In depth analysis of Python how to make a real-time tracker for the International Space Station

1, Foreword

  • Open Notify is an open source project designed to provide a simple programming interface for some of NASA's outstanding data.
  • The authors of open-notify.org did some work to obtain raw data and convert it into API s related to space and spacecraft.
  • Now through this interface, we will get the location of the international space station and draw it on the map in real time.
  • In order to achieve this goal, ISS must be installed first_ Info:
pip install ISS-Info

2, Map initialization

  • In order to show the path of the international space station in real time, a curve needs to be drawn by using turtle, so you can create a turtle canvas and set the background as earth:
import ISS_Info
import turtle
import time
import json
import urllib.request
screen = turtle.Screen()
screen.setup(720, 360)
screen.setworldcoordinates(-180, -90, 180,90)
screen.bgpic("map.png")
screen.bgcolor("black") 
screen.register_shape("isss.gif")
screen.title("Real time ISS tracker")
iss = turtle.Turtle()
iss.shape("isss.gif") 
  • The effects are as follows:

3, Get the number of people on the space station

  • If we can know the number of astronauts on the space station, we can track the international space station more accurately. Fortunately, open notify does provide such an interface.
  • In order to obtain the number of people information, you must request the data from the following interfaces and write the corresponding astronaut's name in the upper left corner:
http://api.open-notify.org/astros.json
  • Implementation code:
astronauts = turtle.Turtle()
astronauts.penup()
astronauts.color('black')
astronauts.goto(-178,86)
astronauts.hideturtle()
url = "http://api.open-notify.org/astros.json"
response = urllib.request.urlopen(url)
result = json.loads(response read())
print("There are currently " + str(result ["number"]) + " astronauts in space:")
print("")
astronauts.write("People in space: " + str(result["number"]), font=style)
astronauts.sety(astronauts.ycor() - 5)

people = result["people"] 

for p in people:
	print(p["name"] + " on: " + p["craft"])
	astronauts.write(p["name" ] + "on:" + p["craft"], font=style)
	astronauts.sety(astronauts.ycor() - 5)
  • The effects are as follows:

4, Draw station location

  • In order to draw the real-time position of the space station, it is necessary to request the position information of the space station. The requested interface is:
http://api.open-notify.org/iss-now.json
  • However, the author encapsulates it into a function, and we call ISS directly_ current_ LOC to obtain the location of the international space station:
while True :
	location = ISS_Info.iss_current_loc()
	lat = location['iss_ position']['latitude']
	lon = location['iss_ position']['longitude']
	print("Position: \n latitude: {}, longitude: {}" .format(lat, lon))
	pos = iss.pos()
	posx = iss.xcor()
	if iss.xcor() >= (179.1): 			 ### Stop drawing at the right edge of
		iss.penup() 			         ### the screen to avoid a
		iss.goto(float(lon), float(lat)) ### horizontal wrap round line 
		time.sleep(5)
	else:
		iss.goto(float(lon), float(lat))
		iss.pendown()
		time.sleep(5)
  • We can also mark our current position to see the distance from the international space station and the point in time (UTC) when the space station passes over you.
# Shenzhen
lat = 112.5118928
lon = 23.8534489
prediction = turtle.Turtle()
prediction.penup()
prediction.color('yellow') 
prediction.goto(lat, lon)
prediction.dot(5)
prediction.hideturtle()
url = 'http://api.open-notify.org/iss-pass.json?lat=' + str(lat-90) + '&lon=' + str(lon)
response = urllib.request.urlopen(url)
result = json.loads(response.read())
over = result ['response'][1]['risetime']
prediction.write(time.ctime(over), font=style)
  • However, it is worth noting that the latitude calculation of iss-pass.json interface must be within - 90 to 90, so the latitude of Shenzhen needs to be subtracted by 90.
  • The final effect is as follows:

Posted on Sun, 10 Oct 2021 03:04:07 -0400 by haolan