Scraping the Open Directory with Python

From the dmoz website:

DMOZ is the largest, most comprehensive human-edited directory of the Web. It is constructed and maintained by a passionate, global community of volunteers editors. It was historically known as the Open Directory Project (ODP).

Step 1: Extracting the links from a particular directory page

Let's start at a single page on dmoz, such as:

http://www.dmoz.org/Science/Astronomy/

If you look into the source, we can see the structure around the URLs listed at the bottom of the page:

<ul style="margin-left:0;" class="directory-url">
<li>
<a class="listinglink" href="http://www.absoluteastronomy.com/">Absolute Astronomy</a> 
- Facts and statistical information about planets, moons, constellations, stars, galaxies, and Messier objects.
<div class="flag"><a href="/public/flag?cat=Science%2FAstronomy&amp;url=http%3A%2F%2Fwww.absoluteastronomy.com%2F"><img title="report an issue with this listing" alt="[!]" src="/img/flag.png"></a></div>
</li>

import urllib2, html5lib, sys

url = sys.argv[1]

f = urllib2.urlopen(url)
src = f.read()
tree = html5lib.parse(src, namespaceHTMLElements=False)

for div in tree.findall(".//ul"):
    if "directory-url" in div.get("class", "").split():
        for li in div.findall("li"):
            for a in li.findall("a"):
                if "listinglink" in a.get("class", "").split():
                    linkurl = a.get("href")
                    linkdescription = a.tail.strip().strip("-").strip()
                    print (linkurl)
                    print ("\t"+linkdescription.encode("utf-8"))
                    print ()

Step 2: Following links of related categories

The pages also contain links to sub- and related categories, if we want to follow these as well, we can...

Conceptually, we add a notion of a "to do" list, for URLs we still want to check, and then a "seen" list for remembering where we've already been. The seen list is actually more efficient to implement as a python dictionary where we "add" a URL by using the URL as a key value which points to True (it doesn't actually matter what value is assigned in the example).

<div class="dir-1 borN">
    <span><img style="height:2px;float:left;width:100%" src="http://o.aolcdn.com/os/dmoz/img/dividerN.gif"></span>
    <ul class="directory dir-col">
        <li class="">
            <a href="/Science/Anomalies_and_Alternative_Science/Astronomy%2C_Alternative/">Alternative</a>@ 
            <em>(72)</em>
        </li>

from __future__ import print_function
import urllib2, html5lib, sys
from urlparse import urljoin

url = sys.argv[1]

todo = [url]
seen = {}

while len(todo) > 0:
    url, todo = todo[0], todo[1:]
    if url not in seen:
        f = urllib2.urlopen(url)
        print("VISITING", url)
        seen[url] = True
        src = f.read()
        tree = html5lib.parse(src, namespaceHTMLElements=False)

        # Extract links
        print ("LINKS")
        for div in tree.findall(".//ul"):
            if "directory-url" in div.get("class", "").split():
                for li in div.findall("li"):
                    for a in li.findall("a"):
                        if "listinglink" in a.get("class", "").split():
                            linkurl = a.get("href")
                            linkdescription = a.tail.strip().strip("-").strip()
                            print (linkurl)
                            print ("\t"+linkdescription.encode("utf-8"))

        # Follow the related category pages
        print ("RELATED")
        for div in tree.findall(".//ul"):
            if "directory" in div.get("class", "").split():
                for li in div.findall("li"):
                    for a in li.findall("a"):
                        suburl = a.get("href")
                        suburl = urljoin(url, suburl)
                        description = a.text.strip()
                        print (suburl)
                        print ("\t"+description.encode("utf-8"))
                        if suburl not in seen:
                            todo.append(suburl)

        print ()

Step 3: Putting it all together

from __future__ import print_function
import urllib2, html5lib, sys
from urlparse import urljoin


url = sys.argv[1]

todo = [url]
seen = {}
links = {}

while len(todo) > 0:
    url, todo = todo[0], todo[1:]
    if url not in seen:
        f = urllib2.urlopen(url)
        print("VISITING", url)
        seen[url] = True
        src = f.read()
        tree = html5lib.parse(src, namespaceHTMLElements=False)

        # Extract links
        for div in tree.findall(".//ul"):
            if "directory-url" in div.get("class", "").split():
                for li in div.findall("li"):
                    for a in li.findall("a"):
                        if "listinglink" in a.get("class", "").split():
                            linkurl = a.get("href")
                            linkdescription = a.tail.strip().strip("-").strip()
                            if linkurl in links:
                                print ("already seen", linkurl)

                            # Record the link
                            links[linkurl] = linkdescription

        # Follow the related category pages
        for div in tree.findall(".//ul"):
            if "directory" in div.get("class", "").split():
                for li in div.findall("li"):
                    for a in li.findall("a"):
                        suburl = a.get("href")
                        suburl = urljoin(url, suburl)
                        description = a.text.strip()
                        if suburl not in seen:

                            # Add the suburl to the todo list
                            todo.append(suburl)

        print ("links", len(links.keys()))

Output

Performing the code from step 3...

python crawl.py http://www.dmoz.org/Science/Astronomy

... produces the output shown below. The program actually can run for a very long time, after 5 minutes, the crawler has found over 2000 unique links and has moved on to categories like Math History and Physics History. We use ctrl-c to stop the script and preventing it from crawling the entire dmoz website. A next step is to maybe think about when and how to stop the crawler; perhaps after a certain number of links have been found, or else by limiting the number of steps to take away from the starting page.

VISITING http://www.dmoz.org/Science/Astronomy
links 20
VISITING http://www.dmoz.org/Science/Anomalies_and_Alternative_Science/Astronomy%2C_Alternative/
links 39
VISITING http://www.dmoz.org/Science/Social_Sciences/Archaeology/Topics/Archaeoastronomy/
links 94
VISITING http://www.dmoz.org/Science/Physics/Astrophysics/
links 128
VISITING http://www.dmoz.org/Science/Astronomy/Calendars_and_Timekeeping/
links 154
VISITING http://www.dmoz.org/Science/Astronomy/Cosmology/
links 170
VISITING http://www.dmoz.org/Society/Issues/Environment/Light_Pollution/
links 221
VISITING http://www.dmoz.org/Science/Astronomy/Eclipses%2C_Occultations_and_Transits/
links 221
VISITING http://www.dmoz.org/Science/Astronomy/Extrasolar_Planets/
links 250
VISITING http://www.dmoz.org/Science/Astronomy/Extraterrestrial_Life/
links 258
VISITING http://www.dmoz.org/Science/Astronomy/Galaxies/
links 280
VISITING http://www.dmoz.org/Science/Astronomy/Interstellar_Medium/
links 285
VISITING http://www.dmoz.org/Science/Astronomy/Solar_System/
links 320
VISITING http://www.dmoz.org/Science/Astronomy/Star_Clusters/
links 322
VISITING http://www.dmoz.org/Science/Astronomy/Stars/
links 347
VISITING http://www.dmoz.org/Science/Astronomy/Academic_Departments/
links 355
VISITING http://www.dmoz.org/Science/Astronomy/Amateur/
already seen http://www.sundial.thai-isan-lao.com/
links 388
VISITING http://www.dmoz.org/Science/Astronomy/Astronomers/
links 405
VISITING http://www.dmoz.org/Science/Astronomy/Data_Archives/
links 448
VISITING http://www.dmoz.org/Science/Astronomy/Directories/
already seen http://www.cosmobrain.com/
links 457
VISITING http://www.dmoz.org/Science/Astronomy/Education/
already seen http://www.math.nus.edu.sg/aslaksen/teaching/heavenly.shtml
already seen http://www.windows2universe.org/
links 490
VISITING http://www.dmoz.org/Science/Astronomy/History/
links 531
VISITING http://www.dmoz.org/Recreation/Humor/Science/Astronomy/
links 536
VISITING http://www.dmoz.org/Science/Astronomy/Images/
links 575
VISITING http://www.dmoz.org/Science/Astronomy/In_the_Arts/
already seen http://www.lindahall.org/events_exhib/exhibit/exhibits/stars/index.html
links 578
VISITING http://www.dmoz.org/Science/Astronomy/News_and_Media/
links 601
VISITING http://www.dmoz.org/Science/Astronomy/Organizations/
already seen http://planetary.org/
links 619
VISITING http://www.dmoz.org/Science/Astronomy/Amateur/Personal_Pages/
links 676
VISITING http://www.dmoz.org/Science/Astronomy/Popular_Topics/
links 676
VISITING http://www.dmoz.org/Science/Astronomy/Products_and_Services/
links 676
VISITING http://www.dmoz.org/Science/Astronomy/Publications/
links 677
VISITING http://www.dmoz.org/Science/Astronomy/Regional/
links 677
VISITING http://www.dmoz.org/Science/Astronomy/Research_Groups_and_Centers/
already seen http://aa.usno.navy.mil/
links 711
VISITING http://www.dmoz.org/Shopping/Recreation/Science_and_Nature/Astronomy/
links 721
VISITING http://www.dmoz.org/Science/Astronomy/Software/
links 738
VISITING http://www.dmoz.org/Science/Astronomy/News_and_Media/Weblogs/
links 743
VISITING http://www.dmoz.org/Society/People/Women/Science_and_Technology/Astronomy/
links 752
VISITING http://www.dmoz.org/Science/Astronomy/Observatories/
links 807
VISITING http://www.dmoz.org/Science/Astronomy/Planetariums/
links 807
VISITING http://www.dmoz.org/Kids_and_Teens/School_Time/Science/Astronomy_and_Space/
already seen http://www.iau.org/
already seen http://www.pbs.org/deepspace/
already seen http://planetquest.jpl.nasa.gov/
already seen http://www.pbs.org/wgbh/nova/universe/
already seen http://www.space.com/
already seen http://library.thinkquest.org/C0110484/
already seen http://www.windows2universe.org/
links 859
VISITING http://www.dmoz.org/Science/Earth_Sciences/Atmospheric_Sciences/Atmospheric_Physics/
links 882
VISITING http://www.dmoz.org/Science/Physics/
links 896
VISITING http://www.dmoz.org/Science/Technology/Space/
links 907
VISITING http://www.dmoz.org/Science/Anomalies_and_Alternative_Science/Astronomy%2C_Alternative/Cosmology/
links 953
VISITING http://www.dmoz.org/Science/Astronomy/Solar_System/Planets/Mars/Life_on_Mars/
links 961
VISITING http://www.dmoz.org/Science/Anomalies_and_Alternative_Science/Astronomy%2C_Alternative/Planetary_Anomalies/
links 964
VISITING http://www.dmoz.org/Science/Anomalies_and_Alternative_Science/Astronomy%2C_Alternative/Sirius_and_the_Dogon/
links 968
VISITING http://www.dmoz.org/Science/Anomalies_and_Alternative_Science/Geology%2C_Alternative/Velikovsky%2C_Immanuel/
links 976
VISITING http://www.dmoz.org/Science/Astronomy/
already seen http://www.absoluteastronomy.com/
already seen http://aa.usno.navy.mil/
already seen http://astronomicaloptical.blogspot.com/
already seen http://www.astrosociety.org/education/resources/pseudobib.html
already seen http://en.citizendium.org/wiki/Astronomy
already seen http://casswww.ucsd.edu/public/astroed.html
already seen http://www.funtrivia.com/ql.cfm?cat=59
already seen http://www.pd.astro.it/E-MOSTRA/A0000HOM.HTM
already seen http://astronomyonline.org/
already seen http://www.astronomytoday.com/
already seen http://www.cv.nrao.edu/fits/www/astronomy.html
already seen http://www.atlasoftheuniverse.com/
already seen http://www.cosmosportal.org/
already seen http://scienceworld.wolfram.com/astronomy/
already seen http://coolcosmos.ipac.caltech.edu/cosmic_classroom/ir_tutorial/
already seen https://www.lifereader.com/research-articles/logarithmic-maps-of-the-universe
already seen http://muse.univ-lyon1.fr/
already seen http://www.nmm.ac.uk/server/show/conWebDoc.309
already seen http://universe-review.ca/
already seen http://jumk.de/astronomie/astronomy.shtml
links 976
VISITING http://www.dmoz.org/Science/Social_Sciences/Archaeology/Periods_and_Cultures/Mesoamerican/Aztec/Calendar/
links 979
VISITING http://www.dmoz.org/Science/Social_Sciences/Archaeology/Topics/Archaeoastronomy/Mayan/
links 984
VISITING http://www.dmoz.org/Science/Social_Sciences/Archaeology/Topics/Archaeoastronomy/Stonehenge/
links 989
VISITING http://www.dmoz.org/Science/Social_Sciences/Archaeology/Alternative/Archaeoastronomy/
already seen http://www.archaeoastronomy.com/
links 1006
VISITING http://www.dmoz.org/Science/Social_Sciences/Archaeology/Archaeologists/Archaeoastronomers/
links 1009
VISITING http://www.dmoz.org/Science/Social_Sciences/Archaeology/Topics/Archaeoastronomy/Conferences/
links 1011
VISITING http://www.dmoz.org/Science/Social_Sciences/Archaeology/Topics/Archaeoastronomy/Journals/
links 1015
VISITING http://www.dmoz.org/Science/Physics/Relativity/Black_Holes/
links 1034
VISITING http://www.dmoz.org/Science/Astronomy/Stars/Neutron_Stars/
already seen http://www.bigear.org/vol1no1/burnell.htm
links 1053
VISITING http://www.dmoz.org/Science/Astronomy/Stars/Stellar_Evolution/
links 1061
VISITING http://www.dmoz.org/Science/Astronomy/Software/Computational_Astrophysics/
links 1077
VISITING http://www.dmoz.org/Science/Physics/Astrophysics/Research_Groups_and_Centers/
already seen http://www.cfa.harvard.edu/hco/
already seen http://www.cfa.harvard.edu/
already seen http://www.cfa.harvard.edu/sao/
links 1091
VISITING http://www.dmoz.org/Science/Physics/Nuclear/
links 1112
VISITING http://www.dmoz.org/Science/Physics/Particle/Astro_Particle/
links 1113
VISITING http://www.dmoz.org/Reference/Time/Clocks_and_Watches/
links 1118
VISITING http://www.dmoz.org/Science/Reference/Standards/Individual_Standards/ISO/ISO_8601/
links 1159
VISITING http://www.dmoz.org/Science/Astronomy/Solar_System/Planets/Earth/Moon/Phases/
links 1176
VISITING http://www.dmoz.org/Science/Astronomy/Calendars_and_Timekeeping/Sundials/
links 1195
VISITING http://www.dmoz.org/Science/Astronomy/Solar_System/Sun/Sunrise_and_Sunset_Times/
links 1204
VISITING http://www.dmoz.org/Kids_and_Teens/School_Time/Science/Astronomy_and_Space/Time/
already seen http://www.cl.cam.ac.uk/~mgk25/iso-time.html
already seen http://americanhistory.si.edu/ontime/
links 1224
VISITING http://www.dmoz.org/Reference/Time/
already seen http://www.hermetic.ch/cal_stud.htm
already seen http://www-history.mcs.st-andrews.ac.uk/HistTopics/Time_1.html
already seen http://www.cl.cam.ac.uk/~mgk25/iso-time.html
already seen http://www.npr.org/templates/story/story.php?storyId=4572036
links 1238
VISITING http://www.dmoz.org/Science/Astronomy/Amateur/Sky_Calendars/
already seen http://www.sky-watch.com/
links 1248
VISITING http://www.dmoz.org/Science/Technology/Metrology/
links 1252
VISITING http://www.dmoz.org/Society/Holidays/Calendars_and_Lists/
links 1279
VISITING http://www.dmoz.org/Science/Astronomy/Cosmology/Cosmic_Background_Radiation/
links 1287
VISITING http://www.dmoz.org/Science/Astronomy/Cosmology/Cosmological_Constant_and_Dark_Energy/
links 1291
VISITING http://www.dmoz.org/Science/Astronomy/Cosmology/Dark_Matter/
links 1310
VISITING http://www.dmoz.org/Science/Astronomy/Cosmology/Earliest_Universe/
links 1312
VISITING http://www.dmoz.org/Science/Astronomy/Cosmology/Inflation/
links 1315
VISITING http://www.dmoz.org/Science/Astronomy/Cosmology/Large-Scale_Structure/
links 1318
VISITING http://www.dmoz.org/Science/Astronomy/Cosmology/Nucleosynthesis/
links 1320
VISITING http://www.dmoz.org/Science/Astronomy/Cosmology/Topological_Defects/
links 1326
VISITING http://www.dmoz.org/Science/Astronomy/Cosmology/Articles/
links 1332
VISITING http://www.dmoz.org/Science/Astronomy/Cosmology/Courses_and_Tutorials/
links 1334
VISITING http://www.dmoz.org/Science/Astronomy/Cosmology/History/
links 1336
VISITING http://www.dmoz.org/Science/Astronomy/Cosmology/Research_Groups/
links 1342
VISITING http://www.dmoz.org/Science/Astronomy/Cosmology/Software/
links 1344
VISITING http://www.dmoz.org/Science/Physics/Relativity/
already seen http://www.damtp.cam.ac.uk/user/gr/public/
links 1365
VISITING http://www.dmoz.org/Society/Issues/Environment/Light_Pollution/Chats_and_Forums/
links 1369
VISITING http://www.dmoz.org/Society/Issues/Environment/Light_Pollution/News_and_Media/
links 1384
VISITING http://www.dmoz.org/Science/Technology/Lighting/
links 1400
VISITING http://www.dmoz.org/Society/Issues/Environment/Light_Pollution/Opposing_Views/
links 1400
VISITING http://www.dmoz.org/Society/Issues/Environment/Light_Pollution/Regulation/
links 1400
VISITING http://www.dmoz.org/Society/Issues/Environment/Energy/
links 1442
VISITING http://www.dmoz.org/Society/Issues/Environment/Pollution/
links 1445
VISITING http://www.dmoz.org/Science/Astronomy/Eclipses%2C_Occultations_and_Transits/Eclipses/
links 1472
VISITING http://www.dmoz.org/Science/Astronomy/Eclipses%2C_Occultations_and_Transits/Occultations/
already seen http://www.occultations.org/
links 1474
VISITING http://www.dmoz.org/Science/Astronomy/Eclipses%2C_Occultations_and_Transits/Transits/
links 1483
VISITING http://www.dmoz.org/Science/Astronomy/History/Eclipses%2C_Occultations_and_Transits/
links 1488
VISITING http://www.dmoz.org/Science/Astronomy/Products_and_Services/Expeditions/
links 1494
VISITING http://www.dmoz.org/Science/Technology/Space/Missions/Unmanned/Deep_Space/Kepler/
links 1495
VISITING http://www.dmoz.org/Science/Astronomy/Extraterrestrial_Life/Exobiology/
links 1518
VISITING http://www.dmoz.org/Science/Astronomy/Extraterrestrial_Life/Fermi%27s_Paradox/
links 1529
VISITING http://www.dmoz.org/Science/Astronomy/Extraterrestrial_Life/Panspermia/
already seen http://www.panspermia.org/
links 1533
VISITING http://www.dmoz.org/Science/Astronomy/Extraterrestrial_Life/SETI/
links 1549
VISITING http://www.dmoz.org/Society/Paranormal/UFOs/
links 1578
VISITING http://www.dmoz.org/Science/Astronomy/Galaxies/Active_Galactic_Nuclei_-_Quasars/
already seen http://charles_w.tripod.com/quasar.html
links 1584
VISITING http://www.dmoz.org/Science/Astronomy/Galaxies/Milky_Way/
already seen http://mwmw.gsfc.nasa.gov/
links 1592
VISITING http://www.dmoz.org/Science/Astronomy/Amateur/Deep_Sky_Observing/
already seen http://arpgalaxy.com/
already seen http://www.webbdeepsky.com/
links 1610
VISITING http://www.dmoz.org/Science/Astronomy/Interstellar_Medium/Emission_Nebulae/
links 1611
VISITING http://www.dmoz.org/Science/Astronomy/Interstellar_Medium/Planetary_Nebulae/
links 1616
VISITING http://www.dmoz.org/Science/Astronomy/Interstellar_Medium/Reflection_Nebulae/
links 1617
VISITING http://www.dmoz.org/Science/Astronomy/Solar_System/Planets/Earth/
links 1626
VISITING http://www.dmoz.org/Science/Astronomy/Solar_System/Planets/Jupiter/
links 1637
VISITING http://www.dmoz.org/Science/Astronomy/Solar_System/Planets/Mars/
links 1666
VISITING http://www.dmoz.org/Science/Astronomy/Solar_System/Planets/Mercury/
links 1676
VISITING http://www.dmoz.org/Science/Astronomy/Solar_System/Planets/Neptune/
links 1686
VISITING http://www.dmoz.org/Science/Astronomy/Solar_System/Dwarf_Planets/Pluto_and_Charon/
links 1697
VISITING http://www.dmoz.org/Science/Astronomy/Solar_System/Planets/Saturn/
links 1711
VISITING http://www.dmoz.org/Science/Astronomy/Solar_System/Sun/
already seen http://solar-center.stanford.edu/
links 1734
VISITING http://www.dmoz.org/Science/Astronomy/Solar_System/Planets/Earth/Moon/
links 1749
VISITING http://www.dmoz.org/Science/Astronomy/Solar_System/Planets/Uranus/
links 1757
VISITING http://www.dmoz.org/Science/Astronomy/Solar_System/Planets/Venus/
links 1769
VISITING http://www.dmoz.org/Science/Astronomy/Solar_System/Asteroid_Belt/
links 1769
VISITING http://www.dmoz.org/Science/Astronomy/Solar_System/Small_Bodies/
links 1792
VISITING http://www.dmoz.org/Science/Astronomy/Solar_System/Dwarf_Planets/
links 1792
VISITING http://www.dmoz.org/Science/Astronomy/Solar_System/Kuiper_Belt/
links 1810
VISITING http://www.dmoz.org/Science/Astronomy/Solar_System/Oort_Cloud/
links 1811
VISITING http://www.dmoz.org/Science/Astronomy/Solar_System/Planets/
already seen http://pds.jpl.nasa.gov/planets/
links 1814
VISITING http://www.dmoz.org/Science/Astronomy/Amateur/Solar_System_Observing/
links 1815
VISITING http://www.dmoz.org/Science/Astronomy/Solar_System/Conferences/
links 1815
VISITING http://www.dmoz.org/Science/Astronomy/Data_Archives/Solar_System/
already seen http://pds.jpl.nasa.gov/
links 1817
VISITING http://www.dmoz.org/Science/Astronomy/History/Solar_System/
already seen http://www-groups.dcs.st-and.ac.uk/~history/HistTopics/Neptune_and_Pluto.html
links 1821
VISITING http://www.dmoz.org/Science/Technology/Space/Missions/
links 1829
VISITING http://www.dmoz.org/Science/Astronomy/Star_Clusters/Globular_Clusters/
links 1831
VISITING http://www.dmoz.org/Science/Astronomy/Star_Clusters/Open_Clusters/
links 1832
VISITING http://www.dmoz.org/Science/Astronomy/Stars/Binary_Stars/
already seen http://www.phys.lsu.edu/astro/nap98/bf.final.html
links 1842
VISITING http://www.dmoz.org/Science/Astronomy/Stars/Dwarf_Stars/
links 1849
VISITING http://www.dmoz.org/Science/Astronomy/Stars/Names/
links 1853
VISITING http://www.dmoz.org/Science/Astronomy/Stars/Novae_and_Supernovae/
already seen http://chandra.harvard.edu/press/01_releases/press_011001.html
links 1863
VISITING http://www.dmoz.org/Science/Astronomy/Stars/Variable_Stars/
already seen http://www.aavso.org/
links 1869
VISITING http://www.dmoz.org/Science/Astronomy/Amateur/Sky_Maps_and_Atlases/
already seen http://www.lindahall.org/events_exhib/exhibit/exhibits/stars/index.html
links 1892
VISITING http://www.dmoz.org/Science/Astronomy/Data_Archives/Stellar_and_Astrometric/
already seen http://ad.usno.navy.mil/wds/dsl.html
links 1898
VISITING http://www.dmoz.org/Shopping/Recreation/Science_and_Nature/Astronomy/Space_Novelties/Star_Names/
links 1903
VISITING http://www.dmoz.org/Reference/Education/Colleges_and_Universities/
links 1903
VISITING http://www.dmoz.org/Science/Academic_Departments/
links 1912
VISITING http://www.dmoz.org/Science/Astronomy/Amateur/Amateur_Contributions_to_Science/
already seen http://mbond.free.fr/
links 1917
VISITING http://www.dmoz.org/Science/Astronomy/Amateur/Amateur_Telescope_Making/
links 1942
VISITING http://www.dmoz.org/Science/Astronomy/Amateur/Astrophotography_and_CCD_Imaging/
already seen http://www.astropix.com/
links 1988
VISITING http://www.dmoz.org/Science/Astronomy/Amateur/Beginners/
already seen http://home.pcisys.net/~astrogirl/
links 2016
VISITING http://www.dmoz.org/Science/Astronomy/Amateur/Binocular_Astronomy/
links 2023
VISITING http://www.dmoz.org/Science/Astronomy/Amateur/Constellations/
already seen http://www.astro.wisc.edu/~dolan/constellations/
links 2034
VISITING http://www.dmoz.org/Science/Astronomy/Amateur/Observatories/
already seen http://mysite.verizon.net/vzeed81b/
already seen http://www.grimee.com/
links 2044
VISITING http://www.dmoz.org/Science/Astronomy/Amateur/Radio_Astronomy/
already seen http://www.bigear.org/
links 2056
VISITING http://www.dmoz.org/Science/Astronomy/Amateur/Satellites/
already seen http://www.planet4589.org/space/jsr/jsr.html
already seen http://spaceflight.nasa.gov/realdata/sightings/
links 2062
VISITING http://www.dmoz.org/Science/Astronomy/Amateur/Spectroscopy/
already seen http://www.spectrashift.com/
links 2066
VISITING http://www.dmoz.org/Science/Astronomy/Amateur/Star_Parties/
links 2087
VISITING http://www.dmoz.org/Science/Astronomy/Amateur/Telescope_Owner_Resources/
links 2105
VISITING http://www.dmoz.org/Science/Astronomy/Amateur/Chats_and_Forums/
links 2117
VISITING http://www.dmoz.org/Science/Astronomy/Amateur/Classifieds/
links 2122
VISITING http://www.dmoz.org/Science/Astronomy/Amateur/Events/
links 2125
VISITING http://www.dmoz.org/Science/Astronomy/Amateur/Organizations/
links 2126
VISITING http://www.dmoz.org/Science/Astronomy/Amateur/Product_Reviews/
already seen http://www.scopereviews.com/
links 2131
VISITING http://www.dmoz.org/Science/Astronomy/Data_Archives/Supernovae_and_Remnants/
already seen http://www.mrao.cam.ac.uk/surveys/snrs/
already seen http://www.rochesterastronomy.org/snimages/
links 2136
VISITING http://www.dmoz.org/Science/Astronomy/Amateur/Organizations/Directories/
links 2138
VISITING http://www.dmoz.org/Science/Directories/
links 2163
VISITING http://www.dmoz.org/Science/Technology/Space/NASA/Education/
already seen http://quest.arc.nasa.gov/
already seen http://origins.stsci.edu/
already seen http://cse.ssl.berkeley.edu/SegwayEd/index.html
already seen http://www.windows2universe.org/
links 2241
VISITING http://www.dmoz.org/Science/Astronomy/Observatories/Teaching_and_Public/
links 2254
VISITING http://www.dmoz.org/Science/Astronomy/Products_and_Services/Stargazing_Events/
links 2256
VISITING http://www.dmoz.org/Science/Astronomy/Software/Education_and_Multimedia/
links 2267
VISITING http://www.dmoz.org/Science/Astronomy/Products_and_Services/Educational_Resources/
links 2276
VISITING http://www.dmoz.org/Shopping/Entertainment/Recordings/Video/Science/
links 2284
VISITING http://www.dmoz.org/Science/Physics/Education/
already seen http://microgravity.grc.nasa.gov/DIME.html
already seen http://www.grc.nasa.gov/WWW/K-12/Numbers/Math/Mathematical_Thinking/index.htm
already seen http://www.colorado.edu/physics/2000/
links 2363
VISITING http://www.dmoz.org/Science/Technology/Space/Education/
already seen http://www.challenger.org/
already seen http://www.phy6.org/stargaze/Sintro.htm
links 2380
VISITING http://www.dmoz.org/Science/Astronomy/History/Instruments/
links 2384
VISITING http://www.dmoz.org/Science/Astronomy/History/Observatories/
links 2387
VISITING http://www.dmoz.org/Science/Astronomy/History/People/
already seen http://www.astrosociety.org/education/resources/womenast_bib.html
links 2397
VISITING http://www.dmoz.org/Science/Astronomy/History/Worldviews/
links 2408
VISITING http://www.dmoz.org/Science/Math/History/
links 2436
VISITING http://www.dmoz.org/Science/Physics/History/
links 2474