The Star Nearest Earth — Alpha Centauri has a Planet

The Star Nearest Earth: night sky view of Alpha, Beta and Proxima Centauri

A photograph of the night sky showing Alpha Centauri A&B (top left), Beta Centauri (mid-right), and Proxima Centauri (within red circle). Photo: Skatebiker (CC BY-SA 3.0), via

The star nearest Earth? Alpha Centauri? I can hear it now. Someone is getting “literal” on me and declaring that the star “nearest” Earth is our own sun. Okay, they’re right, but only in one sense. Our sun is literally a star, certainly. But in the vernacular, “star” usually refers to those tiny points of light in the night sky—not the daytime. So, even though the star nearest to the Earth is our sun, literally, it is not so in the everyday sense of common language.

Other purists will likely complain that Proxima Centauri is closer than “Alpha Centauri.” They would also be right, but only in a sense. Proxima is not a star that we can see in the night sky. Okay, I’m quibbling. But Proxima is also a part of the Alpha Centauri system. So, you see, in one sense Alpha Centauri really is the star nearest Earth. And it’s actually 3 stars.

The Star Nearest Earth: artist rendition of new Alpha Centauri planet

Artist’s rendition of the Alpha Centauri system with the newly discovered planet. In the background is our own sun as a bright star in their night sky. Image: ESO, L. Calçada, N. Risinger (CC BY 3.0), via

The star nearest Earth now has a known planet

The Star Nearest Earth: photo of Alpha Centauri

Photograph of Alpha Centauri with more distant stars of the Milky Way in the background. The one glaring dot holds both Alpha Centauri A and Alpha Centauri B. Photo: ESO (CC BY 3.0), via

October 17, 2012, NASA announced the discovery of a planet orbiting Alpha Centauri B, the second brightest star in the trinary (ternary or 3-component) system. In that announcement, they congratulated the European Southern Observatory (ESO) team (Xavier Dumusque, et al) for their discovery.

That world is far too near to its sun to allow life as we know it, but the mass of that world is close to that of our own home planet. We don’t know the exact mass, because we don’t know the tilt of the planet’s orbit. But the minimum mass is approximately 1.13 ± 0.09 times the mass of Earth. If the orbit is perfectly edge-on, then this minimum mass would be the actual mass. The greater the orbital tilt, the greater the actual mass.

The Star Nearest Earth: Earth from above Pacific Ocean

The dream of finding an Earth-like world orbiting the star nearest Earth is a strong one. Will it look like this? Earth above the Pacific Ocean. Photo: NASA.

But the orbital period of this world is a brisk 3.24 days. That means that its year is less than half of our week. This also means that the planet is so close to its sun that it likely remains scorched on one side and frozen on the other. It is doubtful that it even has an atmosphere. The intense heat of being so close to its sun surely has stripped the world of any but the thinnest veil of gas.

And yet, if the mass is considerably more than that of Earth (high orbital tilt), then the planet might retain an atmosphere by the shear brute force of gravity. But the heat would still be unbearable. That heat would likely be transferred by winds all around the world, in a way much like that on Venus.

The prospect of finding other worlds in this nearest star to Earth

The Star Nearest Earth: will it have a world with jungles and mountains?

Jungles and mountains. Will our first Earth-like world have these? Photo: Micky07, licensed through (62860).

Each of the 3 stars of Alpha Centauri might have planets. What interests us most are the brighter two. Proxima is little more than a hot planet itself, with violent flares from time-to-time.

Could an Earth-like world exist in the habitable zone. Could such a world remain unperturbed by the elliptical orbits of Alpha Centauri A and B about one another? The prospect is exciting. To find a world just like Earth in the star system next door is a dream come true for those of us who have had many dreams of such things. What would that world be like? Would it have jungles like our own world? Would it be completely desert? Or would it contain only oceans and perhaps a few islands?

Traveling to the star nearest Earth has long been a passion of mine. To see the worlds of that ancient star system would be like waking up at Christmas with lots of presents. And Alpha Centauri is indeed ancient—at least a billion years older than our star system. If it developed life and civilization on a timetable similar to that in our own system, its civilization would’ve been a billion years old when ours just started.

The star nearest Earth in 3D

The image, below, is from the “Stars in the NeighborHood” software.

The Star Nearest Earth: showing in software the location of Alpha Centauri

Screen shot of “Stars in the NeighborHood” software, showing the location of Alpha Centauri, on the left. The blue “Viewing Cube” (left) is represented as the blue wireframe within the “Locator Cube” (right). (Not full size)

The Viewing Cube on the left shows Alpha Centauri selected with the green “focus” marker. Just above the Alpha Centauri system, the similar yellow dot represents our own sun. The distance between them is a mere 1.33 parsecs (4.33 light years).

The Star Nearest Earth: Alpha Centauri in "Stars in the Hood" sky view

This “Stars in the Hood” sky view shows alternately the natural view and distance view. Here, Beta Centauri has the green “focus” marker.
(Not full size)

On the right in the screen shot above, the Locator Cube shows the blue Viewing Cube’s location within our galactic vicinity. The yellow dot within marks the position of our sun.

To the right, this second screen shot (from “Stars in the Hood” software) shows alternately the night sky looking toward Alpha and Beta Centauri and the “Distance View” of the same portion of sky.

Here, the more distant, Beta Centauri is selected with the green “focus” marker. Alpha Centauri is just to the left. In the “Distance View,” the size of the stars is an indication of how far away they are.

As you can see, the star nearest Earth, Alpha Centauri, is very large (close) while Beta Centauri is very small (distant). This is despite the fact that they appear to have very similar brightness in our night sky.

Below, the software image shows the location of Beta Centauri. This is nowhere near our own Solar neighborhood. This brings into sharp contrast the closeness of Alpha Centauri—the star nearest Earth.

In all of our gargantuan galaxy, the relatively tiny distance to Alpha Centauri seems small indeed. It’s somewhat comforting to know that there are planets next door.

For more details, check out the Alpha Centauri Stellar Closeup.

What if we someday find a planet like our own in our next-door neighbor system? What are your thoughts on finding an Earth-like planet so close?

The Star Nearest Earth: software focus on Beta Centauri

This software view of Beta Centauri shows that, even though Alpha and Beta are near each other in the sky, and nearly the same brightness, they are separated by a great distance. The blue wireframe cube on the right is centered on the location of Beta Centauri, far from our sun.
(Not full size)

Closest Planets and Guide to Our Corner of the Galaxy

Like the closest planets, this island of the Caribbean sits amongst many neighbors (Grenada Island, West Indies)

Like the closest planets, this island of the Caribbean sits amongst many neighbors. Grenada Island, West Indies (Caribbean). Photo by Varun Kapoor (CC BY 3.0), via

I’ve long had a fantasy of hopping the closest planets, like pirates hopped the islands of the Caribbean centuries ago. That dream started more than a year before Sputnik.

Nearly ten years ago, I wrote 3D astronomy space software, Stars in the NeighborHood. Back then, it was merely a passion, and that’s not a bad thing. The idea was to see if there were any tight clusters of stars with nearby planets making such world hopping easy.

This article is a “biased” review of this software. Why biased? Simple. I wrote the software (programmed it, wrote the text and help files, and did the artwork).

Since moving overseas, I’ve had more time to promote the software and sales are picking up. Maybe I’ll never get rich with the software sales, but sharing these stunning views of our universe is a reward all by itself. Not only does the software show the location of the closest planets in other star systems, it shows what the night skies look like from those alien worlds.

I’ve added YouTube videos to my space software website, to help visitors get a better idea what the software is like in action. And I guess it’s the science geek in me—or perhaps the adventurer—but I still get a kick out of exploring our neck of the galactic woods with Stars in the Hood. A simple click and drag of the mouse turns countless trillions of cubic miles of space, letting you see our neighborhood of stars in colorful 3D.

The Closest Planets and Stars

Looking at our night sky, it’s hard for some to get the sense of depth of space. With Stars in the NeighborHood, you can open up the “sky view map,” click on a star, and in the “viewing cube,” see which stars are really close to the one you’ve selected out of our night sky. But that’s not all. Right in the “sky map closeup,” you can select the “distance” viewing mode and instantly all of the stars are varying sizes representing distance instead of brightness.

Closest stars are larger in Distance Viewing Mode

Closest stars are larger in the Distance Viewing Mode. The large red star is Proxima Centauri as seen from Alpha Centauri. The largest, pale green star is Sirius. Behind Sirius, the tiny (distant) stars make up the constellation of Orion.

This “distance viewing mode” allows you to tell at a glance which stars are close and which are far away. Why is this an issue? Without such a tool, you can’t tell which stars are close and which are far away, because individual stars are not all the same brightness. The closest star, Proxima Centauri, is too dim to see without a powerful telescope. Rigel (Beta Orionis), on the other hand, is one of the brighter stars in our night sky, but it stands an estimated 870 light years away. In fact, Rigel can be seen throughout most of this half of the galaxy.

The “Star” of the Movie

Click another checkbox, “Show Alien Skies,” and the “sky map” shows not our own night sky views, but those of the star you’ve selected. Looking at those alien skies gives me the thrill of actually being there—having traveled through space to a new star system. Even for nearby Alpha Centauri (our next-door neighbor, and “star” of the James Cameron movie, Avatar), there are interesting differences in otherwise familiar constellations.

Alien Sky View: what it might look like from one of the closest planets in the Proxima Centauri system.

Alien Sky View: what it might look like from one of the closest planets in the Proxima Centauri system, looking at nearby Alpha Centauri (Sky Map Closeup, on the right). The orange star below is first magnitude, Antares. The Viewing Cube (left) shows Proxima Centauri (with green focus marker), nearby Alpha Centauri, and our Solar system far above.

Below our own sun in the “viewing cube,” the brighter star, Delta Pavonis, is famous in the fictional realm of Frank Herbert’s award-winning work, Dune—the sun of planet Caladan, long held by the family Atriedes. In the galactic “locator cube,” you can see that the sun of Arrakis, Canopus, is just outside the Solar neighborhood. With the XYZ controls, you can scroll down and over to it to get a closer look in the “viewing cube.”

Many Ways to View Our Galactic Neighborhood

For any interesting stars you find, you can add a color tag, visible in the “viewing cube,” and you can even add notes on your thoughts and observations.

The galactic “locator cube” also helps you home in on some of the nearby star clusters like, Ursa Major (the “Big Dipper”), the Hyades and the Pleiades (in Taurus), the Coma (Coma Berenices), and the Praesepe or “Beehive” (in Cancer and “twin” to the Hyades).

Closest planets outside the Solar system as shown in Stars in the Hood software

Closest planets outside the Solar system as shown in Stars in the Hood software. In the Viewing Cube (left), the red ellipses indicate stars with known planets near Earth. The green focus marker shows the location of our sun and Earth. The Locator Cube (right) shows the location and size of the Viewing Cube within our galactic vicinity.

Perhaps my favorite part of the software is the “Zoom Out Universe” feature. This allows you to zoom out from Earth all the way to the scale of the local group of galaxies. Go to zoom level 3 (the 1,000 parsec scale), and you see how the Solar neighborhood “viewing cube” and galactic vicinity “locator cube” relate to the disk of the Milky Way galaxy (our home city of stars). Be sure and turn on the “Increase Visibility” checkbox to get a clearer view of all those stars! Some of the more famous stars, like Rigel, Betelgeuse, Antares and Polaris, are outside the Solar vicinity, and this lets you see just where they are in 3D space.

There’s a free gift that comes with the software that helps you understand what you’re looking at. This “Space Poster Guidebook” not only gives you labeled views of the software, but full-color space art of alien worlds.

If you have a chance to stop by www.SpaceSoftware.Net, let me know what you think. And if you happen to purchase the software, I’d like to know what you think of that, too. User comments have helped to make the software better and better.

What are your dreams about space? What excites you when you look up at the night sky?

“Closest Planets” Originally published as “Guide to Our Corner of the Galaxy,” 2010:0405–19:27:43 at

Space the Final Frontier — Rebirth of a Blog

Space the Final Frontier: Real space shuttle Enterprise with TV crew of fictional Starship Enterprise

Space the Final Frontier: Real space shuttle Enterprise with TV crew of the fictional Starship Enterprise. Photo courtesy NASA (PD), via

When I first heard the words, “space the final frontier,” I felt right at home. For the last 58 years, I’ve been contemplating the stars and their planets. I dreamed of being an astronaut before Sputnik. Yes, I was even a Star Trek junkie during the original series on television.

As an artist, I painted what I called “spacescapes.” These once illustrated the halls of Griffith Observatory in Los Angeles. I’ve even held one-person art shows at places like the Bonaventure, downtown. My art even graced the silver screen. This allowed me to work with a number of celebrities. This included two-time Academy Award winning designer, Saul Bass.  I also worked with world renowned writer, Ray Bradbury, and Star Wars special effects wizard, George Mather.

I went on to write my own 3D astronomy space software, “Stars in the NeighborHood.” As a writer, I co-authored with John Dalmas, Touch the Stars: Emergence, published by Tor Books, New York. Recently, I expanded and republished, available as a Kindle e-book on Amazon.

I had lived and breathed “space the final frontier” in my art, my software creations and in my writing.

New Direction for the Blog Based on “Space the Final Frontier”

When I originally created this blog, I opened it up for anything in the universe. I wrote a dozen articles and then moved the blog to a new web host. Something broke in the move and I never got around to fixing it.

But now, I’ve decided to dedicate this blog to space: astronomy, planets, space travel, science and related topics. This blog will now emphasize “space the final frontier.”

All other subjects are being moved to other blogs. If you’ve read any of the older articles here, you will soon be able to find them in their respective new homes:

In the meantime, I will be carving out a new niche, here. The focus will be on stars, planets and all that fun stuff out there—space the final frontier.

As always, I’m open to suggestions. What would you like to talk about?