21–30 of 252 posts
I guess the “as seen from our current vantage point” is understood, but to me the needless emphasis of that perspective just muddies things, no?
Anyone of you downvoters care to enlighten me?
I've always been puzzled by the estimated age of the universe at being 13 billion years. That's just the size of the observable universe, correct? Isn't there a future horizon beyond which light will not currently reach us?
Nice gravitational lens observation! We're hoping to use the same technique with the Sun to observe exoplanets by launching a fleet of small satellites to 547 AU (80 billion km / ~3 light days). The craft would sample the distorted Einstein ring around our Sun from that vantage point, then combine and reconstruct an image of the disk of an Earth-like exoplanet up to 100 light-years beyond, at a resolution of 25 kilom…
> it’d still take 25 to 30 years for them to reach a vantage point .... > mission designers would have to pick carefully because they could observe only a single target It will take 30 years to get in position but then we can only look at one target? While it sounds very neat, I'd rather fund something we can use more than once, and sooner.
Starship is going to open so many opportunities.
I find it funny when scientific articles (esp. pop astronomy) describe something as weird, bizarre, or extremely unlikely. We're reversing the effects of gravitational lensing on a galaxy at a distance that's a significant fraction of the radius of the observable universe. Are astronomers that confident in their models that the inferred shape of this galaxy is bizarre? I'd love to have that level confidence in softwa…
>Clearly, the theoretical models are wrong, or at least (and more likely) incomplete. Obviously, there’s more to learn about galaxies that exist at the edge of the observable Universe.
I am reminded of that tale about how "Eureka!" is not exclamation of good science but instead "That's odd.". This article is saying "That's odd." in a way that signals we are on the verge of new scientific discovery.
(I can't help but wonder what Douglas Adams would make of this sort of thing - or the present time, for that matter.)
Nice gravitational lens observation! We're hoping to use the same technique with the Sun to observe exoplanets by launching a fleet of small satellites to 547 AU (80 billion km / ~3 light days). The craft would sample the distorted Einstein ring around our Sun from that vantage point, then combine and reconstruct an image of the disk of an Earth-like exoplanet up to 100 light-years beyond, at a resolution of 25 kilom…
First thought is that it can be a small blob galaxy in front of a bigger one.
I've always been puzzled by the estimated age of the universe at being 13 billion years. That's just the size of the observable universe, correct? Isn't there a future horizon beyond which light will not currently reach us?
No, 13 billion years is the age of the universe. The observable universe is a sphere with a diameter of ~93 billion light years (And is likely to only be a subset of the entire universe).
I've always been puzzled by the estimated age of the universe at being 13 billion years. That's just the size of the observable universe, correct? Isn't there a future horizon beyond which light will not currently reach us?
No, 13 billion years is the age of the universe. The observable universe is a sphere with a diameter of ~93 billion light years (And is likely to only be a subset of the entire universe).
https://starchild.gsfc.nasa.gov/docs/StarChild/questions/que....
Earlier quoted context omitted.
No, 13 billion years is the age of the universe. The observable universe is a sphere with a diameter of ~93 billion light years (And is likely to only be a subset of the entire universe).
How can we observe things over 40 billion light years away if they've only been around to emit light for 13 billion years?