The Hubble Space Telescope achieved another milestone in its 21 years of astronomy. The 10,000th refereed science paper has been published. In July, Hubble recorded its one millionth observation to the data archive as reported in this diary by palantir. Generations of astronomers to come will benefit from this collection.
The 10,000th paper's lead author is Zach Cano of the Astrophysics Research Institute, Liverpool John Moores University, Liverpool, United Kingdom. He reports on the identification of the faintest supernova ever associated with a long-duration gamma-ray burst -- an intense gusher of high-energy radiation following the death of a star.
Astronomers from 35 countries have used Hubble for research in astronomy. The top five outside of the United States are the United Kingdom, Germany, Italy, France, and Spain.
Come below the squiggle for more details about this milestone.
Hubble and All Sky Coverage |
It was a rough beginning for Hubble. Deployed in orbit on April 25, 1990, astronomers discovered on June 25, 1990 it couldn't focus sharply. Software was used to some degree of success until a repair mission December 2, 1993 corrected the optics and brought images into sharp focus. There have been 4 repair missions to Hubble. Mission 2 started February 11, 1997. Mission 3A and 3B were started December 19, 1999 and March 1, 2002 respectively. Mission 4 started May 11, 2009. These missions performed a number of repairs, replacements, upgrades, and installations of new equipment to keep the spacecraft functioning at peak performance. This link highlights the
missions and milestones in a timeline.
Hubble's observations cover a huge portion of the sky. This all sky map illustrates the coverage as of June 2011. The types of objects studied are color coded.
Statistics by Year and Instrument |
Hubble is outfitted with a large number of scientific instruments. The chart and table below show the number of papers from each. In addition, this link describes each instrument and its location.
Top Areas of Study Briefly Reviewed |
From orbit about 350 miles above the surface of Earth, Hubble can see farther and more clearly than any ground based telescopes. Advances are being made in adaptive optics bringing ground based telescopes closer in performance to Hubble. Thanks to the maintenance missions, Hubble is 100 times more powerful than when it was launched. It has brought the universe and wonders of the heavens into our homes, our classrooms, and into public discussion like no other instrument before. Some of Hubble's greatest discoveries are described below.
Dark Energy, Accelerating Universe, and Supernovae
By using bursts of light from distant supernovae to measure the expansion of space, Hubble provided evidence for the existence of a “dark energy” that exists everywhere in the universe. Dark energy exerts a repulsive force against gravity and causes the universe to expand at an ever-faster rate. Dark energy has been accelerating the expansion for the past 5 billion years. The 2011 Nobel Prize in Physics was awarded for this work. The story is described in detail in a great diary by my friend palantir.
When supernova 1987a erupted, Hubble provided astounding views. It also allowed astronomers to carefully monitor the progress in detail as the shock wave expanded into the surrounding region. The image below shows the beauty of that interaction.
The Age of the Universe
Prior to Hubble, it was assumed the universe was between 10 and 20 billion years old. The sharp eye of Hubble allowed astronomers to see the pulsating class of standard candle stars called Cepheid Variables out to much greater distances. Knowing the true brightness and distance and the behavior of expansion called Hubble's Law, the age of the universe is now known to an accuracy of about 3.3%. It is about 13.75 billion years old.
Hubble Deep Field and Ultra-Deep Field Images
The telescope showed that the universe has grown and changed over time as evidenced by the ways galaxies grew and merged with other galaxies to become the large ones we see today. The Deep Field and Ultra-Deep Field images look back in time to the small and immature galaxies as far back in time to an age of 450 million years after the Big Bang.
Extra-Solar Planets
Today, there are several hundred extra-solar planets orbiting other stars besides the Sun. Hubble showed that the atmosphere of some of these planets contain sodium, oxygen, carbon, and hydrogen. Some contain carbon dioxide, methane, and water. These are elements basic to life suggesting the chemistry is present there. Hubble also made the first visible light image of an extra-solar planet around the star Fomalhaut, 25 light years from us.
The Dark Matter Mystery
Hubble has allowed astronomers to map regions of space in 3-D with the concentrations of Dark Matter. It cannot be seen directly, only inferred by its influence. They look for the bending and distorting of light from more distant galaxies by the nearer dark matter. This phenomenon is called gravitational lensing.
Remarkable and Beautiful Images |
In addition to the top scientific discoveries, Hubble has provide us with an amazing display of the beauty and variety to be found in the heavens. Everyone has some favorites. Here are 3 of mine. The link below these images will allow you to browse the galleries of images and find many more.
Most of the images used to illustrate this diary and Hubble's great achievements come from HubbleSite and its huge archive of images, videos, and multi-media holdings.
James Webb - The Telescope of the Future |
This is the subject for many future diaries. Here is an interesting look at the next generation of space telescope. The
Webb Telescope will be placed almost a million miles from Earth. It will view in the infrared portion of the spectrum. Light from the early universe has expanded due to redshift into the longer infrared portion. This telescope will allow us to look back farther in time to that era. Launch is planned for later in the decade. It is a large, monumental, and costly undertaking backed by fifteen countries: Austria, Belgium, Canada, Denmark, France, French Guyana, Germany, Ireland, Italy, the Netherlands, Spain, Sweden, Switzerland, the United Kingdom, and the United States. NASA is the lead partner on the project, working in conjunction with the European Space Agency (ESA) and the Canadian Space Agency (CSA).. The mission should last from 5 to possibly more than 10 years.
For a multi-media interactive tour of the telescope, click on the image below. Allow time for it to load. Caution if you have a slow connection. Explore the telescope and its components.
Let's hope the Webb will prove to be a worthy successor to Hubble and provide us with many more years of amazing astronomical research and views.