Military smallsats

[Blackstar]

The U.S. military has had an interest in small satellites at several points in time, most notably the late 1980s and again in the past decade with Operationally Responsive Space.

I have a new article that refers to the late 1980s interest in small satellites.

[Blackstar]

http://www.thespacereview.com/article/2104/1

The Stacksat saga story
by Dwayne A. Day
Monday, June 11, 2012

Most satellites end up as nothing more than footnotes in unread history, long forgotten by all but those who built and flew them. But even the forgotten and obscure satellites can tell part of a larger story. In April 1990, the US Air Force launched a trio of small experimental spacecraft. Although not particularly notable, they typified a then-emerging trend for very small satellites, a trend that has reappeared and faded several times throughout the history of the American space program.

[jongoff]

Blackstar,

Thanks for a great article. I've only been actively following space stuff since the late 90s, so the only way I find out about some of these earlier, less-well-known projects is by articles like this one.

~Jon

[Blackstar]

Just keep in mind that everything repeats. Every argument, every debate, every idea that you see today existed in some form in the past.

[Skyrocket]

Great work, Blackstar (as usual )

Also on the same theme - there were also two MACSAT small communications satellites, which were also built on the same DSI bus (called MAESTRO). These two satellites were launched about one moth later stacked on a Scout launch vehicle and looked very similar to the three Stacksats.

http://space.skyrocket.de/doc_sdat/macsat-1.htm

[Blackstar]

Thanks. I knew about MACSAT, but did not know that they were the same bus.

There was a flurry of activity in this field that quickly died out:

STACKSAT
Microsats
MACSAT

and probably a few others.

That did enable DSI to get into the satellite business and that company later became part of Orbital Sciences. I don't know if these smallsats ever really accomplished anything of value, however.

[kevin-rf]

Okay, I really enjoyed the read on that. Thanks Blackstar, it was an excellent article.

[js117]

http://www.thespacereview.com/article/2104/1

The Stacksat saga story
by Dwayne A. Day
Monday, June 11, 2012

Most satellites end up as nothing more than footnotes in unread history, long forgotten by all but those who built and flew them. But even the forgotten and obscure satellites can tell part of a larger story. In April 1990, the US Air Force launched a trio of small experimental spacecraft. Although not particularly notable, they typified a then-emerging trend for very small satellites, a trend that has reappeared and faded several times throughout the history of the American space program.

Nice article well written.

Aren't the the largersats bigger because they involve optics ( mirrors).
The small ones as you said wer used for data only.

[Blackstar]

1-Nice article well written.

2-Aren't the the largersats bigger because they involve optics ( mirrors).
The small ones as you said wer used for data only.

1-Thank you. That is most kind.

2-Not necessarily. What about satellites that don't require optics? There are very big comsats.

It is true that some missions require certain size apertures. For instance, if you want high resolution imagery, you need a big mirror. If you want to detect very faint signals, you need a big antenna. However, even in those cases, you should ask if the requirements are really legitimate. Do you really need that capability or can you settle for something smaller?

Certainly some simple requirements can be met with simple, and small, and therefore relatively cheap, satellites. The question is if it is possible to get more bang for the buck out of a small satellite by using advanced electronics, sensor technologies, etc. There have been times (late 1980s, late 1990s-today) when people have argued that you could indeed get more bang for the buck with small satellites. (Of course, you could also get more bang for the buck by using these advanced technologies with the big satellites as well. But the point is that you may be able to satisfy your requirements with a smaller satellite that now has greater capabilities than before.)

[jongoff]

Just keep in mind that everything repeats. Every argument, every debate, every idea that you see today existed in some form in the past.

Well, history never repeats itself, but it often rhymes. I think part of the hope is that as various technologies and developments outside of aerospace progress, that some old ideas do actually eventually reach the point where they now make sense. One of the problems of having a field full of visionaries is that you get a lot of people coming up with good ideas before all the pieces are ready to implement them, and then when that happens when the pieces are finally in place where it can be implemented a lot of people will argue that "oh but we've tried that once in the past and it didn't work".

~Jon

[jcm]

Thanks. I knew about MACSAT, but did not know that they were the same bus.

There was a flurry of activity in this field that quickly died out:

STACKSAT
Microsats
MACSAT

and probably a few others.

That did enable DSI to get into the satellite business and that company later became part of Orbital Sciences. I don't know if these smallsats ever really accomplished anything of value, however.

Also REX (June 1991)   RADCAL (Jun 1993)  REX II (Mar 1996)
Possibly ACRIMSAT (Dec 1999) used a derivative
Microsat 1-7 were a bit smaller - the MAESTRO bus was also called Ministar, and the Microsats were called Picostar  at one stage

[kevin-rf]

Nice article well written.

Aren't the the largersats bigger because they involve optics ( mirrors).
The small ones as you said wer used for data only.

I agree entirely with your first point.

On your second point, by many definitions Corona (KH-1 thru KH-4b) fall under the category of small sats. and return very important data. Easily one of the most important military satellite platforms of the 1960's. Funny that the KH-9 replacement was one of the largest large sat of the 1970's. 

[Blackstar]

On your second point, by many definitions Corona (KH-1 thru KH-4b) fall under the category of small sats. and return very important data. Easily one of the most important military satellite platforms of the 1960's. Funny that the KH-9 replacement was one of the largest large sat of the 1970's. 

I think that before we go too far down that road we should establish some definitions. CORONA was not "small" relative to other robotic payloads at the time.

[Blackstar]

Just got contacted by somebody involved in the original DSI smallsats. He reminded me that they went on to produce a LOT of smallsats. I'll have to amend my story a bit, but that's why I always ask for people with more info to contact me.