Althouse: The "oldest dust" is "in a galaxy with only a number for a name in a constellation called Sculptor, and so far away that its distance barely has any meaning."

March 8, 2017

The "oldest dust" is "in a galaxy with only a number for a name in a constellation called Sculptor, and so far away that its distance barely has any meaning."

"The light from A2744_YD4, as it is known, has been on its way to us for 13.2 billion years, since the universe was only 600 million years old."

52 comments:

Original Mike said...: The Milky Way has dust just as old, though most of the dust in the M.W. is younger.

BTW, virtually all galaxies we can observe have not been given a name, just a catalog number.; 3/8/17, 9:07 AM
Owen said...: "Oldest dust" is charged with poetic possibility. But what does it mean to say that a distance is so great as almost to lose its meaning? Is there a scale of meaningfulness, so that light coming from "only" 10 billion LY or coming from "right next door" at 1 billion LY is more important or affects us in a different and "bigger" way?

We are fascinated with origin stories, particularly ones that must remain impenetrable. Nothing can be older than the Big Bang, because Time requires Matter in Space, the makings of the clock that can then tick out the moments from there to here, all 13-odd billion years of them. Given that fascination, why would we not consider this earliest light to be more, not less, meaningful?; 3/8/17, 9:09 AM
Bob Boyd said...: 13.8 billion years.
A day without a woman.; 3/8/17, 9:13 AM
Wince said...: Did you know that across the span of time since the 1974, the Ford Galaxie has become the Ford Galaxy, a mini-van?; 3/8/17, 9:20 AM
Todd said...: Is it a "tell" that they use the term "polluted" in “More observations should pinpoint the period when galaxies began to be first polluted by heavy elements,” Dr. Ellis said in an email from London.?

Is that our fault too, that the galaxies started to get polluted? Will the Sierra Club use this in tomorrow's fund raiser?; 3/8/17, 9:20 AM
Original Mike said...: Aslo several nice, big, close galaxies in Sculptor.; 3/8/17, 9:21 AM
Original Mike said...: @Todd: "Polluted" is a term that's been used in the astronomy literature for decades to describe the process of the accumulation of heavier elements in the primordial soup. It's just an attempt to be poetic.; 3/8/17, 9:24 AM
rhhardin said...: Oldest dust dates from 1975 in my house.; 3/8/17, 9:28 AM
traditionalguy said...: Oh boy. Let's send a NASA manned mission to Sculpter. It is as smart as sending men to Mars, in other words it will spend mega-loot on Crony Contracts.; 3/8/17, 9:28 AM
Ignorance is Bliss said...: The light from A2744_YD4, as it is known, has been on its way to us for 13.2 billion years, since the universe was only 600 million years old.

The light has been traveling for 13.2 billion years, yet hasn't aged a day. Since it is traveling at the speed of light, it does not experience time.; 3/8/17, 9:29 AM
Todd said...: Original Mike said...
@Todd: "Polluted" is a term that's been used in the astronomy literature for decades to describe the process of the accumulation of heavier elements in the primordial soup. It's just an attempt to be poetic.

3/8/17, 9:24 AM

Interesting... I do a reasonable amount of reading on astronomy and don't believe I have encountered the use of that word before but I will acquiesce to your position.

I suppose it is similar to the use of the term "doping" in IC design and development...; 3/8/17, 9:32 AM
rhhardin said...: 13.2 billion years BC.; 3/8/17, 9:33 AM
CWJ said...: IiB,

True, neither has the dust. Our view of the "oldest dust" is when it was very young dust. Who knows what it looks like now (whatever "now" means).; 3/8/17, 9:38 AM
dbp said...: Althouse checks-out the stars in Death Valley and then notices an article on astronomy and how our universe is inconceivably old and vast.

Did she seek out articles on astronomy because, let's face it, the sky on a dark night is pretty compelling? Or because it just happened to be in the NYT? I vote for the latter and further proof that we are living in a computer simulation.; 3/8/17, 9:38 AM
rhhardin said...: We know the universe isn't infinitely old because if it were it couldn't be now yet.; 3/8/17, 9:42 AM
Anonymous said...: Blogger rhhardin said...
Oldest dust dates from 1975 in my house.

3/8/17, 9:28 AM
------------------------------------

Yes. It lays in layers like tree rings.
This weeks cleaning will get me back to the 1999 layer,; 3/8/17, 9:47 AM
Fernandinande said...: a galaxy with only a number for a name

I dub thee "Quigley".; 3/8/17, 10:08 AM
madAsHell said...: Old dust? How do you measure time in very remote dust? Does it correlate to REALLY big dust bunnies?; 3/8/17, 10:17 AM
Owen said...: Lars Porsena: take good notes as you go down/back into the record. Climate science relies on proxy thermometers, and your dust bunnies may become the new metric.; 3/8/17, 10:18 AM
Levi Starks said...: Or maybe the light was here all along, but the Galaxy/dust has simply been moving away from us for 13 billion years.; 3/8/17, 10:19 AM
eric said...: If we make really big numbers the crap we spew is harder to refute.; 3/8/17, 10:21 AM
Original Mike said...: This comment has been removed by the author.; 3/8/17, 10:25 AM
Original Mike said...: "Or maybe the light was here all along, but the Galaxy/dust has simply been moving away from us for 13 billion years."

Well, in a very real sense that's exactly what's been happening. Expansion of the universe.

As quoted in the article, the galaxy from which the light was emitted 13 billion years ago is now 30 billion light-years away.; 3/8/17, 10:29 AM
Original Mike said...: "If we make really big numbers the crap we spew is harder to refute."

You don't believe the universe is big?; 3/8/17, 10:30 AM
traditionalguy said...: Adam's hardest job besides knocking up Eve and ruling the earth was naming the Animals...and now we have to name Trillions of stars. This being a Man is hard work.; 3/8/17, 10:33 AM
Gospace said...: One of the problems with times and the universe having a starting point. At 600 million years, the universe could only be 600 million light years across. How is it that light, that travels at the speed of one light year per year, took 13.2 billion years to cover 600 million light years of travel?; 3/8/17, 10:36 AM
Original Mike said...: "At 600 million years, the universe could only be 600 million light years across."

It was bigger than that. Space can (and does) expand faster than the speed of light.; 3/8/17, 10:38 AM
Owen said...: Since we are talking about stars on This Day Without Womyn, let me honor the fair sex by mentioning a fun book by Dava Sobel (author of "Longitude") which tells the story of the women "computers" and astronomers at Harvard and elsewhere in the 1880's through to the 1950's who did amazing work to catalog, identify and decipher the stars. "The Glass Universe."; 3/8/17, 10:50 AM
n.n said...: Inference drawn from assumptions/assertions about the characterization of "Space" as space. The "Big Bang" theory was not the beginning, but realized significant progress in post-normal science, notably "secular" theories of physical and human creation (e.g. spontaneous conception).; 3/8/17, 11:05 AM
Fernandinande said...: Original Mike said...
Space can (and does) expand faster than the speed of light.

"Astrophysicist at The Ohio State University" says "Distance moved divided by time equals speed, and I guarantee you that the speed you measure can be faster than light."

Ask a Mathematician/Physicist says: "You’ll often hear that 'the universe is expanding faster than the speed of light'. However, this statement is akin to statements like 'green is bigger than happy'. It’s not even wrong."

Physicist at Cal-Tech says: "The Universe Never Expands Faster Than the Speed of Light"

This concludes our Appeal to Authority.; 3/8/17, 11:14 AM
Fernandinande said...: http://www.askamathematician.com/2014/03/q-how-can-the-universe-expand-faster-than-the-speed-of-light/; 3/8/17, 11:14 AM
Original Mike said...: @Fernandinande: The observable universe is currently 46 billion light-years in width yet it has been expanding for only 14 billion years. You are free to descibe that any way you choose.; 3/8/17, 12:21 PM
Drago said...: Fernandinande: "This concludes our Appeal to Authority."

Ponders comment, presses button: "Bring me more Authorities!"; 3/8/17, 12:27 PM
Original Mike said...: My bad. Objects at the edge of observability (basically the CMB radiation) is 46 billion light years so the width of the observable universe is twice that; 92 billion light years.; 3/8/17, 1:26 PM
Yancey Ward said...: Well, I no longer feel guilty about not dusting the blinds for a year.; 3/8/17, 2:44 PM
Yancey Ward said...: Well, if we can explain why space can expand faster than the speed of light, there is hope for explaining a subzero IQ. I am searching for a unified theory to explain our progressive trolls.; 3/8/17, 2:48 PM
Drago said...: Yancey Ward: "Well, I no longer feel guilty about not dusting the blinds for a year"

I think you meant "light-year".; 3/8/17, 3:35 PM
'TreHammer said...: So you run and you run to catch up with the sun but it's sinking
Racing around to come up behind you again.
The sun is the same in a relative way but you're older,
Shorter of breath and one day closer to death.

...true, that...with apologies to Pink Floyd...; 3/8/17, 3:50 PM
Jason said...: Einstein at the station: "Does Vienna stop at this train?"; 3/8/17, 4:35 PM
The Godfather said...: OK Original Mike, let me try to understand this. "Objects at the edge of observability (basically the CMB radiation) is 46 billion light years" away from us. But because the universe is only around (say) 14 billion years old, what we see at the edge of observability is light that cannot be older than 14 billion years, and hence the source of that light couldn't have been further from us than 14 billion light years at the time it was generated. So how can we "observe" light that comes from 46 billion light years away? Is it possible to explain this without resorting to really complicated math? I'm just a lawyer.; 3/8/17, 4:39 PM
Original Mike said...: Blogger Jason said..."Einstein at the station: "Does Vienna stop at this train?""

I like it.; 3/8/17, 5:12 PM
Original Mike said...: Godfather: Let's imagine that back 14 billion years ago an object emits a light photon that is destined to enter our eye tonight. However, because of the expansion of space the object that emitted the photon has been receding from us for those 14 billion years so that today it is 46 billion light-years away.; 3/8/17, 5:25 PM
Levi Starks said...: But using that logic, wouldn't light be traveling at faster than the speed of light?; 3/8/17, 5:57 PM
Original Mike said...: Levi, it may by the difference between special and general relativity. "The speed of light as a constant" is a special relativity tenant. Space is static in special relativity. Just guessing.; 3/8/17, 6:24 PM
Paul Snively said...: Todd: I suppose it is similar to the use of the term "doping" in IC design and development...

Exactly, and for the same reason: astronomical "pollution" by heavy elements refers to the heavy elements being things for photons to collide with—photons that collide with heavy elements before reaching the telescope, er, don't reach the telescope. Which makes being an astronomer significantly more challenging than it already is.

re: the 14B vs. 46B light-years, Original Mike has it exactly right: it's explained by the expansion of the universe following the Big Bang, and one of the primary insights, if not the primary insight, of Einstein's in his general theory vs. his special theory is that the topology of spacetime is not fixed. (This is also a major headache for getting quantum mechanics and relativity to line up: there are theories of quantum mechanics consistent with special relativity and its fixed spacetime background, but theories consistent with general relativity remain elusive, to put it mildly).; 3/8/17, 6:37 PM
Bad Lieutenant said...: "The "oldest dust" is "in a galaxy with only a number for a name..."

It's the galaxy next to Arch Stanton. So start dusting, Tuco.; 3/8/17, 7:07 PM
Michael McNeil said...: It's hard to say how old the oldest star — much less stars with planets — in the Galaxy might be. However, a “mere” 117 light years away from the Sol system lies the star and its system dubbed Kepler-444, around which orbit five terrestrial (rocky) planets between Mercury and Venus (Earth) in size (whose orbits unfortunately all lie well within the so-called “habitable zone”), but whose age (determined by a relatively new technique known as “asteroseismology” involving stellar oscillations which can reveal some stars' age) has been found to be an astounding 11.2 billion years — or some 80% of the 13.8 billion year age of the universe. The solar system's age, by contrast, at 4.6 billion years old is only 1/3 (33%) of the age of the universe.; 3/8/17, 7:08 PM
Ambrose said...: An intelligent creator could have made a universe at any point in time in which there were light emitting bodies with beams of photons any number of light years from them.; 3/8/17, 10:26 PM
Michael Fitzgerald said...: Bad Lieutenant said...
"The "oldest dust" is "in a galaxy with only a number for a name..."

It's the galaxy next to Arch Stanton. So start dusting, Tuco.

3/8/17, 7:07 PM

Blondie, you're a son of a -!; 3/9/17, 12:40 AM
Yancey Ward said...: You see, in this world there's two kinds of people, my friend- those with loaded guns ... and those who dust.; 3/9/17, 1:33 AM
Bad Lieutenant said...: "But the pity is that when I'm paid, I always follow my job through. You know that, Andromeda."

"NO! MILKY WAY!!!"; 3/9/17, 7:06 AM
Bad Lieutenant said...: Michael Fitzgerald said...
Bad Lieutenant said...
"The "oldest dust" is "in a galaxy with only a number for a name..."

It's the galaxy next to Arch Stanton. So start dusting, Tuco.

3/8/17, 7:07 PM

Blondie, you're a son of a -!

3/9/17, 12:40 AM

Just a dusty son of a-Aaaaah! Yes, I know who I am.; 3/9/17, 8:46 PM