HomeStar – 21st Century Home Planetarium

Featured on Slashdot on June 12th, 2006, under Toys, Space, and Science.


Pat once told me that he harbours an inexplicable compulsion to be in space. His belief is that when he’s finally there, he’ll have all the answers. Life. God. 42. The metaphysical implications don’t make sense, yet this is what he truly thinks. It’s a strange hole in the logical being I know as Pat, and only the enigmatic curiosity of the night sky can do this to someone.

I’m no exception. Something borne in us from childhood is a fascination that stems from the unknown. The stars provide enough for us to wonder about for a lifetime.

Unfortunately, for those who live in the city, there’s little chance to see the sky without “sky glow”, the annoying phenomenon that drowns out a large number of stars visible to the naked eye and telescope alike. As a by-product of industrialization, light pollution has taken the sparkle out of the stars, and this is where the HomeStar comes in.

What Is A HomeStar?

Thumbnail: Hoodie view

According to the official Homestar website, (translated through Babelfish):
“It is the planetarium for worldwide first optical type home. It is possible to exceed several thousand numbers of stars that to project approximately ten thousand thing stars it can see generally with naked eye of the human.”

According to me, the Sega Toys HomeStar is a home planetarium. It turns any room into an astronomical theatre, by projecting up to 10,000 stars onto a wall or ceiling.

Alternatives to the HomeStar until now have been rather crude. has a list of Top Toy Planetariums, and most of them aren’t above $40 USD, giving kids a few fuzzy points of light on a nearby wall. There’s also the StarDome, which offers a better image, at the cost of a much more significant investment. This includes a week of construction, electrical work, as well as a steeper price.

The HomeStar is mid-ranged geek toy. It’s provides an extremely detailed star field, while remaining portable and affordable ($239.00 USD as of June 2006).


  • Weight: 1 kg
  • External size: W16.7 x H15.9 x D15.1 cm
  • Power source rating: Input — AC100V, 50/60Hz / Output – DC5V, 1.2A
  • Electric power consumption: 3w
  • Electric battery life: 6 hours
  • Power source: Private AC adapter / private electric battery box

The HomeStar also comes with three features. There’s a random shooting star generator, which projects an ephemeral comet that flies through the stars. A sleep timer allows the unit to turn off automatically after a set amount of time. The projection can also rotate, to simulate the rotation of the earth.

Package Contents

Thumbnail: Box front

Thumbnail: Box back

Thumbnail: Package contents

I ordered my Homestar from Audiocubes, a sort of middle-man to Japan. The order was placed on a Thursday, shipped on Sunday, and arrived on Tuesday. Not bad.

The Homestar comes in a stylish box, with pictures of the night sky on the side.

In the box

  • HomeStar
  • Two northern sky discs (with and without constellations)
  • AC Adapter
  • Explanation Handbook
  • Explanation CD
  • Battery Box

Thumbnail: Homestar instructions

Unfortunately, all documentation, as well as the explanation CD, are in Japanese. As simple as it is to use the HomeStar, there are some rather intimidating images in the manual that make me feel like there’s something I should know.

One can also purchase two southern sky discs, but at an extra $80 USD, I didn’t think it was worth the price. I don’t think they can be shipped separately, so the decision should be made before ordering.

Design And Construction

Thumbnail: Starball front

Thumbnail: Starball back

The HomeStar usually comes in two colours, silver and black, although limited editions have special gradient and pastel colours. It comes in a matte finish, while the well-designed silver base adds a nice contrast. Soothing curves give it a modern look. It’s stylish enough that it can be stored almost anywhere out in the open without looking out-of-place. I chose the black so that it wouldn’t stand out in the room, although this also means that it’s harder to see in the dark, making it potentially easier to break.

The unit is much lighter than expected, but not to the point where it feels flimsy. I imagine that inside is simply a lens used to focus the stars, a motor to rotate the discs, and a light source.
Shaking the sphere doesn’t cause any rattling.

Buttons are solid, with good tactile feedback. The focus ring is much too loose for my preference, although this may be good because it can take quite a lot of turning to get the stars to the right sharpness. I also have a difficult time remembering which direction to turn the know for closer or further focus, as there’s no visual markings on the unit itself. I bet there are Kanji characters for clockwise and counter-clockwise somewhere in the manual.

Thumbnail: North hemisphere disc

Thumbnail: North constellations disc

Thumbnail: Disc close-up

The image discs are much more solid than they look in the pictures. They’re about 3mm thick, made of sturdy plastic that doesn’t bend. The thing to be most careful of is getting the surface of the disc scratched. Although this wouldn’t actually ruin the thin black layer of stars sandwhiched between the plastic, may it may still alter the image.

Using The HomeStar

Thumbnail: Ceiling projection

Thumbnail: Starball back open

Stucco ceilings are not a problem; the starfield shows up crisp and clear on mine. The HomeStar should be placed in the middle of the room. If it’s too much to one side, the depth of field is too narrow to contain both sides of the field, resulting in a stretch. Unfortunately, this isn’t always easy or convenient. The effect can be seen in the picture on the left. However, it does come with a battery box that allows for more portability. This is supposed to last up to six hours, but the AC cable is long enough that I haven’t had to use this yet.

The projected image doesn’t include the entire sky, just a portion of the disc. This makes the rotation feature much more valuable, as it cycles through the sky once every six minutes. It’s a very subtle effect. Often, I’ll have to ask a second opinion whether the stars are actually moving. The image can be slightly dizzing; I’m reminded of the morning of a hangover, when the entire room seems to spin.

Thumbnail: Colour coded lights

There’s very little light leakage from the HomeStar, and this is a very important feature. The mode LEDs are rather dim, and the projection lens is recessed inside the unit enough that you can’t easily blinded if you happen to walk by the unit. Any stray light will wash out the stars; light pollution exists inside the house now, with superbright LEDs on many electronic units. I find myself covering up the LEDs from my bluetooth charger and speaker panel when using it.

The shooting star generator is a little disappointing. The small comet comes at a set interval, and at the same location every time. Not quite the mystical, random effect that I was hoping for.

For those with glasses, the use of the HomeStar becomes a little more limited. After taking your glasses off to go to bed, the starry ceiling becomes somewhat of a blur, depending on the strength of your prescription. There’s still a sparkle in the eyes, but it’s not the same effect of sleeping under the stars that you pay for.


The HomeStar very effectively simulates a clear, starry night. With a darkened room, the effect becomes quite romantic. It can’t match the actual night sky while camping or out in cottage country, but for people who live in densely populated areas, it does the job well. Makes a great gift, especially for people who have everything, and kids with space-themed rooms. Astronomy (and eventually astrophotography) is something I hope to afford some day, but until then, the HomeStar will give me the enough of the heavens that I need. A highly recommended item, if price isn’t a problem.


  1. The Homestar Earth Theater is not worth the money, the pico projector is JUNK and the image projection is worse than awful. It is nothing more than a Homestar Pro (which isn’t worth the money either) with a very, very cheap pico projector-save your money!

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