APOD 3.7

"The center" takes you to an APOD entitled "Journey to the Center of the Galaxy."
"is hidden" takes you to an APOD entitled "The Milky Way in Stars and Dust."
"this stunning vista" takes you to a site where more pictures of this part of the sky can be found.
"infrared" takes you to a site on infrared astronomy.
"false-color image shows" takes you to a site on the Spitzer.
"galactic center" takes you to an APOD entitled "At the Center of the Milky Way."
"Sagittarius" takes you to a Hawaiian astronomy site about the constellation.

APOD 3.6

"dreamlike" takes you to a gallery of "dreamlike" pictures.
"Alborz Mountain Range" takes you to the Wikipedia entry on the range.
"Betelgeuse" takes you to a description of the star.
"of Orion" takes you to a sky map of Orion.
"Sirius" takes you to a description of the star.
"of Canis Major" takes you to a Hawaiian astronomy site.
"Earth's night" takes you to a site about the brightest stars.
"the Caspian Sea" takes you to a google map of the sea.

Planetary Nebula

http://www.seds.org/messier/planetar.html
http://fusedweb.pppl.gov/CPEP/Chart_Pages/5.Plasmas/Nebula/Planetary.html
http://www.astro.washington.edu/balick/WFPC2/
http://www.blackskies.org/pnweek00.htm
http://www.answers.com/topic/planetary-nebula
http://www.ing.iac.es/PR/press/iphasPN.html
http://antwrp.gsfc.nasa.gov/apod/planetary_nebulae.html
http://hubblesite.org/newscenter/archive/releases/nebula/planetary/
http://www.kopernik.org/images/archive/m27.htm
http://space.mit.edu/PN_conf/
http://www.ing.iac.es/PR/dissemination/articles/PNe.html
http://www.astrosurf.com/buil/us/spe6/planet.htm
http://www.glyphweb.com/esky/default.htm?
http://wisp.physics.wisc.edu/benjamin/glimpse/pn.html
http://www.williams.edu/Astronomy/research/PN/nebulae/nebulaegallery.php
http://www.ucl.ac.uk/star/research/stellarenvironment/cieresearch/planetarynebulae
http://www.astro.cornell.edu/academics/courses/astro201/nebulae_planetary.htm
http://www.astro.su.se/aar9798/node26.html
http://www.biochem.szote.u-szeged.hu/astrojan/nebula1.jpg
http://boojum.as.arizona.edu/~jill/EPO/Posters/PlanetaryNebula/pnepic.gif
http://laserstars.org/news/NGC7027.jpg
http://zebu.uoregon.edu/~imamura/208/feb22/ring_nebula.gif
http://universe-review.ca/I08-09-planetarynebula1.jpg
http://narrowbandimaging.com/images/jones_emberson_ak_rc.jpg
http://www.celestiamotherlode.net/catalog/images/screenshots/various/nonmessiernebulae_NGC3132_Eight_Burst_Neb_1__jll.jpg
http://www.exchangedlife.com/Cosmos/images/Round%20Planetary%20Nebula.jpg
http://heritage.stsci.edu/1998/39/ngc3132/hotspring.gif
http://www.sedonawolf.com/Photos/images/Nebula.JPG
http://filer.case.edu/~sjr16/media/hst_heritage_0009.jpg

APOD 3.5

"Comet Naught" takes you to a site with multiple pictures of the comet.
"conjunction" takes you to Wikipedia where you can read all about conjunction.
"enjoyed by denizens" takes you to a spanish site with more pictures of the moon.
"near Cordoba" takes you to another spanish site about a trip someone went on.
"Venus and" takes you to an APOD entitled "Crescent Venus and Moon."
"Castle Almodovar" takes you to another spanish site about the the castle.
"castle's" takes you to an APOD entitled "Big Dipper Castle."