Under $500

Signed by the Author for Delivery at the Arizona Dark Sky Star Party The autobiography of Mike Weasner describes his journey through the Universe t...

This is part one of a two-part program on the Hubble Constant and the controversy about different values for this keystone unit of measurement. In...

This is part two of a two-part program on the Hubble Constant and the controversy about different values for this keystone unit of measurement. In...

Planetary nebulae are some of the most beautiful and intriguing deep sky objects in the Milky Way. They reveal the expanding, glowing shells of th...

Features Reflection / Transmission LED Illumination 3 Lenses: 4X / 10X / 40X Dust cover Included: Permanent slides, Slides, Microscopy instrument...

From its discovery in 1846 until Clyde Tombaugh's discovery of Pluto in 1930, Neptune was the farthest-known planet. Now with the controversial re...

Features 4K Wifi Waterproof Action Camera Waterproof Case Rechargeable Battery USB Cable Remote Handlebar/Pole Mount Frame Mount Straps Release B...

Gravity is the weakest of the four fundamental forces, it causes causes mutual attraction between all things with mass or energy. It is  approximat...

 The European Space Agency’s Exobiology on Mars (ExoMars) program has included a series of missions designed to study the potential for...

In cosmology, the anthropic principle involves any structure of the universe, the values of the constants of nature, or the laws of nature that ha...

Have you ever wondered how hard it can be to merge two black holes? Well it actually is a lot harder than you think. You would think that because t...

We hear the phrase "You can't prove that!" all the time. But is it a valid criticism? On this episode of How Do You Know Dr Daniel Barth will defi...

Description This device allows you to attach the Explore Scientific Hybrid 2N1 finder base to our Giant Binocular Series, allowing easy pointing/a...

Suitable for both the eVscope eQuinox and the eVscope 2 Features Built-in foam inserts precisely match the shape of your eVscope Internal strap ...

Features Wide-view color VA display Moon phase display Barometer with weather forecast 6 kinds of dynamic weather forecast icons (Sunny, Clear to...

Features Binocular-style eyepiece design keeps both hands free for working on a specimen while observing Angled eyepiece barrels provide a comfor...

Features Study specimens in stages using three magnification powers ranging from 300x to 1200x. Use the projection eyepiece to trace images to an...

Features Waterproof National Geographic Harness 283ft field of view at 1000 yards Carrying case and lens covers included Description These ver...

Features 1.25 "linear polarization filter Socket with 1.25 "filter thread Also suitable for Lunt Herschel wedges Description Simple linear 1.25...

A Map of the Classical Albedo Features of Mars Produced by Carlos Hernandez. Not all features noted on the map are visible to an observer at any...

Features Ample 70mm aperture will reveal lots of lunar details, planetary features like Jupiter’s cloud belts or Saturn’s rings and some of the b...

Features Pocket Camera - Capture engaging content to share with friends, family and followers with this compact 1080P HD camera that slips easil...

Get the National Geographic Carbon Trekking Poles Set ($59.99) for FREE, when purchasing 10x42 Waterproof Performance Roof Binoculars. To activate...

Features Waterproof up to 32 ft LED light and strong pulse vibration for metal detection Uncover coins, jewelry and precious metals on land or un...

Features Three objective lenses mounted on a rotating turret provide magnifications of 100x, 400x and 1200x. Includes Prepared and blank slides, ...

Description Discover The World Around! Your ExploreOne 6x21 Binoculars are the perfect companion for countless outdoor adventures. With these dura...

AA Battery Holder Powers Truss-Tube Dobsonian Fans   The AA battery holders for the Explore Scientific truss-tube Dobsonian telescopes with fans us...

Features Very high sharpness and contrast across the entire field of view Almost no color defects due to lanthanum glass Twist-Up eyecup for peop...

Features Very high sharpness and contrast across the entire field of view Almost no color defects due to lanthanum glass Twist-Up eyecup for peop...

Features Very high sharpness and contrast across the entire field of view Almost no color defects due to lanthanum glass Twist-Up eyecup for peop...

Features Very high sharpness and contrast across the entire field of view Almost no color defects due to lanthanum glass Twist-Up eyecup for peop...

Features Very high sharpness and contrast across the entire field of view Almost no color defects due to lanthanum glass Twist-Up eyecup for peop...

Features Very high sharpness and contrast across the entire field of view Almost no color defects due to lanthanum glass Twist-Up eyecup for peop...

Features Enhanced Vision Technology Unlock the secrets of Solar Activity Observe the Sun in less than 2 Minutes Safely Experience With Your Fami...

Description For photography of nebula or star clusters This reducer is designed to shorten the effective focal length. This allows shorter exposur...

Features Special mount atop telescope tube allows users to attach their device to the telescope and easily locate constellations and planets in t...