spectroscopy Archives

September 21, 2022September 21, 2022 by Matt Williams

Webb Turns its Infrared Gaze on Mars

Graphic of Webb’s 2 NIRCam instrument images of Mars, taken on Sept. 5, 2022. Credit: NASA, ESA, CSA, STScI, Mars JWST/GTO team

The James Webb Space Telescope (JWST) is the most complex and sophisticated observatory ever deployed. Using its advanced suite of infrared instruments, coronographs, and spectrometers – contributed by NASA, the European Space Agency (ESA), and the Canadian Space Agency (CSA) – this observatory will spend the next ten to twenty years building on the achievements of its predecessor, the venerable Hubble. This includes exoplanet characterization, star and planet formation, and the formation and evolution of the earliest galaxies in the Universe.

However, one of the main objectives of the JWST is to study the planets, moons, asteroids, comets, and other celestial bodies here in the Solar System. This includes Mars, the first Solar planet to get the James Webb treatment! The images Webb took (recently released by the ESA) provide a unique perspective on Mars, showing what the planet looks like in infrared wavelengths. The data yielded by these images could provide new insight into Mars’ atmosphere and environment, complimenting decades of observations by orbiters, landers, rovers, and other telescopes.

May 16, 2022May 16, 2022 by Evan Gough

Astronomers Find a Star That Contains 65 Different Elements

This is an image of M80, an ancient globular cluster of stars. Since these stars formed in the early universe, their metallicity content is very low. This means that gas giants like Jupiter would be rare or non-existent here, while brown dwarfs are likely plentiful. Image: By NASA, The Hubble Heritage Team, STScI, AURA - Great Images in NASA Description, Public Domain, https://commons.wikimedia.org/w/index.php?curid=6449278

Have you ever held a chunk of gold in your hand? Not a little piece of jewelry, but an ounce or more? If you have, you can almost immediately understand what drives humans to want to possess it and know where it comes from.

We know that gold comes from stars. All stars are comprised primarily of hydrogen and helium. But they contain other elements, which astrophysicists refer to as a star’s metallicity. Our Sun has a high metallicity and contains 67 different elements, including about 2.5 trillion tons of gold.

Now astronomers have found a distant star that contains 65 elements, the most ever detected in another star. Gold is among them.

August 19, 2021August 16, 2021 by Paul M. Sutter

Astronomy Jargon 101: Spectrum

The spectrum from a giant exoplanet, orbiting around the bright, young, star HR 8799. Image Credit: ESO/M. Janson

In this series we are exploring the weird and wonderful world of astronomy jargon! You’ll get the whole picture with today’s topic: spectrum!

June 13, 2021June 13, 2021 by Andy Tomaswick

What’s the Connection Between the Chemistry of a Star and the Formation of its Planets?

Scientists seem to have come up with a new parlor game – how many ways can we potentially detect exoplanets? The two most common methods, the transit method and the Doppler method, each have their own problems. Alternative methods are starting to sprout up, and a new one was recently proposed by Jacob Nibauer, an undergraduate student in the University of Pennsylvania’s Department of Physics and Astronomy. His suggestion: look at a star’s chemical composition. And his findings after analyzing data on some 1,500 stars hold some surprises.

June 13, 2021June 14, 2021 by Andy Tomaswick

How To Search the Chemical Makeup of Exoplanet Atmospheres for Hints at Their History

Author’s note – this article was written with Dr. Vincent Kofman, a scientist at NASA’s Goddard Space Flight Center (GSFC), working in the Sellers Exoplanet Environments Collaboration (SEEC), and the lead author on the research it discusses.

Thousands of exoplanets have been discovered in the recent decades. Planet hunters like TESS and Kepler, as well as numerous ground-based efforts, have pushed the field and we are starting to get a total number of planets that will allow us to perform effective statistical analysis on some of them.

Not only do the detected number of planets show us how common they are; it exposes our lack of understanding about how planets form, what conditions are present, and when planets may be habitable. The transit detection of an exoplanet primarily yields the orbital period, or the length of a year on the planet, and the relative size of the planet with respect to the star. The next steps are to characterize the planet. This usually requires follow up studies, using different observational strategies and more powerful telescopes.

June 6, 2021June 14, 2021 by Matt Williams

New Technique to Search for Life, Whether or not it’s Similar to Earth Life

Artist’s impression of a sunset seen from the surface of an Earth-like exoplanet. Credit: ESO/L. Calçada

In 1960, the first survey dedicated to the Search for Extraterrestrial Intelligence (SETI) was mounted at the Green Bank Observatory in West Virginia. This was Project Ozma, which was the brainchild of famed astronomer and SETI pioneer Frank Drake (for whom the Drake Equation is named). Since then, the collective efforts to find evidence of life beyond Earth have coalesced to create a new field of study known as astrobiology.

The search for extraterrestrial life has been the subject of renewed interest thanks to the thousands of exoplanets that have been discovered in recent years. Unfortunately, our efforts are still heavily constrained by our limited frame of reference. However, a new tool developed by a team of researchers from the University of Glasgow and Arizona State University (ASU) could point the way towards life in all of its forms!

January 27, 2021January 27, 2021 by Evan Gough

Astronomers Find a Planet Like Jupiter, but It Doesn’t Have any Clouds

This artist's illustration shows the exoplanet WASP-62B. Searching for chemical biosignatures on exoplanets is a painstaking process, weighed down by assumptions and prone to false positives. Is there a better way to find exoplanets with a chance to support life? Image Credit: CfA

Can you picture Jupiter without any observable clouds or haze? It isn’t easy since Jupiter’s latitudinal cloud bands and its Great Red Spot are iconic visual features in our Solar System. Those features are caused by upswelling and descending gas, mostly ammonia. After Saturn’s rings, Jupiter’s cloud forms are probably the most recognizable feature in the Solar System.

Now astronomers with the Center for Astrophysics | Harvard & Smithsonian (CfA) have found a planet similar in mass to Jupiter, but with a cloud-free atmosphere.

October 25, 2020October 30, 2020 by Matthew Cimone

The Color of Habitable Worlds

An arrangement of 3 exoplanets to explore how the atmospheres can look different based on the chemistry present and incoming flux. - image and image description by Jack H. Madden used with permission

“This is where we live. On a Blue Dot.” said Carl Sagan when the now famous Pale Blue Dot photo was released. Captured February 14, 1990 by the Voyager 1 Space Probe, Pale Blue Dot remains the most distant photograph of the Earth ever taken at 6 billion kilometers. This past February marked the 30^th anniversary of Pale Blue Dot which was reprocessed using modern digital photo techniques creating an even more remarkable image.

This updated version of the iconic “Pale Blue Dot” image taken by the Voyager 1 spacecraft uses modern image-processing software and techniques to revisit the well-known Voyager view while attempting to respect the original data and intent of those who planned the images. Credit: NASA/JPL-Caltech

Whether Pale Blue Dot, or Blue Marble, our planet is associated with the color blue. As Earth is the only inhabited world we know of, it might stand to reason that other habitable planets in space will also be blue. But it’s a little more complicated than that.

September 17, 2020September 17, 2020 by Evan Gough

James Webb Will Look for Signs of Life on Planets Orbiting Dead Stars

A planet orbiting a small star produces strong atmospheric signals when it passes in front, or “transits,” its host star, as pictured above. White dwarfs offer astronomers a rare opportunity to characterize rocky planets. Image Credit: Jack Madden/Carl Sagan Institute

Can the galaxy’s dead stars help us in our search for life? A group of researchers from Cornell University thinks so. They say that watching exoplanets transit in front of white dwarfs can tell us a lot about those planets.

It might even reveal signs of life.

August 26, 2020August 26, 2020 by Matthew Cimone

There’s No Chemical Difference Between Stars With or Without Planets

Orion Nebula - Closest Star Forming Region to Earth c Cimone - Trottier Observatory

Strange New Worlds

Imagine if a star could tell you it had planets. That would be really helpful because finding planets orbiting distant stars – exoplanets – is hard. We found Neptune, the most distant planet in our own solar system, in 1846. But we didn’t have direct evidence of a planet around ANOTHER star until….1995.…149 years later. Think about that. Any science fiction you watched or read that was written before 1995 which depicted travel to exoplanets assumed that other planets even existed. Star Trek: The Next Generation aired its last season in 1994. We didn’t even know if Vulcan was out there. (Now we do!…sortof)