Deep Space
Most Distant Galaxy:
The most distant galaxy observed and confirmed by the NASA Ultra Deep Field project is GN-z11 with a redshift of 11.1 or 13.39 billion years away and almost 200 million years closer to the Big Bang. Images from Hubble and Spitzer show that GN-z11 is 25 times smaller than the Milky Way and approximately. However, GN-z11 is very small, it is forming new stars with a ratio of 20 times more than our galaxy (NASAWeb-I)
Figure 1: Image from the farthest galaxy GN-z11 superimposed on an image from the GOODS-North survey.
Credits: NASA, ESA, P. Oesch and B. Robertson (University of California, Santa Cruz), and A. Feild (STScI) (NASAWeb-I)
Figure 2: infographic image from farthest galaxies known so far. Hubble spectroscopically confirms the farthest galaxy to date.
Credits: NASA, ESA, P. Oesch and B. Robertson (University of California, Santa Cruz), and A. Feild (STScI) (NASAWeb-I)
Cosmic microwave background (CMB)
Cosmic microwave background (CMB) image was observed by the space telescope Planck (Figure 1). This image is a snapshot from the early universe when the universe was 380,000 years old. In the image, the universe displays small temperature variations from regions where the densities change (ESAWeb-I).
The Planck space telescope is observing the universe at wavelengths between 0.3 mm to 11.1 mm which are the frequencies 27Ghz to 1 THz (far-infrared, microwave, and high-frequency radio domains). The principal objective of this telescope is to study CMB which are remains of radiation left from the Big Bang. The CMB is leftover radiation from when the universe was created about fourteen billion years ago. The presence of CMB was proposed by George Gamow, Ralph Alpher, and Robert Herman in the 40s when they were studying the nucleosynthesis of elements such as hydrogen, helium, and lithium. The CMB was detected for the first time in 1964 by Arno Penzias and Robert Wilson. They won the Nobel Prize in Physics in 1978 for their discovery. (ESAWeb-I)
Before the Planck space telescope, NASA sent the first space mission to record the CMB in 1989. This mission discovered that CMB has a spectrum of a blackbody with temperatures of 2.73 kelvin. For those discoveries, John Mather and George Smoot got the Nobel Prize in Physics in 2006. In 2001, NASA sent a second space mission which is known as Wilkinson Microwave Anisotropy Probe (WMAP), this mission studied the small variations in temperature and they discovered that these very small variations in temperature in the CMB were left by the matter and photons unpair 380,000 years after the Big Bang. WMAP helped to identify the components of the universe and helped to build the modern model of cosmology. (ESAWeb-I)
Figure 3: Planck CMB, Released 21/03/2013, Credit: ESA and the Planck Collaboration (ESAWeb-I)
Abell 370
On May 4, 2017, Nasa released the image of Abell 370, a galaxy cluster composed of more than a hundred galaxies all bound together by gravity. This cluster is located six billion light-years away from us in the Cetus Constellation. Abell 370 is so massive that it causes the light of background galaxies to become anamorphic and amplified (Figure 1). This phenomenon produced by the massive gravitational influence of the cluster creates a magnified effect that helps astronomers with better visualization of the galaxies behind and farther away than the cluster(NASAWeb-I).
This image of Abell 370 was taken by the Hubble Space telescope after more than 600 hours of observation time and orbits of the Earth, respectively. This observation is part of the Frontier Fields program which is a collaborative effort by NASA and ESA. The main objective of this program is to perform the deepest observations of the universe in order to help astronomers understand how stars and galaxies evolved after the Big Bang when space was opaque and repleted with Hydrogen (NASAWeb-I).
Moreover, in these deep field observations, Hubble also computed six parallel fields close to Abell 370 (Figure 2). These observations are helping astronomers to understand the distributions of normal and dark matter in those clusters. Lastly, the most important part of this release demonstrated that astronomers now have a full dataset of these clusters which is the most complete dataset of the early universe ever captured (NASAWeb-I).
Figure 4: Abell 370, a galaxy cluster Hubble Space Telescope
Credit: NASA, ESA, and J. Lotz and the HFF Team (STScI) NASAWeb-I
Figure 5: Abell 370 parallel field, imaged taken by a Hubble Deep Field
Credit: NASA, ESA/Hubble, HST Frontier Fields NASAWeb-I
References
NasaWeb-I Morrow, A. 2016, NASA, http://www.nasa.gov/feature/goddard/2016/hubble-team-breaks-cosmic-distance-record (Accessed May 7, 2017)
ESAWeb-I European Space Agency, http://www.esa.int/Our_Activities/Space_Science/Planck/Planck_and_the_cosmic_microwave_background (Accessed May 7, 2017)
Boylan-Kolchin, M., Weisz, D. R., Bullock, J. S., & Cooper, M. C. 2016, Mon Not R Astron Soc Lett, 462, L51
Dunlop, J. S., McLure, R. J., Biggs, A. D., et al. 2017, Mon Not R Astron Soc, 466, 861
ESOWeb-I www.spacetelescope.org, http://www.spacetelescope.org/news/heic1711/ (accessed May 7 2017)
NASAWeb-I Hille, K. 2017, NASA, http://www.nasa.gov/feature/goddard/2017/a-lot-of-galaxies-need-guarding-in-this-hubble-view (accessed May 7 2017)
SpaceWeb-I Weitering, H., 5, S. W.-P. | M., & ET, 2017 Space.com, http://www.space.com/36726-hubble-galaxies-need-guarding.html (accessed May 7 2017)
Umehata, H., Tamura, Y., Kohno, K., et al. 2017, Astrophys J, 835, 98
