Morrison Planetarium California Academy of Sciences

The NexStar 5SE runs on eight AA batteries (not included) to power the mount. When the mount is in use, these batteries drain fast, offering an average of only two to four hours of power. If you’re out for an entire evening, the mount can eat through your battery supply. It’s common practice, however, to use batteries only as a backup to an external battery-power source, so the scope’s operation will not be interrupted. These criteria can be said to correspond to the strength and power of the telescope. And yet, as Daniel Mounsey warned us, one mistake beginners make when choosing a telescope is thinking that bigger is always better when it comes to aperture.
If you have high hopes to examine the stellar disks in detail and find out how the stars in the Ursa Major constellation differ from the stars in the Little Dipper – slow your roll here. The closest star to us, Proxima Centauri, is 7 times smaller than the Sun and is 4 light years away. In order to see it, you would need a telescope with a lens 140m in diameter, which is impossible in terrestrial conditions. The largest of the currently existing optical telescopes, the Grand Canary Telescope (Gran Telescopio Canarias), has a mirror of only 10.4 meters in diameter. Therefore, in Looking for the best telescope under 200 – Look no further! Take a look at the best telescopes under £200 right here! , we will only be able to see the stars as glowing blurred spots, surrounded by concentric rings. For observing different types of objects there are different optical requirements.
Telescopes give you a superior view of the heavens, but are less portable, less durable, and slightly more difficult to use than a spotting scope. Also as @MikeG suggests, if you telescope has a finder scope, it’s really worth your while to take some time to align the finder to the main telescope, perhaps using an object on the horizon during the day, or the Moon. Neptune is just slightly smaller than Uranus so it’s a fairly large planet. But at 2.8 billion miles from the Sun that means it’s
apparent size is only half of Uranus. “Should I regularly clean my eyepieces and telescope mirrors?” Absolutely not.
Neptune is notorious for rapidly changing cloud belts and spots and now Uranus is growing active as sunlight shines more directly on its equator. Recent amateur photography has improved to the point where some large features, such as a bright polar hood on Uranus, have been photographed. A magnification of at least 500x for Uranus and 900x for Neptune along with a yellow-green (Wratten #11) filter are required in order to have a chance at photographing any detail. Uranus is generally 3.7 arcseconds across and shines around magnitude +5.7 and Neptune is generally 2.3 arcseconds across and shines around magnitude +7.8. The planets appear distinctly different with Uranus having a rich turquoise hue while Neptune is a chilly, icy-blue disc. During those times of the year, the path the planets follow, the ecliptic, is nearly perpendicular to the horizon.
If thermal equilibrium is not reached, you will see a lot of distortion and turbulence through the eyepiece. But when paired with a scope whose focal length is 1,500 mm, the magnification will be 150x. As you can see, even with a small telescope, the highest useful magnification is pretty high to reach the limits of the seeing conditions. For example, a small 4” telescope will give you 200x useful maximum magnification.
Mercury and Venus, the two planets closer to the sun than Earth, are plainly visible to the naked eye. Venus, in fact, is by far the brightest object in the sky other than the sun and the moon, which of course occupy unique places in the hierarchy of observable astronomical objects. Telescopes with a 4” aperture would be good enough for kid’s purposes.