Gigantic Chinese telescope opens to astronomers worldwide

[latchkey]

Found it on Google Maps:

https://www.google.com/maps/place/Dawodang,+Pingtang,+Qianna...

[milankragujevic]

There's a cool 360 image -- https://goo.gl/maps/v4VkHhGmp5mfFk457 -- from the (near) center of the telescope.

[arbuge]

Previous record holder was the well-known Arecibo telescope at 305m diameter:

https://en.wikipedia.org/wiki/Arecibo_Observatory

500m may not seem like a huge improvement over that but here's a picture that puts it in perspective:

https://en.wikipedia.org/wiki/Five-hundred-meter_Aperture_Sp...

[ajross]

Lost in the announcement is the fact that they're opening this for global research because... they don't really have anything queued up yet. High-aperture radio astronomy doesn't really have a hook right now.

Arecibo was built half a century ago now, and ever since has remained (by far) the most sensitive radio telescope available. Yet... it hasn't found much that we didn't already know about. FAST seems likely to sit in the same realm: it'll be able to see known phenomenon farther away, but that's about it.

We have plenty of radio sensitivity right now, what we need is broader coverage to pick up transient things like FRB's, and (as always) longer baselines for VLBI work (e.g. the Event Horizon "Telescope"), both of which which mean more dishes, not one giant dish.

[SiempreViernes]

I think this is a bit unfair: better point sensitivity has obvious scientific value, it just isn’t the most cost effective radio project if you have expertise in building arrays already.

And those extragalactic pulsar studies they hope to do sound pretty nice.

[tremulens]

Is there anything preventing them from tuning up FAST so it's as or even more sensitive than Arecibo? Like, is it just a matter of better sensors or dish design? Maybe we don't need it, but cleaner data would be nice at least.

[tempestn]

Sorry, I couldn't help myself.

Real missed opportunity there to name it the Five-hundred-meter Aperture Radio Telescope. Bonus points if they detect an interesting pulsating signal and do as was done with the gravitational waves, shifting it into the audio band...

[peterlk]

I'm hopeful that the scientific community will be happy to colloquially refer to this as the FARTiscope

[Ididntdothis]

”The 1.2-billion-yuan (US$171-million) telescope,”

This price is surprisingly low compared to other big science projects.

[cbanek]

Seriously low. I'm impressed. Also it said in the article it only took half a decade to build, which is also pretty impressive for such a large instrument.

[bigpumpkin]

I wonder whether this is because they don't need to have a highly specified lens found in conventional telescopes?

[jkmcf]

Labor costs are much lower?

[forgingahead]

Meanwhile, TMT is still facing tons of opposition: https://www.hawaiinewsnow.com/2019/09/26/solidarity-mauna-ke...

[CharlesColeman]

> Meanwhile, TMT is still facing tons of opposition

Which is one of the things that makes democracy and civil rights great: different people can express different perspectives and influence the decisions made.

[sschueller]

Why would anyone have a problem with a telescope? They produce almost no light and are also very quiet. I doubt the produce much traffic unless it's some museum as well.

Also putting a telescope near your home probably hinders addition of other things that produce light pollution or am I wrong?

[kuu]

It should go to the Canary Islands, where there is 100% support:

https://physicsworld.com/a/thirty-meter-telescope-forges-ahe...

[haberman]

It appears that there was widespread support 18 months ago, even among Native Hawaiians: https://www.westhawaiitoday.com/2018/03/26/hawaii-news/poll-...

But the same article says that in 2016 support was much lower.

I wonder what is happening to change the level of support over time. Maybe the 2018 poll was just an anomaly.

The parent article (hawaiinewsnow.com) makes me sad, because it sounds like opposing the telescope is becoming a way of feeling cultural identity. The desire to feel a part of something is satisfied by mobilizing in opposition to something. I would like to believe that cultural expression and belonging can coexist with modern scientific inquiry. From this page it sounds like the project has done a lot of work to minimize the impact and do community outreach: http://www.maunakeaandtmt.org/facts-about-tmt/

[chongli]

Surprised to see no mention of tourists or cellphones. We learned about this telescope in astronomy class on Tuesday and our professor said the place was inundated with so many tourists that it was impossible to get any useful data due to the noise generated by all the cellphones. Part of the reason the telescope was built in such a remote area was to reduce the amount of radio noise from terrestrial sources.

[mp8]

That's surprising. I went there recently, and you aren't permitted to bring any electronic devices whatsoever - you have to leave them in a locker and then take a ~30 minute bus ride to the telescope.

They're also very strict about checking: you have to go through two different x-ray machines to check you didn't sneak any electronics through.

[simion314]

Maybe the tourists are present only a few hours in certain days. The article mentioned some discoveries so it must be working.

[yawz]

Did they build a football/soccer field next to it so that we can realize how gigantic it is by looking at the pictures?

[benburleson]

More likely so the workers had some recreation while on assignment!

[cblum]

I just came here to comment on that :)

[godelski]

This is a smart move by China. There are a lot of reasons to do big science projects other than accomplishing the science itself. One of the biggest is that you get a lot of the smartest minds around the world in the same place as one another. The country that is hosting them will receive more benefits than the other countries participating (though everyone wins in some way). You also are more likely to get the spinoffs that always come off from working on difficult projects.

China is also building a super collider that's larger than CERN. The big question though is if they plan on doing an international effort (and if so, can they attract international scientists while operating an authoritarian state?) or if they plan on doing it only nationally (seems much harder to do and not as effective).

[SiempreViernes]

They have loose plans for building one, there is no current construction, or indeed even a definitive descision. Even when the chinese decide is uncertain: could be next year, could be in three years(1). The only thing that exists is a conceptual design, that isn’t even sited!

(1): https://indico.ihep.ac.cn/event/9832/session/0/contribution/...

[kayaeb]

FAST is actually having difficulty hiring (on-site specialists like operations director) the smartest minds because it's in a jungle in small-town China.

But yes, overall China is executing an excellent "brain drain" (not meant in a negative sense) by being willing to invest in these "keystone" projects when other countries are tightening budgets.

[tempguy9999]

> There are a lot of reasons to do big science projects other than accomplishing the science itself

One is national prestige. I'm not sure that's a good reason (if that's what's happened here).

[aritmo]

What is the percentage of the sky it can observe? Should be fairly small.

[Iv]

This telescope moves the sensor head across the surface, changing the actual angle of the observation. The big poles around it are what suspends the head over the surface. It has actually a huge angle of observation. According to WP, 60° in its small 200 m aperture and 26.4° in its 300m aperture.