{"product_id":"explore-scientific-sidara-nano-90-refractor-telescope","title":"Explore Scientific Sidara Nano 90mm Refractor Telescope and Alt-Azimuth Mount with Sky Assist","description":"\u003ch2\u003eProduct Overview\u003c\/h2\u003e\n\u003cp\u003eThe Sidara Nano 90 is the entry point to Explore Scientific's Sidara range: a 90 mm refractor of 700 mm focal length, which works out to about f\/7.8, on the compact Nano alt-azimuth mount with a slow-motion control system, a tripod, and eyepieces and accessories. Explore Scientific describes it as \"a compact and highly approachable system\" that gives \"a balanced combination of magnification and clarity,\" and says it is \"well suited for observing the Moon, planets, and brighter deep sky objects, offering sharp and stable views.\" It carries vendor item number ES-AR90700-MAZ-NANO and is the lightest and simplest package in the series.\u003c\/p\u003e\n\n\u003ch2\u003eWho It's For\u003c\/h2\u003e\n\u003cp\u003eThis is the one to buy when portability and simplicity matter more than aperture, and it is the most realistic gift telescope in the range. Ninety millimetres is a genuine, useful aperture rather than a toy: it will show the Moon in real detail, Saturn's rings unmistakably, Jupiter's two main cloud belts and its four bright moons, the phases of Venus, the Orion Nebula, the Pleiades, the double cluster in Perseus, and the brighter globular clusters as soft round glows. That list is enough to keep a curious beginner busy for years. What it will not do is compete on faint deep sky objects. Galaxies beyond the very brightest will be difficult or invisible from a suburban garden, and even under dark skies they are faint grey patches. Nothing at this aperture shows colour in nebulae, because human colour vision does not operate at those light levels, so a gift recipient expecting the images they have seen online needs that expectation adjusted before the box is opened rather than after.\u003c\/p\u003e\n\u003cp\u003eSet against the larger telescopes in this group, the trade is honest and worth understanding. The 102 mm Essential refractor collects about a third more light, and the 150 mm Plus reflector collects nearly three times as much, so each step up genuinely shows more. But light grasp is only half the story for a first telescope. The Nano 90 is the one that is light enough to carry outside on a whim, quick enough to set up that a clear half hour is worth using, and simple enough that nobody has to be taught anything before they look through it. A telescope that gets used every clear week shows its owner far more over a year than a bigger one that stays in a cupboard. There is also a real optical advantage hiding in the specification: at roughly f\/7.8 this is the slowest, most gently corrected refractor in the range, so it shows noticeably less violet fringing on the Moon and on bright planets than the faster 102 mm and 127 mm achromats do. Small aperture, but clean images.\u003c\/p\u003e\n\n\u003ch2\u003eKey Features \u0026amp; Design\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e90 mm aperture refractor with a 700 mm focal length, giving a relatively slow f\/7.8 system with well-controlled colour error.\u003c\/li\u003e\n\u003cli\u003eCompact Nano alt-azimuth mount with a slow-motion control system for smooth tracking, described by Explore Scientific as \"making it easier to follow objects across the sky.\"\u003c\/li\u003e\n\u003cli\u003eThe lightest and most portable package in the Sidara line, intended to be carried out and set up quickly.\u003c\/li\u003e\n\u003cli\u003eSky Assist compatibility, which Explore Scientific says helps \"guide users to celestial targets, reducing the learning curve and improving the overall experience.\"\u003c\/li\u003e\n\u003cli\u003eSealed refractor tube with no mirrors to align, so there is no collimation and no maintenance routine.\u003c\/li\u003e\n\u003cli\u003eSupplied complete: 90 mm refractor tube, Nano mount, tripod, and eyepieces and accessories.\u003c\/li\u003e\n\u003cli\u003eUsable for daytime terrestrial viewing with an appropriate erecting diagonal, which reflectors cannot manage.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eOptical Design\u003c\/h2\u003e\n\u003cp\u003eFocal ratio is the quiet hero of this specification. A doublet achromat brings two wavelengths to a common focus and leaves the rest slightly astray, and the size of that residual error shrinks as the telescope gets slower, which is to say as the focal ratio number gets larger. At f\/7.8 the 90 mm objective here is meaningfully better corrected than the faster achromatic refractors elsewhere in the Sidara line, so bright objects show a cleaner edge with less of the violet halo that faster achromats produce. The 700 mm focal length also gives comfortable magnifications without extreme eyepieces: a 25 mm eyepiece yields about 28x for wide, easy views, and a 10 mm yields about 70x, which is a good working power for the Moon and planets. The realistic upper limit for a 90 mm aperture is somewhere around 150x, and atmospheric steadiness rather than the optics will usually be what stops you. Mechanically, the Nano mount moves in altitude and azimuth, the two directions a beginner instinctively expects, and its slow-motion control lets you follow an object as the Earth's rotation carries it out of the field without bumping the tube off target, which is the difference between comfortable viewing and constant re-aiming above about 50x.\u003c\/p\u003e\n\n\u003ch2\u003eRecommended Uses\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eLunar observing, where 90 mm of clean aperture shows craters, mountain ranges and terminator shadows in detail.\u003c\/li\u003e\n\u003cli\u003ePlanetary viewing of Saturn, Jupiter and Venus at moderate magnification.\u003c\/li\u003e\n\u003cli\u003eBright star clusters and the brighter nebulae from suburban or semi-rural skies.\u003c\/li\u003e\n\u003cli\u003eTravel and grab-and-go observing, including camping trips and cottage weekends where bulk is the deciding factor.\u003c\/li\u003e\n\u003cli\u003eDaytime terrestrial and wildlife viewing with a suitable erecting diagonal.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eCompatibility and Accessory Notes\u003c\/h2\u003e\n\u003cp\u003eThe package includes eyepieces and accessories, but Explore Scientific does not itemise them, publish the focuser barrel size, or state the finder and diagonal supplied. That matters here more than usual, because a 90 mm refractor is the size where a single good eyepiece changes the experience noticeably. If you want a higher-power eyepiece in the 6 mm to 9 mm range for planetary nights, or an erecting prism for daytime use, contact our team in Bolton and we will confirm whether the focuser takes 1.25-inch fittings before you order anything. A neutral density Moon filter is a modest and worthwhile addition. If you are thinking about whether this tube could later ride on a larger mount, or whether the Nano head could carry a heavier telescope, that is genuinely model-dependent and Explore Scientific has not published a load rating, so ask us and we will check rather than guess.\u003c\/p\u003e\n\n\u003ch2\u003eGood to Know Before You Order\u003c\/h2\u003e\n\u003cp\u003eExplore Scientific publishes no shipping weight for this item, so we are confirming it on our own scales before the listing goes live. That is why it is currently unpublished. Contact us and we will give you a shipping figure for your address. Beyond that, be realistic about the mount rather than the optics. The Nano is the lightest head in the Sidara range and is matched to this small tube; a light mount is easy to carry but will also settle more slowly after you touch the focuser, so expect a second or two of vibration at higher powers. That is normal for a compact package at this size. The vendor publishes no specification table and no itemised accessory list for this telescope, so we are not going to state what is in the box beyond what they say. This is a manual mount with no motors and no GoTo, and it is not intended for astrophotography beyond casual phone shots of the Moon.\u003c\/p\u003e\n\n\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003eWhat is Sky Assist and what does it require?\u003c\/strong\u003e Explore Scientific describes it on this package as guidance that helps \"guide users to celestial targets, reducing the learning curve and improving the overall experience.\" On their motorised Sidara Pro mounts they say Sky Assist lets users \"select targets and allow the mount to move the telescope into position,\" but the Nano is a manual mount, so here it points you toward a target and you move the telescope by hand. Explore Scientific has not published what the feature needs in order to run or how it is configured, and we would rather say so than describe features they have not documented. Contact us and we will confirm the current details with the distributor.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eIs 90 mm big enough to be worth buying?\u003c\/strong\u003e For the Moon, the planets and bright clusters and nebulae, comfortably yes. For faint galaxies and dim nebulae, no, and you should step up to the 130 mm or 150 mm reflector if those are what you are after. Most beginners spend their first year on the objects a 90 mm handles well.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eIs this a good telescope for a child?\u003c\/strong\u003e It is the best choice in this range for that. It is light enough for a child to help carry, there is no collimation to learn, and the eyepiece sits at a manageable height. Expect an adult to handle setup and finder alignment for the first few sessions.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eHow does it compare with a good pair of binoculars?\u003c\/strong\u003e It shows considerably more. Binoculars are better for wide star fields and are more portable still, but they cannot deliver the magnification needed to show Saturn's rings or lunar crater detail, which is where this telescope earns its place.\u003c\/p\u003e\n\n\u003ch2\u003eBottom Line\u003c\/h2\u003e\n\u003cp\u003eThe Sidara Nano 90 is a small telescope that is honest about being one, and it does the things beginners actually spend their time on very well: the Moon, the planets, bright clusters, and getting outside quickly. Its slower focal ratio gives it cleaner images than its bigger achromatic siblings, which is a fair consolation for the aperture. If you are not sure whether to start here or step up to the 102 mm or 130 mm, contact our team in Bolton and we will help you match it to your skies and to who will be using it.\u003c\/p\u003e","brand":"Explore Scientific","offers":[{"title":"Default Title","offer_id":53958722093167,"sku":"ES-AR90700-MAZ-NANO","price":415.95,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/sidara_nano_90_v2.jpg?v=1785960942","url":"https:\/\/ontariotelescope.com\/products\/explore-scientific-sidara-nano-90-refractor-telescope","provider":"Ontario Telescope and Accessories","version":"1.0","type":"link"}