CN113093259A

CN113093259A - On-orbit gamma ray storm opportunity target observation method

Info

Publication number: CN113093259A
Application number: CN202110417622.4A
Authority: CN
Inventors: 贺俊旺; 陈琨; 苏斌嫔; 苏瑞丰; 毛青筠; 李飞; 张晓峰
Original assignee: Shanghai Engineering Center for Microsatellites; Innovation Academy for Microsatellites of CAS
Current assignee: Shanghai Engineering Center for Microsatellites; Innovation Academy for Microsatellites of CAS
Priority date: 2021-04-19
Filing date: 2021-04-19
Publication date: 2021-07-09
Anticipated expiration: 2041-04-19
Also published as: CN113093259B

Abstract

The invention provides an on-orbit gamma ray riot opportunity target observation method, which carries out opportunity observation on a newly discovered source, a known temporary discovered source or a known temporary variable source, wherein in the operation process of an astronomical observation satellite, when other satellites monitor astronomical events occurring in the universe, an observation task plan is formed after being analyzed by a ground station, and the observation task plan is injected to the astronomical observation satellite so that the astronomical observation satellite executes an observation task; the observation task planning comprises conventional opportunity target observation, important opportunity target observation and multi-messenger opportunity target observation; the importance of the observed objects observed by the important opportunity targets and the multi-messenger opportunity targets is higher than that of the observed objects observed by the conventional opportunity targets; the priority of the important opportunity target observation and the multi-messenger opportunity target observation is higher than that of the conventional opportunity target observation; the observed objects observed by the multiple messenger opportunity targets are larger than the observed objects observed by the important opportunity targets and the conventional opportunity targets.

Description

On-orbit gamma ray storm opportunity target observation method

Technical Field

The invention relates to the technical field of space observation, in particular to an on-orbit gamma ray riot chance target observation method.

Background

Gamma Ray Burst (also called Gamma Burst) is a phenomenon that the intensity of Gamma rays from a certain direction in the sky is suddenly increased in a short time and then rapidly decreased, the duration is 0.1-1000 seconds, and the radiation is mainly concentrated in an energy band of 0.1-100 MeV. Gamma storms were discovered in 1967 for decades, the nature of which was not well understood, but could basically be determined to be an explosive process that occurs in sidereal celestial bodies on a cosmic scale. Gamma storm is currently one of the most active research areas in astronomy, and was rated by the U.S. J.Sci.Sci.in 1997 and 1999 as a ten year advance in science and technology.

Gamma ray storms are the strongest phenomenon of detonation in the universe known today, and theoretically result from the collapse and explosion of a giant star at fuel exhaustion or the merger of two adjacent dense stars (black holes or stars). Gamma ray exposure is as short as a thousandth of a second and as long as hours, it releases a large amount of energy in a short time. If compared to the sun, it releases energy equivalent to the sum of trillion years of sunlight in a few minutes, with the emitted single photon energy being typically hundreds of thousands of times that of typical sunlight.

The energy mechanism of the gamma ray storm is still far from being solved, and the energy mechanism is also the core problem of the research of the gamma ray storm. With the advancement of technology, the human beings can further understand the universe, a plurality of problems which are still riddle at present can be solved in the future, the exploration of the mysterious secret is necessary for the human beings to pursue scientific progress, and the unbundling of the riddles can finally benefit the human beings. However, how to find, locate and measure various gamma ray storms to study the evolution and dark energy of the universe is a difficult problem in the field of astronomy at the present stage.

Disclosure of Invention

The invention aims to provide an on-orbit gamma ray storm opportunity target observation method to solve the problem that the existing gamma ray storm observation difficulty is high.

In order to solve the above technical problems, the present invention provides an on-orbit gamma ray exposure opportunity target observation method, which performs opportunity observation on a newly discovered source, a known transient source or a known transient source, and includes:

in the operation process of the astronomical observation satellite, after other satellites monitor astronomical events occurring in the universe, an observation task plan is formed after the analysis of a ground station, and the observation task plan is injected to the astronomical observation satellite so that the astronomical observation satellite executes an observation task;

the observation task planning comprises:

and the multi-messenger opportunity target observation carries out a multi-pointing and splicing type observation mode, the observation target is divided into a plurality of pieces, and an observation path is planned according to the priority and the maneuvering angle of each piece, so that the astronomical observation satellite observes the plurality of pieces of targets.

Optionally, in the method for observing on-orbit gamma ray chance targets, the frequency of observing multiple messenger chance targets is expected to be 1 time per week;

the observation duration of the multi-messenger opportunity target observation is not more than 14 tracks, the number of targets observed in a single track is not more than 5, and the observation time of each target is 10 minutes;

during the normal operation of an astronomical observation satellite, 5 targets are selected in a range of 10 degrees multiplied by 10 degrees in a single track,

during extended operation of the astronomical observation satellite, 10 ° x 10 ° is not constrained.

Optionally, in the method for observing an on-orbit gamma ray riot opportunity target, the observation task plan further includes observation of a conventional opportunity target and observation of an important opportunity target;

the importance of the observed objects observed by the important opportunity targets and the multi-messenger opportunity targets is higher than that of the observed objects observed by the conventional opportunity targets;

the priority of the important opportunity objective observations and the multi-messenger opportunity objective observations is higher than the priority of the regular opportunity objective observations;

the observed objects observed by the multiple messenger opportunity targets are larger than the observed objects observed by the important opportunity targets and the conventional opportunity targets.

Optionally, in the on-orbit gamma ray chance target observation method, the priority of the conventional chance target observation is lower than that of the gamma ray chance observation and reproduction source observation and higher than that of the conventional observation, and the priority of the important chance target observation and the multi-messenger chance target observation is higher than that of the gamma ray chance observation and reproduction source observation;

the gamma storm observation includes:

after a gamma ray storm is detected through a high-energy load with a wide view field, an astronomical observation satellite is triggered to obtain a position parameter, an energy spectrum parameter and an optical variation parameter of the gamma ray storm, and the position parameter, the energy spectrum parameter and the optical variation parameter are provided for a ground station in real time through a VHF wave band;

the astronomical observation satellite autonomously and rapidly performs attitude maneuver according to the triggering information of the gamma ray storm positioned by the high-energy load, and performs continuous observation of optical afterglow on the gamma ray storm;

in observation, the astronomical observation satellite keeps high attitude stability and ensures the detection performance of the optical telescope.

Optionally, in the method for observing an on-orbit gamma ray riot opportunity target, during the normal operation of the astronomical observation satellite, the astronomical observation satellite performs normal opportunistic target observation once a day, wherein the normal opportunistic target observation accounts for 15% of the total effective observation time;

during the extended operation period of the astronomical observation satellite, the astronomical observation satellite performs five times of conventional opportunistic target observation every day, wherein the conventional opportunistic target observation accounts for more than 40% of the effective time of all observation;

and (4) carrying out calibration test on the load instrument by utilizing conventional opportunistic target observation.

Optionally, in the method for observing the on-orbit gamma ray exposure targets, the expected frequency of the important exposure target observation is 1 time per month.

Optionally, in the method for observing an on-orbit gamma ray exposure target, the observing direction of the on-orbit gamma ray exposure target includes: the included angle between the sun and the + Xs axis of the astronomical observation satellite is larger than 90 degrees, and the + X surface of the astronomical observation satellite is prevented from being irradiated by the sun;

the included angle between the sun and the + Y surface of the astronomical observation satellite or the-Y surface of the astronomical observation satellite is less than 5 degrees;

the included angle between the sun and the-Zs axis of the astronomical observation satellite is larger than 90 degrees, and the-Z surface of the astronomical observation satellite is ensured not to be irradiated by the sun.

Optionally, in the method for observing on-orbit gamma ray storm opportunity targets, the observation tasks of conventional opportunity target observation include a conventional opportunity gamma storm revisiting target task, a conventional opportunity supplement calibration target task, and a conventional opportunity celestial body target task;

the observation process of observing the satellite conventional chance targets comprises the following steps:

the method comprises the steps that a ground station notes one day of conventional opportunity target observation tasks, including 1-5 observation tasks, including a conventional opportunity target observation platform task package and a load configuration table;

at the time of starting the task, the housekeeping computer carries out constraint judgment according to the task mode constraint; if all the constraints pass, the satellite maneuvers, points to the target and synchronously broadcasts the current task ID;

after the satellite motor-driven operation is finished, rotating the sailboard according to the sailboard rotation strategy;

the load data processing computer configures VT working parameters according to the current task ID, a task packet of a conventional chance target observation platform and a load configuration table;

the high energy load remains in the current mode.

Optionally, in the method for observing on-orbit gamma ray exposure targets, the observation of important exposure targets includes an immediate task and a delayed task, where:

the observation process of the satellite important opportunity target observation is as follows:

injecting 1 important opportunity target observation task on the ground station, wherein the 1 important opportunity target observation task comprises an important opportunity target observation platform task packet and a load configuration table;

according to the time parameter in the task packet of the important opportunity observation platform, the housekeeping computer immediately or according to the set time point carries out constraint judgment according to the task mode constraint;

if all the constraints pass, the satellite maneuvers, points to the target and synchronously broadcasts the current task ID;

the load data processing computer configures VT working parameters according to the current task ID, the important opportunity target observation platform task packet and the load configuration table;

the high energy load remains in the current mode;

the newly-annotated important opportunity target observation can interrupt the current important opportunity target observation task.

Optionally, in the method for observing on-orbit gamma ray riot chance targets, an observation process of observing on-board multiple messenger chance targets is as follows:

injecting a multi-messenger opportunity target observation task on the ground, wherein the multi-messenger opportunity target observation task comprises a multi-messenger opportunity target observation platform task package and a load configuration table;

when a certain piece starts, carrying out constraint judgment according to task mode constraint conditions;

when the front-sheet constraint is not passed, keeping the current task;

when the next task starts, constraint judgment is continuously carried out according to the task mode constraint conditions;

if all the constraints of all the slices pass, the satellite maneuvers, points to the target and synchronously broadcasts the current task ID;

the load data processing computer configures VT working parameters according to the current task ID, the multi-messenger opportunity observation platform task packet and the load configuration table to generate a VHF data packet observed by the multi-messenger opportunity;

the high energy load remains in the current mode;

the step after the starting time of the slices is switched to continues to be carried out until the execution of all the slices is finished;

newly annotated multi-messenger opportunity observation can interrupt the current important opportunity observation task.

In the on-orbit gamma ray storm opportunity target observation method provided by the invention, a new discovery source, a known temporary discovery source or a known temporary variable source are subjected to opportunity observation, in the operation process of an astronomical observation satellite, after other satellites monitor astronomical events occurring in the universe, an observation task plan is formed after ground station analysis, the observation task plan is injected to the astronomical observation satellite so that the astronomical observation satellite executes observation tasks, and the observation task plan comprises different priorities and different observation target sizes which are divided into various observations, so that the observation flexibility can be improved, and the continuity, the accuracy and the reliability of gamma ray storm observation can be improved.

In addition, the astronomical observation satellite achieves the advantage of high on-satellite autonomous capability through the characteristics of rapid satellite maneuvering, on-satellite autonomous management and the like, and overcomes the problem of complex task mode. Besides the ground planning task, the system also coordinates various on-satellite autonomous observation tasks, and realizes cooperative management of the ground planning task and the on-orbit autonomous trigger task on the satellite.

Drawings

FIG. 1(a) is a schematic diagram of an observation target for ToO-MM observation of GW170814 according to an embodiment of the present invention;

FIG. 1(b) is a schematic diagram illustrating an implementation of ToO-MM observation for GW170814 according to an embodiment of the present invention;

FIG. 2 is a schematic view of an anti-solar pointing embodiment of the present invention;

FIG. 3 is a schematic diagram of the relationship between the sun and the satellite pointing downwards according to an embodiment B1 of the present invention;

FIG. 4 is a schematic view of an embodiment of the present invention B1 pointing downward into the ECLAIRs field of view trajectory;

FIG. 5 is a schematic view of the change in the included angle between the sun and the-Xs axis according to an embodiment of the present invention;

FIG. 6 is a schematic diagram of an observation direction of a GRB according to an embodiment of the present invention;

FIG. 7 is a schematic diagram illustrating an on-board task management process according to an embodiment of the present invention;

fig. 8 is a schematic diagram of a task switching process on a satellite according to an embodiment of the present invention.

Detailed Description

The on-orbit gamma ray exposure target observation method proposed by the invention is further explained in detail with reference to the drawings and the specific embodiment. Advantages and features of the present invention will become apparent from the following description and from the claims. It is to be noted that the drawings are in a very simplified form and are not to precise scale, which is merely for the purpose of facilitating and distinctly claiming the embodiments of the present invention.

Furthermore, features from different embodiments of the invention may be combined with each other, unless otherwise indicated. For example, a feature of the second embodiment may be substituted for a corresponding or functionally equivalent or similar feature of the first embodiment, and the resulting embodiments are likewise within the scope of the disclosure or recitation of the present application.

The core idea of the invention is to provide an on-orbit gamma ray storm opportunity target observation method to solve the problem of high difficulty in the existing gamma ray storm observation.

In order to realize the idea, the invention provides an on-orbit gamma ray riot opportunity target observation method which carries out opportunity observation on a newly discovered source, a known transient source or a known transient source, and the method comprises the following steps: in the operation process of the astronomical observation satellite, after other satellites monitor astronomical events occurring in the universe, an observation task plan is formed after the analysis of a ground station, and the observation task plan is injected to the astronomical observation satellite so that the astronomical observation satellite executes an observation task; the observation task planning comprises conventional opportunity target observation, important opportunity target observation and multi-messenger opportunity target observation; the importance of the observed objects observed by the important opportunity targets and the multi-messenger opportunity targets is higher than that of the observed objects observed by the conventional opportunity targets; the priority of the important opportunity objective observations and the multi-messenger opportunity objective observations is higher than the priority of the regular opportunity objective observations; the observed objects observed by the multiple messenger opportunity targets are larger than the observed objects observed by the important opportunity targets and the conventional opportunity targets.

The invention adopts astronomical observation satellites to discover and position, measures various Gamma-Ray bursts (GRB) and other high-energy transient phenomena (including X-Ray explosion, soft Gamma repeated explosion, active star system AGN, new star and the like), and researches the evolution and the dark energy of the universe. The satellite has the characteristics of on-satellite autonomous target discovery, rapid satellite maneuvering, on-satellite autonomous management and the like, and is one of the satellites with highest on-satellite autonomous capability requirement and the most complex task mode at present. Besides the on-satellite autonomous observation task, the on-satellite autonomous observation task also has various ground planning tasks, and the on-satellite autonomous trigger task and the on-orbit autonomous trigger task need to be managed cooperatively.

According to the system requirements, a plurality of on-orbit observation modes are designed, wherein the on-orbit observation modes comprise four major classes of gamma storm observation (GRB), reproduction source observation (CAT), General observation (GP) and Opportunity Target (Target of Opportunity, ToO) observation, wherein the ToO observation comprises conventional Opportunity Target (ToO-NOM) observation, important Opportunity Target (ToO-EX) observation and Multi-messenger Opportunity Target (ToO-MM) observation.

Narrow field loads include soft X-ray telescopes MXT and optical telescopes VT, wide field loads include hard X-ray cameras eclairrs and gamma ray monitors GRM.

Due to uncertainty of on-satellite autonomous observation opportunity, target pointing and the like, the ground station cannot predict the current on-orbit observation mode, attitude pointing, energy and other conditions of the satellite. In order to ensure the safety of the load and the satellite and the effectiveness of scientific data, multiple constraint conditions such as solar constraint, moon constraint, energy constraint and the like are calculated and judged before a new observation task is executed. Therefore, the on-orbit observation mode and autonomous management are the key points for the success or failure of the satellite observation task.

The astronomical observation satellite in-orbit observation mode comprises four types of observation tasks of GRB, CAT, GP and ToO observation, wherein GP observation is planned observation on a known source or a day area in advance, and ToO task is opportunity observation on a newly discovered source or a known temporary discovered source/variable source. GRB and CAT are on-satellite autonomous trigger tasks for gamma storm observation.

In one embodiment of the present invention, a GRB observation requirement is provided, wherein GRB observation is a main task of an astronomical observation satellite, and can be triggered by on-board and ground cooperation observation or on-board independently to complete GRB observation, and the on-board main work includes: the satellite detects the triggering of the gamma storm through the wide view field load, obtains the parameters of the detected gamma storm, such as the position, the energy spectrum, the light variation and the like, and provides the parameters to the ground in near real time through a VHF wave band; the satellite autonomously and rapidly performs attitude maneuver according to gamma storm triggering information positioned by wide view field load, and performs continuous observation of optical afterglow on the gamma storm; the satellite keeps high attitude stability (0.8'/100 s) and ensures the detection performance (22.5Mv) of the optical telescope; the satellite can observe according to the observation time of the GRB set on the satellite, and the default is to continuously observe 14 orbits. At least 200 gamma storms of various types are expected to be detected and located during an astronomical observation satellite mission, including: short exposures (of a few milliseconds to 1-2 seconds in duration), long exposures (of a duration of up to 1,000 seconds), and gamma exposures that are particularly rich in X-rays (e.g., gamma exposures in which the radiation is predominantly below the energy band of 30 keV).

In one embodiment of the invention, a CAT observation requirement is provided, the CAT observation is very similar to the GRB observation, the main difference is that a known gamma storm information list is stored in the wide-field load of the CAT observation, once the source and location of the gamma storm target are found successfully, the wide-field load is compared with the stored list, if the detected target is the stored target, the observation is the CAT observation, otherwise, the observation is the GRB observation. The rest of the processing flow on the satellite is consistent with the observation of GRB. The content of the gamma storm information list (the observed sources and corresponding thresholds) is continuously updated during the task.

In one embodiment of the invention, a GP observation requirement is proposed, the GP observation being a ground planning task, waiting for a GRB trigger. The orientation of GP observation plan is beneficial to finding the gamma storm, and the observation seamlessly covers the whole observation period. GRB or ToO observations can interrupt GP observations. And after the GRB or ToO observation is finished, the motor is returned and the observation which is originally executed at the current moment in the GP observation task is executed. The calibration test of the loading instrument is also one of GP observations. During the normal operation period (within 3 years of the assessment life) of the satellite, the GP tasks account for at least 60% of the total effective observation time. During extended satellite operation (beyond 3 years of life), GP missions are reduced to 35%.

In one embodiment of the invention, a need for a ToO observation is provided, wherein the ToO observation is an observation-worthy astronomical event which suddenly occurs in the universe during the operation of a satellite and can be discovered by other satellites, analyzed by scientists, planned by a ground station and annotated to an observation task performed by the satellite. The ToO observation is divided into three subclasses of conventional opportunity target (ToO-NOM) task observation, important opportunity target (ToO-EX) task observation and multiple messenger opportunity target (ToO-MM) task observation.

Astronomical emergencies where the ToO-NOM observation is important can be interrupted by GRB observations. The ToO-NOM observation also supports calibration testing of load instruments. Secondly, the ToO-EX observation object is a very important astronomical event or target and has very strong observation value, and during observation, the satellite does not respond to the GRB detected on the satellite. The expected frequency of such chance targets is 1 per month. Finally, the ToO-MM observation object is also a very important astronomical event or target, but the target is large and cannot be fully covered by one-time observation, so the multi-directional and splicing observation mode is designed, the target is divided into a plurality of pieces (tiles), and the path is reasonably planned according to priority, maneuvering angle and the like, so that the target is observed.

Fig. 1(a) shows an observation target, and fig. 1(b) shows that the observation target is divided into a plurality of tiles according to the observation requirement of the ToO-MM, about 5 tiles are selected in the range of 10 degrees multiplied by 10 degrees per track according to a target planning algorithm given by the system by considering factors such as priority, field of view and the like, and each tile realizes effective observation time of about 10 minutes. The ToO-MM observations during the development test may no longer be constrained for 10 ° × 10 °.

The invention also provides a plurality of observation directions in an on-orbit observation mode, wherein during observation of an astronomical observation satellite, the observation directions mainly comprise GP directions, ToO directions and GRB/CAT directions, and the directions all have to meet the anti-solar direction requirement, as shown in figure 2, the observation directions mainly comprise: the included angle between the sun and the + Xs axis is larger than 90 degrees, and the + X surface is ensured not to be irradiated by the sun; the included angle between the sun and the + Y surface or the-Y surface is less than 5 degrees; the included angle between the sun and the-Zs axis is larger than 90 degrees, and the-Z surface is ensured not to be irradiated by the sun.

In one embodiment of the present invention, a GP pointing is proposed, which is typically located within ± 10 ° of a satellite reference pointing optimized for gamma storm detection (i.e., "B1 pointing"), while the field of view of the narrow-field instrument is not obscured by the earth. B1 is directed to adopt an optimized anti-sun pointing scheme, as shown in fig. 3, the anti-sun pointing scheme can ensure that the detected gamma storm is located at the earth shadow side, so that the ground telescope can observe at night, and on the basis of anti-sun, the following factors need to be considered: special day zones such as ScoX-1 and the Galaxy zone which have influence on GRB detection are avoided; the observation of a large ground telescope is facilitated in the observed sky area; provides a good thermal environment for the load, so that the load is not influenced by the sun before and after the attitude maneuver. According to the distribution of the large ground telescopes, the satellite pointing direction should be as close to the equator of the sky as possible, and if the declination of the pointing direction is between-21 degrees and +25 degrees, all three large telescopes have the opportunity to observe the detected gamma storm. B1 points to the edge locus of the downward wide field loading field as shown in fig. 4. As can be seen from fig. 4, the wide field of view payload field avoided the galaxy belt and Scox1 celestial bodies well during the running observation. Because the relative relationship between the sun and the satellite is satisfied, the satellite needs to rotate around the Xs axis, and the rotation of the field edge caused by the rotation can be seen from the figure. The sun was held at a 45 ° angle to the + Z plane, which in some special cases could be up to 62 ° due to avoidance of Scox1 from the galaxy river, as shown in fig. 5. To introduce GP observation planning flexibility, it is also defined that the proportion of ± 10 ° beyond the reference point increases with observation time, about 10% beyond during normal operation of the project, and gradually increases to 50% during expansion.

In one embodiment of the invention, a ToO pointing is proposed, the ToO observation does not need to follow a reference pointing, only an anti-solar pointing is guaranteed.

In one embodiment of the invention, it is proposed that the GRB pointing/CAT pointing, the GRB events occur randomly anywhere within the wide field of view load field, the angle of the maneuver at the GRB view is +/-45 ° at the maximum. This orientation after the maneuver is referred to as the GRB orientation, as shown in FIG. 6.

The invention also provides a Management method of the on-orbit observation mode, which specifically comprises the overall design of the observation mode, the Satellite on-Satellite observation is realized by combining an SMU (Satellite Management Unit) and a PDPU (Payload Data Processing Unit) according to the observation requirement, and the specific flow is shown in FIG. 7. As can be seen from fig. 7, the on-satellite observation task is managed by the SMU and the PDPU together, the PDPU mainly manages the on-satellite triggered task, and the SMU comprehensively manages the ground planning and the on-satellite autonomously triggered observation task.

In one embodiment of the present invention, observation mode switching management is proposed, and fig. 8 shows various observation mode switching diagrams. The management process of the ground planning task is as follows: the ground station sends GP, ToO platform task lists to be stored in the SMU; storing load configuration tables corresponding to GP and ToO tasks sent by the ground station in the PDPU; when the task starts, the SMU carries out constraint judgment according to the task mode constraint conditions; if all the constraints pass, the satellite maneuvers to point to the target; synchronously broadcasting the current task ID; the PDPU configures load working parameters according to the task ID and the settings in the load configuration table; and rotating the sailboard according to the sailboard rotating strategy. And keeping the current pointing direction and waiting for the next task.

In one embodiment of the present invention, an on-satellite autonomous triggering management procedure is proposed as follows: the PDPU receives the wide view field load trigger packet in real time and forwards the wide view field load trigger packet to the ground station through the VHF channel; the PDPU judges a maneuvering request mark in the wide-view-field load triggering package, when the maneuvering request is effective, the PDPU calculates included angles (solar constraint and moon constraint) between the target direction and the sun and the moon according to the position information in the wide-view-field load triggering package, and judges whether the target is suitable for satellite observation. When the sun constraint and the moon constraint are passed, the PDPU converts the target direction into an attitude quaternion and sends the attitude quaternion to the SMU. The subsequent SMU processing flow comprises: when the task starts, the SMU judges according to the task mode constraint condition; if all the constraints pass, the satellite maneuvers to point to the target; synchronously broadcasting the current task ID; the PDPU configures load working parameters according to the current task ID and the setting in the load configuration table; and rotating the sailboard according to the sailboard rotating strategy. And keeping the current pointing direction and waiting for the next task. The task mode constraint conditions comprise priority higher than that of the current on-orbit observation mode, solar constraint, moon constraint, energy constraint and sailboard rotation strategy.

The invention also provides an observation constraint design and management method, which comprises attitude maneuver constraint, wherein when a task is responded, the astronomical observation satellite needs to maneuver and point to a target, and other task interruption requests are not responded in the process. The method also comprises priority management, wherein the priority of various tasks (in-orbit observation mode) of the astronomical observation satellite is from low to high according to the system requirements and definitions: GP task < ToO-NOM task < GRB/CAT task < ToO-EX task/ToO-MM task; it can be seen that the task with the lowest priority is the GP task, the GRB and CAT tasks are the same priority, the ToO-EX task and the ToO-MM task are the same priority, and the priority is the highest, so that the GRB and CAT tasks can be interrupted. The newly annotated ToO-EX and ToO-MM tasks may interrupt the original ToO-EX and ToO-MM tasks.

Specifically, the astronomical observation satellite performs two solar constraint and moon constraint checks on all tasks. For GP and tos missions, ground pre-tightening checks were performed to confirm that the solar constraint and the lunar constraint were passed through the remarks. For two on-satellite autonomous triggering tasks of GRB and CAT tasks, PDPU is adopted to strictly check and confirm that solar constraint and moon constraint are passed, and then the tasks are forwarded to the SMU. The SMU checks sun and moon constraints as required for all task requests.

In one embodiment of the invention, solar constraint is proposed, and the PDPU judges that the included angle between the sun and the satellite needs to meet the following requirements: angle 1[ sun, satellite + X axis ] >91.1 °; the SMU judges that the included angle of the solar constraint needs to meet the following requirements: the angle 1[ sun, satellite + X axis ] >89.9 °, the angle 2[ sun, satellite + Y axis ] >85 °, the angle 3[ sun, satellite-Y axis ] >85 °, the angle 4[ sun, satellite-Z axis ] >89 °. The above parameters support the ground command to modify the parameter values.

In an embodiment of the invention, a moon constraint is proposed, and the PDPU determines that the moon occlusion constraint can be selected from the following three cases: angle 1[ moon, satellite + X axis ] >22 ° (VT), angle 2[ moon, satellite + X axis ] >12 ° (MXT), unconstrained. The SMU judges that moon occlusion is restricted by the following three conditions: angle 1[ moon, satellite + X axis ] >20.4 ° (VT), angle 2[ moon, satellite + X axis ] >10.4 ° (MXT), unconstrained. The above parameters support the ground command to modify the parameter values.

In one embodiment of the invention, energy constraint is provided, and the discharge depth of the storage battery needs to be judged before the task is executed in order to ensure energy safety. Parameter 1: the current storage battery discharge depth is more than 20%; parameter 2: expected maximum depth of discharge > 20%; the parameters support the ground instruction to modify the parameter values and support the shielding/opening function.

In one embodiment of the invention, a sailboard rotation strategy is provided, and the sailboard rotation time corresponding to different tasks is as follows: designing sailboard inhibition time when executing GRB/CAT task, and rotating the sailboard after the inhibition time; the inhibition time of the sailboard is defaulted to 15min and is adjustable according to instructions. And (3) when executing GP, ToO-NOM, ToO-EX and ToO-MM tasks, rotating the sailboard after the posture meets the task requirements (namely entering the conventional pointing/high-precision pointing). The windsurfing boards follow the following turning strategy: condition 1: the predicted rotation angle of the sailboard is less than or equal to 10 degrees (default 10 degrees, on-orbit adjustable), and the sailboard is kept still; condition 2: (1) the predicted rotation angle of the sailboard is more than 10 degrees (adjustable on the track) at an angle of more than or equal to 30 degrees (2) the discharge depth of the current storage battery pack is less than 10 percent (adjustable on the track); when the requirements of (1) and (2) are met, the sailboard is kept still; condition 3: in other cases, the windsurfing board is turned.

The invention also provides different observation process designs of each on-orbit observation mode, which comprise the observation process designs of gamma storm (GRB)/reproduction source (CAT), conventional (GP) and opportunity target (ToO).

Specifically, the gamma storm (GRB)/reproduction source (CAT) observation process includes: after the GRB task and the CAT task are both positioned by the wide view field load, the satellite autonomously observes, and the difference is that the source detected by the CAT task is recorded in a source directory list of the wide view field load. The wide view field load and GRM in the astronomical observation satellite can find gamma storms, and the gamma storms are confirmed by the wide view field load and then sent to the PDPU, specifically as follows: if the gamma ray monitor GRM detects a gamma storm, generating a GRM trigger packet, forwarding the GRM trigger packet to the wide view field load through the PDPU, and generating the wide view field load trigger packet after the wide view field load is confirmed; if the wide view field load detects the gamma storm, the wide view field load trigger packet is directly generated. The GRB and CAT task flow is as follows: through the wide view field load trigger packet, the wide view field load can collect the positioning information of GRB (including trigger time T0, gamma storm at ECL view field position), and the positioning information is forwarded by PDPU and then is downloaded to the ground station by VHF; if the position accuracy of the GRB is better than 13-angle division, the wide-field load maneuvering request flag is set to be effective; and (3) the PDPU calculates the included angle (solar constraint and moon constraint) between the target direction and the sun and moon according to the constraint condition of GRB direction, and calculates the judgment condition whether the included angle is larger than the PDPU in the task mode constraint condition. If the sun constraint and the moon constraint are passed, the PDPU converts the target direction into an attitude quaternion and sends the attitude quaternion to the SMU; the SMU judges according to the task mode constraint condition; after all the constraint conditions of the task mode constraint conditions pass, the satellite starts maneuvering (time T1), the narrow-view load is enabled to point to the position of the GRB within 5 minutes, and the current task ID is synchronously broadcast; after the satellite attitude stability meets the requirement (80 ℃), carrying out high-precision observation and positioning on GRBs (glass fiber reinforced plastics) by using the narrow view field load, generating a high-precision positioning packet, forwarding the high-precision positioning packet by using PDPU (polymer dispersed polyurethane), and downloading the high-precision positioning packet to a ground station by using VHF (very high frequency); the high-precision positioning packet comprises the optimization direction and the quality factor QF value of the current target; when the QF value in the high-precision positioning packet is more than or equal to 2 and the current GRB observation does not exceed 2 tracks, the PDPU sends a GRB optimization pointing request at the next conventional maneuvering point; the SMU receives an optimization request sent by the PDPU, judges according to a task mode constraint condition, after all the constraint conditions of the task mode constraint condition pass, the satellite starts secondary maneuvering, and only once optimization pointing is carried out on a primary GRB/CAT task; the PDPU configures VT working parameters according to the current task ID, the information in the high-precision positioning packet and GRB task parameters prestored on the satellite and VT management time sequence to generate VHF and X-band channel data; the GRM generates corresponding VHF and X-band channel data according to the current task ID and the current task mode; the gamma ray monitor and the hard X-ray camera begin waiting for the next GRB trigger; (T1+15) minutes (adjustable, 15-30 minutes), rotating the sailboard according to the sailboard rotating strategy; after the current GRB task is observed for 97 minutes (adjustable), the SMU accepts new GRB trigger, and the GRB task within 97 minutes is rejected and discarded; without interruption of the current GRB mission, the observation will continue for 14 orbits (tunable), and the satellite then returns to GP or to the to-NOM observation.

In one embodiment of the present invention, a conventional (GP) observation procedure includes: and in the case of no GRB, the GP observation task performs conventional observation on the scientific target which is planned and annotated ahead by the satellite, and waits for the GRB to trigger. GP observations include conventional preplanned observation (GP-PPT) and conventional scaled observation (GP-CAL) tasks. GP-PPT missions are typically observed within + -10 deg. of the satellite reference heading optimized for gamma storm detection (i.e., "B1 heading"). The GP-CAL task is used for load scaling, planned once in approximately three months. The ground support system plans the pointing direction according to the observation requirement of the GP task, generates a GP task package after verifying that the sun constraint, the moon constraint and the like are met, and then injects the GP task package to the satellite. The onboard GP observation process is as follows: injecting GP tasks of one week on the ground, wherein the GP tasks comprise a GP platform task packet, a GSP packet and a load configuration table; covering GP tasks at the whole time, wherein 7-98 tasks are covered every week; when the task starts, the SMU carries out constraint judgment according to the 'task mode constraint condition'; if all the constraint conditions pass, the satellite maneuvers to point to the target; synchronously broadcasting the current task ID; after the satellite motor-driven operation is finished, rotating the sailboard according to the sailboard rotation strategy; the PDPU configures VT working parameters according to the current task ID and the VT load configuration table; the GRM maintains the current mode.

In one embodiment of the present invention, a chance targets (ToO) observation process comprises: conventional chance target (ToO-NOM) observation process, important chance target (ToO-EX) observation process, and multiple messenger chance target (ToO-MM) observation process.

The conventional opportunistic object (ToO-NOM) observation process comprises the following steps: the ToO-NOM observation can interrupt the GP task and can be interrupted by the GRB/CAT task. The ToO-NOM observation comprises tasks of a conventional chance GRB revisit target (ToO-NOM-GRB), a conventional chance supplement calibration target (ToO-NOM-ACAL) and a conventional chance celestial object target (ToO-NOM-AT). The on-satellite ToO-NOM observation process is as follows: injecting a one-day ToO-NOM task on the ground, wherein the ToO-NOM task comprises a ToO-NOM platform task package and a load configuration table; 1-5 tasks per day; when the task starts, the SMU carries out constraint judgment according to a 'task mode constraint condition'; if all the constraints pass, the satellite maneuvers to point to the target; synchronously broadcasting the current task ID; after the satellite motor-driven operation is finished, rotating the sailboard according to the sailboard rotation strategy; the PDPU configures VT working parameters according to the current task ID and the VT load configuration table; the GRM maintains the current mode.

The important opportunity objective (ToO-EX) observation is the highest priority task and can be configured to be executed immediately and executed with a delay. The frequency of ToO-EX observations is expected to be 1 per month. The on-satellite ToO-EX observation process is as follows: annotate 1 ToO-EX task on the ground, including ToO-EX platform task package and load configuration table; according to the time parameter in the platform task packet, the SMU immediately or according to a set time point carries out constraint judgment according to a 'task mode constraint condition'; if all the constraints pass, the satellite maneuvers to point to the target; synchronously broadcasting the current task ID; after the satellite motor-driven operation is finished, rotating the sailboard according to the sailboard rotation strategy; the PDPU configures VT working parameters according to the task ID and the VT load configuration table; the GRM maintains the current mode. The newly annotated ToO-EX or ToO-MM task may interrupt the current ToO-EX task.

The multiple messenger opportunity targeting (ToO-MM) observation is a spliced observation, a task package comprises a plurality of tiles, namely a plurality of orientations, no more than 5 tiles are arranged in a single track, and the observation time of each tile is about 10 minutes. The manoeuvrability angle of tiles in a rail does not exceed 10 °. The duration of the ToO-MM observation task does not exceed 14 tracks, so that the number of tiles in one ToO-MM task does not exceed 75. The frequency of ToO-MM observations is expected to be 1 per week. The on-satellite ToO-MM observation process is as follows: injecting a ToO-MM task on the ground, wherein the ToO-MM task comprises a ToO-MM platform task package and a load configuration table; carrying out constraint judgment according to a task mode constraint condition at tile starting time; the current tile constraint is not passed, and the current task is kept; continuously carrying out constraint judgment according to the 'task mode constraint condition' when the next tile starts; if all the constraints pass, the satellite maneuvers to point to the target; synchronously broadcasting the current task ID; after the satellite motor-driven operation is finished, rotating the sailboard according to the sailboard rotation strategy; the PDPU configures VT working parameters according to the task ID and the VT load configuration table to generate a VHF data packet of the ToO-MM; the GRM maintains the current mode. And continuing the steps after the tile starting time is transferred until all tiles are executed.

The invention also provides an observation task constraint conflict judgment strategy, an astronomical observation satellite has an autonomous planning task on the satellite, the ground cannot predict the current satellite state, and the astronomical observation plans the treatment measures of different observation tasks when the satellite is in the maneuvering process and the energy condition, the sun condition and the moon condition are not suitable for developing the observation, which is specifically shown in table 1.

Table 1 constraint not-passing task handling table

Description of the drawings: strategy 1: aiming at GP, ToO-NOM and ToO-EX observation tasks, when the tasks are rejected because of the movement and the unsatisfied energy conditions, the tasks are executed only at the next GSP time point; strategy 2: for the ToO-MM observation task, the next tile has an opportunity to be executed only when the current tile is rejected. Table 2 shows the handling measures at each task conflict.

TABLE 2 task conflict resolution TABLE

Table 3 gives the information of priority, start time, end time, duration, etc. of the different task modes.

TABLE 3 task management planning

Description of the drawings: the smaller the priority value, the higher the priority.

Aiming at the complex diversity of observation modes of an astronomical observation satellite, the invention deeply analyzes the importance of different tasks, designs a plurality of observation mode management processes such as GP observation, ToO observation, GRB observation, CAT and the like by combining target characteristics and various constraint conditions, and formulates a judgment strategy for task conflicts, thereby realizing the interweaving cooperative management of ground planning and on-orbit autonomous triggering tasks and having strong flexibility. The observation mode of the astronomical observation satellite has great reference significance for on-orbit autonomous management.

In summary, the above embodiments have described in detail different configurations of the on-orbit gamma ray exposure method, and it is understood that the present invention includes, but is not limited to, the configurations listed in the above embodiments, and any modifications based on the configurations provided by the above embodiments are within the scope of the present invention. One skilled in the art can take the contents of the above embodiments to take a counter-measure.

The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other. For the system disclosed by the embodiment, the description is relatively simple because the system corresponds to the method disclosed by the embodiment, and the relevant points can be referred to the method part for description.

The above description is only for the purpose of describing the preferred embodiments of the present invention, and is not intended to limit the scope of the present invention, and any variations and modifications made by those skilled in the art based on the above disclosure are within the scope of the appended claims.

Claims

1. An on-orbit gamma ray exposure opportunity target observation method for carrying out opportunity observation on a newly discovered source, a known transient source or a known transient source, which is characterized by comprising the following steps:

the observation task planning comprises:

2. The method of claim 1, wherein the frequency of multiple messenger opportunity observations is expected to be 1 time per week;

3. The method of on-orbit gamma ray riot opportunity target observation of claim 1, wherein the observation mission plan further comprises regular opportunity target observations and important opportunity target observations;

4. The on-orbit gamma ray riot opportunity target observation method of claim 3, wherein regular opportunity target observations are lower priority than gamma storm observations and recurring source observations and higher priority than regular observations, and the important opportunity target observations and the multi-messenger opportunity target observations are higher priority than gamma storm observations and recurring source observations;

the gamma storm observation includes:

5. The method of claim 3, wherein during normal operation of the astronomical observation satellite, the astronomical observation satellite performs normal opportunistic object observations once a day, the normal opportunistic object observations accounting for 15% of the total observation valid time;

6. The method of claim 3, wherein the expected frequency of significant opportunity target observations is 1 time per month.

7. The method of claim 3, wherein the on-orbit gamma ray exposure target observation orientation comprises: the included angle between the sun and the + Xs axis of the astronomical observation satellite is larger than 90 degrees, and the + X surface of the astronomical observation satellite is prevented from being irradiated by the sun;

8. The on-orbit gamma ray riot opportunity target observation method of claim 3, wherein the observation tasks of the conventional opportunity target observation include a conventional opportunity gamma ray revisit target task, a conventional opportunity complementary targeting target task, and a conventional opportunity celestial target task;

the high energy load remains in the current mode.

9. The on-orbit gamma ray riot opportunity target observation method of claim 3, wherein the important opportunity target observation comprises an immediate execution task and a delayed execution task, wherein:

the high energy load remains in the current mode;

10. The method of claim 3, wherein the observing of the on-board multi-messenger opportunity targets comprises the following steps:

when the front-sheet constraint is not passed, keeping the current task;

the high energy load remains in the current mode;