In this talk I'll try to give you a sense of the many types of activity going on above us, starting from the Solar System and moving outward.  I am going to rely heavily (for this Web version, entirely) on pictures and animations other people have posted on the Internet. (Many of the animations will require the ability to view mpeg, AVI, quicktime, or realvideo, and sizes are several megabytes.) Let's begin...

The Sun ( learn more )
Our star, the Sun, is a bubbling ball of gas heated (on low simmer) by nuclear fusion. It has a strong magnetic field that can lift immense plumes of gas bigger than the Earth, and it flings away a wind that protects us from many of the cosmic rays that fill the Milky Way -- but that also can puff up Earth's outer atmosphere, cause auroras, and interfere  with our satellites. Watching the surface of the Sun jiggle, astronomers can even get a very good idea of what the inside of the sun is like (helioseismology). Here are a different views of the Sun:

• Solar Flares in Ultraviolet Light: Trace Movie 1 (limb view) --  TRACE movie 2  (face-on) -- (links to more)
• Solar Prominences:  SOHO movie 1  --  The Whole Sun --  another -- (info)
• Convection Granules:  small near-IR move ( info );  Giant solar convection cells:  animation -- (info)
• Comets Strike (or miss) the Sun!:  Close up --  Wide view  --  '96 Christmas Comet --  Hyakutake  -- (info)
•  Link: The Sun Today
•  Helioseismology: The Sun's Hum (audio)  (info)

Computer simulation of convection within a Red Giant star. (info)

Eta Carinae: This very massive star (~120 Suns) is a Luminous Blue Variable in the Keyhole Nebula. It had a major eruption in 1843 and cast off an immense amount of gas that is now expanding in two (mysterious)  dumbell-shaped lobes. (info)
        Movies:  Expansion('85-'97) -- flicker ('95 & '97) -- zoom-in ('92-'95)

Wolf-Rayet/O-star binaries: These are big brother, little brother pairs of massive stars, orbiting each other. Big brother's wind blows little brother's wind back into a narrow cone; the cone is wrapped into a spiral, like the water from a sprinkler. The cone is lit up by dust that forms in the O star's wind and warmed by the light from the two stars; this makes it glow in the near-infrared. The result is a Pinwheel Nebula, and it's about five times larger than our Solar System -- but so far away that special techniques are required to make these images. (info [Tuthill & Monnier])
       Movies: Wolf-Rayet 104 --  W-R 98a  --  W-R 112  (from  John Monnier at the Harvard-Smithsonian Center for Astrophysics)

Carbon Stars: These are old sun-like stars that are becoming giants (about the size of Earth's orbit) for the second and last time; they've eaten their inner planets if they had any; and soon, they'll cast off their envelopes and become cinders (white dwarfs) at the centers of planetary nebulae. They pulsate erratically and emit thick, slow, dusty winds that make them nearly invisible in ordinary light but extremely bright in the infrared. The knots and wisps in these winds are a challenge to high-resolution astronomy and a clue to how planetary nebulae get their shapes.
      Movies:  IRC +10216 --  CIT 6  (from John Monnier)

SiO Masers around the Mira variable star TX Cam: Similar to carbon stars, this star pulsates and drives a thick wind. Here is a movie of the gas around the star, lit up by "masers" whose light is beamed at us like natural lasers. It covers a year and a half, and was compiled by Phil Diamond at Jodrell Bank. The star is a giant; it's about half the size of the ring of masers. Note the striking resemblance to some of the solar prominences shown above!   (info)

Forming Stars: Stars are formed as a gas cloud collapses inward under its own weight. However, some of this gas gets flung away in extremely powerful jets. These jets can punch through the parent gas cloud and cast a lot of it away... making it hard to turn clouds into stars!
-- Hubble's Variable Nebula: here you can see the light of the star reflected in the hole along the axis of the cloud that's falling into it, so shadows of little gas clouds can be seen crossing the reflection. (info)
-- Protostellar Winds, Jets, and Outflows: Here you can see the gas jets themselves, and the shocks inside them:
Movies: XZ Tauri ('95-'98) --  HH 30  (info);
                HH1/HH2 outflow:  Overview --  Jet Shocks on one side --  Jet Shocks on Other Side -- (Courtesy of  John Bally)
Images:  protostellar jets --  pre-planetary disks --  more disks --  Trifid nebula --  Eagle Nebula --  Proplyds
Info:  Montreal Star Formation Group  -- Alyssa Goodman's, Lynne Hillenbrand's,
           and Bo Reipurth's star formation links;  Doug Johnstone's  Orion page;
           my overview  and talk on protostellar feedback in star formation

Supernova Explosions:
-- Suppose you're a star and your long-time companion decides to explode on you... how messy do things get?
      Find out with the computer simulations by Marietta, Burrows, & Fryxell.
-- Watch this simulation by Burrows of the interior of a collapsing star.
 Supernova 1987A  in the Tarantula Nebula in the Large Magellanic Cloud:
        a Hubble movie of its expanding ejecta and another of its fastest ejecta striking the dense "inner ring" (info)
Supernova 1993J in the nearby galaxy M81:
        a  radio movie of its expanding ejecta by Norbert Bartel (info)

Neutron Stars:
The Crab Pulsar:  Hubble movie of shocks and ripples in the relativistic wind (info)
                                 The Chandra X-ray Observatory's  image of the Crab pulsar's jet ( info )
     The present-day Crab Nebula was created by a supernova in 1054 recorded by Chinese
      astronomers. Many people think that this petrograph in Chaco canyon, New Mexico,
      is a depiction of that explosion, which would have been very bright in the sky.
      (Info:  Chaco Canyon --  the petrograph --  the Crab nebula )
 Pulsars are spinning neutron stars:
 Animation of a radio pulsar

Black Holes:
Small black holes:  Animation of a star-mass black hole, a "microquasar" swallowing mass from a companion star
Mid-sized holes: Movie of a mid-sized black hole? in the nearby galaxy M82 by the Chandra X-Ray Observatory
     -- this caused quite a stir recently, because we have little idea how such a thing could form (info)
Immense holes: " Searchlight " from the massive black hole in the center of M82
                              (much bigger than the previous one) (info)
            Watch as stars orbit the black hole at the center of the Milky Way (a small version of M82's -- only 2.5 million
             Suns in mass) (info)
Superluminal Jets:  Movie of a jet of gas squirting out of a massive black hole at the center of the radio galaxy 3C 120.
           The jets seem to be moving faster than the speed of light (they go a few light years in less than one year),
           but this is an optical illusion made possible by the fact that they're moving toward us and almost keeping up
           with the light they've emitted -- so we see the whole process sped up.
          ( info  from Brian Marscher at Boston U.)

Info: the Chandra Observatory

Links to more: I recommend the Astronomy Picture of the Day.
Questions or comments?Please contact me... I'll do my best to respond promptly.