Structure of the Universe

JPL research on the Structure of the Universe covers a wide array of topics that address understanding the evolution of the universe beginning with the formation of the first galaxies and continuing until the present time.  These studies include observations of ultra-, hyper- luminous galaxies, of active galactic nuclei, dark energy, and the distribution of matter in the universe.  Researchers study their physics and their impact through observations at all wavelengths. This research also includes studies of general relativity and its applications, brown dwarf stars, and star formation and its impact in the Galaxy and the local universe.


Current Research Tasks

  • Galaxy evolution, galaxies and galaxy clusters at high redshift, active galactic nuclei, galaxy alignment, dark matter and dark energy
  • Studies of interstellar line emission probing interstellar molecular clouds and star forming regions of the Milky Way and other galaxies
  • Intensity mapping to probe galaxies in the early universe by their aggregate emission


Selected Research Topics


Gravitational Lensing

Hubble image
Hubble Space Telescope image shows Einstein ring of one of the Sloan Lens ACS (SLACS) gravitational lenses, with the lensed background galaxy enhanced in blue. 

Weak and strong gravitational lensing can help solve the puzzle of dark energy by aiding in mapping of the history of the universe’s expansion, measuring the growth of structure, and even probing the very nature of dark matter. Research efforts at JPL are focused on theory and modeling, working with state of the art data from space as well as ground-based observatories, and developing future space missions that would optimally use weak lensing and discover and exploit strong gravitational lenses to solve these fundamental problems. To those ends, JPL researchers are active participants in many missions and collaborations including Euclid, WFIRST, the LSST, the Sloan Lens ACS (SLACS) Survey, the Hubble Space Telescope (HST), Coordinates, Sizes, Magnitudes, Orientations, and Shapes (COSMOS) Survey, Cluster Lensing And Supernova Survey with Hubble (CLASH), and others.



Composite NuSTAR image
A composite image composed of NuSTAR data (in magenta) and an optical image of the spiral galaxy IC 342.  The two magenta spots show two very active black hole systems – too powerful to be stellar-mass black holes, but not powerful enough to be AGN. These may be candidates for the elusive “intermediate mass” black holes often predicted, but not yet confirmed to exist. Image Credit: NASA

The Nuclear Spectroscopic Telescope Array (NuSTAR) is the first focusing hard X-ray telescope in orbit, allowing true imaging in this largely unknown region of the spectrum. The telescope array has been conducting a census of black holes on all scales, mapping newly-created radioactive material in nebulae from recently-exploded stars, and exploring jets of plasma ejected at nearly the speed of light from the most powerful AGN in order to understand what powers these giant engines. 


Spitzer Space Telescope

In addition to studying the origin of stars and planets, the Spitzer infrared observatory is also used to study galaxies at distances so great that it allows us to see them as they existed billions of years ago. All light from these galaxies is stretched by the expansion of the universe to about twice its normal wavelength. (For example, the emission line of oxygen with a wavelength of 0.501 μm and the H| | line at 0.656 μm are shifted to 1.0 and 1.3 microns.) While local galaxies can be studied at optical wavelengths, high redshift galaxies are best studied in the infrared. Spitzer has exhausted its cryogenic coolant as per plan, but the observatory is still being operated as a warm mission (only cooled to the temperature of cold space).