Deep Space is really about those structures which are so far from us that we cannot do much more than estimate their number, check their speed, and maybe their size. There are billions of galaxies in Deep space….and they are moving away from us very fast!
Every spot of light are galaxies(except the two or three with “spikes”, these are stars in our own galaxy which happened to be in the field of view). Several hundred never before seen galaxies are visible in this “deepest-ever” view (at the time) of the universe, called the Hubble Deep Field (HDF). Besides the classical spiral and elliptical shaped galaxies, there is a bewildering variety of other galaxy shapes and colors that are important clues to understanding the evolution of the universe. Some of the galaxies may have formed less that one billion years after the Big Bang.
The image was assembled from many separate exposures (342 frames total were taken, 276 have been fully processed to date and used for this picture) with the Wide Field and Planetary Camera 2 (WFPC2), for ten consecutive days between December 18 to 28, 1995. This picture is from one of three wide-field CCD (Charged Coupled Device) detectors on the WFPC2.
This “true-color” view was assembled from separate images were taken in blue, red, and infrared light. By combining these separate images into a single color picture, astronomers will be able to infer — at least statistically — the distance, age, and composition of galaxies in the field. Bluer objects contain young stars and/or are relatively close, while redder objects contain older stellar populations and/or farther away.
Ultra- Deep Space
This is a photo of Ultra-deep Space taken by the Hubble Space Telescope in 2009, after its last major upgrade.
The photo, called the Ultra-Deep Field, or UDF, was taken with the new Infrared camera, WFC3/IR, in late August 2009 during a total of four days of pointing for 173,000 seconds of total exposure time. Infrared light is invisible and therefore does not have colors that can be perceived by the human eye. The colors in the image are assigned comparatively short, medium, and long, near-infrared wavelengths (blue, 1.05 microns; green, 1.25 microns; red, 1.6 microns). The representation is “natural” in that blue objects look blue and red objects look red. The faintest objects are about one-billionth as bright as can be seen with the naked eye.
NASA’s Hubble Space Telescope has made the deepest image of the universe ever taken in near-infrared light. The faintest and reddest objects in the image are galaxies that formed 600 million years after the Big Bang. No galaxies have been seen before at such early times. The new deep view also provides insights into how galaxies grew in their formative years early in the universe’s history.
eX-treme Deep Space
Called the eXtreme Deep Field, or XDF, the photo was assembled by combining 10 years of NASA Hubble Space Telescope photographs taken of a patch of sky at the center of the original Hubble Ultra Deep Field. The XDF is a small fraction of the angular diameter of the full Moon.
The Hubble Ultra Deep Field is an image of a small area of space in the constellation Fornax, created using Hubble Space Telescope data from 2003 and 2004. By collecting faint light over many hours of observation, it revealed thousands of galaxies, both nearby and very distant, making it the deepest image of the universe ever taken at that time.
The new full-color XDF image reaches much fainter galaxies, and includes very deep exposures in red light from Hubble’s new infrared camera, enabling new studies of the earliest galaxies in the universe. The XDF contains about 5,500 galaxies even within its smaller field of view. The faintest galaxies are one ten-billionth the brightness of what the human eye can see.
Magnificent spiral galaxies similar in shape to our Milky Way and the neighboring Andromeda galaxy appear in this image, as do the large, fuzzy red galaxies where the formation of new stars has ceased. These red galaxies are the remnants of dramatic collisions between galaxies and are in their declining years. Peppered across the field are tiny, faint, more distant galaxies that were like the seedlings from which today’s striking galaxies grew. The history of galaxies — from soon after the first galaxies were born to the great galaxies of today, like our Milky Way — is laid out in this one remarkable image.
Hubble pointed at a tiny patch of southern sky in repeat visits (made over the past decade) for a total of 50 days, with a total exposure time of 2 million seconds. More than 2,000 images of the same field were taken with Hubble’s two premier cameras — the Advanced Camera for Surveys and the Wide Field Camera 3, which extends Hubble’s vision into near-infrared light — and combined to make the XDF.
“The XDF is the deepest image of the sky ever obtained and reveals the faintest and most distant galaxies ever seen. XDF allows us to explore further back in time than ever before,” said Garth Illingworth of the University of California at Santa Cruz, principal investigator of the Hubble Ultra Deep Field 2009 (HUDF09) program.
The universe is 13.7 billion years old, and the XDF reveals galaxies that span back 13.2 billion years in time. Most of the galaxies in the XDF are seen when they were young, small, and growing, often violently as they collided and merged together. The early universe was a time of dramatic birth for galaxies containing brilliant blue stars extraordinarily brighter than our Sun. The light from those past events is just arriving at Earth now, and so the XDF is a “time tunnel into the distant past.” The youngest galaxy found in the XDF existed just 450 million years after the universe’s birth in the big bang.
Hubble Space Telescope, launched from the Space Shuttle on April 24, 1990.
The Hubble Space Telescope is considered the Window to the Universe. Just as Galileo’s telescope opened the night sky to astronomers of the day thus improving observations dramatically, the Hubble Space Telescope has given modern astronomers the same level improvement in observations. However, it’s beginning was a fiasco. Launched in 1990 it was immediately a disaster! The primary mirror was defective and the pictures were very poor quality. Nevertheless, the scientist evaluated the problem and designed a corrective lens, which was installed 3 years and a billion dollars later. The results were astonishing and Hubble has been breaking new ground continuously for 25 years. It was repaired in 2009 and improved by astronauts aboard the Space Shuttle Atlantis and with a little luck will continue for several more years. Nearly every Astronomy book written since 1995 has many photos of galaxies and nebulae only possible because of the Hubble Telescope.
Before Hubble was launched in 1990, astronomers could barely see normal galaxies to 7 billion light-years away, about halfway across the universe. Observations with telescopes on the ground were not able to establish how galaxies formed and evolved in the early universe.
Hubble gave astronomers their first view of the actual forms and shapes of galaxies when they were young. This provided compelling, direct visual evidence that the universe is truly changing as it ages. Like watching individual frames of a motion picture, the Hubble deep surveys reveal the emergence of structure in the infant universe and the subsequent dynamic stages of galaxy evolution.