1   /* Copyright 2002-2017 CS Systèmes d'Information
2    * Licensed to CS Systèmes d'Information (CS) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * CS licenses this file to You under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  You may obtain a copy of the License at
8    *
9    *   http://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
15   * limitations under the License.
16   */
17  package org.orekit.bodies;
18  
19  import java.io.Serializable;
20  
21  import org.hipparchus.RealFieldElement;
22  import org.orekit.errors.OrekitException;
23  import org.orekit.frames.Frame;
24  import org.orekit.time.FieldAbsoluteDate;
25  import org.orekit.utils.PVCoordinatesProvider;
26  import org.orekit.utils.TimeStampedFieldPVCoordinates;
27  
28  /** Interface for celestial bodies like Sun, Moon or solar system planets.
29   * @author Luc Maisonobe
30   * @see CelestialBodyFactory
31   */
32  public interface CelestialBody extends Serializable, PVCoordinatesProvider {
33  
34      /** Get an inertially oriented, body centered frame.
35       * <p>The frame is always bound to the body center, and its axes have a
36       * fixed orientation with respect to other inertial frames.</p>
37       * @return an inertially oriented, body centered frame
38       * @exception OrekitException if frame cannot be retrieved
39       * @see #getBodyOrientedFrame()
40       */
41      Frame getInertiallyOrientedFrame() throws OrekitException;
42  
43      /** Get a body oriented, body centered frame.
44       * <p>The frame is always bound to the body center, and its axes have a
45       * fixed orientation with respect to the celestial body.</p>
46       * @return a body oriented, body centered frame
47       * @exception OrekitException if frame cannot be retrieved
48       * @see #getInertiallyOrientedFrame()
49       */
50      Frame getBodyOrientedFrame() throws OrekitException;
51  
52      /** Get the name of the body.
53       * @return name of the body
54       */
55      String getName();
56  
57      /** Get the attraction coefficient of the body.
58       * @return attraction coefficient of the body (m³/s²)
59       */
60      double getGM();
61  
62      /**
63       * Get the {@link TimeStampedFieldPVCoordinates} of the body in the selected frame.
64       *
65       * @param date  current date
66       * @param frame the frame where to define the position
67       * @param <T>   type fo the field elements
68       * @return time-stamped position/velocity of the body (m and m/s)
69       * @throws OrekitException if position cannot be computed in given frame
70       * @see #getPVCoordinates(org.orekit.time.AbsoluteDate, Frame)
71       */
72      <T extends RealFieldElement<T>> TimeStampedFieldPVCoordinates<T> getPVCoordinates(
73              FieldAbsoluteDate<T> date,
74              Frame frame)
75              throws OrekitException;
76  
77  }