visually, I could see a lot of detail with my C8 telescope during the opposition. However, the last time I looked at the red planet was in January, and I was barely able to see the polar ice cap and some dark features. Mars was very small even in my C8 telescope.

My point is that this is just how the solar system works. Luckily there is a lot to see in the night sky and Mars will eventually be back again. 🙂

Edited by AstroFin
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On 08/02/2021 at 09:24, Goldenmole said:

Is this just how Mars looks through a telescope like mine?

I think it mainly depends on your expectations (and to a lesser extent on your equipment). Planets will never fill the field of view or show details you see on pictures: they are always (very) small disks - most likely much smaller that you'd expect, and it takes a lot of experience to discern surface details on Mars.

That said, Mars is well past opposition so conditions are not very favourable at the moment. But if you look closely and compare the view of Mars with that of a bright star, you'll see that the planet is not a pinpoint of light but a small disk, and you might even see that Mars is not 'full' at the moment but a bit 'gibbous'. Just keep on trying, it's worth it!

Edited by Waddensky
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2 hours ago, BaldyMan said:

I'll be investing in an 8" dobsonian like the Bresser or Sky Watcher models. Wife thinks they're reasonably priced and has no concept of how big they are haha

I have an 8" SW Dob and i love it. My wife had no clue how big it will be and was quite surprised when fully assembled, but it sits nicely at the corner of the sitting room, and once i started showing her things through it, she completely ignores its presence there. Yes it is big but it does not take space since it sits upright.

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3 hours ago, Peter Drew said:

@Goldenmole.  Your telescope has an erecting prism diagonal, the prism will show a bar across the middle when used at night, if you plan to replace it make sure you get a standard 90 degree star diagonal.     🙂

Wait. So the strange black bar I see is due to it being an erecting prism and not a manufacturing issue? I only notice it when I focus in a certain amount.

I'll be sure to buy a star diagonal then for night time observations 

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