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I have been trying to see surface features on the disk of Jupiter with my Natgeo 76/700 EQ1 but it does not appear to be too clear. So I was wondering:

  1. What kind of image I should expect from this telescope?
  2. If my experience doesn't match expectations, what are some likely reasons?

1It's a 76 mm f/9.2 Newtonian reflector

uhoh
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Rudra Singh
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    You can see Jupiter with the naked eye! See http://www.deepskywatch.com/Articles/what-can-i-see-through-telescope.html for ideas of what level of detail you can see. This is "small and cheap". – James K Nov 07 '22 at 18:03
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    What are the focal lengths of the eyepieces that you've tried using? Also I'm not familiar with that telescope - is it a refractor or a reflector? – Aaron F Nov 07 '22 at 18:43
  • @RudraSingh Welcome to Astronomy SE! I've made some edits to clarify your question and to address some of the comments. I'm pretty sure that by "See Jupiter" you mean visually resolve features on the planet. The short answer is that we just can't expect to see that much through a small telescope to begin with, and atmospheric effects (depending on time of night, weather, etc.) can make things even worse. While seeing the surfaces of planets is often the first reason we buy telescopes, there are a lot of other interesting things better suited to small telescopes. – uhoh Nov 07 '22 at 22:15
  • @RudraSingh Were you able to see any of the for big Galilean Moons of Jupiter? Did they move from one night to the next? Have you spotted the Orion nebula yet? Amateur observing needs a bit of patience and some research and observation planning during the day to be rewarding at night. For most objects with this size telescope it's mostly "Okay I've seen it with my own eyes, yay!" even though it's fuzzy, then we can look at published images from big telescopes (or even space telescopes) and appreciate them better. – uhoh Nov 07 '22 at 22:21
  • Depending on your location, you may be able to see the lunar eclipse tonight. Totality (when the Moon is very dark red or almost invisible) is between 10:17 and 11:41 UTC, and the otherwise bright full Moon will look more like this. – uhoh Nov 07 '22 at 22:23
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    It a reflector telescope, has a clear aperture of 75.2 mm, focal length of 694.2 mm, Barlow is 3x – Rudra Singh Nov 08 '22 at 03:36
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    The lenses have a focal length of 8 mm, 12.5 mm and 30 mm. – Rudra Singh Nov 08 '22 at 03:36
  • I'd guess that on a clear night with good seeing, Jupiter high above the horizon, a 76mm mirror 8mm eyepiece and 3x barlow, you'd just about make out the equatorial belts. – Dave Gremlin Nov 09 '22 at 11:45
  • Probably you will see Jupiter's equatorial belts. I definitely see them with 114mm reflector. The problem is that usually seeing conditions are fluctuating rapidly. I see the belts for a couple of seconds, and then the conditions deteriorate and I don't see them, and then again.. So be prepared to wait a little. Good luck! – Heopps Nov 09 '22 at 12:54

2 Answers2

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Nobody can see the surface of Jupiter, or Saturen, or Uranus, or Neptune.

Jupiter has no surface. the Atmosphere of Jupiter just gets denser and denser with depth until it beceomes denser than the center of the Earth, without having any solid surface layer.

What looks like the surface of jupiter in photos is actually a more or less opague cloud layer in the upper atmosphere.

You can see Jupiter as a very bright dot in the sky without a telescope or binoculars.

With binoculars you should be able to see jupiter as a tiny bright circle in the sky instead of a dot. And probably also a few tiny specks of light beside Jupiter. Those specks of light will be the four large moons of Jupiter. And you should be able to watch them move relative to Jupiter and each other from night to night.

With a telescope Jupiter will look bigger, depending on the focus and mangification settings. You might be able to see the colored bands in Jupiter's atmopshere and maybe the Great Red Spot. And the four main moons will look much brighter.

And more experienced amateur observers will be able to tell you more about wha tyu could see.

M. A. Golding
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You can see some large details

With a 76mm scope and a decent eyepiece you should be able to see the bands of Jupiter, the Great Red Spot (if it's rotated to the side facing us), and the Galilean moons (Io, Europa, Ganymede, Callisto). The moons will be points of light like stars, but you'll be able to see their positions with respect to Jupiter as they orbit.

You will need decent 'seeing' (not too much atmospheric turbulence) and an eyepiece that gives you enough magnification if you want to see the bands or the GRS. It will help if Jupiter is very high in the sky. The surface details will be quite faint and may be difficult to see because of low contrast on a small inexpensive scope.

The Galilean moons are your best bet for first observation. Galileo discovered the moons with a primitive 26mm scope.

Dan Hanson
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