Assigning satellite data to geo-locations¶
Example: Tracking the International Space Station with Dask¶
In this notebook we will use two APIs:
We will use them to track ISS location and next transit time with respect to a list of cities. To create our charts and parallelise data intelligently, we will use Dask, specifically Dask Delayed.
1. Imports¶
[1]:
import logging
import sys
from datetime import datetime
from math import radians
from operator import itemgetter
from time import sleep
import numpy as np
import requests
from dask import delayed
from sklearn.metrics import DistanceMetric
2. Logger¶
[2]:
logger = logging.getLogger()
logger.setLevel(logging.INFO)
3. Latitude and longitude pairs from a list of cities¶
[3]:
from geopy.geocoders import Nominatim
def get_lat_long(address):
loc = Nominatim(user_agent="Geopy Library")
getLoc = loc.geocode(address)
return {
"name": getLoc.address,
"lat": getLoc.latitude,
"long": getLoc.longitude
}
[4]:
get_lat_long("Berlin, Germany")
[4]:
{'name': 'Berlin, Deutschland', 'lat': 52.510885, 'long': 13.3989367}
[5]:
locations = []
for city in [
"Seattle, Washington",
"Miami, Florida",
"Berlin, Germany",
"Singapore",
"Wellington, New Zealand",
"Beirut, Lebanon",
"Beijing, China",
"Nairobi, Kenya",
"Cape Town, South Africa",
"Buenos Aires, Argentina",
]:
locations.append(get_lat_long(city))
sleep(2)
[6]:
locations
[6]:
[{'name': 'Seattle, King County, Washington, United States',
'lat': 47.6038321,
'long': -122.330062},
{'name': 'Miami, Miami-Dade County, Florida, United States',
'lat': 25.7741728,
'long': -80.19362},
{'name': 'Berlin, Deutschland', 'lat': 52.510885, 'long': 13.3989367},
{'name': 'Singapore', 'lat': 1.357107, 'long': 103.8194992},
{'name': 'Wellington, Wellington City, Wellington, 6011, New Zealand / Aotearoa',
'lat': -41.2887953,
'long': 174.7772114},
{'name': 'بيروت, البسطة التحتا, باشورة, محافظة بيروت, لبنان',
'lat': 33.88922645,
'long': 35.50255852895232},
{'name': '北京市, 中国', 'lat': 40.190632, 'long': 116.412144},
{'name': 'Nairobi, Kenya',
'lat': -1.3026148499999999,
'long': 36.82884201813725},
{'name': 'Cape Town, City of Cape Town, Western Cape, 8001, South Africa',
'lat': -33.9288301,
'long': 18.4172197},
{'name': 'Buenos Aires, Comuna 6, Ciudad Autónoma de Buenos Aires, Argentina',
'lat': -34.6083696,
'long': -58.4440583}]
4. Retrieve ISS data and determine transit times of cities¶
[7]:
def get_spaceship_location():
resp = requests.get("http://api.open-notify.org/iss-now.json")
location = resp.json()["iss_position"]
return {
"lat": float(location.get("latitude")),
"long": float(location.get("longitude")),
}
[8]:
def great_circle_dist(lon1, lat1, lon2, lat2):
dist = DistanceMetric.get_metric("haversine")
lon1, lat1, lon2, lat2 = map(np.radians, [lon1, lat1, lon2, lat2])
X = [[lat1, lon1], [lat2, lon2]]
kms = 6367
return (kms * dist.pairwise(X)).max()
[9]:
def iss_dist_from_loc(issloc, loc):
distance = great_circle_dist(
issloc.get("long"), issloc.get("lat"), loc.get("long"), loc.get("lat")
)
logging.info(f"ISS is {int(distance)}km from {loc.get("name")}")
return distance
[10]:
def iss_pass_near_loc(loc):
resp = requests.get(
"http://api.open-notify.org/iss-pass.json",
params={"lat": loc.get("lat"), "lon": loc.get("long")},
)
data = resp.json().get("response")[0]
td = datetime.fromtimestamp(data.get("risetime")) - datetime.now()
m, s = divmod(int(td.total_seconds()), 60)
h, m = divmod(m, 60)
logging.info(
"ISS will pass near %s in %02d:%02d:%02d", loc.get("name"), h, m, s
)
return td.total_seconds()
The predictions for the iss-pass
API are unfortunately no longer available, seeOpen Notify API Server.
[11]:
iss_dist_from_loc(get_spaceship_location(), locations[2])
INFO:root:ISS is 3057km from Berlin, Deutschland
[11]:
np.float64(3057.10849285221)
[12]:
iss_pass_near_loc(locations[2])
INFO:root:ISS will pass near Berlin, 10117, Germany in 00:25:14
[12]:
1514.253889
5. Creating a delayed
pipeline¶
[13]:
output = []
for loc in locations:
issloc = delayed(get_spaceship_location)()
dist = delayed(iss_dist_from_loc)(issloc, loc)
output.append((loc.get("name"), dist))
closest = delayed(lambda x: sorted(x, key=itemgetter(1))[0])(output)
[14]:
closest
[14]:
Delayed('lambda-5ab5a78f-cb72-4168-bce1-f9983fdb8a2e')
6. Show DAG¶
[15]:
closest.visualize()
[15]:

7. compute()
¶
[16]:
closest.compute()
INFO:root:ISS is ~4685km from Miami, Miami-Dade County, Florida, USA
INFO:root:ISS is ~15205km from Beirut, Beirut Governorate, Lebanon
INFO:root:ISS is ~5919km from Seattle, King County, Washington, USA
INFO:root:ISS is ~6279km from Autonomous City of Buenos Aires, Comuna 6, Autonomous City of Buenos Aires, Argentina
INFO:root:ISS is ~12625km from Berlin, 10117, Germany
INFO:root:ISS is ~13137km from Cape Town, City of Cape Town, Western Cape, 8001, South Africa
INFO:root:ISS is ~16194km from Singapore
INFO:root:ISS is ~16298km from Nairobi, Kenya
INFO:root:ISS is ~13905km from Beijing, Dongcheng District, Beijing, 100010, China
INFO:root:ISS is ~8405km from Wellington, Wellington City, Wellington, 6011, New Zealand
[16]:
('Miami, Miami-Dade County, Florida, USA', 4685.887400314564)