Hubble Space Telescope – The Hubble Space Telescope
An unauthorised copy has been obtained this week of Hubble’s first two Space Telescope images. Although the telescope has now been retired, the results will be vital information for astronomers as they attempt to decipher the mysteries of the Universe: the evolution of the formation of galaxies over long time spans, the existence of dark energy and the nature of gravitational lensing.
The Hubble Space Telescope – which was launched in 1990 – is the best of NASA’s astronomical exploration satellites, having been used to make the first-ever images of Saturn and Mercury.
Hubble’s successor – the James Webb Space Telescope – is scheduled to launch before the end of 2014 and will become the second in NASA’s ‘high-end’ science mission – a high-tech successor to the Hubble.
We will have a chance to witness the first images of the Webb Telescope’s main mirror from space on Monday (9th May) with the launch of its first science satellite.
The Hubble images were taken using the very first ‘space telescope’ ever built – the Hubble Space Telescope – on 30th June 1990. The images are based on the telescope’s first ten orbits (about seven months). There is no explanation as to why the telescope was allowed to fly this long, except that it wanted to see what its sister telescope, known as the Wide Field Camera (WFC) in Hubble’s ‘science-grade’ mode, would show.
The images of Saturn have been the most famous of NASA’s first space ‘sights’, the first images ever captured from space of such a well understood world. Here we see Saturn from the WFC, a view that has been enhanced by an additional ten months of the Hubble’s journey through the ‘dark universe’.
Hubble telescope is “beyond repair”.
When the Hubble Space Telescope was launched in 1990, it was to be the first astronomical observatory to look at distant objects in the cosmos. But a few unfortunate events since that time have forced the observatory to the brink of obsolescence.  Most of the telescope’s optics and electronics have been damaged from weather, radiation, or mechanical failures. In some cases, all of the telescope’s cameras and computer systems have been destroyed. Many of these disasters were caused by solar storms, and the telescope’s backup computer systems are likely to be affected by the same.  The Hubble Telescope has been plagued by numerous space-based solar storms since its launch.  The telescope’s backup computer system had to be brought online in 2004, after a backup computer was destroyed in orbit in 2003.  During a December 2005 solar storm that caused a total loss of power to the telescope, Hubble managed to see some images of a distant planetary system.  A total loss of power in October 2006 forced the telescope to temporarily stop using its backup Computer in the middle of a survey of the cosmos.  During a total loss of power in December 2006, Hubble was temporarily unable to take images of a distant galaxy.  It is expected that the telescope will have to be redesigned with the help of NASA.  A total loss of power in December 2007 has caused the telescope to temporarily shut down.  A total loss of power in November 2009 has caused the telescope to temporarily shut down.  Hubble is still suffering from a lack of power and the impact of the recent 2007 solar storm on its backup computer system.  The Hubble Telescope has had its backup computer kept alive for three months, but that time has come to an end.  During a total loss of power in October 2013, Hubble was unable to take images of a distant galaxy.  A total loss of power in September 2015 has caused the telescope to temporarily shut down.
How to Backup a Simulator for Planet Formation?
A recent study by NASA’s Jet Propulsion Laboratory showed that it was possible to perform simulations in orbit by modifying a model of a computer’s hard drive. The method is called “reversibility” and is based on how hard drives physically change their stored information in the course of normal operation. One limitation to the method, however, is that it can only work with a model of how the hard drive’s information is actually stored in the hard drive when it is installed in the computer. After the hard drive has been installed, an external hard drive and a floppy disk can be used as well. The simulations are performed by running the simulator on the hard drive. This type of simulation is called “reversibility” because the model of the hard drive storage is reversed when the hard drive is installed, in the sense that the hard drive’s information is not stored in the normal way, but in the reversed order.
Before discussing how to backup a simulator for Planet Formation, the following information on how to backup a computer that has lost data is relevant. The computer can be any type of computer, but the simulator will be used to discuss a disk backup method, since most of the information will be contained in the program used to backup the simulator.
The computer has lost all or most of its information. The computer system will be called a “virtual computer” in this article, since the simulator is stored as data and accessed using programmatic means.
The data that is lost will be part of a “virtual computer”, which it is often a better name for a “virtual machine”. This should not be confused with “virtual machine”, which refers to a software program running directly on the hardware of a computer. The term virtual computer refers to a computer that is a copy of a “real” computer, not an abstraction over several different possible “reals”.
The information that the virtual computer lost cannot be restored any longer any more.
The James Webb Telescope is not Hubble’s successor.
A new telescope, to be named JWST, will change the way we view the cosmos, and its discovery and development will affect the future of the scientific study of the cosmos and our own society. Such is the promise of JWST, a telescope that, for the first time, will have the power and the precision to study a star in a way we can no longer see in any other way.
This is an excerpt of a speech I gave at the JWST Symposium recently. The full paper is available here.
The James Webb Telescope (JWST) will be the culmination of the efforts of astronomers to build the world’s first space telescope. Its name gives away its purpose, but it is also a fitting summation of the science it will measure and investigate– a cosmos we will want to study and that we are about to see.
The James Webb Telescope will be an observatory that will image the entire sky in high-resolution. Most of the light from distant objects comes from stars, so in order to build the instrument, astronomers will try to see the stars hidden by our own galaxies. This involves a telescope called the James Webb Space Telescope, which will be a collaboration between NASA, the European Space Agency, and Astrophysics Research Institute of Japan, with the European Space Agency as the overall partner.
The telescope will not be limited to a fixed location; the observatory will be able to scan the sky over large areas and the same telescope will be able to observe the entire universe (as seen by all observers) from one or a few observatory sites. The telescope will take more than 15 years, but even during that time it will discover many objects of astrophysical interest that are already known.
Scientists who are working on JWST will contribute to the mission. The entire process will be a collaboration between science teams and astronomy students. An early project, called Deep Impact, will seek to study how stars are formed from the debris of supernovae explosions. An important collaboration is with Japan’s Keck telescope.