Illustration of Determining Stages of Interacting Galaxies

Stellar Fireworks Accompany Antennae Galaxy Collision

This Hubble Space Telescope image provides a detailed look at a brilliant "fireworks show" at the center of a collision between two galaxies. Hubble has uncovered over 1,000 bright, young star clusters bursting to life as a result of the head-on wreck. [Left] A ground-based...

Close-Up of Star Formation in Antennae Galaxy

These four close-up views are taken from a head-on collision between two spiral galaxies, called the Antennae galaxies, seen at image center. The scale bar at the top of each image is 1,500 light-years across. [Left images] The collision triggers the birth of new stars in...

NGC 4038/4039, Antennae

Fireworks Show in Collision of Antennae Galaxies (NGC 4038/4039)

NGC 4038/4039, Antennae

Close-Up of Star Formation in the Antennae Galaxy (NGC 4038/4039)

Antennae Galaxy Closeup (NGC 4038/4039 )

Milky Way/Andromeda Collision (Phase 1)

Milky Way/Andromeda Collision (Phase 2)

Milky Way/Andromeda Collision (Phase 3)

Milky Way/Andromeda Collision (Phase 4)

Milky Way/Andromeda Collision (Phase 5)

Eagle Nebula with a representation of a giant molecular cloud

Shown here HST image of Eagle Nebula with part of its associated GMC. Since molecular hydrogen gas can only be observed by radio technique, contour lines are here used to show where the optically invisible hydrogen gas lies. The manner in which GMCs form stars may strongly...

NGC 5426/5427

NGC 4038/4039

NGC 7252

NGC 3610

Ground-Based Image of M87

Digitized Sky Survey Image of the active elliptical galaxy M87.

HST image of an old globular star cluster in galaxy M31

We believe our HST observations of NGC 4038/4039 and other merger galaxies also shed some new light on how young globular clusters form, i.e., from giant clouds of hydrogen gas that astronomers call Giant Molecular Clouds. Full-grown spiral galaxies like the Milky Way have...

Central region of our HST image of NGC 7252

In NGC 7252, where we had discovered ~40 globular clusters with the Hubble before its refurbishment, we have recently discovered ~500 globulars with the refurbished telescope. Each of bluish pointlike sources is a likely globular.

Central region of HST image of NGC 3921

In NGC 3921, we have discovered over 100 new young clusters. There are two reasons to believe that all these young clusters formed from GMCs in the merging spiral galaxies. First, in all three galaxies (N4038/39, N7252, N3921) the young clusters show same, characteristic...

HST/WFPC2 image of colliding galaxies NGC 4038 and NGC 4039

Includes an image made in red light from hydrogen gas.

HST/WFPC2 image of galaxy NGC 3921

HST/WFPC2 image of galaxy NGC 7252

Galaxy Merger Evolution Sequence

Zoom into the Antennae

Hypothetical Collision of the Milky Way with the Andromeda Galaxy

Computer Simulation: The Formation of the Antennae Pair