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What happens when the sun releases energy to create prominences, flares, mass ejections, and tsunamis, and how can those events affect us on ...

Description Converts 60mm thread to 53mm thread Available for FL and ED OTAs. Specs Optical Path Length 4mm Weight 22g Warranty Vix...

Description Converts 53mm thread to 43mm thread Available for FL and ED OTAs. Specs Optical Path Length 3mm Weight 19g Warranty Vix...

Essential for Time-Lapse Photography Specs Connecting to the POLARIE U 2.5mm stereo mini plug Connecting to the camera Accessory remote t...

Essential for Time-Lapse Photography Specs Connecting to the POLARIE U 2.5mm stereo mini plug Connecting to the camera Multi-connector pl...

In order to unlock the mysteries of the corona, but also to protect a society that is increasingly dependent on technology from the threats of s...

Today, astronomers and researchers, both professional and amateur, have unprecedented access to online science data, allowing a greater unders...

The first positive detection of water ice on Mars was from the Phoenix Lander that scraped away some surface dust to reveal pristine ice belo...

Humans have been obsessed with the measurement of time perhaps as far back as 100,000 years ago. Dr. Barth guides us through evidence of meas...

Stromatolite fossils are a dominant record of life for most of Earth’s history prior to the appearance of complex, multicellular organisms. S...

In 2019, NASA announced that an international team had found sugars essential to life in meteorites. The discovery added to the growing list o...

Aside from Earth, Mars is the most studied ecosystem by scientists today. With the process of collecting data from rovers and orbiting satelli...

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...

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...

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...

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...