A method for loading and refreshing a telescope star map

Abstract

The present invention relates to the technical field of astronomical observation, and specifically provides a method for loading and refreshing a star map of a telescope. According to the station site of the telescope, stars that cannot be observed are eliminated to obtain all observable candidate stars, set screening conditions, select candidate stars to be observed that meet the screening conditions, establish multiple threads and sets corresponding to the multiple threads, evenly distribute the candidate stars to be observed to multiple sets, perform the first refresh of the observable candidate stars in the candidate stars to be observed through multiple threads, set multiple time slices, and distribute the candidate stars to be observed again, thereby realizing multi-threaded and batch real-time refresh of the candidate stars to be observed. The method for loading and refreshing the candidate stars provided by the present invention can greatly shorten the refresh time of the candidate stars, improve the refresh efficiency of the telescope's star map, and at the same time, there will be no jamming phenomenon in the batch refresh, making the refresh smoother and improving the user's experience of astronomical observation.

Description

Technical Field

[0001] The invention relates to the technical field of astronomical observation, and specifically provides a method for loading and refreshing a star map of a telescope. Background Art

[0002] Star tracking is one of the important functions of the horizontal telescope, which plays an important role in astronomical observation, pointing correction and astronomical positioning. The commonly used star pointing calculation tool is the SOFA (Standards of Fundamental Astronomy) code toolkit. The telescope control system inputs UTC time, station location and star information (right ascension, declination) to accurately calculate the position (azimuth, pitch) of the star at the station at that moment, thereby guiding the telescope to observe stars.

[0003] like Figure 1 Shown is a zenith chart commonly used in telescope control systems. The figure shows the state where star information has not been loaded yet. Directly above (north) is the azimuth of 0°, and the azimuth increases in a clockwise direction, ranging from 0° to 360°. The outermost circle is the minimum pitch value, i.e., 0° pitch, and the innermost circle is the maximum pitch value, i.e., 90° pitch.

[0004] like Figure 2 The figure shows the state of a station at a certain time after using the HIP catalog (Hipparcos Catalogues) to select stars within the observation range of the telescope from all stars below magnitude 8 and loading them into the zenith map.

[0005] for Figure 2 There are about 35,000 stars in the system. The traditional loading method is single-threaded loading. If single-threaded calculation is used, the time consumption of loading the system is as follows: if the CPU model of the application is Intel(R) Core(TM) i9-11900K @ 3.50GHz, the first loading takes 11.3s, and the average time consumption per star is 0.32ms; if the CPU model of the application is Intel(R) Core(TM) i7-6700HQ CPU @ 2.60GHz, the first loading takes 42s, and the average time consumption per star is 1.2ms.

[0006] The existing technology uses a single thread to calculate the star map, and it takes a long time to load the star map for the first time. In addition, since the overall star loading time is too long, the star map cannot be refreshed in real time after loading. Summary of the invention

[0007] In order to solve the above problems, the present invention provides a telescope star map loading and refreshing method, which adopts multi-threading to refresh candidate stars in batches, shortens the telescope star map refresh time, improves the refresh efficiency, and enhances the user experience.

[0008] The telescope star map loading and refreshing method provided by the present invention comprises:

[0009] S1: Based on the address of the telescope observation station, obtain all the stars that the telescope can observe within 24 hours as candidate stars, and collect the candidate stars Load it into the telescope control system to complete the loading of candidate stars;

[0010] S2: Preset screening conditions to filter candidate star sets The candidate stars that meet the screening conditions are called the set of stars to be observed. ;

[0011] S3: Calculate the set of stars to be observed The pitch angles of all candidate stars at the current moment in the set. If the pitch angle is greater than 0°, the candidate star is called an observable candidate star. Displayed in the telescope's star map, completing the first refresh of the telescope's star map;

[0012] S4: Refresh the telescope star map in real time:

[0013] S41: Division Time slices, create star information collection, and create Threads ,in, The value should not be greater than the number of CPU cores of the telescope control system. Indicates the thread sequence number, ;

[0014] S42: Assemble the stars to be observed The star information in is assigned to From the star information set, multiple subsets are obtained ,in Represents the sequence number of any time slice, ; Subset Assign to thread middle;

[0015] S43: By Thread Calculating Subsets The azimuth and elevation angles of all candidate stars to be observed at the current moment;

[0016] S44: Based on the azimuth and elevation angles of all candidate stars to be observed at the previous moment and the current moment, the following judgment is made:

[0017] If the pitch angle of the candidate star to be observed changes from less than or equal to 0° to greater than 0°, it is considered that the candidate star to be observed has become observable at the current moment and is moved into the observable candidate star set and displayed in telescopic star maps;

[0018] If the pitch angle of the candidate star to be observed changes from greater than 0° to less than or equal to 0°, it is considered that the candidate star to be observed has become unobservable at the current moment and is removed from the observable candidate star set. Removed;

[0019] If the pitch angle of the candidate star to be observed is continuously greater than 0°, it is considered that the candidate star to be observed is continuously observable at the current moment. In the above method, the position information of the candidate star to be observed is updated;

[0020] The observable candidate star collection Shown in telescopic star maps;

[0021] Update the time slice number to ,like ,but , repeat S43 to S44.

[0022] Preferably, the candidate stars are all stars recorded in the Hipparcos catalog.

[0023] Preferably, the method for obtaining candidate stars is:

[0024] The following judgment is made based on the latitude value of the telescope observation station address:

[0025] If the latitude value is within the range of [-1°,1°], all stars are candidate stars;

[0026] If the latitude value is greater than 1°, calculate the declination value corresponding to an azimuth of 180° and an elevation of 0° , then the declination value is [ ,90°] are all candidate stars;

[0027] If the latitude value is less than -1°, calculate the declination value corresponding to an azimuth of 0° and an elevation of 0° , then the declination value is [-90°, ] are all candidate stars.

[0028] Preferably, the sieve uses the basic astronomy standard code toolkit to calculate the declination value and declination values .

[0029] Preferably, the screening conditions include the magnitude range of the candidate stars and the spectral type of the candidate stars.

[0030] Preferably, a set of candidate stars can be observed The display method is:

[0031] Q1: Create The star collection and A one-to-one correspondence between the star set Computation threads ,in Indicates the thread sequence number, ;

[0032] Q2: Assign all observable candidate stars to In a collection of stars;

[0033] Q3: Calculate the pitch angles of all observable candidate stars in the star set corresponding to each thread at the current moment;

[0034] Q4: A collection of all observable candidate stars with elevation angles greater than 0° Send to telescope for display in star map.

[0035] Preferably, the number of time slices The value is 8.

[0036] Compared with the prior art, the present invention can achieve the following beneficial effects:

[0037] When loading the telescope star map, the embodiment of the present invention directly removes the stars that can never be observed. For the telescope observation station sites at most latitudes, the total number of stars involved in the calculation decreases, and the higher the latitude, the smaller the total number. The number of stars that need to be loaded and refreshed is greatly reduced, which reduces the amount of calculation for the subsequent first refresh and implementation of the refresh star map, and improves the refresh efficiency.

[0038] Before refreshing the telescope star map for the first time, candidate stars to be observed are selected according to screening conditions, which can further reduce the number of stars to be refreshed. When refreshing the telescope star map for the first time, the embodiment of the present invention takes advantage of the parallel acceleration of multi-core processors to distribute the observable candidate stars to be refreshed to multiple threads for refreshing, which greatly reduces the time consumption of star calculation and shortens the first refresh time. The more CPU cores the telescope control system has, the greater the reduction in time consumption.

[0039] When refreshing the star map in real time, the time-slicing and multi-threading method is used to recalculate the position of each group of stars to be observed in its fixed time slice and thread, ultimately achieving the purpose of small-batch, time-sharing, and continuous position update of stars. This not only ensures the accuracy of the star positions in the star map, but also further shortens the time for real-time refreshing of the telescope star map and improves the refresh efficiency.

[0040] In addition, the present invention sets a real-time refresh method for time-slice refresh, which can reduce the refresh freeze phenomenon, making the real-time refresh of the telescope star map smoother, and improving the user's experience of astronomical observation. The higher the CPU main frequency of the telescope control system and the more cores it has, the smoother the real-time refresh and the better the user experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 is a telescope zenith map without candidate stars loaded according to an embodiment of the present invention;

[0042] Figure 2 is a telescope zenith image after loading observable candidate stars provided by an embodiment of the present invention;

[0043] Figure 3 is a flow chart of loading and refreshing a telescope star map according to an embodiment of the present invention;

[0044] Figure 4 is a flow chart of an alternative star acquisition method provided according to an embodiment of the present invention;

[0045] Figure 5 is a flow chart of a method for refreshing a telescope star map for the first time according to an embodiment of the present invention;

[0046] Figure 6 It is a flow chart of a method for real-time refreshing of a telescope star map provided according to an embodiment of the present invention. DETAILED DESCRIPTION

[0047] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the following description, the same modules are represented by the same reference numerals. In the case of the same reference numerals, their names and functions are also the same. Therefore, the detailed description thereof will not be repeated.

[0048] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and do not constitute a limitation of the present invention.

[0049] like Figure 3 As shown, an embodiment of the present invention provides a method for loading and refreshing a telescope star map, comprising:

[0050] S1: When using a telescope for astronomical observation, after the telescope is turned on for the first time and the star observation software is opened, it is necessary to load the observable stars first. From the observation point of view, the change of the star's position relative to the ground observation position is mainly caused by the rotation of the earth, and the star itself can be considered to be motionless for a long time. When the observer is located at the equator, all stars can be observed in theory within one day. When the observer is located in the northern hemisphere, all stars in the northern hemisphere sky area can be observed in theory within one day, and the stars in some areas of the southern hemisphere are always blocked by the earth and cannot be observed. When the observer is located in the southern hemisphere, all stars in the southern hemisphere sky area can be observed in theory within one day, and the stars in some areas of the northern hemisphere are always blocked by the earth and cannot be observed. Therefore, when a telescope observation station is located, the stars that can never be observed can be excluded according to the latitude of the station, leaving the stars that can appear in the observation range within 24 hours as candidate stars. For different stations, the number of candidate stars is not necessarily the same. There are fewer candidate stars in high latitudes and more candidate stars in low latitudes.

[0051] According to the address of the telescope observation station, the SOFA (Standards of Fundamental Astronomy) code toolkit is applied, and the stars recorded in the HIP catalog (Hipparcos Catalogues) are used as the range. All the stars included in the Hipparcos catalog that can be observed by the telescope within 24 hours are obtained as candidate stars to obtain the candidate star set. , load the above candidate stars into the telescope's control system, and complete the loading of candidate stars when the telescope is turned on. Figure 4 As shown, the method for obtaining candidate stars is as follows:

[0052] The following judgment is made based on the latitude value of the telescope observation station address:

[0053] If the latitude of the telescope station is between [-1°, 1°], the telescope station is considered to be located near the Earth's equator, and all stars can be observed at some time within 24 hours, that is, all stars in the Hipparcos catalog are candidate stars;

[0054] If the latitude of the telescope observation station is greater than 1°, that is, greater than 1° north latitude, the declination value corresponding to the calculated azimuth angle of 180° and the pitch angle of 0° is expressed as , then in the Hipparcos catalog, the declination value is [ ,90°] are all candidate stars;

[0055] If the latitude of the telescope observation station is less than -1°, that is, greater than 1° south latitude, the declination value corresponding to the azimuth angle of 0° and the elevation angle of 0° is calculated. , then in the Hipparcos catalog, the declination value is [-90°, ] are all candidate stars.

[0056] Among them, the Hipparcos Star Catalog (HIP) is the main achievement of the European Space Agency (ESA) Hipparcos Astrometry Satellite (Hipparcos) program. The HIP star catalog contains a large amount of high-precision celestial position and photometric data, which can be used as the data basis for telescope astronomical observations and is an open database on the Internet. The basic astronomy standard SOFA code toolkit was created by the International Astronomical Union (IAU). The SOFA code toolkit is a collection of subroutines that implement the official IAU algorithms for basic astronomical calculations, provide authoritative and effective algorithm programs and constant values ​​for astronomical calculations, and are open source C language codes. The above two concepts are basic concepts in the field of astronomical observation and belong to the prior art.

[0057] S2: The candidate star set obtained above All the candidate stars are observable by the telescope at a certain moment within 24 hours, but not at all times within 24 hours. Therefore, the telescope's star map will not show all the candidate stars at every moment, and the telescope star map needs to be refreshed according to the observability of the candidate stars.

[0058] like Figure 5 As shown, the method for refreshing the telescope star map for the first time is as follows:

[0059] The user sets candidate star screening conditions according to the situation of the stars to be observed, and selects all candidate stars that meet the screening conditions from the candidate stars. In the embodiment of the present invention, they are referred to as candidate stars to be observed, and a set of candidate stars to be observed is obtained. The screening condition mentioned in the embodiment of the present invention refers to the star condition that the inventor needs to observe, such as the candidate star magnitude, the candidate star spectral range and the candidate star number. The embodiment of the present invention takes the magnitude as an example. Assuming that the user needs to observe candidate stars with a magnitude lower than 8, the screening condition is that the star magnitude is lower than 8. When the telescope star map is refreshed, only the candidate stars with a magnitude lower than 8 are refreshed to the telescope star map, which is about 35,000.

[0060] S3: Calculate the set of stars to be observed The pitch angles of all candidate stars at the current moment. If the pitch angle is greater than 0°, it means that the candidate star can be observed at the telescope observation station at the current moment. The candidate star to be observed is called an observable candidate star. All observable candidate stars form an observable candidate star set. , the observable candidate star set Displayed in the telescope's star map, completing the first refresh of the telescope's star map.

[0061] The above observable candidate star set The display method is as follows:

[0062] Q1: First, query the number of CPU (Central Processing Unit) cores of the computer used by the telescope control system, and create The star collection and A one-to-one correspondence between the star set Computation threads ,in Indicates the thread sequence number, , The value should not be greater than the number of CPU cores;

[0063] Q2: Collect observable candidate stars All observable candidate star information is evenly distributed to From the star set, we get the sub-set ;

[0064] Q3: Apply the basic astronomy standard code toolkit to calculate each thread The corresponding observable star set The azimuth and elevation angles of all observable candidate stars at the current moment;

[0065] Q4: Determine whether the pitch angle obtained by the above calculation is greater than 0°. If the pitch angle is greater than 0°, it is considered that the telescope can observe the observable candidate star. All observable candidate stars with pitch angles greater than 0° are merged to form an observable candidate star set. , the observable candidate star set Send it to the telescope star map for display, realizing the first refresh of the telescope star map.

[0066] When the above method is used to refresh the telescope star map for the first time, when the aforementioned CPU model is Intel(R)Core(TM) i9-11900K @ 3.50GHz (16 cores), 16 threads are used for parallel computing, and the time consumption is reduced to 1.2s, a reduction of 89%; when the aforementioned CPU model is Intel(R) Core(TM) i7-6700HQ CPU @ 2.60GHz (8 cores), 8 threads are used for parallel computing, and the time consumption is reduced to 9.8s, a reduction of 77%, and the efficiency improvement effect is obvious.

[0067] S4: Since the earth is constantly rotating, the positions of candidate stars to be observed change in real time relative to the observing telescope. Some observable candidate stars may be blocked by the earth after a period of observation and cannot be observed any further, or candidate stars to be observed that were originally blocked by the earth and cannot be observed become observable. Even the positions of candidate stars that are continuously observable may change, so it is necessary to refresh the telescope star map in real time.

[0068] like Figure 6 As shown, the method for real-time refreshing of the telescope star map is as follows:

[0069] S41: Division time slices and create A set of star information, among which, The value should not be greater than the number of CPU cores. Indicates the number of time slices. In the embodiment of the present invention, the number of time slices The value is 8, and 8 time slices can be understood as batches of 8 sequences. The star information set can be recreated, or the one created in step Q1 above can be The star collection is then split into A collection of star information, A collection of star information. Since the telescope star map is refreshed only once for the first time, the Each star set is used only once and can be reused after the first refresh.

[0070] create Threads ,in, The value should not be greater than the number of CPU cores of the telescope control system. Indicates the thread sequence number, , the number of threads and the number of star information sets One-to-one correspondence, that is, each thread corresponds A collection of star information. The thread can be created from scratch or directly applied in Q3. The telescope star map is refreshed only once for the first time, so it is created in Q3. Each computation thread is used only once and can be reused after the first refresh.

[0071] S42: The embodiment of the present invention is used Represents the sequence number of any time slice, , the set of candidate stars to be observed All the star information in is evenly distributed to From the star information set, multiple subsets are obtained , the subset Assigned to the thread In, that is, thread Corresponding sub-set .

[0072] S43: By Thread Calculating Subsets The azimuth and elevation angles of all candidate stars to be observed at the current moment. It can realize the calculation of azimuth and elevation angles by dividing multiple candidate stars to be observed into multiple groups and batches, which reduces the calculation time and improves the calculation efficiency.

[0073] S44: Combine the azimuth and elevation angles of all candidate stars to be observed at the previous moment, compare and make the following judgment:

[0074] When transitioning from the previous moment to the current moment, if the pitch angle of the candidate star to be observed changes from less than or equal to 0° to greater than 0°, the candidate star to be observed changes from being blocked by the earth to being not blocked by the earth. It is considered that the candidate star to be observed becomes observable at the current moment and is moved into the observable candidate star set. middle;

[0075] When transitioning from the previous moment to the current moment, if the pitch angle of the candidate star to be observed changes from greater than 0° to less than or equal to 0°, the candidate star to be observed changes from a state of not being blocked by the earth to a state of being blocked by the earth. It is considered that the candidate star to be observed has become unobservable at the current moment, and the observable candidate star set is Removed;

[0076] When transitioning from the previous moment to the current moment, if the pitch angle of the candidate star to be observed is continuously greater than 0°, then the candidate star to be observed is continuously not blocked by the earth, and it is considered that the candidate star is continuously observable at the current moment. In the above method, the position information of the candidate star to be observed is updated;

[0077] The observable candidate star collection Shown in telescopic star charts.

[0078] It should be noted that after the position information of the stars to be observed contained in each time slice is calculated, it is refreshed uniformly, so the number of divided time slices is the number of refreshes.

[0079] If the pitch angle of the candidate star to be observed is continuously less than or equal to 0°, it means that the candidate star to be observed is continuously blocked by the earth and is continuously unobservable, and there is no need to refresh it.

[0080] Update the time slice number to , repeat S43 to S44 for the time slice, and refresh the telescope star map corresponding to the next time slice. Complete the batch and multi-thread real-time refresh of the telescope star map. If there is a , then the subsets corresponding to all time slices are All candidate stars to be observed in the real-time refresh are completed once, and then all candidate stars to be observed are refreshed again in real time, that is, , restart the next round of real-time refresh.

[0081] Although the embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and cannot be understood as limiting the present invention. Those skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

[0082] The above specific implementations of the present invention do not constitute a limitation on the protection scope of the present invention. Any other corresponding changes and modifications made based on the technical concept of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A method for loading and refreshing a telescope star map, characterized in that: include: S1: According to the address of the telescope observation station, all stars that can be observed by the telescope within 24 hours are obtained as candidate stars, and the candidate stars are collected Load it into the telescope control system to complete the loading of candidate stars; S2: Preset screening conditions to screen the candidate star set The candidate stars that meet the above screening conditions are called the set of stars to be observed ; S3: Calculate the set of stars to be observed The pitch angles of all candidate stars at the current moment in the set. If the pitch angle is greater than 0°, the candidate star is called an observable candidate star. Displayed in the star map of the telescope, completing the first refresh of the telescope star map; S4: Refresh the telescope star map in real time: S41: Division Time slices, create star information collection, and create Threads ,in, The value should not be greater than the number of CPU cores of the telescope control system. Indicates the thread sequence number, ; S42: Assemble the stars to be observed The star information in is assigned to From the star information set, multiple subsets are obtained ,in Represents the sequence number of any time slice, ; The subset Assigned to the thread middle; S43: By Thread Calculating Subsets The azimuth and elevation angles of all candidate stars to be observed at the current moment; S44: Based on the azimuth and elevation angles of all candidate stars to be observed at the previous moment and the current moment, the following judgment is made: If the pitch angle of the candidate star to be observed changes from less than or equal to 0° to greater than 0°, it is considered that the candidate star to be observed has become observable at the current moment, and it is moved into the observable candidate star set middle; If the pitch angle of the candidate star to be observed changes from greater than 0° to less than or equal to 0°, it is considered that the candidate star to be observed has become unobservable at the current moment, and it is removed from the observable candidate star set. Removed; If the pitch angle of the candidate star to be observed is continuously greater than 0°, it is considered that the candidate star to be observed is continuously observable at the current moment, and is included in the observable candidate star set. In the above method, the position information of the candidate star to be observed is updated; The observable candidate star collection shown in said telescopic star map; Update the time slice number to ,like ,but , repeat S43 to S44.

2. The telescope star map loading and refreshing method according to claim 1, characterized in that: The candidate stars are all stars recorded in the Hipparcos catalog.

3. The telescope star map loading and refreshing method according to claim 1, characterized in that: The method for obtaining the candidate stars is as follows: The following judgment is made based on the latitude value of the telescope observation station address: If the latitude value is within the range of [-1°, 1°], all stars are candidate stars; If the latitude value is greater than 1°, calculate the declination value corresponding to an azimuth of 180° and an elevation of 0° , then the declination value is [ ,90°] are all candidate stars; If the latitude value is less than -1°, calculate the declination value corresponding to an azimuth of 0° and an elevation of 0° , then the declination value is [-90°, ] are all candidate stars.

4. The telescope star map loading and refreshing method according to claim 3, characterized in that: The declination values ​​are calculated using the Basic Astronomy Standard Code Toolkit and declination values .

5. The telescope star map loading and refreshing method according to claim 1, characterized in that: The screening conditions include the magnitude range of the candidate stars and the spectral type of the candidate stars.

6. The telescope star map loading and refreshing method according to claim 1, characterized in that: The observable candidate star set The display method is: Q1: Create The star collection and A one-to-one correspondence between the star sets Computation threads ,in Indicates the thread sequence number, ; Q2: Assign all observable candidate stars to the In a collection of stars; Q3: Calculate the pitch angles of all observable candidate stars in the star set corresponding to each thread at the current moment; Q4: A collection of all observable candidate stars with elevation angles greater than 0° Send to telescope for display in star map.

7. The telescope star map loading and refreshing method according to claim 1, characterized in that: The number of time slices The value is 8.

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