Astronomy Ideas on Borrowed Time?

Posted on by onespaceman2000
Image (Credit): The position of our Sun as it orbits the Milky Way’s center. (Stefan Payne-Wardenaar)

A recent Big Think story, “5 Consensus Ideas in Astronomy That Might Soon be Overturned,” comes as a good time as we reach further into space and back into time using the James Webb Space Telescope (JWST) and contemplate other telescopes that should come online shortly.

The story highlights these five ideas:

  • Dark energy is a cosmological constant;
  • Stars predate black holes;
  • Jovian planets protect terrestrial ones;
  • Most of the galaxy is uninhabitable; and
  • Globular clusters are planet-free.

For instance, regarding the uninhabitable areas of the galaxy, the Big Think story states:

Among its many discoveries, the ESA’s Gaia mission has found that the Milky Way galaxy not only has a warp to its galactic disk, but that the warp in the disk precesses and wobbles, completing a full rotation for roughly every three revolutions of the Sun [shown in yellow above] around the galactic center. Most astronomers assume that regions with too many stellar cataclysms in them, like the centers of galaxies, may be completely uninhabitable. But this picture is far from certain.

It is worth reading through the list and keeping these ideas in mind, and then following the JWST stories as they unfold. I bet you will be able to make a much longer list as old consensus ideas come apart and new ideas quickly follow.

The JWST’s First Image of an Exoplanet

Posted on by onespaceman2000
Image (Credit): Exoplanet HIP 65426 b in different bands of infrared light, as seen from the JWST: purple shows the Near-Infrared Camera (NIRCam) instrument’s view at 3.00 micrometers, blue shows the NIRCam instrument’s view at 4.44 micrometers, yellow shows the Mid-Infrared Instrument (MIRI) instrument’s view at 11.4 micrometers, and red shows the MIRI instrument’s view at 15.5 micrometers. These images look different because of the ways the different Webb instruments capture light. A set of masks within each instrument, called a coronagraph, blocks out the host star’s light so that the planet can be seen. The small white star in each image marks the location of the host star HIP 65426, which has been subtracted using the coronagraphs and image processing. The bar shapes in the NIRCam images are artifacts of the telescope’s optics, not objects in the scene. (NASA/ESA/CSA, A Carter (UCSC), the ERS 1386 team, and A. Pagan (STScI))

It was only a matter of time, but even so it was pretty quick. The James Webb Space Telescope (JWST) has taken a direct image of an exoplanet. HIP 65426 b, a gas giant that lies 355 light-years away, is from 15 to 20 million years old and about 6 to 12 times the mass of Jupiter. This gas giant is also about 100 times farther from its host star than Earth is from the Sun, allowing the JWST to see the exoplanet’s light separate from its sun.

This is not the first direct image of an exoplanet. The Hubble Space Telescope has also captured images of exoplanets. For instance, in 2008 an astronomer using Hubble images reported on Fomalhaut b, a Jupiter-mass exoplanet that is about 25 light-years away and approximately 200 million years old. It takes close to 872 years for the exoplanet to orbit its sun. Fomalhaut b will most likely be another target for JWST in the near future.

Image (Credit): Hubble Space Telescope optical image from 2006 showing the belt of dust and debris (bright oval) surrounding the star Fomalhaut and the planet (inset) that orbits the star every 872 years and sculpts the inner edge of the belt. A coronagraph (center) on the Advanced Camera for Surveys blocks out the light of the star, which is 100 million times brighter than the planet. (Paul Kalas/UC Berkeley, NASA, ESA)

Podcast: Scientists Discuss the JWST

Posted on by onespaceman2000

It is worth checking out the BBC’s Sky at Night podcast if you want to follow the stars or just listen to astronomers discussing the night sky. Two recent episodes in particular, both related to the James Webb Space Telescope (JWST), should be on your podcast list.

  • How James Webb Space Telescope Observes the Universe (broadcast on August 26, 2022): Dr Pamela Klaassen, an instrument scientist, reveals the science behind how JWST studies the cosmos, what its images show us, and the secrets it might uncover. She also discusses her work studying very large stars. Finally, the discussion covers the Square Kilometre Array Organization and how this brand new ground-based observatory will work in tandem with the JWST to unlock the secrets of the Universe.
  • Exploring Exoplanets with JWST (broadcast on August 22, 2022): Dr Hannah Wakeford from the University of Bristol is part of an international collaboration of exoplanet hunters looking to see how the JWST can reveal the secrets of worlds orbiting stars beyond our solar system. One exoplanet priority for the JWST discussed during the episode is WASP-39b, the results of which were recently shared with the public.

Exoplanet WASP-39b Found to Have Carbon Dioxide in its Atmosphere

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Image (Credit): Comparison of exoplanet WASP-39b to Earth and Jupiter. (wasp-planets.net)

Yesterday, the University of Maryland reported that the James Webb Space Telescope (JWST) has detected carbon dioxide in the atmosphere of exoplanet WASP-39b, a gas giant about 700 light-years away. This is the first time carbon dioxide has been detected on a planet outside of our solar system.

Eliza Kempton, an associate professor of astronomy at the University of Maryland, stated:

The reason we hadn’t been able to definitively identify CO2 in the atmosphere of WASP-39 b previously was that we never had a telescope that could produce spectra across the right wavelength range…This discovery shows us that Webb is delivering on its promise of being a transformational facility for astronomical observations.

Natalie Batalha of the University of California at Santa Cruz, who leads the team, added:

Detecting such a clear signal of carbon dioxide on WASP-39 b bodes well for the detection of atmospheres on smaller, terrestrial-sized planets.

Again, the JWST is showing it is worth its weight in gold (see note below) as it peers through the universe and quickly observes things we only speculated about earlier.

Note: In fact, the JWST weights 14,300 lbs here on Earth, or 228,800 ounces. Today, gold costs $1,763.00 per ounce. So if the JWST was made of solid gold, it would cost about $403 million. Given that the JWST actually costed $10 billion to build and launch, in weight it is 25 times more valuable than gold.

Pic of the Week: A New View of Jupiter

Posted on by onespaceman2000
Image (Credit): Jupiter as captured by the JWST. (NASA, ESA, CSA, Jupiter ERS Team; image processing by Ricardo Hueso (UPV/EHU) and Judy Schmidt)

This week’s image once again comes from the new James Webb Space Telescope (JWST), but instead of peering outside of our solar system, it is looking around closer to home. The image above of Jupiter is an amazing shot that shows the planet in all its glory – violent storms, glowing auroras, delicate rings, and orbiting moons. The particulars are labeled in the same image below.

The image came from the JWST’s Near-Infrared Camera (NIRCam), which NASA notes has:

…three specialized infrared filters that showcase details of the planet. Since infrared light is invisible to the human eye, the light has been mapped onto the visible spectrum. Generally, the longest wavelengths appear redder and the shortest wavelengths are shown as more blue. Scientists collaborated with citizen scientist Judy Schmidt to translate the Webb data into images. 

This is a whole new way to see our neighborhood worlds as well as the worlds many light years away.

Image (Credit): Jupiter as captured by the JWST with all of the key areas labeled. (NASA, ESA, CSA, Jupiter ERS Team; image processing by Ricardo Hueso (UPV/EHU) and Judy Schmidt)