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The French mathematician and astronomer, Edouard Roche, is most famous for his work on celestial mechanics and his discovery of t...

We all know that the gravitational field of any moon causes tides on its home planet. The height of the tide for a moon also depends upon the natur...

In August of 2006 the International Astronomical Union famously downgraded Pluto, which was considered the 9th planet in our solar system, to be re...

If you study science long enough, you eventually discover that Galileo was right about the constantly changing nature of scientific knowledge. Y...

There is a misconception that ‘doing real astronomy’ is difficult and expensive, only highly trained and generously funded people can do it; ...

Humans have attempted to map the stars in the sky since antiquity.  The earliest Western catalog of stars was created by the Greek astronomer...

  Fact, Hypothesis, Theory There is a distinct hierarchy in science that distinguishes facts, hypotheses, and theories. We misunderstand and ...

Mars - The Dying Planet Astronomers have been exploring Mars with telescopes for four centuries, and the fascination of the red planet with its ...

Russian biologist A. P. Oparin and Scottish biologist J. B. S. Haldane both proposed an early reducing atmosphere on Earth consisting of hydr...

The Viking Experiments In the early 1960’s, long before humans had left low Earth orbit, NASA was planning a mission to Mars that would soft-...

Sketching Saturn: The Box and Rectangle Method The first discoveries the system of the rings and moons around Saturn predate photographic tec...

Saturn has 7 major moons and more than 70 known moonlets. For the amateur astronomer, detecting and identifying these major moons is a challe...

We normally think of galaxies as some of the largest, brightest structures in the universe – but that isn’t always true. It is star formation t...

Ultra-diffuse galaxies are generally quenched dwarf galaxies with no gas reservoirs, they are therefore unable to form new stars; as a result, ...

The universe has always been mysterious and strange to us, but in fact it may be stranger than we can ever fathom. In this episode of How Do You...

In the second part of Dr. Barth's discussion on dark matter, he touches on why did galaxies form, the missing matter problem, and the Great Attr...

In this episode, Dr. Barth discusses the the difference between persuading someone to accept your opinion in an argument and arguing from eviden...

The creation of Earth's Moon is an age old question. There are pre-Apollo mission theories, of which three of the most popular ones will be d...

It's estimated that we will colonize Mars by 2050. The challenges to make it happen are daunting.  Dr. Barth touches on some of the problems tha...

Dr. Daniel Barth returns with the 33rd episode of 'How Do You KNOW?' to discuss the Three Ring Theory that explains the formation of our solar s...

Dr. Daniel Barth gives us an overview of and will answer your questions about the James Webb Space Telescope in this 34th Episode of How Do You ...

Features Projection Clock Radio Controlled Digital Time Display Clock with NIST WWVB Receiver 180 Degree Rotatable Projection Head Time  Project...

Dr. Daniel Barth gives us an overview of and will answer your questions about Lagrange Points in this 35th Episode of How Do You KNOW? https://e...

Dr. Daniel Barth gives us an overview of and will answer your questions about what happens When Asteroids Strike in this 36th Episode of How Do ...