The Oldest Galaxies in the Universe
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The Oldest Galaxies in the Universe
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Re: The Oldest Galaxies in the Universe
#2Although the Webb telephone will be 100x better than Hubble, you gotta wonder if it wouldn't be useful to keep Hubble around for a few more decades. Surely, there's enough work for both.
Re: The Oldest Galaxies in the Universe
#3Although the Webb telephone will be 100x better than Hubble, you gotta wonder if it wouldn't be useful to keep Hubble around for a few more decades. Surely, there's enough work for both.
Absolutely, Hubble can see in the optical and near-UV, while James Webb will be limited to the infrared. "Limited" is one way of putting it, it'll be immensely valuable in finding astrophysical phenomena and also distant Solar System objects (Perhaps yet bigger Pluto's orbiting in the distance).
We also need specialized spacecraft in the vein of Terrestrial Planetary Finder and definitely a follow-on mission of Kepler, as well as ground-based planet-finding telescopes like Colossus: http://the-colossus.com/ .
We could also use a systematic search for solar systems similar to [KIC 8462852](https://en.wikipedia.org/wiki/KIC_8462852).
Re: The Oldest Galaxies in the Universe
#4This is a spurious comment but how neat to be blasted by photons which have travelled for billions of years.
I presume, if they're hitting the telescope they're probably hitting me (which does make me feel a little self centered).
I wonder how long they will keep traveling?
The cosmos have been super interesting lately with those weird formations orbiting one star and the SETI project being refocused on another after detecting a strange sequence of lights. (I am barely a lay man here so bear with me if I'm making an ass of myself astronomers). And of course the Mars rover and those beautiful shots of Pluto.
I look forward to a tremendous amount more. I've got a book on Einstein's Theory of Relativity, and a beautiful illustrated copy of Stephen Hawking's most famous work (I cannot seem to remember the title). After Catch-22 I believe I'll check them out.
If anyone has any other suggestions for understanding the cosmos I'd be indebted.
Re: The Oldest Galaxies in the Universe
#5Every atom in your body was forged in a star. The iron in your blood, the oxygen and carbon that make up the proteins and fats that allow complex organisms to exist, the copper and gold we use for wiring, the uranium we're splitting for energy; all of it was made by a star that had used up all its hydrogen and started fusing heavier elements.
Nearly all of the energy we use on earth (a small fraction is from nuclear decay) is stored sunlight. The gasoline we burn? That was sunlight that got converted into a plant, which was converted into a growing dinosaur that ate plants, which died and was converted into oil over billions of years of heat and pressure.
Thinking of that always makes me smile at how somewhat accidentally right ancient people who worshiped the sun as a god were.
Re: The Oldest Galaxies in the Universe
#6This is a spurious comment but how neat to be blasted by photons which have travelled for billions of years. I presume, if they're hitting the telescope they're probably hitting me (which does make me feel a little self centered). I wonder how long they will keep traveling? The cosmos have been super interesting lately with those weird formations orbiting one star and the SETI project being refocused on another after…
A Brief History of Time is the book by Stephen Hawking. It's really approachable and easy to read. I also liked The Elegant Universe by Brian Greene. That was the first book I read where the author was able to explain both the standard model of physics and special and general relativity in ways that made sense to me.
Re: The Oldest Galaxies in the Universe
#7Every atom in your body was forged in a star. The iron in your blood, the oxygen and carbon that make up the proteins and fats that allow complex organisms to exist, the copper and gold we use for wiring, the uranium we're splitting for energy; all of it was made by a star that had used up all its hydrogen and started fusing heavier elements. Nearly all of the energy we use on earth (a small fraction is from nuclear…
Indeed, and in fact there's an additional interesting twist: Stellar fusion can only produce elements up to the atomic weight of iron. Production of heavier elements requires a supernova. So we know that our solar system is at least one stellar life cycle removed from the earliest stars.
Re: The Oldest Galaxies in the Universe
#8This is a spurious comment but how neat to be blasted by photons which have travelled for billions of years. I presume, if they're hitting the telescope they're probably hitting me (which does make me feel a little self centered). I wonder how long they will keep traveling? The cosmos have been super interesting lately with those weird formations orbiting one star and the SETI project being refocused on another after…
A Brief History of Time is the book by Stephen Hawking. It's really approachable and easy to read. I also liked The Elegant Universe by Brian Greene. That was the first book I read where the author was able to explain both the standard model of physics and special and general relativity in ways that made sense to me.
Agreed about both books. The Elegant Universe explains clearly how Relativity and Quantum Mechanics conflict, and how String Theory solves that problem. I should reread the Hawking book, I haven't read it since college.
Re: The Oldest Galaxies in the Universe
#9This is a spurious comment but how neat to be blasted by photons which have travelled for billions of years. I presume, if they're hitting the telescope they're probably hitting me (which does make me feel a little self centered). I wonder how long they will keep traveling? The cosmos have been super interesting lately with those weird formations orbiting one star and the SETI project being refocused on another after…
How do they know the photons were from billions of years ago?
Re: The Oldest Galaxies in the Universe
#10This is a spurious comment but how neat to be blasted by photons which have travelled for billions of years. I presume, if they're hitting the telescope they're probably hitting me (which does make me feel a little self centered). I wonder how long they will keep traveling? The cosmos have been super interesting lately with those weird formations orbiting one star and the SETI project being refocused on another after…
How do they know the photons were from billions of years ago?
If an object is measured to be a billion light years away, that means that light from that object takes a billion years to get here.