If you wake up early enough on Saturday, you’ll be greeted with a spectacle of science and engineering: the launch into orbit of the James Webb Space Telescope.
The telescope is a joint project of NASA, the European Space Agency and the Canadian Space Agency and will be the most powerful observatory ever sent into space. Astronomers have waited decades as budgetary and technical delays have delayed the completion and launch of the Webb.
But on Christmas morning, she and the rest of humanity will come one step closer to witness the beginning of its spacecraft science mission. Here’s what you need to know.
When is the launch and how can I watch it?
The telescope is expected to lift off from a European-operated spaceport in French Guiana on the coast of South America at 7:20 a.m. ET on Saturday. The launch window lasts 32 minutes, until 07:52 AM, in case there are any last minute missile checks or short pauses in the countdown. A longer delay means the launch would be delayed until that same time on Sunday.
NASA, the telescope’s main funder, will host a live stream on its YouTube channel starting at 6 a.m., and on its main Twitter and Facebook accounts starting at the same time. Agency officials will comment with astronomers ahead of the launch. You can also register for a virtual launch event.
If you prefer to watch the launch in French or Spanish, the European Space Agency will also be streaming the launch in those languages.
Why is the Webb telescope so important to scientists?
The Webb telescope was designed to investigate a pivotal piece of early cosmic history known to astronomers as the Dark Ages.
Cosmologists suspect that the first stars appeared when the universe was only about 100 million years old. (Today, it is 13.8 billion years old.) The farthest and earliest galaxy seen by astronomers, using the Hubble Space Telescope, dates back to when the universe was older, 400 million years after the Big Bang. What happened during those intervening 300 million years when the universe took off, how the Big Bang turned into a sky full of constellations and life, is a mystery.
The telescope will also help astronomers to better study supermassive black holes at the center of galaxies and planets orbiting other stars in our galaxy.
To achieve these scientific observations, the Webb telescope relies on a primary mirror with a diameter of 6.5 meters, compared to the mirror on the Hubble, which is 2.4 meters. That gives it about seven times the light-gathering power and thus the ability to see further into the past.
Another crucial difference is that it is equipped with cameras and other instruments that are sensitive to infrared radiation or ‘heat’. The expansion of the universe causes light that would normally be in visible wavelengths to shift to longer infrared wavelengths that are normally invisible to human eyes.
Engineers along the way had to invent 10 new technologies to make the telescope more sensitive than the Hubble. Over-optimistic planning forecasts, incidental development accidents and disorganized cost reporting dragged the timeline into 2021, pushing total costs to $10 billion.
Why is the telescope launching from French Guiana?
The European Space Agency does not have an orbital launch site in any of its member states on the European landmass. Instead, it is usually launched from a spaceport in Kourou, French Guiana.
The use of the Kourou launch site is part of the consortium’s €300 million contribution to the Webb mission. NASA signed an agreement with ESA in 2003 to launch Webb on an Ariane 5 rocket from Arianespace, a French rocket maker.
Turn your phone into a personal planetarium.
To understand the observing powers of the James Webb Space Telescope and how it will aid astronomers in their research, try these two augmented reality experiences in your own space with a smartphone logged into Instagram.
The first shows you where in space and time the Webb will look with a 3D map of the observable universe. It plots some of the spacecraft’s early targets, which may include Earth-like exoplanets and the earliest known galaxies. Try it here on Instagram.
The second augmented reality experience shows the Webb getting a visual boost from the power of gravity lenses.
Place a virtual black hole in your space and see how it behaves like a magnifying glass on your environment. This same technique will help astronomers study the early Universe. Try it here on Instagram.
Noah Pisner reporting contributed.
