jwst Archives

April 8, 2022April 8, 2022 by Nancy Atkinson

It’s Been Three Months in Deep Space, and Webb’s Mid-Infrared Instrument is Still Cooling Down

The James Webb Space Telescope continues to cool down out at its location at Lagrange Point 2, about 1.5 million kilometers from Earth. Since JWST is an infrared telescope, it needs to operate at extremely low temperatures, less than 40 K (-223 degrees Celsius, -369.4 degrees Fahrenheit). But one instrument needs to be even colder.

To operate at peak efficiency, Webb’s Mid-Infrared Instrument (MIRI) must be cooled to a chilly 7 K (-266 C, -447 F). And it will need a little help to reach those frigid temps.

April 8, 2022April 8, 2022 by Matt Williams

A New Record for the Most Distant Galaxy, Seen Just 300 Million Years After the Big Bang

Three-color image of HD1, the most distant galaxy candidate to date, created using data from the VISTA telescope. The red object in the center of the zoom-in image is HD1. Credit: Harikane et al.

Since the Renaissance astronomer Galileo Galilee first studied the heavens using a telescope he built himself, astronomers have been pushing the boundaries of what they can observe. After centuries of progress, they have been able to study and catalog objects in all but the earliest periods of the Universe. But thanks to next-generation instruments and technologies, astronomers will soon be able to observe the “Cosmic Dawn” era – ca. 50 million to billion years after the Big Bang.

In recent years, astronomers have made discoveries that preview what this will be like, the most recent of which is the galaxy candidate known as HD1. This galaxy is about 13.5 billion light-years from Earth (32.2 billion light-years in terms of “proper distance“), making it the farthest ever observed. This discovery implies that galaxies existed as early as 300 million years after the Big Bang, a finding which could have drastic implications for astronomy and cosmology!

March 27, 2022March 27, 2022 by Brian Koberlein

NASA's Upcoming SPHEREx Mission Will map the Entire Universe in Infrared Every 6 Months

Illustration of the SPHEREx satellite. Credit: NASA/JPL-Caltech

The universe is cold and dark. And yet, within the dark, there is a faint glow of warmth. Across the sky, there are objects that emit infrared light, similar to the light that warms your hands near a campfire. By observing this light, astronomers can see the cosmos in a way that looks very different from that seen by our eyes.

March 19, 2022March 19, 2022 by Matt Williams

Machine Learning Will be one of the Best Ways to Identify Habitable Exoplanets

Illustration of Kepler-186f, a recently-discovered, possibly Earthlike exoplanet that could be a host to life. Scientists could use this one or one like it to measure planetary entropy production as a prelude to exploration. (NASA Ames, SETI Institute, JPL-Caltech, T. Pyle)

The field of extrasolar planet studies is undergoing a seismic shift. To date, 4,940 exoplanets have been confirmed in 3,711 planetary systems, with another 8,709 candidates awaiting confirmation. With so many planets available for study and improvements in telescope sensitivity and data analysis, the focus is transitioning from discovery to characterization. Instead of simply looking for more planets, astrobiologists will examine “potentially-habitable” worlds for potential “biosignatures.”

This refers to the chemical signatures associated with life and biological processes, one of the most important of which is water. As the only known solvent that life (as we know it) cannot exist, water is considered the divining rod for finding life. In a recent study, astrophysicists Dang Pham and Lisa Kaltenegger explain how future surveys (when combined with machine learning) could discern the presence of water, snow, and clouds on distant exoplanets.

March 19, 2022March 19, 2022 by Matt Williams

Wondering About the 6 Rays Coming out of JWST's Test Image? Here's why They Happen

At the Space Telescope Science Institute (STSI) in Baltimore, Maryland, NASA engineers are busy aligning the mirrors and instruments on the James Webb Space Telescope (JWST). In the meantime, the mission team has provided us with another glimpse of what this observatory – a successor to the venerable Hubble Space Telescope – will see once it is fully operational. The latest teaser is a “telescope alignment evaluation image” of a distant star that looks red and spiked!

March 17, 2022March 17, 2022 by Nancy Atkinson

ESA’s Gaia Just Took a Picture of L2 Neighbor JWST

Oh, hello there new neighbor! In February, the Gaia spacecraft took a picture of its new closest companion in space at the second Lagrangian point, the James Webb Space Telescope.

Gaia is an optical telescope that is mapping out our galaxy by surveying the motions of more than a thousand million stars. Astronomers for the mission realized that once JWST reached L2, it would be in Gaia’s field of view. It spied JWST when the two spacecraft were a million km apart.

March 16, 2022March 17, 2022 by Nancy Atkinson

Webb has Now Taken the Sharpest Image the Laws of Physics Allow

A JWST engineering image of the star 2MASS J17554042+6551277, uses a red filter to optimize visual contrast. Credits: NASA/STScI

Engineers and scientists for the James Webb Space Telescope have completed two more steps in the telescope’s primary mirror alignment process, and in a briefing today, officials said JWST’s optical performance appears to be better than even the most optimistic predictions.

The team released a new engineering image, showing the star 2MASS J17554042+6551277 in crisp clarity. This image demonstrates that all 18 mirror segments have been precisely aligned to act as one giant, high-precision 6.5-meter (21.3-foot) primary telescope mirror.

February 25, 2022February 26, 2022 by Nancy Atkinson

Webb turns those 18 separate star images into a single unified star. Next comes even better focus.

During this phase of alignment known as Image Stacking, individual segment images are moved so they fall precisely at the center of the field to produce one unified image instead of 18. In this image, all 18 segments are on top of each other. After future alignment steps, the image will be even sharper. Credit: NASA/STScI

It’s coming together! Engineers for the James Webb Space Telescope have now completed two more phases of the seven-step, three-month-long mirror alignment process. This week, the team made more adjustments to the mirror segments along with updating the alignment of its secondary mirror. These refinements allowed for all 18 mirror segments to work together — for the first time — to produce one unified image.

February 23, 2022April 8, 2022 by Nancy Atkinson

Here’s Exactly how Engineers Are Aligning JWST’s Segmented Mirrors

This early Webb alignment image, with dots of starlight arranged in a pattern similar to the honeycomb shape of the primary mirror, is called an “image array.” Credit: NASA/STScI/J. DePasquale

Engineers for the James Webb Space Telescope are in the midst of an intricate, three-month-long process of aligning the telescope’s 18 separate mirror segments to work together as one giant, high-precision 6.5-meter (21.3-foot) primary telescope mirror.

This process, called phasing, began in early February and includes seven different steps, which goes from taking the mirrors’ initial placements after they were deployed to doing a “coarse” and then “fine” alignment, and then making sure the mirror works with all four of Webb’s instruments and their various fields of view.

February 21, 2022February 21, 2022 by Scott Alan Johnston

James Webb Might be Able to Detect Other Civilizations by their Air Pollution

The James Webb Space Telescope (JWST), launched last December, has been slowly powering up its instruments and unfurling its sunshield, and is now in the process of aligning its mirrors in preparation for operation. Within a few months, the most powerful space telescope ever built is going to set its sights on the stars. Astronomers are hoping that what JWST sees will change the way we understand our universe, just as the Hubble Space Telescope did decades before.

One tantalizing capability that JWST offers that Hubble could not is the opportunity to directly image planets orbiting distant stars, and maybe, just maybe, detect signs of life.