The first confirmation of a planet orbiting a star outside our solar system happened in 1995. We now know that these worlds – also known as exoplanets – are abundant. So far, we’ve confirmed more than 4000. Even though these planets are far, far away, we can still study them using ground-based and space-based telescopes.
Our upcoming James Webb Space Telescope will study the atmospheres of the worlds in our solar system and those of exoplanets far beyond. Could any of these places support life? What Webb finds out about the chemical elements in these exoplanet atmospheres might help us learn the answer.
How do we know what’s in the atmosphere of an exoplanet?
Most known exoplanets have been discovered because they partially block the light of their suns. This celestial photo-bombing is called a transit.
During a transit, some of the star’s light travels through the planet’s atmosphere and gets absorbed.
The light that survives carries information about the planet across light-years of space, where it reaches our telescopes.
(However, the planet is VERY small relative to the star, and VERY far away, so it is still very difficult to detect, which is why we need a BIG telescope to be sure to capture this tiny bit of light.)
So how do we use a telescope to read light?
Stars emit light at many wavelengths. Like a prism making a rainbow, we can separate light into its separate wavelengths. This is called a spectrum. Learn more about how telescopes break down light here.
Visible light appears to our eyes as the colors of the rainbow, but beyond visible light there are many wavelengths we cannot see.
Now back to the transiting planet…
As light is traveling through the planet’s atmosphere, some wavelengths get absorbed.
Which wavelengths get absorbed depends on which molecules are in the planet’s atmosphere. For example, carbon monoxide molecules will capture different wavelengths than water vapor molecules.
So, when we look at that planet in front of the star, some of the wavelengths of the starlight will be missing, depending on which molecules are in the atmosphere of the planet.
Learning about the atmospheres of other worlds is how we identify those that could potentially support life…
…bringing us another step closer to answering one of humanity’s oldest questions: Are we alone?
Watch the full video where this method of hunting for distant planets is explained:
To learn more about NASA’s James Webb Space Telescope, visit the website, or follow the mission on Facebook, Twitter and Instagram.
Text and graphics credit Space Telescope Science Institute
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[id: Tweet by Dinah Applewhite @Dinahlew · Aug 6 reading “Tax dollars at work. Crushing wheelchairs” A photo is attached of a garbage truck crushing wheelchairs. It is dark out. Second image: Tweet again by @Dinahlew reading: “For context: this was part of ‘Operation Clean Sweep’ in Boston. I watched as peoples’ belongings-including wheelchairs-were thrown into a dumptruck. People were crying. There were many cops present helping to coordinate this. I couldn’t believe what I was seeing. The cruelty.” end id]
In addition to the rampant dehumanization of homeless people & people with substance use disorders, there’s a clear influence of ableism in the police’s response to this: in the article, Boston police spokesperson John Boyle says “Nobody was taken out a wheelchair and the wheelchair was thrown away. It wasn’t a case of that. It was abandoned property.” while the wheelchair user himself & his partner say he only left his chair for a minute and is unable to be mobile without it.
Stereotypes that all wheelchair users must be totally nonambulatory support this destruction of property; ‘obviously,’ people think, ‘if they really needed a wheelchair, they’d be in it right now, so it must be abandoned,’ and although the people who destroyed these chairs know that’s bullshit because someone was actively pleading with them not to take it, there’s a strong chance that the general public will buy that excuse.
This is one of the many, many reasons disabled people without substance use disorders absolutely have to be in solidarity with people with substance use disorders & movements promoting their health and safety. I’ve seen too many people with chronic pain blame doctors denying us pain medications on people with substance use disorders—this is not an “us versus them” issue, and constantly repeating ‘i’m not an addict, i’m one of the good, responsible users’ is just hurting other vulnerable people.
This blog is mostly so I can vent my feelings and share my interests. Other than that, I am nothing special.
If you don't like Left Wing political thought and philosophy, all things related to horror, the supernatural, the grotesque, guns or the strange, then get the fuck out. I just warned you.
