SkyTools
Database Advantages
(1) Speed.
There are actually two databases; a reference database optimized
for efficient access and searching, and a mapping database
optimized for drawing maps. Together, these databases are
efficient enough that drawing maps at any scale or complex
searches can be done directly from the CDROM. These
operations are typically faster than comparable actions using
competing products that are reading directly from the hard
drive.
Not only is SkyTools faster, but
this means that the stellar data need not be transferred to your
hard drive to be used efficiently.
(2) Accuracy. The
astronomical catalogs available today are rife with errors and
inconsistencies. The author of SkyTools drew on his experience
as a professional astronomer to draw together the best data to
make a single entry for each object. This is particularly
important for the stellar database, where the positions and
magnitudes of variable and multiple stars are often
contradictory. An enormous effort went into cross
referencing the stellar data--a task that took years to
accomplish.
As one result, rather than
simply having a multiple star system labeled on the map, if you
zoom in close you will see the system split into its components,
including accurately positioned long period binary stars.
No other software available today can do this with other than
the few widely separated pairs found in the Tycho catalog. And if the "D" component is an HD star
and variable? SkyTools accurately reflects
this. Competing software will typically draw up to
four stars where there is only one in the sky.
One-On-One
Chart Comparison
 Above
is a typical view of the Sigma Ori multiple star system using a
competing product. The symbol with a bar through it
denotes the position of a multiple star (Sigma Ori).
Because the multiple star database has not been integrated, the
symbol does not fall on top of the primary star. To the
upper left we see two stars, one of which has an outer ring
around it to denote a variable. This variable star is in
fact the star to its immediate left, but because the variable
star information has not been integrated it is drawn
twice. In addition, there is a component missing down and
to the right of the primary (brightest) star because it was too
close to be included in the Hipparcos catalog used as a basis
for competing software. Sigma Ori is a wide system; in
practice the majority of multiple star components are too close
to be included. It does not matter which competing product
you try; you will find similar problems to that above.
Above
is the same system as drawn by SkyTools 2. Although not
visible at this scale, the E component of the system is
correctly identified as the variable. Although database errors still exist, they are corrected in the vast
majority of cases.
Competing
software typically shows nothing of interest when zoomed-in past
1'. Above is a
close up of the Sigma Ori primary star drawn at a scale of
1". The star splits to reveal a close companion that
is in orbit about it. SkyTools displays the correct location of
the companion for the date, and can even show all or part of the
orbit as above.
In addition to
displaying the system graphically, SkyTools delivers a great
deal of other information.
 
Another
comparison, this time with the star system Almaak (Gamma1
And). A competitor's product depiction is to the left, and
the SkyTools depiction is on the right. Not only does
SkyTools draw the B and C components, but they too form a long
period binary system, accurately depicted for the date.
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