Steve’s Virtual Planet

How stars shine

One of my previous posts considered the use of the terms magnitude and size when talking about a star. Well, as I pointed out then, when we are talking about stars, one has to start with the term “mass”. Everything depends on the stellar mass. That is the starting point when trying to understand all of the other physical properties of any star. The star’s initial mass sets the course for the life of that star and even its life span.

These links get you to the heart of a star quite literally to detail a star’s radiation and stellar structure. Star’s shine because of the enormous amounts of energy released in their cores due to nuclear fusion. The star’s mass, in combination with the force of gravity and the electromagnetic and nuclear forces, provides the means for a star to brightly shine for millions and even billions of years.

Without duplicating all that is written already about stars, the additional links below take you to more of the Wikipedia pages on stars and their complex characteristics.

Wikipedia: Star

Wikipedia: Stellar_evolution

Wikipedia: Star_formation

Wikipedia: Stellar_structure

Wikipedia: Stellar classification

Originally published 5-10-15, revised 6-26-25

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Full Moon Names - April

The most common traditional full moon name for April is the Pink Moon. One might think of spring time and the robins looking for worms, but check the alternate names in the links below,

This year, the full Moon appears on Saturday, April 12th. In the eastern US, the moon will rise at 8:22 PM and should start clearing the tree line around 9:45 PM.

From the older Old Farmer’s Almanac - April Full Moon. See the article to access a moon rise calculator. There are also alternative names from early American history various native cultures.

From the newer Farmer’s Almanac - April Full Moon. There is a deeper explanation of the history of the worm moon in North America and some additional alternate names.

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Orion, The Hunter - Part One

For this first installment of “The Constellations” series, I am going take the opportunity to begin with perhaps my favorite of them all, Orion.

Orion is one of most recognizable star patterns in the sky and is often depicted as a male human figure, for example, The Hunter. The Greek mythology concerning Orion is the one most well known in modern time, however, peoples all over the world have invented all manner of stories about this prominent constellation. For at least 50 centuries cultures have been known to idolize this god like character in their myths and legends.

As fascinating as these eons of myths are, the stars, clusters and deep sky objects within Orion are truly the highlight of this wonderful constellation. Many of these features are easy to locate and study through a modest size telescope. Even in a suburban sky, one can see 8 stars bright enough to peep through the typical sky pollution of a big city. Some objects are even more impressive through binoculars for a wider field of view. The Orion Nebula, for example, is the main feature that reveals more and more detail as you view with increasing magnification.

The most well known and studied objects in Orion are between about 240 to around 1500 light years from Earth, part of the Milky Way. These primary targets that we see in the constellation reside in the same spiral arm of the galaxy, which is where our own Solar System is found. This concentration of stars is known as the Orion-Cygnus Arm. At this relatively close distance, Orion’s stars and nebula are truly in our cosmic neighborhood.

Check out the links above as there is a wealth of information and history related to Orion. Look for more additions on Orion as part of the series “The Constellations”. I will be exploring the key objects already mentioned and describing binocular and telescope views for suburban and country skies.

Originally published on 2-24-24, updated 3-20-25

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Full Moon Names - March

The most common traditional full moon name for March is the Worm Moon. This year we also get a “Blood” Moon as a bonus, a full lunar eclipse visible from all of North America!

This year, the full Moon appears EARLY on Friday, March 14th. In the eastern US, the moon will rise at 8:19 PM EDT however the lunar eclipse begins around 11:57 PM EDT.

One might think of spring time and the robins looking for worms, but check the alternate names in the links below.

From the older Old Farmer’s Almanac - March Full Moon. See the article to access a moon rise calculator. There are also alternative names from early American history various native cultures.

From the newer Farmer’s Almanac - March Full Moon. There is a deeper explanation of the history of the worm moon in North America and some additional alternate names.

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Full Moon Names - February

This year, the full Moon appears on Wednesday, February 12. In the eastern US, the moon will rise at 11:43AM.

The most common traditional name for this month is the Snow Moon.

From the older Old Farmer’s Almanac - February Full Moon. See the article to access a moonrise calculator. There are also alternative names from other cultures.

From the newer Farmer’s Almanac - February Full Moon. There is an expanded explanation of the history of the wolf in North America and some additional alternate names.

Originally published 2-24-24; updated 2-12-25

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Full Moon Names - January

This year, the full Moon appears on Monday, January 13. In the eastern US, the moon will rise at 5:27PM.

The most common traditional name for this month is the Wolf Moon.

From the older Old Farmer’s Almanac - January Full Moon. See the article to access a moonrise calculator. There are also alternative names from other cultures.

From the newer Farmer’s Almanac - January Full Moon. There is an expanded explanation of the history of the wolf in North America and some additional alternate names.

Originally published 1-17-24

Updated 1-12-25

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The Great Mars coverup!

Yes, that’s right, Mars is going to disappear!! Well, I am teasing a bit, of course - The Red Planet is actually going to be hidden by Earth’s Moon a short time in a phenomenon known as an occultation. This happens when one celestial object blocks the view of another. Our Moon does this quite regularly and the events are quite predictable. The other object can be a planet, but is more frequently a well know star or cluster.

The event will be visible over most of North America on Monday, January 13. The event takes place from around 9:00PM to 10:30PM EST, if you’re in the US Eastern Time zone. See the AL document below for times over the rest of the US.

I first caught the news about this from SpaceWeather.com on their January 9 posting. The clever people over at In-The-Sky.org have a great blog on this event with lots of details and timings. Plus, the Astronomical League (AL) has produced a single page PDF work sheet you can download. You can check out these resources and get situated for the event and view it naked eye or through binoculars. Even if its a chilly night, it will only take 10-15 minutes to watch the start, then duck in side for a hot drink before seeing Mars reappear about an hour later. Gook luck!

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Winter Solstice 2024

Ok, I’ll be brief … it’s not just another short day today, but at 4:20 AM EST, it was officially the Winter Solstice for December 2024. That interesting fact is obviously very important to a great many people around the world!! Now, this year on the morning of, admittedly I was not up and wide awake at this hour of celebration. Nevertheless, judging by the accounts in the news later in the day(light), there were numerous gatherings at places like Stonehenge, which is perhaps the most famous site for this event.

However, the druids of Britain aren’t the only revelers out making the most of the shortest day in the year. Cultures from as far back as the New Stone Age have recognized the significance of the solstice. From those times, holidays have been created by numerous groups worldwide to celebrated it. You can start closer to home with some background on this event with a more practical and scientific perspective by checking these articles in the two popular almanacs.

The Old Farmers Almanac has a very nice explanation of the Winter Solstice from an astronomical viewpoint. There is also a deeper explanation of what the seasons are about and how they are celebrated around the world. The other publication, called simply The Farmer’s Almanac, has an article from a cultural perspective and outlines a number of different festivals associated with the Winter Solstice.

I wrote about some of the world wide celebrations in an earlier post.

originally posted on Dec 21, 2024

updated on Dec 22, 2024

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Jupiter Opposition - 2024

The planet Jupiter is putting on a great show all night for the month of December. It will be closest to Earth on Dec 6 and reach opposition the next day.

The web site EarthSky is a great place to go for all kinds of insights into our solar system as well as articles on space and astrophysics. Check out their Astronomy Essentials section for a fine article on this year’s opposition with sky charts and lots of details about our largest planet.

originally published Dec 6, 2024

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Full Moon Names - December

The traditional full moon name for December is the Full Cold Moon (also called the Long Night Moon). This month’s full moon will reach its peak on Sunday, December 15th, at 4:02 AM EST.

The name of this month’s full moon is used by the Celts and various indigenous cultures in North America especially with the onset of Winter and the shortest daytime on the Winter Solstice. See even more details of these cultural references in the links below.

From the older Old Farmer’s Almanac - December Full Moon. See the article to access a moon rise calculator. There are also alternative names from early American history various native cultures.

From the newer Farmer’s Almanac - December Full Moon. There is a deeper explanation of the history of the full moon names in North America and some additional alternate names.

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