Introduction

Dealing with minor bodies of the Solar System one badly needs appropriate software tool to plan and treat observations, to estimate parameters of selected groups, to visualize orbital motion, and more. There are several tools of that kind that scientific community has at its disposition, nevertheless we would like to present the new one, AMPLE 3, having a number of merits.

The AMPLE 3 software package does have profound background and reach experience accumulated in its implementation. The very first version of AMPLE (Adaptable Minor PLanet Ephemerides) package had been put forward in 1995. The package got acknowledgement and respect within astronomical community due to its various abilities and features. Abilities of the package are based on, among other factors, high precision elements of minor planets, annually published by the Institute of Applied Astronomy. They are prepared with retention of full accuracy on the basis of orbital elements of new minor planets and elements of improved orbits monthly distributed by Minor Planet Center.

The last fifteen years have seen tremendous progress in both printed version of minor planet ephemerides yearbook and accompanied software package AMPLE. Numerous improvements were made in all parts of the package. Two variants of the package were developed and put in use for specific tasks, i.e., Ample for Comets and MUSE.

The very idea of the new version is to put all innovations together, and gain a stand-alone, consistent, multi-purpose, cross-platform, robust, and easy to use software package AMPLE 3.

AMPLE 3 is integrated software package to deal with a number of problems concerning minor bodies of the Solar System. Among these problems are the following.

• Select minor bodies from catalogues by conditions on orbital elements (three systems of elements are available: (asteroidal, cometary, and equinoctial) and/or photometric parameters and represent resulting data in different graphical forms. We would like to emphasize the slicing òÀÓ new form of presentation for 3-D distributions. Using slicing one can view 2-D distribution slice by slice along with varying of the third dimension.
• Compute ephemerides for specified bodies at given moments in various coordinate systems and with different methods.
• Compare observed positions with computed ones (computation of OòÀÓC).
• Identify numbered minor bodies, which computed positions are sufficiently close to the observed position of unknown object.
• Determine all numbered minor bodies that can be seen at certain moment within specified sky region.
• Draw the picture of apparent motion of minor bodies in the sky with respect to fixed stars.
• Visualize the orbital motion of minor bodies in different ways. What is to be mentioned specially is that we offer ultimate tools for visualization and analysis of approaches.

The use case model of the AMPLE 3 package is presented in figure below. We put in green features released in version 0.4 (December 2009).

What are most important new features of the AMPLE 3 in comparison with previous versions and clones? To put it in short these are five.

1. The package is intended for dealing with all numbered minor planets, numbered periodic comets and non-catalogued objects as well.
2. The package has new smart graphics with effects and animations, including approaches and impacts visualization.
3. The package has modern naturally looking graphical user interface, in which user permanently see what he is going to do in the form of tree-like structured task description.
4. The package could be customized and fine tuned in depth by power user.

Customization and GUI

Every entity that could be considered as a parameter is really the parameter in the AMPLE 3 and could be reset if needed. It could be done by editing XML files with configuration information. For example, we can alter definitions of families and groups as it is shown in the Elem.xml file below. One may edit this xml file on his own responsibility.

 

To make the package do something one have to put the task with standard dialog. All forms for all use cases look alike. The prototype form is shown below.

User has to put parameters of the task one by one in several tabs at the right, and the resulting task appears at the left. To run the current task user has to press Run button, to give it up òÀÓ Cancel button, to save it òÀÓ Save As button, to restore saved one òÀÓ Load button, and to set default task one has to press Default button. Make note that Asteroids and Comets check boxes could be checked or unchecked independently any time.

Elements

The list of minor planet names/preliminary designations, osculating orbital elements, and photometric parameters used in AMPLE 3 contains data on numbered minor planets for some standard epoch lying within the title year of the package. The data base includes 204962 asteroids numbered as of January 2009 and 217 short-periodic comets. Their elements were calculated on 2010 July 23.0 TT. Orbital elements of comets and parameters of nongravitational acceleration A1 , A2 and A3 have been improved by program developed in Institute of Applied Astronomy of RAS.

Present section of the package enables one:

ˆ§        to make selection out of the total number of minor planets in accordance with the restrictions imposed on some element or on a variety of elements;

ˆ§         to sort the obtained selection in order of ascending or descending value of any element;

ˆ§         to draw the histogram of element distribution for obtained selection;

ˆ§         to construct dotty picture of minor planet distribution in two- or three-dimension space of elements.

 

Following designations of elements/ parameters are used in AMPLE 3.

 

H òÀÔ photometric parameter, absolute magnitude in V band

G òÀÔ photometric parameter, so called slope parameter

M òÀÔ mean anomaly

Peri òÀÔ argument of perihelion

Node òÀÔ longitude of ascending node

i òÀÔ inclination

e òÀÔ eccentricity

n òÀÔ mean motion

a òÀÔ semi-major axis.

The angular quantities are expressed in degrees,

n òÀÔ in degrees per day,

a òÀÔ in astronomical units (AU).

 

Apart conventional orbital elements AMPLE gives possibility to calculate for each minor planet the following often used functions:

 

q = a(1òÀÓe) òÀÔ perihelion distance

Q = a(1+e) òÀÔ aphelion distance

p = a(1òÀÓe²) òÀÔ orbital parameter

P = a ^3/2 òÀÔ period of revolution in years

T òÀÔ moment of perihelion passage

Peri+ Node òÀÔ longitude of perihelion

L = Peri+ Node + M òÀÔ mean longitude

n"= nºç3600 òÀÔ mean motion in arcsec/day

dist_ascNode = a(1òÀÓe²)/(1+ecos(Peri)) òÀÔ heliocentric distance of ascending node

dist_dscNode = a(1òÀÓe²)/(1òÀÓecos(Peri)) òÀÔ heliocentric distance of descending node

MOID òÀÔ Minimum Orbit Intersection Distance

CT òÀÔ Tisserand criterion

Dphot òÀÔ photometric diameter

 

To calculate MOID or CT user should put name or number of major or minor planet through dialog.

To gain access to the table of elements press ˆàˆàElements button. Select elements dialog appears (see below). To set constraints on elements choose element, enter values and press Put button. User may select types, groups and families of minor bodies in one click on appropriate checkbox. User may use prepared file with names and numbers of objects also. All subselections are united with logical OR (disjunction). Header tab allows one to chose elements to be shown in the table, no matter what elements are used in constraints. Task description panel shows current task. To run task user should press Run button.

 

 

Table of elements for selected bodies appears. The distribution of elements can be visualized in different ways. See examples below.

 

 

Orbits

To create task for visualization of orbital motion press Orbits button . Orbits visualization dialog appears (see below). To choose the set of objects to be visualized user may:

ˆ§         click checkbox for major planets;

ˆ§         input name or number of minor bodies;

ˆ§         fill special form with parameters for arbitrary noncatalogued object.

To set interval of visualization choose start and end dates. Swarm tab allows to choose large amount of bodies in the same manner as in Elements dialog. Method tab allows to choose the method of calculating coordinates of bodies: by unperturbed elements of orbits, or by nodes, or by numerical integration. Approaches tab allows one to define pair of objects, which approaching is wanted to observe.

Task description panel shows current task. To run task user should press Run button.

 

Result for task Orbits for example can be like below one.

Left hand side panel allows to:

ˆ§         change color palette;

ˆ§         start, stop, suspend and resume motion visualization;

ˆ§         show or hide names, planet spheres and elliptic orbits;

ˆ§         change step and thus speed of motion visualization;

ˆ§         see current time of motion visualization;

ˆ§         depict line of nodes for selected object;

ˆ§         change view point in several ways;

ˆ§         print or save current picture.

 

Moreover, package shows special graphical effect (color blinking), when approaching of two objects takes place. The distance between bodies where the effects is triggered is set in Approaches tab. The minimum distance and the instance when it is attained are shown in Task info panel.

ˆé Institute of Applied Astronomy RAS 2009-2010

E-mails: shor@ipa.nw.ru, fedornovikov@rambler.ru

Mail: Institute of Applied Astronomy, naberezhnaya Kutuzova, 10, Saint Petersburg, 191187, Russia

FAX: +7-812-275-11-19