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21 votes
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What was the outcome of the launch of ZUMA by SpaceX, to the best of the public's knowledge?

What is known: SpaceX issued a statement saying that the Falcon 9 performed as intended An object was seen with spinning plumes that is assumed to be a Falcon 9 upper stage post-thrust fuel dump. ...
PearsonArtPhoto's user avatar
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15 votes
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Are cubesats deployed with fully discharged batteries? Even those on Sherpa?

All cubesats that I have personal knowledge of (including the Planet Labs fleet) were launched with partially charged batteries, typically at around the 50% level that minimizes degradation in storage....
pericynthion's user avatar
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10 votes

Can a blimp dead drop on Mars or Earth this way?

NASA is working on an inflatable heat shield. Not quite a blimp, but a heat shield that's inflatable to a size much larger than the probe it's attached to. The extra area helps decelerate the ...
Hobbes's user avatar
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10 votes
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Have there been individual satellites that have been deployed and recovered more than twice?

There have been a few. One notable one was ASTRO-SPAS. This satellite was deployed from a space shuttle, flew independently making astronomical observations, and was retrieved on four separate ...
Organic Marble's user avatar
9 votes
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How was it difficult for the PSLV to launch a record of 104 satellites?

The key phrase is "satellites separated from the final stage safely without colliding into each other" Let's break that into two pieces: Satellites Separated From Each other- In order to do this, it ...
PearsonArtPhoto's user avatar
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9 votes

What kinds of things have been tossed out of the ISS?

An Orlan spacesuit! aka SuitSat 1. The tool bag was lost by Heidemarie Stefanyshyn-Piper during the STS-126 mission, who was a fine astronaut and deserves to be remembered for more than this ...
Organic Marble's user avatar
8 votes

Why does the Falcon 9 launch heavier payload in LEO than Ariane V and the other way around for GTO?

That Wikipedia article may be incorrect. There are several versions of the Ariane 5 with different performance figures, and the article seems to mix 2 of them. the Ariane 5 ES ATV, which is ...
Hobbes's user avatar
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7 votes

What kinds of things have been tossed out of the ISS?

To add to the list, don't forget the large Ammonia Tank that Clay Anderson jettisoned in his EVA (23 Jul 2007): Source: The Living Moon Further jettison 27th January; Glover has just tossed the ...
Brian Tompsett - 汤莱恩's user avatar
7 votes
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Are the cubesats deployed from the ISS always directed "nadir and retrograde"?

CubeSats are deployed from the ISS using the JEM Small Satellite Orbital Deployer (J-SSOD). The JAXA website lists the specifications set on deployment and notes that it is configured to avoid ISS ...
Matthew R.'s user avatar
7 votes

Orbital insertion accuracy for SpaceX payloads

The Falcon User manual provides some information: 4.5. Mission Accuracy Data As a liquid propellant vehicle with restart capability, Falcon 9 provides the flexibility required for payload insertion ...
Bob Jacobsen's user avatar
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7 votes
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Why do rockets coast before secondary payload deployment?

There are a number of reasons why this might be the case. There are two main things that a rocket has to do. The first is to get them to the right orbit, and the second is to make sure the payloads ...
PearsonArtPhoto's user avatar
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7 votes

How do cubesat owners first find out their cubesat's initial trajectory? How do they point antennas at it before official TLEs start to appear?

A cubesat without a propulsion system deployed from the second stage of the rocket using weak mechanical forces only just follows the trajectory of the second stage. Differences between the ...
Uwe's user avatar
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7 votes

What is the significance of a heat flux value of 1135 W/m^2 when jettisoning the payload fairing?

It appears that the original value was 0.1 BTU/ft2-sec, which you can see listed in some documents, for example this is from a Boeing information sheet for a Delta II launch in September 2007: This ...
Steve Pemberton's user avatar
6 votes
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help understanding this complicated structure that will deploy HySIS

The blue boxes on upper deck are cubesat deployers by ISIS. One that can house four 3U cubesats is called 'Quadpack' https://www.isispace.nl/products/cubesat-microsatellite-deployers/ ISRO/Antrix also ...
Ohsin's user avatar
  • 1,812
6 votes

What was the outcome of the launch of ZUMA by SpaceX, to the best of the public's knowledge?

SpaceX published a message from Gwynne Shotwell explaining that the first and second stage performed nominally and they cannot comment upon the status of a classified mission. Gwynne's statement, ...
geoffc's user avatar
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6 votes
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What goes into the planning and execution of the deployment of groups of LEO satellites?

I devised the plan for the ORBCOMM Gen 2 deployment while I was the Systems Design Lead for the spacecraft. Looking back on our plans and analysis, the first step was to select a scheme that met the ...
Terrance Yee's user avatar
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6 votes
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How do cubesat owners first find out their cubesat's initial trajectory? How do they point antennas at it before official TLEs start to appear?

In my experience, there isn't currently a good solution for this, especially for amateurs, hobbyists, or small commercial operators. These groups often fly small satellites on rideshare missions. For ...
Patrick Walton's user avatar
6 votes

How do cubesat owners first find out their cubesat's initial trajectory? How do they point antennas at it before official TLEs start to appear?

I've done this before, on the latest Falcon Heavy launch. Although the satellites we were working with were a good bit larger than most cubesats. Essentially, the launch provider gives you state ...
Judd's user avatar
  • 91
5 votes
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Why would the future Nanoracks airlock be built so that it must be removed from the ISS to deploy cubesats?

This design minimalizes R&D work and number of active components. At cost of more complex procedure, the module is made very simple. There's A CBM port, a dome, and valves for venting and ...
SF.'s user avatar
  • 55k
5 votes

Are cubesats deployed with fully discharged batteries? Even those on Sherpa?

Every cubesat I've seen is completely disconnected from the rocket electrically, unlike most satellites. They typically reside inside of a pod of some kind, such as the P-POD. This means there is no ...
PearsonArtPhoto's user avatar
  • 121k
5 votes
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How many spacecraft deployed from the ISS have escaped Earth orbit? Are there plans for any in the near future?

To Answer your question: How many spacecraft deployed from the ISS have escaped Earth orbit? None Are there plans for any in the near future? No A short proof: Public Sat-Catalog here You can ...
CallMeTom's user avatar
  • 3,298
4 votes
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What are the orbital mechanical consideration behind hand-launched nanosatellites from the ISS?

If you launch nadir and retrograde, you will put the object into a lower energy orbit such that, barring ISS deboosts (they do happen, but they are rare), it will never again intersect ISS's orbit. ...
Tristan's user avatar
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4 votes
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ISRO's PSLV-C37 with 104 satellites - after 56 hours only six TLEs, which factor is greatest challenge?

From experience, I assume that Space Track is in fact tracking them all. The difficulty lies in making positive identifications of the names of all of them, which will happen soon. As the separate ...
PearsonArtPhoto's user avatar
  • 121k
4 votes

Can a blimp dead drop on Mars or Earth this way?

Regarding your recent edit: No you can't just bounce around the atmosphere to slow down with a blimp. Unlike water, there is no clear limit between space and atmosphere, which leaves you with two ...
Antzi's user avatar
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4 votes
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What can be done in future mass-cubesat deploys to make them "less irksome" to orbital space debris experts?

The key consideration in Kelso's comments is that many of these satellites end up DoA, so you cannot rely on the satellite helping you in any way. Thus we are left with the need for passive methods ...
Carlos N's user avatar
  • 4,444
4 votes
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What is this "space ring"? Is it SHERPA or something new, or just "art"?

Both spacecraft appear to be utilizing an ESPA ring, which stands for EELV Secondary Payload Adapter. ESPA class missions "hitchhike" on the interstage of a larger launch. This is useful when e.g. a ...
Bear's user avatar
  • 1,565
4 votes
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How will Sherpa and Formosat-5 be configured as payload and launched?

Edit: Plans for the launch were changed, and the Formosat-5 launch didn't have any secondary payloads. A Spaceflight Incorporated rideshare payload, consisting of a SHERPA adaptor with up to ninety ...
Hobbes's user avatar
  • 128k
4 votes

Can a blimp dead drop on Mars or Earth this way?

Yes, at least in theory, but in practice there is very little atmosphere on Mars, so your blimp will have to be huge, or the payload very small.
ventsyv's user avatar
  • 1,506
4 votes

Why would the future Nanoracks airlock be built so that it must be removed from the ISS to deploy cubesats?

Above all else, that design choice is purely for the sake of simplicity. It uses the existing Common Berthing Mechanism attach hardware and seals to interface with ISS, which eliminates the need to ...
Tristan's user avatar
  • 17.3k
4 votes
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What is the final conclusion about 'object M'? What happened?

The Joint Space Operations Center or JSpOC: ...is the organization responsible for performing all of the orbit determination activity necessary to maintain the US space catalogue. During announced ...
uhoh's user avatar
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