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1
Open a Discussion / How does an SLR station affect the local bird population?
« Last post by Ole Klingan on September 27, 2021, 12:33:44 PM »
Hi everyone!

For the SLR station in Ny-Ålesund, Svalbard, we are trying to find out how an SLR station will affect the local bird polulation. The station is located nearby a bird nesting area.
So my question to the community is if anyone has ever put any attention into what happens to the local bird population over time, and if you ever have seen birds taking damage from the laser?

Best Regards

Ole
2
Data and Software Questions / COSPAR ID to ILRS format
« Last post by pywang on February 04, 2021, 03:14:50 PM »
Hello everybody,

Now I have a problem regarding converting COSPAR Int'l Code to ILRS format.
For a normal case it is easy, eg. "2009-005A" to “0900501”
But when having "2020-061AX", how then?
Second, is it correct that only 'O', ‘L’ and ‘I’ are omitted in COSPAR#, not more?

I put the discussing with Randy (I hope that is Okay for him) below, and there are some hits but not 100% solve my problem.

thanks in advance and best regards,
Wang Peiyuan




Quote
================================================================================
================================================================================
================================================================================
Hi Wang,

It's good to hear from you!

As you may know, the COSPAR ID to ILRS ID conversion algorithm is in the CRD and CPF manuals. I include it below. That explains the conversion, although there have been some exceptions over the years. The "i" is not used, as I understand it, because of its similar appearance to lower case "L" and the number "1". The letter "o" is apparently also not used because it looks like zero. Unfortunately, I don't have any source documentation on the COSPAR ID. I am cc-ing this message to Carey Noll and Julie Horvath, who have worked with the COSPAR ID more than I have.

As far as the debris data is concerned,  i.e., data that the ILRS analysts will never see, the ILRS ID could be set to "na" and the COSPAR ID could be included in a "00" comment record. You would still have the NORAD ID to identify the target, which should exist for all debris. (How much of the debris actually has a COSPAR ID? If stations are tracking rocket upper stages, farings, etc., do they have anything but a NORAD number?)

I am reluctant to say "use the COSPAR ID", because the ILRS ID is all numbers and the COSPAR-ID is numbers+letters+ "-". That could break current reading routines. The all-numeric solution you suggest might be a better idea, although that would have to be documented in the manual, too, and it is a bit clumsy. We could have a broader discussion in the DFPSG or the CB about changing the CRD manual so that the COSPAR ID could replace the ILRS ID for debris data only. You are right that this discussion would have been easier a year ago.  :-)

Take care,
Randy

COSPAR ID to ILRS Satellite Identification Algorithm:
COSPAR ID Format: (YYYY-XXXA)
YYYY is the four-digit year of when the launch vehicle was put in orbit
XXX is the sequential launch vehicle number for that year
A is the alpha numeric sequence number within a launch
Example: LAGEOS-1 COSPAR ID is 1976-039A
Explanation: LAGEOS-1 launch vehicle was placed in orbit in 1976; was the 39th launch in that year; and LAGEOS-1
was the first object injected into orbit from this launch.
ILRS Satellite Identification Format: (YYXXXAA), based on the COSPAR ID
YY is the two-digit year of when the launch vehicle was put in orbit
XXX is the sequential launch vehicle number for that year
AA is the numeric sequence number within a launch
Example: LAGEOS-1 ILRS Satellite ID is 7603901
-----------------------    Randy Ricklefs    ------------------------
                        ricklefs@csr.utexas.edu
      Center for Space Research,  The University of Texas at Austin
                            Austin TX 78712

________________________________________
From: WANG PEIYUAN <peiyuan.wang@oeaw.ac.at>
Sent: Friday, February 14, 2020 2:32 AM
To: Ricklefs, Randall L <ricklefs@csr.utexas.edu>
Subject: COSPAR ID convert to ILRS
 
Hello Randy,
 
 
Some question about COSPAR ID.
As you know LAGEOS-1 ILRS Satellite ID is 7603901 relating to COSPAR ID 1976-039A.
 
But how to convert targets ID like a decaded debris 1993-036ASU to ILRS ID, 93036011820 or something else?
,there A-01, S-18, U-20
Why S-18 not S-19? Because I found the letter “I” is not used in COSPAR ID
And I don’t know if any other letter also not used. :)
 
A example of S-NET serial, no “I” used.
43186 S-NET D  2018-014G
43187 S-NET B  2018-014H
43188 S-NET A  2018-014J
43189 S-NET C  2018-014K
 
I could not find the specification of COSPAR ID, and do you have it?
 
Do you see any chance that in CRD ver2, we just use COSPAR ID instead of ILRS format?  -- sorry a little too late.
 
Thanks in advance!!
3
In-Sky Safety / Re: Experience on Flightaware ProStick ADS-B receiver?
« Last post by Toshimichi Otsubo on July 01, 2020, 12:16:25 PM »
Moimoi Arttu,

I presented in Stuttgart last year what you have in mind. 

https://cddis.nasa.gov/2019_Technical_Workshop/docs/2019/presentations/Session5/session5_Otsubo_presentation.pdf

Toshi
4
In-Sky Safety / Re: Experience on Flightaware ProStick ADS-B receiver?
« Last post by jsteinborn on June 29, 2020, 11:10:08 AM »
Hi Arttu,

Radarcape can be used as drop-in replacement for SBS-3:

https://shop.jetvision.de

Jens
5
In-Sky Safety / Experience on Flightaware ProStick ADS-B receiver?
« Last post by ArttuR-H on June 18, 2020, 10:18:23 AM »
Hi all,
it seems that our Kinetic SBS-3 ADS-B receiver has died and I'm looking for a replacement. However, apparently those are not manufactured anymore.
But I found that Flightaware sells these very cheap usb-dongles for ADS-B monitoring with RaspberryPi, https://flightaware.com/adsb/prostick/ . Does anyone have any experience on these Flightaware Prostick & Prostick Plus models? Are they comparable to much more expensive receivers like Airnav radarbox (which we also have) or Kinetic SBS-3?
Best regards from Metsähovi,
Arttu
6
Data and Software Questions / Re: CPF Download from new https server
« Last post by Toshimichi Otsubo on February 06, 2020, 11:08:14 AM »
Hi Daniel and all,

I tried a different way - their "secondary" option ftp-ssl seemed easier in our environment.

Here is how I do using 'lftp' (command-line ftp client):

$ lftp -f cddis-cpf.lftp

where cddis-cpf.lftp (or any file name) is a text file like:
---
Code: [Select]
open -d -u anonymous,<YOUR EMAIL ADDRESS> -e 'set ftp:ssl-force true' gdc.cddis.eosdis.nasa.gov
set xfer:clobber true
cd /pub/slr/cpf_predicts/current
lcd <YOUR LOCAL DIRECTORY>
mirror -e -x MD5SUMS -x SHA512SUMS
exit
---

(Replace the two "< >" parts.)

Then, the local directory will contain the same files as the "/pub/slr/cpf_predicts/current" directory of CDDIS.  The lftp mirror downloads only newer files, so it will be quicker for the second time.

Toshi
7
Data and Software Questions / Software: CPF to Range+Az+El?
« Last post by Toshimichi Otsubo on February 01, 2020, 05:54:35 AM »
Are there any publicly available software that can produce the [Range, Az, El] time series from CPF for a given station position?  Toshi
8
Data and Software Questions / CPF Download from new https server
« Last post by danielhampf on January 16, 2020, 09:28:24 AM »
Hello all,
you've probably seen the emails about the NASA CPF server changing to https. I now adapted our python script in order to download the CPFs from that new server. I used the requests package rather than curl as I suggested by CDDIS examples. It's a bit tricky since they decided to use a login system which is not very suitable for automated download. Anyway, it works now. I post the code here for your convenience.
A few notes to the code. It's made to work with python3 and the python requests package installed. You need to obtain Earth Data login credentials first and then insert them here in the code (line ~37 / 38). The code will download the V1 CPFs, if you want the new ones, you have to change the target folder. Please note that the script will delete all existing files in the local target folder. If you use the function in a graphical interface, your callback function can update a progress bar etc. If it returns "false", the downloads will be cancelled. The function will return the number of downloaded CPFs.
The script is not entirely by me, it also uses code I found on the Earth Data site.
Comments and cheers welcome, as always.
Daniel




import os
from glob import glob
import requests

class SessionWithHeaderRedirection(requests.Session):
    AUTH_HOST = 'urs.earthdata.nasa.gov'
    def __init__(self, username, password):
        super().__init__()
        self.auth = (username, password)   
   
   # Overrides from the library to keep headers when redirected to or from
   # the NASA auth host.
    def rebuild_auth(self, prepared_request, response):
        headers = prepared_request.headers
        url = prepared_request.url
 
        if 'Authorization' in headers:
            original_parsed = requests.utils.urlparse(response.request.url)
            redirect_parsed = requests.utils.urlparse(url)
 
            if (original_parsed.hostname != redirect_parsed.hostname) and \
                    redirect_parsed.hostname != self.AUTH_HOST and \
                    original_parsed.hostname != self.AUTH_HOST:
                del headers['Authorization']
        return   
         
def download_CPFs_ssl(local_dir, update_callback):
    # remove old files
    if not os.path.isdir(local_dir):
        os.mkdir(local_dir)
    filelist = glob(os.path.join(local_dir, "*"))
    for f in filelist:
        os.remove(f)

    # define urls and credentials
    url = "https://cddis.nasa.gov/archive/slr/cpf_predicts/current/"
    username = ""
    password = ""

    # make the request to the web site to get filenames
    session = SessionWithHeaderRedirection(username, password)       
    response = session.get(url + "*?list")
   
    # check if response is okay
    if response.status_code is not requests.codes.ok:
        log.error("Could not connect to CPF server. HTML code: %d" % (response.status_code))
        return False   
   
    # parse the response and make list of filenames
    lines = response.text.split('\n')
    filenames = []
    for line in lines:
        if line.startswith("#"):    # comment lines
            continue
        if line.strip() == "":      # empty lines
            continue
        filename, size = line.split()
        filenames.append(filename)       

    # download each file and save it
    excl_list = ["MD5SUMS", "SHA512SUMS", "index.html"]
    for i, filename in enumerate(filenames):
        if filename in excl_list:
            continue
        filepath = url + filename
        response = session.post(filepath)
        with open(os.path.join(local_dir, filename), "wb") as f_out:
            f_out.write(response.content)
        keep_running = update_callback(100. * i / len(filenames))
        if not keep_running:
            break
    return i
       
       
       
if __name__ == "__main__":           
    def print_progress(p):
        print(p)
        return True
               
    download_CPFs_ssl("./CPF/", print_progress)
           
9
Station Equipment Questions / Re: Infrared thermal usb camera
« Last post by ewan.schafer on December 18, 2019, 01:00:51 PM »
Hi Matt,

Just want to echo what Johann said: the sensor seems nice but make sure you're getting one with a decent sized aperture to make sure you have enough sensitivity. Our camera can struggle distant aeroplanes when they're lower in the sky & under certain weather conditions.

This one seems like a nice model:
https://www.flir.co.uk/products/boson/?model=20640A006

But unfortunately, because they probably have to grow some kind of fancy crystal for the lens, I expect that the price is going to scale significantly with the amount of glass that you're buying.

Let me know how how it goes if you decide to get one, they could be interesting for us too!
10
Station Equipment Questions / Re: Infrared thermal usb camera
« Last post by Johann on December 06, 2019, 01:56:37 PM »
Hi Matt,

as you may already know, we bought our camera from InfraTec. I think the camera itself has almost the same specifications. However to increase the sensitifity we chose the greatest entrance lens that was available. In our case the lens diameter is 120 mm, while the field of view is 8 x 6 degree. I would not recommend to increase the field of view, because you are loosing sensitifity and resolution. We would prefer to have an even narrower field of view to reduce false alarm. But that is probably also depending on the applied object detection algorithm. Unfortunately i only know the price for the camera including the lens. It starts from ~29k, with some extras like low-noise-detector and increased resolution (1024x768) we ended up at almost 40k.
The cameras that you found look promising. With 60 Hz they provide an even higher frame rate. It would be nice to hear the price.

Best regards,
Johann
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