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Billion Star Surveyor 'Gaia' Lifts Off

samzenpus posted about 10 months ago | from the its-full-of-stars dept.

Space 77

mrspoonsi writes "BBC Reports: 'Europe has launched the Gaia satellite — one of the most ambitious space missions in history. The 740m-euro (£620m) observatory lifted off from the Sinnamary complex in French Guiana at 06:12 local time (09:12 GMT). Gaia is going to map the precise positions and distances to more than a billion stars. This should give us the first realistic picture of how our Milky Way galaxy is constructed. Gaia's remarkable sensitivity will lead also to the detection of many thousands of previously unseen objects, including new planets and asteroids. Gaia will use this ultra-stable and supersensitive optical equipment to pinpoint its sample of stars with extraordinary confidence. By repeatedly viewing its targets over five years, it should get to know the brightest stars' coordinates down to an error of just seven micro-arcseconds. "This angle is equivalent to the size of a euro coin on the Moon as seen from Earth," explained Prof Alvaro Gimenez, Esa's director of science.'"

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Total map size (4, Interesting)

mrspoonsi (2955715) | about 10 months ago | (#45744039)

The article states it will map 1% of our Milky Way, and there are 170 billion Galaxies in the universe, so that is: 0.0000000000005% mapping of the known universe (if my figures are correct).

Re:Total map size (2)

StoneCrusher (717949) | about 10 months ago | (#45744085)

Don't forget that every time we try to count them, there turns out to be more than expected.

While this telescope is focused on high accuracy of closer stars, so it may not be finding any more galaxies, I wouldn't be surprised if it finds even more stars in the Milky Way than we previously estimated. This seems to happen every time we take a closer look.

From the article

it is likely also to see a colossal number of objects that have hitherto gone unrecorded - such as comets, asteroids, planets beyond our Solar System, cold dead stars, and even tepid stars that never quite fired into life.

It seems even the definition of star isn't always clear.

Re:Total map size (3, Insightful)

FlyHelicopters (1540845) | about 10 months ago | (#45744539)

What you say is very true...

Anyone who doubts this should go to YouTube and search for "Hubble Ultra Deep Field".

Amazing video...

Hope Nasa can help us on that (0)

Taco Cowboy (5327) | about 10 months ago | (#45744675)

It seems even the definition of star isn't always clear

I fervently hope that Nasa will get enough fund to construct a much powerful equipment than Gaia and sent it to space to help us understand the universe better.

I fervently hope that the American government will stop wasting money on all the wasteful and counter-productive pork-barrel programs and put the money into GOOD USE and help put America in the lead again in the Space Frontier.

2013 is drawing to a close. Will 2014 be a better beginning for the United States of America ?

Re:Hope Nasa can help us on that (2)

EdgePenguin (2646733) | about 10 months ago | (#45744717)

Given how long it will take to chew through Gaia data (Essentially, as someone starting out in astrophysics, this mission could define much of my working life) there won't be another powerful astrometry mission for a while.

Why are you fixated on having NASA try to one-up ESA though? NASA has its own top end science missions planned, doing other things. If you are lucky and take care of your space agency, so of them might actually fly in space.

Re: Hope Nasa can help us on that (1)

Anonymous Coward | about 10 months ago | (#45744775)

Because "frontier." Americans have been conditioned since the dawn of the twentieth century to respond positively to the word "frontier" in rhetoric and funding proposals. It's part of the "Frontier theory" of history: basically, that America was exceptional and democratic because of its unsettled western edge, until it was finally settled, which made the exploration of "new frontiers" in technology and space the new site of American exceptionalism and freedom. It's the theory that consciously underpins the rhetoric of all NASA funding, but it's been around at least since the Chicago Exposition's evanescent Great White City gleamed in all its temporary plaster glory.

Re:Hope Nasa can help us on that (1)

Anonymous Coward | about 10 months ago | (#45745221)

It would be silly to try to one-up ESA on this. It would be much better to fund these missions (and to hell with the pork-barrel manned missions):
Mars Sample Return
Europa Clipper, esp. in light of the plumes
Terrestrial Planet Finder

Re:Hope Nasa can help us on that (0)

Anonymous Coward | about 10 months ago | (#45745577)

Given how long it will take to chew through Gaia data (Essentially, as someone starting out in astrophysics, this mission could define much of my working life) there won't be another powerful astrometry mission for a while.

Perhaps it would take a while. Or perhaps your precious scientific data would disappear at an alarming rate. [slashdot.org]

Re:Hope Nasa can help us on that (1)

Wootery (1087023) | about 10 months ago | (#45745663)

Don't know how these two are related...

Re:Hope Nasa can help us on that (1)

nojayuk (567177) | about 10 months ago | (#45746911)

The James Webb Space Telescope is the next big NASA space project although the funding has been on-off for the past decade, raising the final price and stretching the delivery time to 2018 and counting. It could still be cancelled by Congress to save money and help reduce the national debt. Europe is providing a number of instruments and an Ariane V launch for the project in return for access to the science.

The JWST is the last Big Space Science project on NASA's books though, all the other big observatories were cancelled or never got past the proposal stage. There are no plans to replace the Hubble with a similar visible-light observatory even in low Earth orbit, unless someone can rework those spare NRO Keyholes that were donated to NASA recently and find money to launch them.

Re:Hope Nasa can help us on that (2)

TangoMargarine (1617195) | about 10 months ago | (#45745863)

You're talking about not wasting money but then in the next breath that the U.S. has to "win at space"? Last I checked, we weren't in a cold war with Europe or anything. Just call this a win. We don't need to one-up them. I know it's a radical concept, but maybe we could all SHARE information about space.

Re:Total map size (1)

EdgePenguin (2646733) | about 10 months ago | (#45744723)

It will find galaxies, sort of. Gaia doesn't really care what it is looking at, it simply tags every point of light in its field that is bright enough. Things that aren't stars are then to be discarded when the data is processed. There was a recent paper published suggesting that some of these discarded galaxies could be surveyed in order to get even more science value out of Gaia.

Re:Total map size (2)

j-b0y (449975) | about 10 months ago | (#45744965)

Very little that Gaia observes is truly discarded -- just the main astrometric system needs a mix of stable, well behaved stars and very distant quasars, that could be between 10% and 50% of the objects detected. There will be an attempt to classify objects -- which you need to do in order to grab the quasars for the astrometric system

Re:Total map size (1)

EdgePenguin (2646733) | about 10 months ago | (#45746623)

I meant to say some of the data is discarded. The paper I read discussed reconstructing a galaxy images to take into account the information Gaia throws away before downloading it to the ground station.

Re:Total map size (0)

Anonymous Coward | about 10 months ago | (#45744117)

I imagine there are far more than 170 billion galaxies out there.

Re:Total map size (4, Informative)

wjcofkc (964165) | about 10 months ago | (#45744593)

While it is true that we don't know for sure how many galaxies there are in the Universe, 170 billion is likely low balling it a bit too much. The most widely accepted estimate stands at 500 billion - but still, this is murky water. A good article on how that number was arrived at can be found here:

500 Billion --A Universe of Galaxies: Some Older than Milky Way [dailygalaxy.com]

Re:Total map size (0)

Anonymous Coward | about 10 months ago | (#45745259)

And that's just a guesstimate on what we can see. There are bound to be many galaxies that are too faint or so distant that the light from them hasn't reached us yet. I would not be surprised if there were trillions of galaxies in the universe.

Re:Total map size (1)

wjcofkc (964165) | about 10 months ago | (#45746403)

Some have suggested that there may be trillions of galaxies in the universe at it's not a notion to be laughed at. There is the visible universe, and then there is the the rest. There is a tremendous amount of universe that we will never be able to see or measure because light or anything else will never ever reach us. It's just that far away. There are serious theories that what lies beyond may be very exotic, including different physical laws that allow for things such as single ultra-massive objects (or at least gravitation sources) that may be as large as the visible universe itself. Another popular theory is that there is a point in such far reaching space where our universe comes into physical contact with other universes that also serve as extreme attractive forces, there are indications in the cosmic microwave background that this is true. Although there is a lot of back and forth as to whether or not the phenomenon is real (appears it most likely is), the presence of the Dark flow [wikipedia.org] is an indicator that something bizarre is out there.

Re:Total map size (1)

Framboise (521772) | about 10 months ago | (#45748037)

Actually Gaia will map 1% of the stars, but a substantial (my guesstimate ~50%) volume of the region containing most of the stars, which will allow to map the principal structures of the Galaxy: its spiral arms and its stellar bar, as well as to constrain the distribution of dark matter. It is comparable to study one object, like the sun, to better understand all the stars; Gaia will map one galaxy well, ours, with the aim to better understand all spiral galaxies.

The size of a euro coin? (2, Funny)

yo303 (558777) | about 10 months ago | (#45744041)

What is that in Metric? Wait, I mean American?

Re:The size of a euro coin? (5, Funny)

Anonymous Coward | about 10 months ago | (#45744095)

What is that in Metric? Wait, I mean American?

Well, the diameter of a Euro is about 23.25 mm, giving it a surface area of about 425 mm squared. Given the ugly assumption that all 151,785,778 items in the library of congress are A4 sized (total SA ~ 9,466,878,973,860 mm squared), a Euro coin is about 4.5x10-11 of a Library of Congress.

I should probably do some work.

About the size of a quarter (1)

Chrisq (894406) | about 10 months ago | (#45744303)

Just slightly smaller than an American Quarter [air-tites.com] , not enough difference to affect this comparrison.

Re:About the size of a quarter (0)

Anonymous Coward | about 10 months ago | (#45744485)

We should express this in terms of the universal unit of area: it's 2.043×10^-14 times the size of Wales.

Re:The size of a euro coin? (0)

Anonymous Coward | about 10 months ago | (#45747755)

That is quite preposterous.
I've cancelled enough print jobs to know that A4 size is different from "Letter" size used here in Murica.
No way is LOC storing its information on A4

Re:The size of a euro coin? (4, Insightful)

idji (984038) | about 10 months ago | (#45744097)

This is a EUROPEAN satellite, and so a EURO is very appropriate.
Yes, the Europeans are going back to fundamental mapping of what is out there, like James Cook, Galileo, Johannes Kepler.

Onwards to L2 Gaia!!!

Re:The size of a euro coin? (0)

Anonymous Coward | about 10 months ago | (#45747987)

Yes, the Europeans are going back to fundamental mapping of what is out there, like James Cook, Galileo, Johannes Kepler.

Let's all hope that it doesn't all turn into a new prelude to colonization or a new inquisition...

Re:The size of a euro coin? (4, Funny)

Teun (17872) | about 10 months ago | (#45744101)

US$ 1.3639

Re:The size of a euro coin? (1)

rnturn (11092) | about 10 months ago | (#45745363)

Well, at least today it is. I prefer my units of measurement to be in wavelengths of an excited atom or, at the very least, the distance between two scratches on a platinum bar.

(I think the point folks have been trying to make it that it would have been much more informative to say a ``N millimeter'' coin/object/whatever. Much of the world has probably never seen -- or ever will see -- a Euro coin except, maybe, in a photograph.)

Re:The size of a euro coin? (0)

Anonymous Coward | about 10 months ago | (#45747745)

It REALLY doesn't matter exactly how big it is. It is a major coin from a stable major currency, with non-negligible value, so will be somewhere between 1.5 and 3.5cm. That is sufficient for what he wanted to convey. The guy was being reported on the BBC, and MOST Britons would have a pretty good idea how big a 1€ coin is (pretty similar to a 1£ coin actually). The guy was not trying to give a measurement for the US /. audience...

Re:The size of a euro coin? (1)

Anonymous Coward | about 10 months ago | (#45744109)

its diameter is .915 inch or 1.16 milli-furlongs :-)

Re:The size of a euro coin? (0)

Anonymous Coward | about 10 months ago | (#45744119)

What is that in Metric? Wait, I mean American?

The size (diameter) of the one euro coins in metric is approximately 25 mm - in "American" units is roughly the same as a cap from a soda bottle..,
(yes, i am Greek... but don't hate me, i love 'Murica!)

Re:The size of a euro coin? (0)

clickclickdrone (964164) | about 10 months ago | (#45744133)

(yes, i am Greek... but don't hate me, i love 'Murica!)

Are you sure you're European?

Re:The size of a euro coin? (-1)

Anonymous Coward | about 10 months ago | (#45744229)

Most Greeks/Europeans pretend to "hate" America.
But even the Socialists/Communists -especially them!- (and we have plenty of them -in Greece and Europe-... unfortunatly) that are obligated by their ideology to hate USA -and everything and everyone else! - are the bigest supporters of the American economy... they just can't live without American stuff!
To be honest there are some reasons that justify -remember: i am a Greek- some of that "hate" from the Greeks (but not other Europeans, as they are guilty themselves) since Americans choose to support those that are against the Western Civilization... the one we Greeks... created (!!!) - but every Greek that rants about them understands how a world without them would be and knows who the real enemy is.

Re:The size of a euro coin? (0)

Anonymous Coward | about 10 months ago | (#45744273)

the Western Civilization... the one we Greeks... created (!!!)

Debatable. At least you were able to tank your civilization in a matter of few recent years, so congrats for that.

Re:The size of a euro coin? (0)

Anonymous Coward | about 10 months ago | (#45744337)

the Western Civilization... the one we Greeks... created (!!!)

Debatable. At least you were able to tank your civilization in a matter of few recent years, so congrats for that.

Everything is debatable - but in /. story about "Gaia"... we Greeks win!

Re:The size of a euro coin? (1)

Chrisq (894406) | about 10 months ago | (#45744307)

Most Greeks/Europeans pretend to "hate" America. But even the Socialists/Communists -especially them!- (and we have plenty of them -in Greece and Europe-... unfortunatly) that are obligated by their ideology to hate USA -and everything and everyone else! - are the bigest supporters of the American economy... they just can't live without American stuff!

A bit like the American tea-party and Chinese products

Re:The size of a euro coin? (3, Insightful)

Anonymous Coward | about 10 months ago | (#45744343)

Wow, what a sweeping generalization. Most people around here (NW-Europe) appreciate americans. It seems to me the ones spewing ideological rants about the US, are those who never worked with/visited/befriended americans. We do, however, scratch our heads at your fervent opposition to social security, as this could really boost the productivity and prosperity of your middle class. That middle class which could probably generate more demand than your beloved 1%.

Re: The size of a euro coin? (1)

loufoque (1400831) | about 10 months ago | (#45744453)

Northern Europe is indeed more friendly towards the US than Southern or even Western Europe.

Re: The size of a euro coin? (0)

Anonymous Coward | about 10 months ago | (#45744759)

Yet the U.S. is not friendly to any of those countries.

Re: The size of a euro coin? (1)

peppepz (1311345) | about 10 months ago | (#45747229)

Why do you say so? I live in Southern Europe and people here generally consider the US as the source of everything that's modern and cool, a feeling which is widely reflected by our foreign policy.

Re: The size of a euro coin? (1)

loufoque (1400831) | about 10 months ago | (#45762075)

Because Southern Europe tends to like capitalism less, which is what the US embodies.

Re: The size of a euro coin? (1)

peppepz (1311345) | about 10 months ago | (#45765159)

Putting together under the same label the whole countries that comprise "southern europe" is a strong operation to begin with. As is defining a single label for "capitalism", for instance northern europe's rhenish capitalism is quite different from that of the USA. Politically, countries of southern europe have never been ruled by radical left-wing governments, while all of them have been ruled for some time by right-wing dictatorships in anti-communist stance. Now if you say that they haven't been able to implement and maintain a healthy modern capitalism system, we agree - I think that I live in the worst place on Earth to start a new business. But this doesn't mean that the majority of their population have a dislike for the USA or reject their influence; at least where I live, old people see them as a powerful ally that helped them get out of the post-WW2 misery, and young people receive them from the media as the only cultural example of how to obtain progress and wealth.

Re:The size of a euro coin? (0)

Anonymous Coward | about 10 months ago | (#45745247)

The US economy is about 70% consumption-based. Exactly how much more demand do we need?

Re:The size of a euro coin? (1)

TangoMargarine (1617195) | about 10 months ago | (#45745895)

Paradoxically, the Republican voter base loves love Social Security. They just don't love social security.

Re:The size of a euro coin? (1)

Teun (17872) | about 10 months ago | (#45744409)

Please keep that 'Most Europeans' out of the story, heck, I bet that given the chance a lot of Greeks would happily have some holidays in the states.

Now that doesn't mean a lot of Europeans are happy with the recent (last ~15 years) US government's politics re. their 'friends'.

Re:The size of a euro coin? (0)

Anonymous Coward | about 10 months ago | (#45744599)

Please keep that 'Most Europeans' out of the story, heck, I bet that given the chance a lot of Greeks would happily have some holidays in the states.

I don't think any Greek would choose USA for his holidays (Greeks live in Greece dude... the other people choose Greece for their holidays!), but many Greeks happily choose USA as a place to live and prosper (and become very patriotic towards USA - even if they always feel nostalgic about Greece).
I don't "keep that 'Most Europeans' out of the story" because i think i know well us Europeans - we constantly PRETEND to hate USA!

Re:The size of a euro coin? (1)

EdgePenguin (2646733) | about 10 months ago | (#45744691)

The Bush years were very trying on European patience, but there really isn't widespread animosity to Americans here. Please, don't let it stop you visiting. No, really, we are totally fucked here, bring your precious dollars ASAP. Help us!.

Re:The size of a euro coin? (1)

angel'o'sphere (80593) | about 10 months ago | (#45744993)

the Western Civilization... the one we Greeks... created (!!!) That is a myth.
History likely had run pretty similar when Xerses had won over the greeks.

are the bigest supporters of the American economy... they just can't live without American stuff!
That is nonsense. The only american products I own is my Apple stuff ...
And I don't know anyone who owns anything made in america. Yes, ofc. you see the occasional american car on the streets and yes I guess many european air lines fly Boings ...

Re:The size of a euro coin? (0)

Anonymous Coward | about 10 months ago | (#45745609)

Ever watched musicals/tv-shows/cinema movies and listened to music? Idiot!

Re:The size of a euro coin? (1)

clickclickdrone (964164) | about 10 months ago | (#45744445)

Modded down for a joke? Man you guys are up tight.

Re:The size of a euro coin? (0)

Anonymous Coward | about 10 months ago | (#45744547)

Modded down for a joke?

... that it wasn't even a "joke"?

Man you guys are up tight.

... no, just Socialists/Communists - it's /. dude!

Sign: Your Greek/European parent...

Re:The size of a euro coin? (0)

Anonymous Coward | about 10 months ago | (#45748669)

It only gets modded "funny" if it makes someone grin and isn't too offtopic.

Re:The size of a euro coin? (0)

Anonymous Coward | about 10 months ago | (#45744141)

That's between a copper half cent and a two cent. I remember when I first bought a hooker with few of those half cents at the Burns Lane, Charleston. Those were the days!

Re:The size of a euro coin? (1)

KritonK (949258) | about 10 months ago | (#45744163)

In Metric, it is 23.25 mm.

In American, it is 0.95836768342951360263 times the diameter of a quarter. Or, in more standard units, 0.00021188757655293088 football fields. Approximately.

Re:The uncertainty is 775 miles at Alpha Centauri (2)

AmbiLobe (2999721) | about 10 months ago | (#45744949)

The angle of 7 u arc sec is 3.3 x10 ^-11 radians . The distance is 4 light years x 5.87 x 10 ^12 miles per LY . Product is 775 miles resolution of the position of a star 4 Light years away. Astounding accuracy !! congrats !

Re:The uncertainty is 775 miles at Alpha Centauri (0)

Anonymous Coward | about 10 months ago | (#45745257)

That's the uncertainty in the sideway position only.
sideway uncertainty = (3.3 x10^-11) * (4 LY) = 775 miles

Most of the error in the position of a star is in the depth direction. That error is given by a different formula:
depth uncertainty = (3.3 x10^-11) * (4 LY)^2 / (2 AU) = 98,150,000 miles

Re:The size of a euro coin? (0)

Anonymous Coward | about 10 months ago | (#45744177)

1.36 US dollars.

Re:The size of a euro coin? (1)

jimshatt (1002452) | about 10 months ago | (#45744287)

Given how close the moon is, this doesn't sound very accurate at all. Luckily, Gaia is still very confident. Good girl.

Re:The size of a euro coin? (1)

Neil Boekend (1854906) | about 10 months ago | (#45744331)

Woa, so you know how to build a sensor that can pinpoint a location at a distance of 384,400 km more precise than +/- 23.25 mm? Color me impressed!

Re:The size of a euro coin? (2)

yo303 (558777) | about 10 months ago | (#45744431)

This being a European project you should be coloured impressed.

Re:The size of a euro coin? (1)

Carewolf (581105) | about 10 months ago | (#45744859)

This being a European project you should be coloured impressed.

Sure, I shouldn't kulør d'impressed seid?

Re:The size of a euro coin? (1)

GauteL (29207) | about 10 months ago | (#45744865)

I was wondering how impressive it was and attempted to resolve this with trigonometry to find the likely error distance 1 light year away.

This got me in trouble with precision (the angle is of the order 1.0e-11 in Radians) but knowing that the angle is a constant here, the error should scale linearly with the distance.
If we use 400,000 km as the distance to the moon, 1 light years is roughly 2.0e7 times the distance to the moon (Google search calculator).

Thus an error of 20mm = 2.0e-5 km error at 400000 km should give around 2.0e7 * 2.0e-5 km =~ 400 km, meaning at 1 light years away, their error is roughly on par with how far away Ryan Air puts you from your real destination.

Re:The size of a euro coin? (1)

jimshatt (1002452) | about 10 months ago | (#45750729)

Hmm, that is impressive. Thanks for doing the math. I was (obviously) going on a gut feeling there :)

Re:The size of a euro coin? (1)

Teun (17872) | about 10 months ago | (#45744447)

Given how close the moon is,

Now I appreciate the US concept of distance is, especially for those from the mid-west, different to that of someone living in say Luxembourg or Belgium but to call the moon close is a bit of a stretch.
I mean, even with your low fuel prices such a 480,000 mi round trip might get expensive...

Re:The size of a euro coin? (0)

Anonymous Coward | about 10 months ago | (#45751607)

You're nose is a bit of a stretch, ass.

Re:The size of a euro coin? (0)

Anonymous Coward | about 10 months ago | (#45744809)

What is that in Metric? Wait, I mean American?

You must be joking. We're talking about stars & galaxies here, so let's put it in relevant units.

A Euro coin is 23.25 mm, that is 0.7535 attoParsecs or 7.755*10^(-11) light seconds or 2.4578*10^(-18) light years.

For you quantum physicists: that is 1.439*10^33 planck length.

Re:The size of a euro coin? (0)

Anonymous Coward | about 10 months ago | (#45745271)

i'd like to know *which* euro coin. there are more than one.
you're just assuming that the one euro coin was intended.

Next step. (0)

Anonymous Coward | about 10 months ago | (#45744209)

Next step: Galaxia

Re:Next step. (0)

Anonymous Coward | about 10 months ago | (#45744957)

Next step: Galaxia

You mean Galaga?

Boldly Going! (0)

Anonymous Coward | about 10 months ago | (#45744589)

On a Five Year Mission, no less. Quick, establish the United Earth Space Probe Agency immediately so the Americans can claim to be involved while they contribute nothing.

The real test... (1)

Circlotron (764156) | about 10 months ago | (#45744683)

...is whether it can detect Apollo 11 mission stuff on the moon. That would shut a few mouths. The Hubble telescope lacks sufficient resolution in the visible light range.

Re:The real test... (1)

j-b0y (449975) | about 10 months ago | (#45744945)

Well, Gaia won't ever observe the Moon, nor Venus and Mercury which are always on the sun-ward side of the solar-shield. Jupiter is so bright that it really messes with the detectors when it transits the focal plane, but it should be possible to do some interesting general-relativity experiments with the light-bending effects of Jupiter's mass for stars that are close (not not too close) to Jupiter when Gaia observes near it.

Re:The real test... (1)

Framboise (521772) | about 10 months ago | (#45747959)

In fact Gaia is sufficiently sensitive that General Relativity light deflection due to the sun and planets must be taken into account in all directions!

Re:The real test... (0)

Anonymous Coward | about 10 months ago | (#45745043)

...is whether it can detect Apollo 11 mission stuff on the moon. That would shut a few mouths. The Hubble telescope lacks sufficient resolution in the visible light range.

Why should moon landing deniers believe the results from Gaia?

ESA (and also the Chinese space agency with their Jade Rabbit) must be *in* the conspiracy (they were *forced* into it by the reptilians).

Excellent! (4, Informative)

Hartree (191324) | about 10 months ago | (#45745295)

This is a mission I've been watching and waiting for for a while. The original Hipparcos mission did this sort of mapping for a much smaller volume of space.

Think of this as being like how finding the precise latitude and longitude of a large number of places on earth would have been to navigators of a much earlier era. No big new ideas, but it makes navigating so much easier and precise.

This does this for astronomy and cosmology in a greatly expanded region of space.

Something some don't realize is that our measurements of distance to stars and other objects in astronomy are very indirect. We use red shift to measure it in many cases, but that's an indirect method that relies on assumptions and estimates of the Hubble constant.

We also use what are called "standard candles". These are objects we know the brightness of from the physics of the processes going on. Certain kinds of supernovae are some of the best known. But, again, like measuring the distance to the next town by how bright the streetlights are, it's indirect and can have errors from intervening dust, for example..

This will use parallax, the same method as used in surveying to find distance from the change in angle between two separated observations of a far object. It's a direct method that relies on few assumptions.

dollars (0)

Anonymous Coward | about 10 months ago | (#45748035)

1.01 billion dollars.
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