PleiadAtlas for Palm OS: A Deep Star Atlas for Palm Handhelds

During the Palm OS era, a small community of amateur astronomers carried star charts not on paper but on a Palm handheld clipped to a belt or tucked into a jacket pocket. One of the deepest of these charts was PleiadAtlas, a star atlas built by amateur astronomer and software developer Brian Tung specifically for finding faint telescope and binocular targets in the field — a task very different from simply showing what the naked eye sees. PalmGear, the largest Palm OS software catalog of the era, listed the program under product ID 14063. This page restores what can be documented about PleiadAtlas from surviving contemporary sources, the developer's own site, and later observer testimony, and is explicit about what could and could not be verified.

PleiadAtlas has not been actively developed for many years and is not currently maintained. This article is a historical record, not an endorsement of present-day compatibility or support.

What Was PleiadAtlas?

PleiadAtlas was a computerized star atlas for Palm OS PDAs, built around a specific job: helping an observer at the eyepiece navigate from a bright, easy-to-find star to a faint deep-sky target by "star hopping" through intermediate stars, without a computerized (go-to) telescope. A December 2002 review of Palm astronomy software, written by Don Shedrick for the Dallas Astronomical Society newsletter, put the distinction plainly: "Many other programs show you the night sky as it appears to the unaided eye, but Brian Tung's PleiadAtlas puts its emphasis on showing you enough stars to lead you to your telescopic or binocular target."

That is the core distinction this article returns to repeatedly: a visual planetarium program tries to match what your eyes see when you look up, so it deliberately limits itself to naked-eye stars (roughly magnitude 6) plus solar-system bodies and event timing (rise/set, twilight, moon phase). A star-hopping atlas like PleiadAtlas instead tries to match what your telescope or binoculars see in the eyepiece field, which requires plotting far more stars than the eye alone could ever register — tens of thousands at minimum, hundreds of thousands in PleiadAtlas's deeper databases. Neither approach is strictly "better"; they answer different questions in the field.

From PalmAtlas to PleiadAtlas: Origins and Developer

PleiadAtlas was developed by Brian Tung, an amateur astronomer whose site, "The Astronomy Corner," also hosted stellar-stereogram and other Palm astronomy tools. The program's history predates the PleiadAtlas name: it began life as PalmAtlas. Brian Tung's own installer documentation instructs users upgrading from an older release to "erase" any earlier copy, explicitly noting: "If you have an earlier version of PleiadAtlas or PalmAtlas (the original name of PleiadAtlas), you should erase that program" to avoid database conflicts. A separate third-party Palm software listing independently corroborates the rename, describing the program simply as "PleiadAtlas (formerly PalmAtlas)."

The earliest dated reference found for the project is an updates log on Tung's site recording: "27 October 2000: Unveiled the new PalmAtlas Home Page, introducing v0.1 of this (currently) freeware star atlas for the Palm Pilot and compatible devices." This documents PalmAtlas as freeware at v0.1 in October 2000. The exact date of the rename to PleiadAtlas, and the exact date it moved from freeware to registered shareware, could not be confirmed from the sources available for this article.

The software's original home was hosted at astro.isi.edu/pleiadatlas/. This exact URL is independently confirmed by Brian Tung himself in an October 23, 2001 Usenet post to the newsgroup sci.astro.amateur, where he cites "The PleiadAtlas Home Page at http://astro.isi.edu/pleiadatlas/" as an astronomy resource. Archived snapshots of that original ISI-hosted page were not accessible in the research done for this article, so this piece relies instead on Brian Tung's later, self-hosted mirror at astronomycorner.net/PleiadAtlas/, which presents itself as the continuation of the same project and links to the same v2.2.1 installer and PDF manual.

Note: Because the original astro.isi.edu pages could not be directly retrieved for this article, version and specification claims below are dated to their source: the December 2002 contemporary review (Shedrick), or the astronomycorner.net mirror as it existed at its documented "last updated 21 September 2004" state. Where the two eras disagree on numbers, both are shown rather than merged.

Star Hopping, Explained

Star hopping is a manual telescope-aiming technique: rather than relying on setting circles or a computerized mount, an observer starts at a bright, easily identified star, then moves the telescope in small, deliberate steps through a chain of progressively fainter stars whose spacing and pattern are visible in both the eyepiece and the chart, until the target — a galaxy, nebula, or cluster too faint to see unaided — drifts into the field of view. The technique depends entirely on the chart showing enough faint stars to match what the eyepiece actually reveals; a chart limited to naked-eye stars runs out of usable "stepping stones" long before reaching most deep-sky targets. This is precisely the gap PleiadAtlas was built to fill, per the 2002 Shedrick review: its default 25,000-star catalog to magnitude 7.5, and optional field-star database to magnitude 9.5, were described as "plenty enough to do accurate star hopping to find those deep sky objects."

Star Catalogs and Magnitude Limits by Version

PleiadAtlas's star catalog specifications changed substantially between 2002 and 2004, and later discussion online sometimes cites the deeper, later figures without noting the version. The table below documents both eras separately, by source and date, rather than blending them.

In other words: the 25,000/220,000-star figures reported in late 2002 describe an earlier release than the 26,880/1,457,664-star, magnitude-11.5 figures documented on the developer's own site as of September 2004. Both are real, verified figures — they simply describe different points in the program's development. Readers encountering either number elsewhere should treat it as version-specific rather than as "the" PleiadAtlas star count.

Installed size scaled with how many of the optional databases a user kept: the developer's site lists a full install (all databases) at 5.3 MB, dropping to 3.4 MB without the extended field database, and to 1.4 MB with both field-star databases omitted (main catalog only). PleiadAtlas also required Brian Tung's separate MathLib library (version 1.1 or later) for its floating-point astronomical calculations.

Deep-Sky Objects, Sun, Moon, and Planets

The 2002 review credits PleiadAtlas with the ability to "search and display hundreds of deep-sky objects, the Sun, the Moon, and eight major planets from Mercury to Pluto" — reflecting the pre-2006 IAU classification under which Pluto was still counted as a major planet. The developer's own site independently confirms the deep-sky catalog sources: the full install includes "just about the entire contents of the Messier, NGC, and IC deep sky catalogues." This article did not find confirmation that PleiadAtlas included the Caldwell catalog (a separate 109-object supplemental list compiled by Patrick Moore, published in 1995) and does not assert that it did; only Messier, NGC, and IC are documented in the sources reviewed.

Version History

A complete version history could not be reconstructed from the sources available; the table below lists only what is directly documented, and marks gaps explicitly rather than guessing.

No version numbered later than 2.2.1 was found documented in this research. Whether 2.2.1 was the final release, and if so when development formally stopped, could not be confirmed.

System Requirements and Device Support

PleiadAtlas's own documentation states a requirement of "PalmOS v3.3 and up," with a caveat that it had been "tested with limited success on v3.0." Because Palm III-series and Palm V-series devices generally shipped with Palm OS 3.x, and later Palm and Handspring devices carried this compatibility forward, PleiadAtlas would have run across most of the mainstream Palm OS device lineup of its era, provided a device had sufficient free memory for the databases installed (as little as 1.4 MB for the main catalog alone, up to 5.3 MB for the full install).

This research did not find documentation confirming or denying specific support for Palm OS 5, Sony CLIÉ high-resolution (320×320) screen modes, or any particular device model by name in PleiadAtlas's own materials. Given the "v3.3 and up" requirement statement and no upper version ceiling mentioned, broad backward compatibility with later Palm OS releases through the mid-2000s is plausible but unconfirmed by direct source material, and this article does not assert it as fact.

Memory-card installation was explicitly documented starting with v2.1: the developer's readme states that all files except MathLib.prc, including registration data, could be installed to a card rather than main memory — useful given the multi-megabyte size of the deeper star databases.

Price, Shareware Status, and Registration

By the time of the v2.2.1-era documentation, PleiadAtlas was distributed as nagware/shareware with a $10 registration fee, per both the developer's own comparison table on astronomycorner.net and his separate FAQ document, which describes it plainly as "$10 shareware." The developer's own comparison table (undated, but part of the September 2004 site state) lists competing programs alongside it: PleiadAtlas at $10, Planetarium at $24, 2sky variants at $25–$50, and Star Pilot at $10. This $10 figure should be read as describing the shareware period documented on the developer's site circa 2004, not necessarily the pricing (or licensing model) at the software's original 2000 release as freeware PalmAtlas v0.1, which predates any registration-fee documentation found for this article.

PleiadAtlas vs. Planetarium

Planetarium, a separate and long-lived Palm OS astronomy program, was frequently mentioned alongside PleiadAtlas in contemporary discussion, and Brian Tung's own FAQ places the two head-to-head: Planetarium relied on "the Yale Bright Star Catalogue, containing 9,000 stars to about magnitude 6.5," which is squarely a naked-eye-oriented catalog appropriate for a broad-purpose planetarium and ephemeris tool showing rise/set times, twilight, and moon phase. PleiadAtlas's default catalog alone (25,000 stars to magnitude 7.5, per the 2002 review) already exceeded that depth, before even counting its optional field-star databases. This is not a claim that one program was categorically better — contemporary Cloudy Nights forum users in 2004 and later routinely used both programs side by side for different purposes, as documented below — but it does explain the catalog-depth gap that motivated PleiadAtlas's existence in the first place.

PleiadAtlas vs. 2Sky

2Sky was a competing Palm OS astronomy program from developer Kevin Polk, and its catalog depth was the subject of direct, dated comparison with PleiadAtlas on the Cloudy Nights astronomy forum. Brian Tung's own FAQ document (undated, contemporaneous with the v2.2.1-era site) states that 2Sky's "Basic" edition held "15,560 stars down to magnitude 7" plus 500 deep-sky objects, while its "Total" edition reached "214,000 stars down to magnitude 9.5" — figures Tung presents as smaller than PleiadAtlas's own catalogs.

A Cloudy Nights forum post dated July 23, 2004, titled "New 2Sky coming in August," offers independent, contemporary testimony on the same question from a user (not the developer of either program) who had spoken directly with 2Sky's developer: "The biggest change is that the star database has been expanded out to mag 12, which makes it deeper than any other astronomy program (PleiadAtlas goes to mag 11.5, though it claims to have more stars — something to ponder)." This confirms that, as of mid-2004, informed observers understood PleiadAtlas's full catalog to reach magnitude 11.5 (matching the astronomycorner.net v2.2.1 figures above), while regarding the upcoming 2Sky v3.0 as slightly deeper by limiting magnitude but not necessarily by star count. The same poster noted using "Planetarium, PleiadAtlas, and 2Sky because they all have strengths in certain areas" — underscoring that these were seen as complementary tools by contemporary users, not strict replacements for one another.

Field Use and Longevity

Beyond its original documentation window, PleiadAtlas continued to show up in amateur astronomer discussion for years. A Cloudy Nights thread from June 2004 ("Palm Tungsten T") includes a user asking, "What programs do you guys use for astronomy on your palms? I usually use Planetarium, and sometimes PleiadAtlas, but does anyone use anything they think is superior? Like 2Sky, for instance?" — confirming casual, everyday field use alongside its competitors that same year.

More strikingly, a Cloudy Nights thread from March 2011, "I still love my outdated PDA," shows the software still in active field use nearly a decade after its documented 2002–2004 heyday. Forum user Jon Isaacs wrote: "I am still using Planetarium and PleiadAtlas running on a Palm Tungsten. I primarily use Planetarium, I have it setup the way I want it, I have the databases I need, it is reasonably fast, it runs forever without a recharge, it is robust and it fits in my pocket." This is retrospective, 2011-dated evidence of continued use on a Palm Tungsten-series device, distinct from and much later than the original 2002–2004 documentation discussed above. This article did not find a documented account specifically naming a Palm IIIx or IIIxe in connection with PleiadAtlas; the confirmed 2011 device reference is to a Palm Tungsten, not a IIIx-series unit, and this piece does not claim otherwise.

Availability and Redistribution Today

PleiadAtlas's shareware/nagware licensing terms as documented mean this article cannot confirm redistribution rights for the installer file, and accordingly does not host or mirror it. At the time this article was researched, Brian Tung's own site, astronomycorner.net/PleiadAtlas/, remained reachable and continued to link directly to a v2.2.1 installer package and its accompanying PDF user's guide — making the developer's own site the most legitimate starting point for anyone researching or seeking the original software, rather than third-party ROM or abandonware archives of uncertain provenance. PalmDB.net, a dedicated Palm OS software preservation project, is a reasonable place to check for archival copies of Palm-era software generally, though this research did not turn up a confirmed, working PleiadAtlas listing URL on that site specifically, so no direct link is provided here.

PalmGear Listing and Product ID 14063

PalmGear, the software storefront and catalog this site is restoring backlinks for, listed PleiadAtlas at the historical URL http://palmgear.com/software/showsoftware.cfm?sid=54905620021122082656&prodID=14063, with a stable product identity of prodID 14063. That listing is corroborated by independent references citing the same PalmGear URL alongside the same Shedrick-review description of the software. This restored page documents that listing for historical reference; PalmGear's original hosted software file for this product is not assumed to still be live, and no current download is offered or implied here.

Frequently Asked Questions

Key Takeaways

• PleiadAtlas was developed by Brian Tung and was originally released as freeware called PalmAtlas, with v0.1 unveiled October 27, 2000.
• PalmGear listed the software at product ID 14063, historically reachable at palmgear.com/software/showsoftware.cfm?sid=54905620021122082656&prodID=14063.
• PleiadAtlas was a star-hopping atlas for telescope/binocular field use, not a naked-eye planetarium program — its whole design point was showing more stars than the eye alone could see.
• A December 2002 contemporary review documented a 25,000-star default catalog (magnitude 7.5) and an optional 220,000-star field database (magnitude 9.5).
• By the v2.2.1 release, documented on the developer's site as of September 2004, the full install reached 1,457,664 stars to magnitude 11.5 — a substantially deeper catalog than the 2002-era figures, and the two eras should not be conflated.
• Deep-sky coverage was drawn from the Messier, NGC, and IC catalogs; no Caldwell-catalog support was found documented.
• The software required Palm OS 3.3 or higher; Palm OS 5 and Sony CLIÉ high-resolution support were not confirmed either way in available sources.
• By its 2004-era shareware period, PleiadAtlas cost $10 to register, per the developer's own site and FAQ.
• A July 23, 2004 Cloudy Nights forum post directly compared PleiadAtlas's magnitude-11.5 catalog against the newly announced 2Sky v3.0's magnitude-12 catalog, noting PleiadAtlas "claims to have more stars."
• A March 2011 Cloudy Nights post documents continued field use of PleiadAtlas on a Palm Tungsten-series device nearly a decade after its original documentation window; this article found no documented account specifically tying PleiadAtlas to a Palm IIIx/IIIxe device.
• This research could not access the original astro.isi.edu home of the software; findings instead rely on the developer's later self-hosted mirror, contemporary reviews, and forum testimony.