Hubble Space Telescope

Context:

NASA reports trouble with the Hubble Space Telescope. The telescope has been down for the past few days. The problem is a payload computer that has stopped working. 

About the Hubble Space Telescope: 

• Hubble is named after Edwin P. Hubble. He was an astronomer.
• The Hubble Space Telescope was launched into low Earth orbit in 1990 and remains in operation.
• It was not the first space telescope, but it is one of the largest and most versatile, renowned both as a vital research tool and as a public relations boon for astronomy. The
• Hubble features a 2.4 m (7 ft 10 in) mirror, and its four main instruments observe in the ultraviolet, visible, and near-infrared regions of the electromagnetic spectrum. Hubble’s orbit outside the distortion of atmosphere of Earth allows it to capture extremely high-resolution images with substantially lower background light than ground-based telescopes. It has recorded some of the most detailed visible light images, allowing a deep view into space. Many Hubble observations have led to breakthroughs in astrophysics, such as determining the rate of expansion of the universe.
• The Hubble telescope was built by the United States space agency NASA with contributions from the European Space Agency
• Hubble is the only telescope designed to be maintained in space by astronauts. Five Space Shuttle missions have repaired, upgraded, and replaced systems on the telescope, including all five of the main instruments.

Features of Hubble Space Telescope

Based on its construction and the elementary parts which have constituted its functions, the Hubble telescope has made several observations that were unimagined for the researchers. 

Discussed below are few of the major features of Hubble Space Telescope:

• At one time, five scientific instruments can be accommodated in Hubble, along with it, the Fine Guidance Sensors can be installed in the telescope
• Hubble is 43.5 feet long, and 14 feet wide, and weighs about 27,000 pounds
• The instruments which have been installed in Hubble include:

• Camera – Advanced Camera for Surveys (ACS) and the Wide Field Camera 3 (WFC3) are the two primary cameras which have been installed to click images of the comos
• Spectrographs – The science of breaking light down to its components is called spectrography, and this device performs a similar function
• Interferometers – A total of three interferometers are aboard Hubblewhich are called Fine Guidance Sensors and are useful in measuring the relative positions and brightnesses of stars
• Past Instruments – Since the telescope has been serviced 5 times until 2020. The instruments which were a part of Hubble, but have now been replaced include: High Speed Photometer, Faint Object Camera & Spectrograph, Goddard High Resolution Spectrograph, and Wide Field and Planetary Camera 2
• Current Instruments – The instruments which are still a part of the telescope (as in 2020), includes 

• Advanced Camera for Surveys (ACS)
• Cosmic Origins Spectrograph (COS)
• Space Telescope Imaging Spectrograph (STIS)
• Wide Field Camera 3 (WFC3)
• Fine Guidance Sensor (FGS)
• Near Infrared Camera and Multi-Object Spectrometer (NICMOS)

What Makes Hubble Different From Telescopes on Earth?

The mixture of gases that surround a planet is called its atmosphere. Earth’s atmosphere changes and blocks some of the light that comes from space. Hubble flies around, or orbits, high above Earth and its atmosphere. So, Hubble can see space better than telescopes on Earth can. Hubble is not the kind of telescope that you look through with your eye.  Hubble uses a digital camera. It takes pictures like a cell phone. Then Hubble uses radio waves to send the pictures through the air back to Earth.

What Is the Future for Hubble?

In 2009, astronauts flew to Hubble on the space shuttle. This was the fifth time astronauts went to fix Hubble. They put new parts and cameras in the telescope. So, it is working very well. Hubble will not be fixed again. In 2020, Hubble turned 30 years old. It still takes beautiful pictures of objects in space.

NASA is building another space telescope. It is called the James Webb Space Telescope. It will be bigger than Hubble. Webb will not orbit Earth as Hubble does. Webb will orbit the sun in a spot on the other side of the moon. The Webb telescope will be able to see a different kind of light than the light Hubble sees. Webb will help NASA see even more of the universe.

Hubble discoveries | a timeline

1990 | The Hubble Space Telescope is launched, after almost twenty years of planning.

1993 | When Hubble was first launched, a mistake with its mirror caused a large blurring effect that severely hampered its ability to complete ground breaking astronomy. The first servicing mission to Hubble had astronauts on the Endeavour space shuttle fix a flaw in Hubble’s mirror, bringing its optics to the stunning level of detail we see today.

1994 | Hubble witnessed a rare cometary impact, taking snapshots of a huge plume of debris left behind Comet Shoemaker-Levy 9 after it collided with Jupiter. Hubble also provided conclusive evidence for the existence of Supermassive Black Holes in the centres of galaxies by observing the galaxy M87.

1995 | Hubble took the famous photo of the Eagle Nebula which was later named ‘pillars of creation’.

2001 | Hubble measured the elements in the atmosphere of the exoplanet HD 209458b.

2004 | The Hubble Ultra Deep Field was released allowing astronomers to look even further back in the time of the cosmos.

2005 | Hubble photographed two previously unknown moons orbiting Pluto.

2007 | Hubble observations showed that the dwarf planet Eris was bigger than Pluto. Hubble also assisted the production of a 3D-map showing the distribution of dark matter in the Universe.

2008 | Hubble took a picture of the exoplanet Formalhaut b, the first visual image of an exoplanet. In the same year Hubble found organic molecules on an extrasolar planet and the telescope’s 100 000th orbit around Earth was celebrated.

2010 | Hubble images revealed distant galaxies with likely redshifts (a measure of distance used in cosmology) greater than 8, showing the Universe as it was when it was less than a tenth of its current age. Hubble also photographed a never-before-seen evidence of a collision between two asteroids.

2011 | Hubble made its millionth observation, a spectroscopic analysis of the exoplanet HAT-P-7b. The 10,000th scientific paper using Hubble data was published.

2012 | Images taken by Hubble showed seven primitive galaxies from a distant population that formed more than 13 billion years ago. The images showed the galaxies as they were when the Universe was less than 4 percent of its present age. Later in the year that record was broken when Hubble discovered an object from when the Universe was only 3 percent of its present age, only 470 million years after the Big Bang.

2013 | Hubble was used to determine for the first time the true colour of a planet orbiting another star and found water vapour erupting off the surface of Jupiter’s moon Europa.

2014 | Hubble became the first telescope ever to observe an asteroid disintegrating and revealed the most detailed weather map for an exoplanet ever.

2015 | Hubble observed, for the first time, the effect of gravitational lensing on a distant exploding star, where the powerful gravity of a foreground galaxy acts like a cosmic magnifying glass, enhancing and splitting the image into a cross-shaped pattern of light.

Source: Times of India