Radio telescope on moon's far side will peer into universe's 'Dark Ages'

[Admin]

A few years from now, a small radio telescope on the far side of the moon could help scientists peer into the universe's ancient past.

Radio telescope on moon's far side will peer into universe's 'Dark Ages' : Read more

 

[rod]

"The Dark Ages refers to a time in the early universe, between about 400,000 and 400 million years after the Big Bang, before stars and galaxies began to fully form. From the far side of the moon, LuSEE-Night will use onboard antennas, radio receivers and a spectrometer to measure faint radio waves from the Dark Ages, in search of what scientists are calling the Dark Ages Signal. "So far, we can only make predictions about earlier stages of the universe using a benchmark called the cosmic microwave background. The Dark Ages Signal would provide a new benchmark," Brookhaven physicist Anže Slosar said in a statement(opens in new tab). "And if predictions based on each benchmark don't match, that means we've discovered new physics."

My note. Using cosmology calculators, the redshift for 400,000 to 400 million years after BB is 1050 to about 11.5 or so. JWST already reports galaxies in the 11-13 redshift range now. It will be interesting to see the confirmation of H-alpha line and H1 21-cm line too, demonstrating that the early universe was indeed filled with hydrogen gas when the CMBR appeared as light. There is the issue of comoving radial distances too for these large redshifts for the Dark Ages and how fast space is expanding, multiples of the speed of light.

 

[Helio]

Thanks Rod for those redshifts.

H-alpha has too little redshift to reach the radio band.

 

[Unclear Engineer]

H-alpha has too little redshift to reach the radio band.

Is there some band of energies that we can't detect? I don't think so. We are detecting the "Cosmic Microwave Background" which is supposedly black body radiation from hydrogen at 1080 red shift. So, can't we devise some sort of "radio" or "IR" telescope to see whatever frequencies we need to see in the 1080 to 11 range of redshifts?

I agree that getting them to work on the far side of the Moon is an engineering puzzle to be solved.

For that matter, it would be nice if this article had explained how data taken by a robotic telescope on the far side of the Moon will send its data to human analysts here on Earth's surface, since its location is intentionally chosen to be out of direct radio line of sight.

And there is also the question about how long it will be before humans have put so many satellites into lunar orbits that we radio-contaminate this "quiet zone" out of usefulness.

 

[Helio]

Is there some band of energies that we can't detect? I don't think so. We are detecting the "Cosmic Microwave Background" which is supposedly black body radiation from hydrogen at 1080 red shift. So, can't we devise some sort of "radio" or "IR" telescope to see whatever frequencies we need to see in the 1080 to 11 range of redshifts?

They’re already built. A microwave telescope was being built to find the CMBR, but a larger one accidentally found it first, The JWST can handle the z = 11 and greater.

For that matter, it would be nice if this article had explained how data taken by a robotic telescope on the far side of the Moon will send its data to human analysts here on Earth's surface, since its location is intentionally chosen to be out of direct radio line of sight.

Good question. Perhaps a small repeater could be plopped down, The combo use at L1 & L2 would work fairly well, but expensive I would think.

I’d bet there will be a nice base on the far side, someday.

 

[Unclear Engineer]

Considering the large amount of data that a telescope takes-in, it seems to me that it will either require a continuous communication with an analysis center on Earth or a really massive data storage facility on the far side of the Moon. I doubt we are going to run a wired cable around the Moon from the far side to the Earth-facing side - and putting in microwave relays seems like exactly what we are trying to get this telescope away from.

 

[Helio]

Considering the large amount of data that a telescope takes-in, it seems to me that it will either require a continuous communication with an analysis center on Earth or a really massive data storage facility on the far side of the Moon. I doubt we are going to run a wired cable around the Moon from the far side to the Earth-facing side - and putting in microwave relays seems like exactly what we are trying to get this telescope away from.

Perhaps the base, whether this one or those to follow, would be located where the Earth is just below their horizon, with libration considerations. Thus a low-power laser should be able to transfer to the repeater that has a direct shot at Earth. Perhaps a high-powered laser could send this to Earth scopes directly. If a scope at the McDonald obs. can bounce a laser beam off the Moon and measure this feeble signal on its return (giving distance), then how much easier will it be to receive one emitting from the Moon?

I'm just guessing, of course.