The largest telescope to be put into orbit is a bit of a tricky question, as it depends on how you define "largest."

Here are two contenders, based on different interpretations:

1. Largest by Primary Mirror Diameter:

* The James Webb Space Telescope (JWST) has a primary mirror measuring 6.5 meters (21 feet) in diameter. This makes it the largest telescope ever launched into space. It's also the most powerful telescope ever sent into space, designed to observe the first stars and galaxies.

2. Largest by Collecting Area:

* The Very Large Telescope Interferometer (VLTI) isn't technically a single telescope in orbit. It's a network of four 8.2-meter telescopes located in Chile that can be combined to act as a single, giant telescope with an effective diameter of up to 200 meters. This gives the VLTI the largest collecting area of any telescope in the world, making it incredibly powerful for studying faint objects.

So, depending on your criteria, the James Webb Space Telescope holds the record for largest mirror diameter, while the Very Large Telescope Interferometer boasts the largest collecting area.