14 votes

Can we use something like RADAR to detect asteroids?

Yes, radar is one of the useful tools for detecting and observing asteroids. It is however most effective at closer ranges, like near-earth asteroid, since sending out a radio wave and bouncing it ...
12 votes
Accepted

Can we use something like RADAR to detect asteroids?

The way the question is formulated can lead to contradictory answers. It can be understood as: since a RADAR can "see" in the dark, can it be used to detect objects that are not illuminated ...
  • 2,679
12 votes
Accepted

Arecibo: Advantages of Giant Dish?

Radar Astronomy of solar system objects is actively pursued using FAST, Goldstone 70 m dish, Green Bank and until now Arecibo (some in receive mode only) in order to explore asteroids as they pass ...
  • 147k
8 votes

Arecibo: Advantages of Giant Dish?

It's not a one-size-fits-all situation: Resolving power. This is based on the diameter of the collector and greatly favors a multiple dish approach as the distance between the dishes counts--two ...
7 votes
Accepted

How do the small radio receivers on space probes catch enough of a signal to communicate with us?

We communicate via radio, as you note, but it's not quite as hard as your question makes it sound. Don't get me wrong, it's still an amazing feat of engineering, but we can walk through how it's ...
6 votes

Has VLBI been done using any space-based receivers besides Spektr-R?

KRT-10 radiotelescope in July 1978 The world's first VLBI-experiment was conducted with a KRT-10 space-based radiotelescope and a RT-70 radiotelescope in Evpatoria, Crimea. https://ru.wikipedia....
  • 7,733
6 votes
Accepted

How is Spektr-R doing these days?

On May 30 there had been a meeting concerning the status of Spektr-R. Afterwards Roscosmos published a statement at https://www.roscosmos.ru/26397/ Here a machine translated version using www.DeepL....
6 votes

Has VLBI been done using any space-based receivers besides Spektr-R?

I found a 2008 citation of space-based VLBI 'by using a radio antenna in earth orbit. This has indeed been accomplished with the Japanese satellite "HALCA" (Highly Advanced Laboratory for ...
  • 161
5 votes

Arecibo: Advantages of Giant Dish?

Sensitivity: in an ideal world, you need to increase the number of nodes in an array by 2 orders of magnitude to increase sensitivity by 1 order of magnitude. Absolute best case, you need 100 dishes ...
5 votes
Accepted

What's the status and timeline for Millimetron? (Russia's 10m Deployable Antenna cooled to 6 K Earth-Space VLBI)

Provisional launch date 2029 https://millimetron.ru/en/ This project is directly related to the P-2500 (RT-70) radiotelescope at the Suffa radioobservatory. This modification of the RT-70 radio ...
  • 7,733
4 votes
Accepted

Are these good specifications for a X-Band High Gain Antenna?

Doing a scaling process from the performance of the telecommunications ("telecom") system of NASA's Cassini spacecraft at Saturn, I estimate the system you describe could support a data rate ...
  • 18.1k
3 votes

Has VLBI been done using any space-based receivers besides Spektr-R?

JAXA had a radio telescope mission named HALCA: HALCA was launched by M-V-1 on February 12, 1997. As a radio astronomy satellite, it conducted various engineering experiments including deployment ...
  • 122k
3 votes
Accepted

Specifications of a High Gain Antenna

So we are looking to specify an X-band high-gain antenna for the communication on a Entry-Descent-Landing vehicle at circa 10 AU, and want to determine the diameter of the antenna, power usage, ...
  • 147k
3 votes

Was it a "Soviet military satellite not in any of the catalogs?"

As @Antony X and @Abacus Lever already said, the "secret soviet satellite" is referred to an earlier event, not to the 2015 observation. I could not find what exactly "secret satellite&...
  • 8,876
3 votes
Accepted

Radio Telescope / DSN Node in L4 and/or L5

One significant issue is we cannot maintain a fixed baseline in this way. L4 and L5 are indeed stable, but in space (or rather, in the space that actually exists) "stable" does not mean ...
  • 8,075
2 votes
Accepted

Following KRT-10 aboard Salyut-6, have there been any other radio astronomy observations from a space station or crewed capsule?

Soviet experiments on manned spacecraft have found that this type of spacecraft is not suitable for astronomical observations. Human activity inside a ship or orbital station creates vibrations that ...
  • 7,733
2 votes
Accepted

Is the recently discovered VLF-induced radiation barrier in any way important or useful?

That paper "Anthropogenic Space Weather" runs to 55 pages, but only 5 pages discuss VLF impact on the ionosphere (chapter 8), while 35 pages (chapters 2-7) discuss EMP from high altitude nukes. This ...

Only top scored, non community-wiki answers of a minimum length are eligible