Archives

All posts by admin

The Solar Eclipse on Oct 14

Posted by admin on August 30, 2023
Posted in: First Friday Astronomy, Public Outreach. Tagged: .
Artist’s depiction of the annular solar eclipse.

On the morning of Saturday, Oct 14, the Sun will transform into the eye of Sauron, a dark circle wreathed in otherworldly flame. Sauron’s gaze will cross the surface of the Earth from the Pacific Ocean, through the Pacific-Northwest and Southwest, and down the spine of Central America, before fizzling out of the east coast of Brazil. Though not as dramatic as total eclipses, annular eclipses like this one are more rare, owing to the eccentricities of orbital mechanics. And the same celestial forces have also woven a tapestry of occultations connecting the Oct 14 eclipse back to the founding of the Cologne Cathedral, a turning point in modern science, and the dawn of a new age.

Continue Reading

Dark Stars and Dark Matter

Posted by admin on August 1, 2023
Posted in: First Friday Astronomy, Public Outreach. Tagged: , , .
This is a reprint of a blog post originally run Jun 2022.
Gravitational lensing of distant galaxies observed by Hubble. From https://www.nasa.gov/content/discoveries-highlights-shining-a-light-on-dark-matter.

Although our current understanding of gravity, the theory of general relativity, arose only one hundred years ago, scientists were speculating about exotic gravitational effects going back to before the word “scientist” even existed. Today, astronomers employ gravity in a variety of ways to study the cosmos, to look for planets outside our solar system and even to weigh some of the largest celestial bodies in existence. These measurements have shed light on some of the darkest of astronomical mysteries.

Continue Reading

How Will JWST Study Exoplanets?

Posted by admin on July 6, 2023
Posted in: First Friday Astronomy, Public Outreach. Tagged: , , .

From https://webbtelescope.org/resource-gallery/articles. (This is a slightly updated reprint of an article originally run Nov 2021.)

An artist’s concept of the Webb Space Telescope. From https://solarsystem.nasa.gov/missions/james-webb-space-telescope/in-depth/.

NASA’s James Webb Space Telescope (JWST), scheduled to launch on December 18, will primarily use its spectrographs – specialized instruments that capture and spread out light like a rainbow – to study exoplanets. By analyzing this data, known as spectra, researchers will be able to measure exoplanets’ compositions and chemistries. Spectra will help refine what we know about any exoplanet Webb observes, including massive gas giants, mid-sized ice giants, and smaller rocky exoplanets (some of which could be similar to Earth). In a few cases, JWST will deliver images of exoplanets to reveal more about them.

Continue Reading

The Sound of Science

Posted by admin on May 28, 2023
Posted in: First Friday Astronomy, Public Outreach. Tagged: , , , .
The roar of the Death Star exploding would have been impossible to hear at a distance since sound can’t travel in space.

Even though sound cannot propagate through the vacuum of space, that doesn’t mean we don’t know what space sounds like. Audio recordings have provided a wealth of information for space scientists almost since the beginning of the space era. Because of their simple and robust operation, microphones have been included on many past and recent space missions, on which they have recorded wind sounds and dust sounds. They will even accompany NASA’s return mission to Saturn’s moon Titan in the 2030s. Audio recordings allow us to reach far across space but also back and forth through time, and probably the last, soulful vestiges of human civilization will persist in the form of audio long after we’re gone.

Continue Reading

Unveiling Cosmic Monsters

Posted by admin on April 3, 2023
Posted in: First Friday Astronomy, Public Outreach.
HST image of the AGN at the center of Messier 87, spewing a jet of plasma, 5000 light years long. From https://en.wikipedia.org/wiki/Messier_87.

Hidden within the depths of a distant galaxy, a luminous behemoth lurks. As it greedily devours whole star systems, the leviathan unlooses a blistering spurt of flame light years long and crackling so loudly it can be heard across the Universe. Astronomers first discovered these cosmic monsters, called active galactic nuclei or AGN, during World War II. Even though they are some of the brightest objects in the Universe, clouds of dust and gas within their host galaxies obscure their machinations. Understanding the evolution of galaxies and the formation of planetary systems requires unveiling these cosmic monsters, and computer simulations coupled with JWST observations are helping unveil these cosmic monsters.

Continue Reading

Taking the Universe’s Measure

Posted by admin on March 2, 2023
Posted in: First Friday Astronomy, Public Outreach.
The Large Magellanic Cloud, a satellite galaxy of the Milky Way. From Wikipedia.

On a clear night in central Idaho, you can see the sweep of our own Milky Way galaxy split the velvet sky. Although we now know the observable Universe spans 13 billion light years, in the 1920s, astronomers didn’t even know how big the Milky Way was. In fact, many astronomers believed our galaxy comprised the entire universe and that what we now know as different galaxies were just strange nebulae within the Milky Way. The story of how astronomers finally took the true measure of the Universe as a result of the the tireless efforts of a human computer.

Continue Reading