The approaches I was using are ones I understand. First with WWW::Mechanize, which I've used on that site for years. I haven't worked up the facility to do it with Mojo yet, despite many attempts. What happens is that I try to extend the script in a small way and can't quite get there. You said if I ran into the weeds again, let you know, so let's try this one, because it's where I was/am stuck with mojo.

I'm trying to enter the site at the beginning and mechanize my way through to the table I need after the initial sky map has been made. I tried commands like this to tell me something about the page:

$ mojo get https://www.fourmilab.ch/yoursky/ '*' attr id
skylat
skynsn
skynss
skylon
skyewe
skyeww
horlat
hornsn
hornss
horlon
horewe
horeww
feedback
$
[download]

I see 2 of the fields I need to populate here, but I don't know how to deal with the button in the mojo context. In your successful upthread script, you seem not to use a click_button event to get it done, so I tried to squeak by the same way:

$ ./3.mo_scrape.pl
./3.mo_scrape.pl 
45.5 -122.4 0.346 
Can't call method "children" on an undefined value at ./3.mo_scrape.pl
+ line 45.
$ cat 3.mo_scrape.pl
#!/usr/bin/env perl
use Mojo::UserAgent;
use 5.016;
use warnings;

use Mojo::UserAgent;
use DateTime::Format::Strptime;
use open ':std', OUT => ':utf8';
use Mojo::DOM;
use Log::Log4perl;

# get rid of old log
my $file = '/home/hogan/Documents/hogan/logs/4.log4perl.txt';
unlink $file or warn "Could not unlink $file: $!";
my $log_conf4 = "/home/hogan/Documents/hogan/logs/conf_files/4.conf";
Log::Log4perl::init($log_conf4);    #info
my $logger = Log::Log4perl->get_logger();
$logger->info("$0");

## important...no trailing zeroes else 301 error
my $lat  = 45.5;
my $long = -122.4;
my $elev = .346;                    #km
$logger->info("$lat $long $elev");
my $guess     = 2458960;            #Earth day 2020 in julian days
my $west_long = -$long;

# the API docs says you must identify yourself, please make this somet
+hing legit
# my $name = '(example.com, contact@example.com)';
#  can't I pretend to be a browser like any other?
my $uaname =
'Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like G
+ecko) Chrome/40.0.2214.93 Safari/537.36';
my $ua = Mojo::UserAgent->new;
$ua->transactor->name($uaname);

my $pturl = 'https://www.fourmilab.ch/yoursky/';

my $tx =
  $ua->post( $pturl => form => { skylat => $lat, skylon => $west_long 
+} );

$tx = $ua->post( $pturl => form => { utc => $guess, date => '2' } );
my $sunrow = $tx->res->dom->at('center:nth-of-type(3) table tr:n./2th-
+of-type(3)');

# output
say 'Name:' . $sunrow->children->[0]->all_text;
say 'Altitude: ' . $sunrow->children->[4]->text;
say 'Azimuth: ' . $sunrow->children->[5]->text;
say 'Visible: ' . $sunrow->children->[6]->text;
$
[download]

Q1) How do I lose this one? (I'd like to see the equivalent of $mech->uri) If I need the button it would have to look something like submit_button:

Q2) What gives with the %= symbol on the left?

I took Stellar Evolution my final semester in physics. I was doing alright until the final turned out to be a computer project that was to integrate a star given a certain composition (no idea what syntax). I was caught completely flatfooted and had somewhat of a meltdown, where I decided to continue my degree with mathematics instead. The failure has stung through the decades.

Copy that.

Q1: Tag helpers are convenient ways within Mojo tempaltes to generate HTML, e.g.

%= submit_button 'Ok!', id => 'foo'
[download]

Generates the HTML:

<input id="foo" type="submit" value="Ok!">
[download]

At this stage in your script I don't see anything for generating pages. Are you confusing this perhaps with submitting forms? In my example I just used the Mojo::UserAgent post method to submit the form. Basic investigation of the html shows what we need to submit to get the desired results.