The lower the frequency, the larger the wavelength and thus the larger the cupola needed to detect it. That's why radiotelescopes are on earth, they are HUGE.

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amluto 6 hours ago | parent [-]

Radio telescope dishes are huge so that they can receive (or even transmit in the case of Arecibo, which is gone now) a narrow beam. At long wavelengths you need something huge to get a narrow beam.

But you can also use multiple, much smaller antennas to synthesize a narrow beam, and those little antennas are often dishes but can also be very simple and rather small antennas.

	▲	adgjlsfhk1 an hour ago \| parent [-]
		interferometry is good for seeing small objects, but not faint objects. for faint objects there's nothing that works better than a giant dish