89. James Webb Space Telescope Launch & Merry Late Christmas

That‘s Cool News | A weekly breakdown of positive Science & Tech news.

Launch Day From Nasa.gov:

• NASA’s James Webb Space Telescope launched at 7:20 a.m. EST Saturday (Dec. 25th) on an Ariane 5 rocket from Europe’s Spaceport in French Guiana, South America.
  • A joint effort with ESA (European Space Agency) and the Canadian Space Agency,
• The Webb observatory is NASA’s revolutionary flagship mission to seek the light from the first galaxies in the early universe and to explore our own solar system, as well as planets orbiting other stars, called exoplanets.
• Ground teams began receiving telemetry data from Webb about five minutes after launch.`
• Approximately 30 minutes after launch, Webb unfolded its solar array, and mission managers confirmed that the solar array was providing power to the observatory.
• Engineers and ground controllers will conduct the first of three mid-course correction burns about 12.5 hours after launch
  • Firing thrusters to maneuver the spacecraft on an optimal trajectory toward its destination in orbit about 1 million miles from Earth.
  • Sun-Earth Lagrange Point 2 (L2)
• The world’s largest and most complex space science observatory will now begin six months of commissioning in space. At the end of commissioning, Webb will deliver its first images.
• Webb’s program director at NASA Headquarters, Gregory L. Robinson, talks about the launch:
  • “The launch of the Webb Space Telescope is a pivotal moment – this is just the beginning for the Webb mission … Now we will watch Webb’s highly anticipated and critical 29 days on the edge. When the spacecraft unfurls in space, Webb will undergo the most difficult and complex deployment sequence ever attempted in space. Once commissioning is complete, we will see awe-inspiring images that will capture our imagination.”

The Time Machine from The Conversation:

• Benefit of the James Webb Telescope, and most space telescopes, is that they are time machines.
  • Any light that hits a telescope (i.e. image) you will be looking at old light. For instance looking at an object 10,000 light years away if you have an image you will be looking at 10,000 years in the past.
    • Light would take 10,000 years to reach Earth.
  • The further out in space astronomers look, the further back in time we are looking.
    • JWST is trying to look FAR back.
• JWST is specifically designed to try to look at light from the end of the Dark Ages by detecting the faint infrared light of the earliest stars or galaxies.
  • Dark Ages:
    • Around 400,000 years after the Big Bang, the universe was 10 million light years across and the temperature had cooled to 5,500 F (3,000 C).
    • The universe would have been glowing dull red like a giant heat lamp.
    • As the expanding universe became bigger and colder, the high energy particles thinned out and everything faded to black.
  • The Dark Ages ended when gravity formed the first stars and galaxies that eventually began to emit the first light.
• Compared to massive, bright galaxies of today, the first objects (i.e stars & galaxies) were very small.
  • Additionally, due to the constant expansion of the universe, they’re now tens of billions of light years away from Earth.
• This leads to the why infrared is important:
  • As the universe expands, it continuously stretches the wavelength of light traveling through it. That leads to a “redshift.”
  • Light shifts from shorter wavelengths – like blue or white light – to longer wavelengths like red or infrared light when stretched.
  • Therefore, by the time light emitted by an early star or galaxy 13 billion years ago reaches any telescope on Earth, it has been stretched by a factor of 10.
    • It arrives as infrared light!
• Comparing it to Hubble, JWST has a 15 times wider field of view on its camera, collecting six times more light and its sensors are tuned to be most sensitive to infrared light.

• How will Data be collected?

• The strategy will be to stare deeply at one patch of sky for a long time, collecting as much light and information from the most distant and oldest galaxies as possible.

What to look for in the next 6 months?

• JWST needs to get to the orbiting point
• Needs to unroll the sunshield system
  • Has 140 release mechanisms, 70 hinge assemblies, 400 pulleys, 90 cables and eight deployment motors, all of which need to perform correctly to get the five thin membranes extended
• Deploying the 18 mirror segments
  • According to Project Scientist Jonathan Gardner, "One of our scientists calculated that we move those mirrors literally slower than grass grows as we're lining them up so incredibly precisely,"
• Regular science operations are expected to begin in the summer of 2022