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1
All proceeding to plan. Prop loading.
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I see you're calling the Persona by their other alleged name Kvarts, but I thought it had never been confirmed that was their official name, even Anatoly Zak states it is only a reported name for them. So why not use Persona which is their more commonly accepted name.

Because I understood that the Kvarts name had been confirmed.   And please don't blame me because the Russians have so many different designators for each satellite series! ;)   Twenty years ago I suggested that the Russians were trying to "confuse us to death" with all of the different names.
3
Two Garpun military data-relay/communications satellites have been launched, a follow-on to the Potok series of satellites: Cosmos 2473 and Cosmos 2513.

After launch Cosmos 2473 took up station over the standard Potok longitude of 80 deg E and when Cosmos 2513 was launched in December 2015 it was alocated alongside Cosmos 2473.

Cosmos 2473 was manoeuvred off-station during May 18-19 2016 and was relocated over 346.5 deg E on June 30.   Cosmos 2513 remains located over 80 deg E.

Thus, the two Garpun satellites are now using the two locations which were used throughout the "first generation" Potok programme.
4
It looks as if this year will be the first time since 1961 - when the Soviet photoreconnaissance programme began launches - that we have no launches in the calendar year of either a dedicated photoreconnaissance satellite (which I include the Bars-M series) or the related remote sensing satellite series.

Of course, the Russians have two Kvarts satellites, two Bars-M satellites and 2.5 Resurs-P satellites (allowing for the problems with the third satellite!) operating at present.

I see you're calling the Persona by their other alleged name Kvarts, but I thought it had never been confirmed that was their official name, even Anatoly Zak states it is only a reported name for them. So why not use Persona which is their more commonly accepted name.
5
Test videos links showing results and how the drive functions.






6
Not to break up discussion about thrust ratings, but I saw something in the full launch-to-landing telephotography video that I wanted to point out, in case anyone missed it.  Starting at 6:44, and ending at 6:47 (you might want to slow the video down to get a good look), a ring of 8 shock trails form between the engines and over legs, coinciding with the booster going transonic.

At first I thought this was exhaust from engine startup, especially given that it ends almost exactly as the engine starts.  However, it seems too uniform and too far up the booster to be coming from the center engine, the only one that lights during this burn.  Furthermore, similar effects form around the grid fins, and engine ignition changes the environment around the base of the rocket anyways, so it makes sense that it would end such formations.

I love formations like these, and this is a really interesting one - the incoming airflow being squeezed between the eight outer engines produces a pattern that you probably won't find anywhere else!
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Space Science Coverage / Re: Boyajians Star Updates And Discussion
« Last post by Star One on Today at 06:01 PM »
Quote
Dip update 62/n
August 19, 2017
[Orig: Aug 19, 2017]
 
Hi everyone,
 
Two days of normal brightness at LCO.
 
Wishing all of you clear skies for the eclipse!   
 
~Tabby

http://www.wherestheflux.com/single-post/2017/08/19/Dip-update-62n
8
I miss the exact launch time, serial numbers and satellite launch weight.
22:06:59.975 according to russianspaceweb.com
http://www.russianspaceweb.com/blagovest.html
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Advanced Concepts / Re: nuclear generated rocket fuel
« Last post by ZachF on Today at 05:58 PM »

1.They make me do the math, but you can have your bald assertion.

2.So RP-1 is $2.50 a pound which means it is $16.87 a gallon. This is about 4 times the price of kerosene in the USA at retail.

3.And I wouldn't be surprised if you could make synthetic fuel and sell it now at that half price using coal and water.


1.  It is intuitively obvious that it would be more expensive.  There is an process that makes cheap propellant.  Building a plant that use nuclear power is to going add cost to the product.  I would be willing to bet that it would be more than 10 times.

2.  The cost compared to the domestic product is meaningless.  It has no bearing on the matter.

3. Really?. Synthetic is many more times the cost.   Kerosene is cheap

1. I said use existing powerplants.

2. I gave the cost of retail kerosene as a worst case. I couldn't easily find a whoilesale cost of kerosene.  The retail cost of kerosene is certainly higher than the wholesale cost.

3. while you qouted an outrageous price for a specific synthetic fuel, the actual cost of creating synthetic fuel is about 30% more than digging it up.  Of course, that was a few years back when oil was much more expensive. But the price of coal has fallen also. This is what a synthetic fuels engineer told me.
Ignoring economics for the moment, synthetic fuel production usually requires temperatures of 750 to 850 degrees C.  The peak temperatures of pressurized water in a nuclear reactor is around 580 degrees C.  It's not hot enough by a long shot even if you could tap into the water coming right out of the core.  The temperature drops at every step after that.

The next issue is that regulators would never allow large volumes of combustible liquids anywhere near a nuclear reactor even if they did run hot enough.  This idea doesn't fly for a number of reasons.

I think it's even less than that.. IIRC modern BWR reactors operate at under 300C and PWRs a little over 300C. Pushing the temperatures higher than that runs into problems with the fuel cladding.

You could probably make a molten-salt reactor work for those temperatures, but those need a lot of development. They ultimately have never gone past the experimental/powerpoint phase.
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Come now Jim...they weren't points. More like honest questions.
But I am very interested in this flying cake of yours. :)
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