Hacker News new | past | comments | ask | show | jobs | submit | _marlowe_'s comments login

Can someone explain to me in minimally technical terms how scientists can determine the molecular composition of an exoplanet's atmosphere? It boggles my simple mind.


When a planet with an atmosphere eclipses its star, light passes through its atmosphere and the molecules in the atmosphere will absorb specific frequencies of light.

See https://exoplanets.nasa.gov/discovery/how-we-find-and-charac...


I would guess spectral analysis of the light coming from the planet's star. Look at the spectrum when the planet is behind the start, look at the spectrum when the planet is in front of the star (in which case part of the light passes through the planet's atmosphere). The difference between the two indicates which frequencies are absorbed by the planet's atmosphere, from which its composition can be determined. Don't take my word for it though, I'm not an astrophysicist.

In any case it boggles my mind that we can do things like that for planets thousands of light-years away from us.


They use a technique where they do spectral analysis on the light reflected from the planet. Gasses absorb different wavelengths of light. So the light reflected will have holes at specific wavelengths, and scientists can determine which combination of gasses will result in those specific absorption lines.


I thought it was just light? Light bounces off of different molecules differently?


Kinda, it's not that it bounces, it's that it passes through and is filtered by it.

For example, passing light through a hydrogen gas cloud will remove some red/IR wavelengths from the end result.

We can measure those missing wavelengths and figure out what gasses it's passed through


Fantastic stuff!


2-10 spread went through the pre-GFC record of -28 bps a day or two ago.


I'm a little sanguine about the inverted yield curve as a real signal this time around, to be honest.

We're in an environment of very rapidly rising short-term interest rates, specifically as the Fed attempts to try to manage inflation; with back-to-back 75 bps increases. That tends to have a curve flattening effect as the yield curve is nominal; short term yields rise more than longer tenors if the market believes that inflation will decrease as real yields will be higher.


GFC = Global Financial Crisis (2007-08)


You can thank the Fed. Pensions and their consultants publish an assumed rate of return, which is increasingly difficult to obtain in a sustained low interest rate environment. They have been increasing exposure to private markets to compensate for low returns in fixed income("yield seeking"). There is additional pressure since public and private pensions are typically underfunded, and overly aggressive return assumptions give cover to the states and companies that don't fund them to the extent they should.


Lived in TW2002 on Atlantis BBS for the better part of 2 years. Good times.


It would be more interesting to see this indexed against each country's respective population


I'm sorry you're having a hard time with this. My life is your counter factual, maybe it will provide a different perspective.

I was identified as highly gifted around that age as well, but my parents prevented me from participating in my schools' GATE programs. It is not hard to see how that decision cascaded through my life and led to a lot of avoidable painful outcomes.

I was so far ahead of my peers that school was unbearably tedious by grade 7 and I became a "bad kid". I did the bare minimum in high school so I could pursue my interests away from class. My GPA reflected that level of engagement.

Because my academic record screamed "truant, not motivated, difficult", I was locked out of top quality universities and scholarships I should have easily obtained. I graduated from a mediocre college with avoidable student debt and access to lower quality career options than I would have had through a better school.

I course corrected in my 30s and have had a nice career and family life, but there were 10-12 years of missed opportunities and unnecessary suffering.

Access to opportunity is like compound interest in that early success leads to more opportunity. Invest early and your life will more likely have positive social and economic outcomes. Missing opportunities early can be very costly.

I don't know if gifted kids are being pushed too hard or not. Sometimes, in an effort to provide early opportunities, parents lose sight of what it means to be a kid. That is sad, no question, but challenging gifted kids is important, because not doing so can lead to avoidable personal and professional difficulties. My life is proof of that.


I worked at GS but not in investment banking. I had a really positive experience and rarely went over 60-70 hours.

It all depends on your role. IBD is definitely the most demanding, but they all made a choice, with basically perfect information, to accept that job. I promise you, they knew it would be like that. It's hard for me to feel too sympathetic.


An orderly secondary market could increase 409a valuations and result in a higher exercise price for stock options.

Seems like senior execs don't have much incentive to accommodate that...


Jonathan Tepper wrote a great book about this, the Myth of Capitalism


Join us for AI Startup School this June 16-17 in San Francisco!

Guidelines | FAQ | Lists | API | Security | Legal | Apply to YC | Contact

Search: