A planetary nebula is seen against the blackness of space with points of star light behind it. The credit is given to NASA, CSA, and theSTScI.
Over the course of 26 years, NASA scientists have pleaded for three things: patience, time and money. It was in 1996 that the first proposal for a next- generation space telescope was made. They promised that the telescope would be ready to launch by 2007, and that it would cost $500 million.
That wasn't the way it worked out. There was a forecast for a launch in 2007, but it wasn't until Christmas Day 2021. It grew to $10 billion. The images from the new telescope would be amazing.
That promise was fulfilled this morning. In a media briefing at the Goddard Space Flight Center in Greenbelt, Md., NASA unveiled four new images captured by the James Webb Space Telescope that are flat-out dazzling. At a White House press conference yesterday, NASA Administrator Bill Nelson revealed a gobsmacking picture of a swarm of thousands of galaxies, including the most distant ones ever seen in the infrared spectrum.
Biden said that the images would remind the world of America's capabilities. There is nothing we can't do. He said the telescope symbolises the spirit of American ingenuity.
There are objects that most people outside of the astronomy community have never heard of that will now become part of the history of the universe. They are also included in SMACS-0723.
The Carina Nebula is located 7,600 light years away from Earth.
WASP-96b is 1,150 light years away from Earth.
The cloud of gas around the dying star is half a light year wide.
The first image of Stephan's Quintet was taken in 1787.
The smallest object the telescope imaged, the exoplanet WASP-96b, will probably cause the most excitement. Until now, exoplanets were only visible in one of two ways: the transit method, in which a planet passes in front of a star, and the radial velocity method, in which a planet passes in front of a star.
Astronomers have never been able to see the planet itself because of the blinding glare of its parent star. The image of the small body would be washed out. The image of WASP-96b is historic because it's the first time that an image of an exoplanet has been seen.
VP Harris said yesterday that we are entering a new phase of scientific discovery with these photos. President Biden said that the images offered a new window into the history of our universe.
The location of the telescope in space makes it like no other telescope has been built before. The Hubble Space Telescope was launched in 1990 and circles the Earth in an altitude of 547 km above the atmosphere. Hubble works in a conventional way, meaning it has a conventional look. It needs to protect its mirrors from stray light from the sun, the Earth and other objects that it isn't observing.
The wavelength of light beyond the visible spectrum that is measured by the telescope is called the IR spectrum. Dust and gas in deep space make it impossible for Hubble to see the light years away. The interference is cut through by the IR light. In order to work, Hubble needs to be protected from stray heat as well as stray light. The telescope needs to be kept extremely cold. It makes for some strange architecture.
The main mirror is made of 18 hexagonal segments and can be adjusted in seven different axes with a precision down to the nanometer. Hubble's main mirror would trap heat and expose the mirror to space. It doesn't go around the Earth where the constant day-night cycle would cause its own temperature changes. It is located 1.6 million km from the planet, in a spot in space where the gravity of the Earth and the sun cancel each other out.
The heat of the sun and even the remote Earth and moon make it necessary for the mirror to fly atop a protective sun-shield. The sun shield is made of five layers of kapton, a foil-like film with a thickness no greater than that of a human hair. The temperature on the side which faces the sun is about 120o C. The inner layer is close to the mirror. The faint, invisible heat from deep space can register on the telescope's mirror and be translated into visible images.
It is an observing machine, but it is also a time machine. Since images from distant objects take a long time to reach us, the farther into space a telescope can look, the more it can see. The image we see of a galaxy 13.6 billion light years away isn't an image of how it looks today, but how it looked 13.6 billion years ago The Hubble space telescope can see a maximum of 13.4 billion light years away, and while the 200 million light-year advantage of the Webb doesn't seem like much, it's in fact huge. Telescopes have been blind to a great deal of what happened in that time period.
Scott Friedman, an astronomer with the Webb team, said in a conversation with Time last year that the difference between what Hubble and Webb see is not like comparing someone who is 70 years old to someone who is 71 years old. It is similar to comparing a baby who is one day old to a baby who is one year old.
Astronomers around the world are clamoring with proposals to book time on the Webb to study objects of interest over the next few years. It's for the dazzle today. The beauty of the universe can be seen. The curtain is being pulled on all of that.
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