Q&A 148: How Do We Know the Age of the Universe? And More...

In this week's episode, I talk about the various ways we measure the age of the Universe. What's next for OSIRIS-REx? And what are the next frontiers for gravitational wave astronomy?

00:00 Start
00:41 How do we calculate the age of the Universe?
04:32 Will the planets migrate again?
06:36 What's next for OSIRIX-REx?
07:47 What's next for gravitational wave astronomy?
11:27 Does the habitable zone shift as the Sun heats up?
12:59 Will future civilizations know about the Big Bang?
18:17 Could a powerful telescope look beyond the CMB?
20:27 Could a computer become a planet-sized mind?
24:08 Is the CMB shifting away from us?
25:28 Bounties to remove space junk?
30:58 Could rockets be launched from Canada?

Want to be part of the questions show? Ask a short question on any video on my channel. I gather a bunch up each week and answer them here.

🚀 OUR WEBSITE:
════════════════════════════════════

🚀 PODCAST LINKS:
════════════════════════════════════

🚀 EMAIL NEWSLETTER:
════════════════════════════════════
Read by 50,000 people every Friday. Written by Fraser. No ads.

🚀 OTHER PODCASTS:
════════════════════════════════════
Weekly Space Hangout: Weekly news roundup with Fraser, special guests, and other space journalists.

Astronomy Cast: Award-winning, long-running deep dive into space and astronomy with Fraser and Dr. Pamela Gay.

🚀 JOIN OUR COMMUNITY:
════════════════════════════════════

🚀 OTHER SOCIAL MEDIA:
════════════════════════════════════

🚀 CONTACT FRASER:
════════════════════════════════════

🚀 LICENSE:
════════════════════════════════════
Creative Commons Attribution 4.0 International (CC BY 4.0)

You are free to use my work for any purpose you like, just mention me as the source and link back to this video.

[shmstne]

Thanks for answering my question, Fraser!

[MikeHan]

Hey Fraser! I got a question that popped into my brain after whatching your latest Q&A video. After the big bang the universe was extremely hot and as it was expanding it started to slowly cool down. So, at one point the universe must had a temperature, in which water on planets that wouldn't even need to have a star, would be in a liquid form, cause the habitable zone would basically be anywhere in the universe, as you said. Could theoretically, have such planets ever existed back then and even with life thriving on them? If so, how much time would life have to evolve on such a planet, before the temperature of the universe got too cold?

[harrypitt]

Great show. First time seeing it today. I especially enjoyed your thoughtful answers to questions. One question rattling around in my head since high school is whether there might be a pattern or force which determines the direction spiral galaxies spin, similar to how the Coriolis Effect affects air and ocean movement patterns on earth.

[ItzAllMine]

yasss. I got a question answered. thanks man

[keepeetron]

For something that starts and never ends, any time is 'close to the beginning'. What you said around 17:20 could be said even if it was trillions of years from now

[johnholleran]

Great video, as always! Question: why does it take a few weeks to upload the Q&A videos? I always get confused on whether I've seen the show live or not haha

[andrepattenden]

Oo! Oo! I’ve another question.. How could the universe ever be considered infinite if we are pretty certain that the universe had a particular size at different stages of its life? Ie. Inflation period = grapefruit, CMB at 380000yrs = 1.4m lightyears. I appreciate it’s hard to be sure what lies beyond the visible universe now and that there is much more out there than we can see or detect, but how can we ever think of the universe as infinite when at some point we’d have to transition from finite to infinite? Especially if the lifespan of the universe is fairly certainly a finite age?....

[andrepattenden]

Hi Fraser. Quick thought.. you mentioned recently that the CBR is essentially opaque because it represents the period of the universe where it was essentially a ‘solid’ mass of exotic plasma like the surface of a star (forgive me if I’m misremembering..) before the universe expanded out into more understandable matter.
Is there a calculation of how big the universe was at this stage? ...The simplistic part of my brain imagines this version of the universe as a monster ‘star’ billions of lightyears across, so do feel free to correct me if that’s way off the Mark! 😉

[ocoro]

god bless boyo pretty good questions this week

[ElwoodAndersonNV]

It is my understanding that astronomers most recently determined the age of the universe from data acquired by the WMAP satellite measurements of temperature fluctuations in the cosmic microwave background (CMB). The CMB is what we could see at the time the satellite made the measurements, so the 13.7 billion years is based on what we could see then. Isn't it possible that other remnants of the big bang lie beyond what we could see at the time, or what we may never see due to the acceleration of the expanding universe. These invisible remnants that lie beyond this horizon could have created other galaxies and stars whose mass could be drawing the mass we see within the horizon, outward, giving the appearance of a dark energy inside the horizon. Would someone comment on why this can or can't be an explanation of dark energy.

[Mosern]

Hi Fraser - why isn't the milky way present in the CMB image? Wouldn't it block measurements of the CMB in the direction of the galactic plane?

[jonasjansson]

Hello great show as always!

So I got a question all the way from Nordics, I have heard alot about how to slow down time by gravition and traveling really fast but not the other side of that spectrum. Beeing way out of any gravitation wells and *standing still (not accelerating?, don't really know what reference point to use here). Question is how much faster in time could I go if I minimize those two factors?

(Sorry messy spelling, auto-correct is set for swedish)

[josephpowell]

hey Frasier,

are we able to watch the cmb cool down over a few years or even in real time ?

i know it must be a epicly slow cooldown at 3kelvin, but those cmb maps was crazy precise and the cmb is the most perfect black body radiator.

[aelolul]

❓ What are your thoughts on the cosmological "axis of evil"? Has there been any new insights into that mystery?

[headbanga]

Two questions for the price of one :)
In there any correlation between light intensity and number of photons within a specific volume? (More photons = more intense light)
As photons and other particles (or electromagnetic waves) travel in all directions, could they interfere if they collide? Or collision are so rare that these effects are insignificant?

[deeliciousplum]

Are there any guarantees in life? Yes. Well, at least one: a Fraser Cain upload will be awesome! 🌸

[Daniel-xeym]

Hi Fraser. Adding propulsion, could the ISS be repurpose for a Mars trip?

[joecanales]

So the pattern of the CMB is changing. Are we looking for an indication (or message) of a previous aeon in the pattern

[carlfollmer]

I'm having trouble wrapping my brain around gravitational wave observatories that can't actually "see" anything. Can LIGO and VIRGO figure out what part of space the waves they detect came from (and thus how long ago they occurred) or only that gravitational events occur?

[microschandran]

Hi Fraser, is big bang gravitational waves ever detectable if we measure it in space not ground?