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Astronomy Minute

Astronomy Minute

By Ata Sarajedini

Learn the basics of astronomy in one-to-two minute packets of concise information about specific topics. You are a busy person with a short attention span, and you want to learn about astronomical topics in a short amount of time. Your host Professor Ata is a PhD research astronomer and astrophysicist and a noted authority on stellar and galactic astronomy. I welcome your feedback at ata.sarajedini@gmail.com. See the web site astronomyminute.org for more. The podcast logo is courtesy of Zachary Greathouse and shows a globular cluster photo taken by the author with the Hubble Space Telescope.
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What is Meant by Spiral Nebula?
What is Meant by Spiral Nebula?
A brief historical summary of what we mean when we refer to "Spiral Nebulae." 
01:08
June 19, 2022
What is the Big Crunch?
What is the Big Crunch?
A brief description of what will happen if the universe stops expanding and collapses back on itself - this is known as the Big Crunch.
01:38
May 31, 2022
What are the Basic Properties of Astronomical Objects?
What are the Basic Properties of Astronomical Objects?
A brief description of the basic properties of astronomical objects such as mass, radius, distance, luminosity, and temperature.
02:15
May 18, 2022
What is the Local Group of Galaxies?
What is the Local Group of Galaxies?
A brief description of the Local Group of galaxies which contains the Milky Way, the Andromeda galaxy, and dozens of dwarf galaxies all gravitationally bound to each other.
01:19
May 10, 2022
What Does it Mean to “Know” Something in Science?
What Does it Mean to “Know” Something in Science?
A brief description of what scientists mean when they say we "know" something.
01:59
April 10, 2022
How Can Atoms and Thus Matter be Mostly Empty Space?
How Can Atoms and Thus Matter be Mostly Empty Space?
A brief description of the structure of atoms - how they are mostly empty space - and why the everyday objects you use don't collapse and fall in on themselves.
01:57
April 08, 2022
What are Interacting Galaxies?
What are Interacting Galaxies?
A brief description of what we mean when we talk about interacting galaxies.
01:35
March 09, 2022
How do the Sun and Other Stars Shine?
How do the Sun and Other Stars Shine?
A brief description of nuclear fusion, which is the process by which stars produce light so that they can shine.
01:50
March 09, 2022
What are Giant Molecular Clouds?
What are Giant Molecular Clouds?
A brief description of giant molecular clouds and why they are important for stars.
01:08
February 25, 2022
How do We Know that the Milky Way Galaxy is Spiral in Shape?
How do We Know that the Milky Way Galaxy is Spiral in Shape?
A brief description of the observational evidence we have supporting our assertion that the Milky Way galaxy is spiral in shape. 
01:17
February 24, 2022
What is Meant by the 21 Centimeter Radiation of Hydrogen?
What is Meant by the 21 Centimeter Radiation of Hydrogen?
A brief description of the 21 centimeter radiation (light) that the Hydrogen atom emits and the mechanism behind this emission.
02:27
February 04, 2022
How are Neutron Stars and Pulsars Related?
How are Neutron Stars and Pulsars Related?
A brief description of what astronomers mean when they say that "all pulsars are neutron stars but not all neutron stars are pulsars."
01:44
December 18, 2021
What is a Neutron Star?
What is a Neutron Star?
A brief description of neutron stars, which are essentially the end state of massive stars some of which become pulsars.
01:59
August 03, 2021
What is a White Dwarf Star?
What is a White Dwarf Star?
A brief description of a white dwarf star, which is the end-state of a star that is less than 8 times the mass of Sun. 
01:50
July 28, 2021
How do We Know the Ages of Stars?
How do We Know the Ages of Stars?
A brief description of how we use the HR Diagram and the main sequence to measure the ages of stars in groups and clusters.
01:52
June 23, 2021
What is Seeing and the Resolving Power of a Telescope?
What is Seeing and the Resolving Power of a Telescope?
A brief description of seeing and the resolving power of a telescope.
01:57
June 18, 2021
Are Black Holes Cosmic Vacuum Cleaners?
Are Black Holes Cosmic Vacuum Cleaners?
A brief description of the true nature of black holes as highly localized sources of gravity and not cosmic vacuum cleaners.
01:47
June 14, 2021
What Was Here Before the Big Bang?
What Was Here Before the Big Bang?
A brief description of what we think was here before the Big Bang. Short answer is that we don't know since "Science" is not equipped to answer questions where no data or information is available.
01:41
June 11, 2021
Are UFOs Aliens From Outer Space?
Are UFOs Aliens From Outer Space?
A brief description of my personal point of view regarding the possibility that UFOs harbor extraterrestrial beings visiting Earth.
02:15
June 09, 2021
What is the Milky Way Galaxy?
What is the Milky Way Galaxy?
A brief description of the structure of the Milky Way galaxy - our galactic home.
01:28
June 06, 2021
What is the Hubble Law?
What is the Hubble Law?
A brief description of the Hubble Law, now more formally known as the Hubble-Lemaitre Law.
01:08
June 02, 2021
What are Starburst Galaxies?
What are Starburst Galaxies?
A brief description of starburst galaxies and why they are in star formation overdrive.
01:10
June 01, 2021
Is Science Absolute?
Is Science Absolute?
A brief description of whether the findings of science are _absolutely_ true. It could also have been entitled “Are Scientific Results Absolute?” and “Is the Scientific Method Absolute?”
01:43
May 26, 2021
What is Meant by Dimensional Analysis?
What is Meant by Dimensional Analysis?
A brief description of what is meant by dimensional analysis. In short, the final units in a calculation must be correct for the calculation to be correct.
02:23
May 17, 2021
What are Sunspots and the Sunspot Cycle?
What are Sunspots and the Sunspot Cycle?
A brief description of the nature of sunspots and the sunspot cycle.
01:31
May 11, 2021
What is Meant by Einstein’s Theory of Relativity?
What is Meant by Einstein’s Theory of Relativity?
A brief description of Einstein’s Theories of Special Relativity and General Relativity?
01:35
May 11, 2021
A Description of the Mathematical Basis of Cause-and-Effect
A Description of the Mathematical Basis of Cause-and-Effect
A brief description of how we mathematically relate cause and effect in science. A short description of the equation of a straight line, y=m*x + b is also included.
02:57
May 02, 2021
How do Lunar and Solar Eclipses Happen?
How do Lunar and Solar Eclipses Happen?
A brief description of the different kinds of lunar and solar eclipses and how they happen.
01:49
April 12, 2021
What do I Need to Know About Planet Earth?
What do I Need to Know About Planet Earth?
A brief description of what makes Earth unique from the other terrestrial planets - active plate tectonics, liquid water, a significant atmosphere, and the rich diversity of life.
01:43
April 07, 2021
So You Want to be a Professional Astronomer?
So You Want to be a Professional Astronomer?
Some advice for anyone wanting to pursue professional astronomy/astrophysics as a career choice.
01:53
March 30, 2021
How do Atoms Absorb and Emit Light?
How do Atoms Absorb and Emit Light?
A brief description of how atoms absorb and emit particles of light known as photons based on the Bohr Model of the atom. This leads directly to the creation of absorption and emission lines in the spectra of stars.
02:23
March 24, 2021
What are Some Well-Known Deep Sky Objects?
What are Some Well-Known Deep Sky Objects?
A brief description of some deep sky objects whose names you may have heard of in popular culture.
02:02
March 15, 2021
What is Meant by the Retrograde Motion of the Planets?
What is Meant by the Retrograde Motion of the Planets?
A brief description of what is meant by retrograde motion of the planets in the Solar System.
01:53
March 12, 2021
What Professional Organizations Support the Work of Astronomers?
What Professional Organizations Support the Work of Astronomers?
A brief description of the professional organizations that support the work of astronomers in North America and worldwide.
01:37
March 10, 2021
How do Astronomers Obtain Their Observations of the Sky?
How do Astronomers Obtain Their Observations of the Sky?
A brief description of the process used to allocate telescope time to professional astronomers interested in addressing scientific questions.
01:40
March 09, 2021
How do Astronomers Disseminate Their Scientific Research Results?
How do Astronomers Disseminate Their Scientific Research Results?
A brief description of how astronomers disseminate their research results to other scientists.
02:15
March 03, 2021
What is Meant by Metal Abundance or Metallicity?
What is Meant by Metal Abundance or Metallicity?
A brief description of how we quantify the amount of metals in a star, i.e. how much of the star is composed of elements heavier than Helium, using a logarithmic quantity designated as Fe over H, or simply [Fe/H].
02:03
February 24, 2021
What is Meant by Light Pollution?
What is Meant by Light Pollution?
A brief description of light pollution and why astronomers are so concerned about its effects on the brightness of the night sky.
01:23
February 24, 2021
Is Science the Only Path to the Truth?
Is Science the Only Path to the Truth?
A brief treatment of the limitations of science as pertains to seeking the truth in other areas outside of the natural world.
01:23
February 19, 2021
Which Notable Objects are in the Constellation of Virgo?
Which Notable Objects are in the Constellation of Virgo?
A brief description of the notable celestial objects located in the constellation of Virgo.
01:35
February 14, 2021
Which Notable Objects are in the Constellation of Ursa Major?
Which Notable Objects are in the Constellation of Ursa Major?
A brief description of the notable celestial objects located in the constellation of Ursa Major.
01:10
February 14, 2021
Which Notable Objects are in the Constellation of Tucana?
Which Notable Objects are in the Constellation of Tucana?
A brief description of the notable celestial objects located in the constellation of Tucana.
00:57
February 12, 2021
Which Notable Objects are in the Constellation of Triangulum?
Which Notable Objects are in the Constellation of Triangulum?
A brief description of the notable celestial objects located in the constellation of Triangulum.
01:28
February 11, 2021
Which Notable Objects are in the Constellation of Scorpius?
Which Notable Objects are in the Constellation of Scorpius?
A brief description of the notable celestial objects located in the constellation of Scorpius.
01:19
February 11, 2021
Which Notable Objects are in the Constellation of Ophiuchus?
Which Notable Objects are in the Constellation of Ophiuchus?
A brief description of the notable celestial objects located in the constellation of Ophiuchus.
01:22
February 10, 2021
Which Notable Objects are in the Constellation of Monoceros?
Which Notable Objects are in the Constellation of Monoceros?
A brief description of the notable celestial objects located in the constellation of Monoceros.
01:04
February 10, 2021
Which Notable Objects are in the Constellation of Leo?
Which Notable Objects are in the Constellation of Leo?
A brief description of the notable celestial objects located in the constellation of Leo.
01:14
February 07, 2021
The Many Facets of Astronomy and the Lure of the Night Sky
The Many Facets of Astronomy and the Lure of the Night Sky
A brief description of the many facets of astronomy and what attracts us to study and gaze upon the night sky.
02:08
January 29, 2021
What is the Relation Between Local Sidereal Time and Local Time?
What is the Relation Between Local Sidereal Time and Local Time?
A not-so-brief description of the relation between Local Sidereal Time and Local Time. For the purposes of this podcast, Local Time, Local Apparent Time, and Standard Time are largely interchangeable.
02:42
January 28, 2021
What is the Equation of Time?
What is the Equation of Time?
A brief description of the definition of the Equation of Time.
01:16
January 26, 2021
What is Meant by Local Apparent Time?
What is Meant by Local Apparent Time?
A brief description of the definition of Local Apparent Time. 
02:09
January 26, 2021
Which Notable Objects are in the Constellation of Dorado?
Which Notable Objects are in the Constellation of Dorado?
A brief description of the notable celestial objects located in the constellation of Dorado.
01:14
January 23, 2021
What is Meant by Local Sidereal Time?
What is Meant by Local Sidereal Time?
A brief description of what is meant by Local Sidereal Time. In a nutshell, Local Sidereal Time or LST is the Right Ascension of the Meridian.
01:37
January 23, 2021
What is Meant by Galactic Coordinate System?
What is Meant by Galactic Coordinate System?
A brief description of the way astronomers identify the locations of stars and other celestial objects relative to the plane of the Milky Way galaxy known as the Galactic Coordinate System.
01:11
January 22, 2021
What is Meant by Altazimuth Coordinate System?
What is Meant by Altazimuth Coordinate System?
A brief description of one of the ways astronomers identify the locations of stars and other celestial objects in the sky known as the Altazimuth Coordinate System.. 
01:02
January 22, 2021
What is Meant by Altitude and Azimuth?
What is Meant by Altitude and Azimuth?
A brief description of altitude and azimuth and how they are used to located objects in the sky. 
01:23
January 22, 2021
What is Meant by Equatorial Coordinate System?
What is Meant by Equatorial Coordinate System?
A brief description of one of the ways astronomers identify the locations of stars and other celestial objects in the sky known as the Equatorial Coordinate System.
00:60
January 22, 2021
What is Meant by Quantum Mechanics?
What is Meant by Quantum Mechanics?
A brief description of what quantum mechanics is and how it relates to other areas of physics.
01:35
January 17, 2021
How do We Know the Age of the Universe?
How do We Know the Age of the Universe?
A simplified description of one method we can use to calculate the age of the universe using the Hubble Constant. 
01:49
January 17, 2021
Which Notable Objects are in the Constellation of Crux?
Which Notable Objects are in the Constellation of Crux?
A brief description of the notable celestial objects located in the constellation of Crux.
01:10
January 17, 2021
Which Notable Objects are in the Constellation of Coma Berenices?
Which Notable Objects are in the Constellation of Coma Berenices?
A brief description of the notable celestial objects located in the constellation of Coma Berenices.
01:23
January 13, 2021
Which Notable Objects are in the Constellation of Cetus?
Which Notable Objects are in the Constellation of Cetus?
A brief description of the notable celestial objects located in the constellation of Cetus.
01:25
January 13, 2021
Which Notable Objects are in the Constellation of Cassiopeia?
Which Notable Objects are in the Constellation of Cassiopeia?
A brief description of the notable celestial objects located in the constellation of Cassiopeia.
01:25
January 10, 2021
Which Notable Objects are in the Constellation of Canis Major?
Which Notable Objects are in the Constellation of Canis Major?
A brief description of the notable celestial objects located in the constellation of Canis Major.
01:23
January 10, 2021
Which Notable Objects are in the Constellation of Cancer?
Which Notable Objects are in the Constellation of Cancer?
A brief description of the notable celestial objects located in the constellation of Cancer.
01:23
January 10, 2021
Which Notable Objects are in the Constellation of Canes Venatici?
Which Notable Objects are in the Constellation of Canes Venatici?
A brief description of the notable celestial objects located in the constellation of Canes Venatici.
01:29
December 24, 2020
Which Notable Objects are in the Constellation of Centaurus?
Which Notable Objects are in the Constellation of Centaurus?
A brief description of the notable celestial objects located in the constellation of Centaurus.
01:54
December 23, 2020
Which Notable Objects are in the Constellation of Taurus?
Which Notable Objects are in the Constellation of Taurus?
A brief description of the notable celestial objects located in the constellation of Taurus.
01:10
December 22, 2020
Which Notable Objects are in the Constellation of Sagittarius?
Which Notable Objects are in the Constellation of Sagittarius?
A brief description of the notable celestial objects located in the constellation of Sagittarius.
01:28
December 22, 2020
Which Notable Objects are in the Constellation of Orion?
Which Notable Objects are in the Constellation of Orion?
A brief description of the notable celestial objects located in the constellation of Orion.
01:05
December 22, 2020
Which Notable Objects are in the Constellation of Lyra?
Which Notable Objects are in the Constellation of Lyra?
A brief description of the notable celestial objects located in the constellation of Lyra.
01:14
December 20, 2020
Which Notable Objects are in the Constellation of Hercules?
Which Notable Objects are in the Constellation of Hercules?
A brief description of the notable celestial objects located in the constellation of Hercules.
01:11
December 20, 2020
Which Notable Objects are in the Constellation of Cygnus?
Which Notable Objects are in the Constellation of Cygnus?
A brief description of the notable celestial objects located in the constellation of Cygnus, the Swan.
01:20
December 20, 2020
Which Notable Objects are in the Constellation of Andromeda?
Which Notable Objects are in the Constellation of Andromeda?
A brief description of the notable celestial objects located in the constellation of Andromeda.
01:13
December 18, 2020
What is Meant by a Deep Sky Object?
What is Meant by a Deep Sky Object?
A brief description of what is meant when astronomers refer to something as a deep sky object?
00:49
December 18, 2020
What is an Asterism?
What is an Asterism?
A brief description of how we define an asterism in the sky as distinct from a constellation.
01:32
December 16, 2020
Why do We Study Astronomy?
Why do We Study Astronomy?
A brief description of why we study the nature of the Universe. We are mainly interested in gaining knowledge about the universe for the sake of the knowledge itself.
01:34
December 16, 2020
The Universe as a Time Machine
The Universe as a Time Machine
A brief description of how the finite speed of light can be used to our advantage - allowing us to look back in time to see the history of the Universe.
01:49
December 11, 2020
How Old is the Universe, the Sun, and the Earth?
How Old is the Universe, the Sun, and the Earth?
A brief description of how old the universe is as compared with the ages of the Sun, the Earth, and how long Homo Sapiens have lived on the Earth.
01:49
December 11, 2020
What is a Light Year?
What is a Light Year?
A brief description of a light year - a unit of distance based on how far light travels in one Earth year.
01:08
December 09, 2020
What is Electromagnetic Radiation?
What is Electromagnetic Radiation?
A brief description of electromagnetic radiation - that is to say light - and how its wavelength, frequency, and energy are related.
02:08
December 04, 2020
What is Meant by the Hubble Flow?
What is Meant by the Hubble Flow?
A brief description of the term Hubble Flow in astronomy. The universe is expanding on the largest scales, and this large-scale expansion of the Universe is known as the Hubble Flow.
01:43
December 04, 2020
What is a Blackbody Curve or Planck Curve?
What is a Blackbody Curve or Planck Curve?
A brief description of Blackbody or Planck curves. In short, these curves tell us the brightness of stars of a certain temperature.
02:26
November 29, 2020
What is Precession of the Equinoxes?
What is Precession of the Equinoxes?
A brief description of the phenomenon known as Precession of the Equinoxes. 
01:37
November 29, 2020
What is Meant by the Signs of the Zodiac?
What is Meant by the Signs of the Zodiac?
A brief explanation of the zodiac and how it relates to the other constellations in the sky.
01:38
November 24, 2020
Is There Life Elsewhere in the Universe?
Is There Life Elsewhere in the Universe?
A brief order-of-magnitude description of the probability of life elsewhere in the universe beyond earth.
01:44
November 22, 2020
How Old is the Solar System?
How Old is the Solar System?
A brief description of two independent methods that give an age of 4.5 billion years old for the Solar System.
02:11
November 17, 2020
How Did Our Galaxy Form?
How Did Our Galaxy Form?
A brief description of how we think the Milky Way galaxy formed. Basically, it's a process whereby hundreds to thousands of low-mass dwarf galaxies collided and coalesced to form our our galaxy.
01:53
November 14, 2020
Is There Such a Thing as THE Dark Side of the Moon?
Is There Such a Thing as THE Dark Side of the Moon?
A brief description of why there is no such thing as the dark side of the Moon.
01:13
November 06, 2020
What is Meant by Taxonomy in Science?
What is Meant by Taxonomy in Science?
A brief description of taxonomy in science and how it is used to classify objects that are similar to each other.
01:14
November 06, 2020
What are the Magellanic Clouds?
What are the Magellanic Clouds?
A brief description of two dwarf galaxies known as the Large and Small Magellanic Clouds that are in orbit around own Milky Way galaxy .
01:59
November 06, 2020
What do I Need to Know About Isaac Newton?
What do I Need to Know About Isaac Newton?
A brief description of Isaac Newton's contributions to science and mathematics. More information is available in the podcasts entitled “What are Newton’s Laws of Motion?” and “What is Newton’s Law of Universal Gravitation?”
00:49
October 29, 2020
What do I Need to Know About Galileo?
What do I Need to Know About Galileo?
A brief description of Galileo's contributions to astronomy.
01:05
October 28, 2020
The Clockwork of the Universe
The Clockwork of the Universe
A brief description of how the motion of the Moon around the Earth, the Earth around the Sun, the Sun around the center of our galaxy, and the motion of the galaxy itself are like clockwork.
02:00
October 28, 2020
What do I Need to Know About Johannes Kepler?
What do I Need to Know About Johannes Kepler?
A brief description of Johannes Kepler's main contributions to astronomy. 
00:39
October 28, 2020
What do I Need to Know About Tycho Brahe?
What do I Need to Know About Tycho Brahe?
A brief description of Tycho Brahe's contributions to astronomy.
00:54
October 26, 2020
What do I Need to Know About Nicolaus Copernicus?
What do I Need to Know About Nicolaus Copernicus?
A brief description of the basic contributions Nicolaus Copernicus made to the science of astronomy.
01:10
October 26, 2020
How do We Know There are Planets Around Other Stars?
How do We Know There are Planets Around Other Stars?
A brief description of the techniques we use to detect the presence of planets orbiting around other stars besides the Sun. These techniques are known as Transit Photometry and Doppler Spectroscopy.
01:37
October 20, 2020
What is Meant by a Bell Curve?
What is Meant by a Bell Curve?
A brief description of the definition of a Bell Curve - also known as a Normal Distribution and a Gaussian Distribution; it is very important in the fields of statistics and probability.
02:26
October 16, 2020
What are Right Ascension and Declination?
What are Right Ascension and Declination?
A brief description of Right Ascension and Declination and how they are used to locate objects in the sky.
01:59
October 16, 2020
What Causes the Phases of the Moon?
What Causes the Phases of the Moon?
A brief description of what causes the phases of the Earth's Moon. An animation/movie linked off of the web page helps to explain the podcast.
01:59
October 05, 2020
What Causes the Seasons on the Earth?
What Causes the Seasons on the Earth?
A brief description of what doesn't cause the seasons and what we actually believe does cause them. There is also a graphic linked off the web page that helps explain this episode.
01:52
September 29, 2020
What is the Difference Between Precision and Accuracy?
What is the Difference Between Precision and Accuracy?
A brief description of the difference between precision and accuracy in astronomy.
01:53
September 27, 2020
What is Meant by an Order of Magnitude and a Logarithmic Scale?
What is Meant by an Order of Magnitude and a Logarithmic Scale?
A brief description of what we mean when we say that two numbers differ by an order to magnitude. This includes a summary of what a Logarithmic is.
02:02
September 16, 2020
Where are the Sun's Siblings?
Where are the Sun's Siblings?
A brief description of why we expect the Sun to have been formed in a multiple star system and how we are searching for the other stars formed with it.
00:55
September 14, 2020
What is the Difference Between Random Errors and Systematic Errors?
What is the Difference Between Random Errors and Systematic Errors?
A brief description of the difference between random errors and systematic errors in science.
01:41
September 09, 2020
What is Meant by the Magnitude System?
What is Meant by the Magnitude System?
A brief description of the magnitude system in astronomy including the difference between apparent magnitude and absolute magnitude.
01:56
September 04, 2020
What is the Kelvin Temperature Scale?
What is the Kelvin Temperature Scale?
A brief description of the Kelvin temperature scale as compared with Fahrenheit and Celsius.
01:22
September 01, 2020
What are Comets and Meteor Showers?
What are Comets and Meteor Showers?
A brief description of what comets are and how they are responsible for meteor showers on the Earth.
01:22
September 01, 2020
What is the Cosmic Microwave Background?
What is the Cosmic Microwave Background?
A brief description of the Cosmic Microwave Background (CMB) also known as the Primordial Background Radiation.
01:40
August 27, 2020
How Do We Classify Stars?
How Do We Classify Stars?
A brief description of how we classify stars based on their surface temperatures.
02:03
August 25, 2020
What is Meant by Hierarchical Clustering in Astronomy?
What is Meant by Hierarchical Clustering in Astronomy?
A brief description of the concept of hierarchical clustering in astronomy.
01:53
August 23, 2020
What is the Interstellar Medium?
What is the Interstellar Medium?
A brief description of the main components of the interstellar medium, which is the stuff in space between the stars.
01:44
August 22, 2020
What is Meant by Tidal Forces?
What is Meant by Tidal Forces?
A brief description of what tidal forces refer to and why they are important in astronomy.
02:09
August 21, 2020
What is Newton's Law of Universal Gravitation?
What is Newton's Law of Universal Gravitation?
A brief description of Newton's Law of Universal Gravitation and its applicability.
01:38
August 21, 2020
What is the Copernican Principle?
What is the Copernican Principle?
A brief description of the Copernican Principle.
01:14
August 21, 2020
What is Dark Energy?
What is Dark Energy?
A brief description of Dark Energy, which is causing the acceleration of the Universe.
01:10
August 18, 2020
What is Gravitational Lensing?
What is Gravitational Lensing?
A brief description of what a gravitational lens is and how it works.
01:34
August 13, 2020
How Do We Classify Galaxies?
How Do We Classify Galaxies?
A brief description of how we classify galaxies using the Hubble Tuning Fork Diagram.
01:46
August 13, 2020
What do I Need to Know About the Planet Neptune?
What do I Need to Know About the Planet Neptune?
A brief description of some interesting facts about the planet Neptune.
00:58
August 11, 2020
What do I Need to Know About the Planet Uranus?
What do I Need to Know About the Planet Uranus?
A brief description of some interesting facts about the planet Uranus.
01:02
August 11, 2020
What do I Need to Know About the Planet Saturn?
What do I Need to Know About the Planet Saturn?
A brief description of some interesting facts about the planet Saturn.
00:51
August 11, 2020
What do I Need to Know About the Planet Jupiter?
What do I Need to Know About the Planet Jupiter?
A brief description of some interesting facts about the planet Jupiter.
00:58
August 11, 2020
What do I Need to Know About the Planet Mars?
What do I Need to Know About the Planet Mars?
A brief description of some interesting facts about the planet Mars.
01:04
August 09, 2020
What do I Need to Know About the Planet Venus?
What do I Need to Know About the Planet Venus?
A brief description of some interesting facts about the planet Venus.
01:05
August 09, 2020
What do I Need to Know About the Planet Mercury?
What do I Need to Know About the Planet Mercury?
A brief description of some interesting facts about the planet Mercury.
01:02
August 09, 2020
What are the Different Types of Telescopes?
What are the Different Types of Telescopes?
A brief description of the different types of telescopes and the most important characteristic to consider when comparing them.
02:24
July 30, 2020
Why is the Sky Blue?
Why is the Sky Blue?
A brief explanation of why the sky is blue within the context of the Scientific Method as described in the episode "What is Science?"
01:41
July 29, 2020
What are Interstellar Reddening and Extinction?
What are Interstellar Reddening and Extinction?
A brief explanation of interstellar reddening and extinction and why understanding their effects is important in astronomy.
01:56
July 29, 2020
How Did the Earth's Moon Form?
How Did the Earth's Moon Form?
A very brief description of the Giant Impact Hypothesis that describes how the moon formed.
00:49
July 29, 2020
What do we Know About the Sun?
What do we Know About the Sun?
A brief description of some of the things we know about the Sun.
01:40
July 28, 2020
What is Conservation of Angular Momentum?
What is Conservation of Angular Momentum?
A brief description of angular momentum and how it is conserved in rotating systems that we encounter in astronomy.
01:50
July 28, 2020
What is the HR Diagram and the Main Sequence?
What is the HR Diagram and the Main Sequence?
A brief description of the Hertzsprung Russell (HR) Diagram and its primary feature known as the main sequence.
01:47
July 27, 2020
What is the Doppler Effect and Redshift?
What is the Doppler Effect and Redshift?
A brief description of the Doppler Effect and how it can be used to measure the motion of celestial objects toward (via blueshift) and away (via redshift) from us.
01:57
July 24, 2020
What is the Inverse Square Law of Light?
What is the Inverse Square Law of Light?
A brief description of the inverse square law of light and how we use it to determine the distances of celestial objects.
01:53
July 24, 2020
What are Newton's Laws of Motion?
What are Newton's Laws of Motion?
A brief description of Isaac Newton's three laws of motion.
01:10
July 24, 2020
Can the Millennium Falcon Really do the Kessel run in 12 parsecs?
Can the Millennium Falcon Really do the Kessel run in 12 parsecs?
A basic definition of the distance unit we call a Parsec.
02:17
July 23, 2020
Does Science Prove Things?
Does Science Prove Things?
A brief description of how science does not prove things but rather provides evidence in favor of or against a particular theory.
01:16
July 23, 2020
How do we know there is a black hole at the center of our galaxy?
How do we know there is a black hole at the center of our galaxy?
A description of the main piece of evidence supporting the hypothesis that there is a black hole at the center of our galaxy.
01:43
July 23, 2020
What are Kepler's Laws?
What are Kepler's Laws?
A brief description of Kepler's Three Laws of Planetary Motion.
01:37
July 23, 2020
What are Active Galaxies?
What are Active Galaxies?
A basic description of an active galaxy and how it produces the energy that we observe from it.
01:22
July 22, 2020
How Did the Solar System Form?
How Did the Solar System Form?
A brief description of the Nebular Hypothesis which is believed to describe how the Solar System formed.
02:00
July 21, 2020
Why Did I Create These Podcasts?
Why Did I Create These Podcasts?
A brief explanation of why I felt the need to create another podcast about astronomy.
01:14
July 21, 2020
Will Polaris Always be the North Star?
Will Polaris Always be the North Star?
A description of Precession of the Equinoxes which determines what the north star will be.
02:05
July 19, 2020
What Happened to Pluto Formerly Known as a Planet?
What Happened to Pluto Formerly Known as a Planet?
A description of one of the main reasons why Pluto is no longer classified as a planet.
01:59
July 19, 2020
How Do We Name Stars?
How Do We Name Stars?
A brief description of how astronomers refer to individual stars in the sky.
01:34
July 17, 2020
What is a Constellation?
What is a Constellation?
A brief description of what the ancients and modern astronomers call constellations.
01:17
July 17, 2020
What are Variable Stars?
What are Variable Stars?
A brief description of the two very broad categories into which variable stars are classified.
01:14
July 17, 2020
What is Helioseismology?
What is Helioseismology?
A description of what helioseismology is and how we can use it to determine the various properties of the Sun.
01:35
July 15, 2020
What do Astronomers do?
What do Astronomers do?
A brief explanation of what professional astronomers actually do in their role of applying the scientific method to better understanding the Universe.
01:41
July 14, 2020
What is the Difference Between Astronomy and Astrophysics?
What is the Difference Between Astronomy and Astrophysics?
What is the Difference Between Astronomy and Astrophysics? In a word, nothing!
00:48
July 14, 2020
How do we use Light to Study the Universe?
How do we use Light to Study the Universe?
A brief description of the ways in which we analyze light to help us better understand the Universe.
01:40
July 14, 2020
What is the Solar System?
What is the Solar System?
A description of the basic constituents of the Solar System. 
02:11
July 14, 2020
What is Cosmology?
What is Cosmology?
A basic description of what cosmology is and the assumption we need to make in order to apply it to the universe.
01:34
July 14, 2020
What is Light?
What is Light?
A basic explanation of our theory for how light, a.k.a. electromagnetic radiation, behaves.
01:50
July 12, 2020
What is the Big Bang?
What is the Big Bang?
A brief description of the Big Bang Theory and one of its primary predictions.
01:46
July 12, 2020
What is Dark Matter?
What is Dark Matter?
A brief description of how we know dark matter exists.
01:49
July 10, 2020
What are M-numbers and NGC-numbers?
What are M-numbers and NGC-numbers?
An explanation of what M-numbers and NGC-numbers mean and represent in astronomy.
02:12
July 10, 2020
What is a Galaxy?
What is a Galaxy?
A brief description of a galaxy and a cluster of galaxies.
01:16
July 10, 2020
What is a Nebula?
What is a Nebula?
A brief description of the 4 types of nebula we have identified in astronomy.
02:06
July 10, 2020
What is a Star Cluster?
What is a Star Cluster?
A description of the different kinds of star clusters and their properties.
02:03
July 10, 2020
How do Stars Form?
How do Stars Form?
A brief description of the process by which "A Star is Born."
01:50
July 10, 2020
Where do the Chemical Elements Come From?
Where do the Chemical Elements Come From?
A brief description of the origin of the chemical elements seen in the periodic table.
01:49
July 10, 2020
What is a Brown Dwarf?
What is a Brown Dwarf?
A brief description of what a brown dwarf is and how it's formed.
01:47
July 09, 2020
What is Science?
What is Science?
A brief description of what science is and how it works.
01:57
July 09, 2020
How do we measure distances in Astronomy?
How do we measure distances in Astronomy?
A very brief description of how we measure distances of celestial objects. This is truly a 30,000 foot view of a very complicated subject. 
01:28
July 09, 2020
What is a Quasar?
What is a Quasar?
A brief description of what a quasar is and what we think they represent.
01:40
July 09, 2020
Astronomy is a Science of Extremes
Astronomy is a Science of Extremes
This episode explains how astronomy is a science of extremes.
01:44
July 08, 2020
What is the Celestial Sphere?
What is the Celestial Sphere?
A brief description of the celestial sphere and how astronomers precisely locate objects in the sky.
02:00
July 07, 2020
What is a Black Hole?
What is a Black Hole?
A brief description of the basic property of a black hole.
01:22
July 06, 2020
What is a Pulsar?
What is a Pulsar?
A brief description of the basic definition and properties of a pulsar.
01:26
July 06, 2020
How do Stars Die?
How do Stars Die?
A brief description of what happens to stars when they reach the end of their lives.
01:34
July 03, 2020
How do Stars Evolve?
How do Stars Evolve?
A description of how stars live their lives and evolve with a little about how they end their lives.
01:26
July 03, 2020
What is a Supernova?
What is a Supernova?
A brief description of a supernova.
01:14
July 03, 2020
What is a Nova?
What is a Nova?
A concise description of novae and what causes them to occur.
01:29
July 03, 2020
What is Astronomical Vocabulary?
What is Astronomical Vocabulary?
A description of how astronomers use everyday language to refer to the objects they are studying.
02:14
July 03, 2020