News: 1584549913

the application of paint to darken reflectivity had "helped somewhat with the issue of the objects' brightness"

Are all the satellites getting the new paint job? Some of the earlier articles hinted that only a limited number were given the treatment as a test program? (Would be a good PR strategy: "oh, the satellites are still too bright, well, yes, you saw a non-treated one, later ones will be better")

"Are all the satellites getting the new paint job?"

I shouldn't think so, who would want to be the one up there with a tin of paint and a brush? I'm crap enough at painting without having to catch the bloody thing I want to paint first.

"I shouldn't think so, who would want to be the one up there with a tin of paint and a brush? I'm crap enough at painting without having to catch the bloody thing I want to paint first."

Cue intro to Red Dwarf.

Sure, but does not show value of having so-called recoverable rockets.

Too bad, that.

The successful launch of the satellites showed the value of "recoverable" rockets. This was its fifth and last time it sent a payload to orbit: four more recoveries than anyone else has managed.

"four more recoveries than anyone else has..." risked, because they knew it wouldn't be viable to do too many and there were too many variables and too much money at stake to just let the things blow up because someone didn't service them properly between.

Huh? What?

You do realise that the mission was a success right? The payload reached orbit.

For any other current rocket outfit this missions outcome would rate as 100% successful.

Did the loss of an engine require a longer burn resulting in not enough fuel for a controlled landing or are specific engines required to land?

I don't think they have said exactly but I believe that there are some differences between the engines so specific ones are required. e.g. not all can relight and possibly not all can throttle down low enough. I think the centre one is pretty much essential at landing time.

If you watched the re-entry burn there was a lot more swinging around than normal which suggests that the problem engine was either one of those 3 or had perhaps been damaged by the explosion(*).

(*) - If you watch a few seconds before the main engines shut down it certainly looks like something exploded - it was a bit fireball-ish...

Yeah, this is also a 5th flown rocket. So overall, improvements being made and progress for the company.

It can all still go wrong. As the recent changes in the world show. Know one knows what tomorrow will bring, and our priorities are important. But as a Rocket Company, Space X do quite well.

It was a SpaceX payload on a SpaceX rocket, so they didn't seem too bothered by the "risk". The satellites reached orbit.

SpaceX do not appear to be short of customers willing to take this "risk" of launching on a reused booster.

Unfortunately, SpaceX are not the only entity at risk if they have failures in launch, insertion or orbit (or de-orbit).

That's what launch insurance is for, because historically there's an element of risk with every launch.

However, a failed landing only makes a difference to SpaceX's bottom line (unless it lands on someone's head of course).

As it stands, 86 launches, with 84 successful payload insertions for the Falcon 9 (one lost in flight, one on the ground before launch) is a 97.7% success rate, which is pretty good for an orbital rocket. Antares is down around 80%, whereas Delta 2 is around 98%, Ariane 5 is about 95%.

So all in all, if you had a satellite to launch, you could feel reasonably confident putting it on a Falcon 9 that it would reach orbit, and by all accounts, their prices are some of the cheapest.

I presume the first stage has a contingency "Yee-Haa!" klaxon to announce an imminent splashdown?

[...] more than five flights will be needed per booster to make the figures work.

Anyone know which figures are being referred to here? Is this saying that SpaceX can't make a profit if they only reuse their boosters five times? I was under the impression that they make a healthy profit per launch already, with the levels of reuse already achieved. Of course that only gets better if they can do a hundred launches per booster.

It all depends on how they account for the R&D costs. Even without that it's hard to determine. Whilst they do claim to be running at a modest profit I believe this is somewhat down to "accounting" practice. The first cash comes in when a launch contract is signed. SpaceX then spends money making it happen and gets more money from the customer. It's probable that after the initial signing fee they get less additional money from the customer than their costs. Their current modest profit is coming from an expanding order book, and all will be good if they keep their future costs down ..... by getting lots of reuse out of the boosters.

So it's either a Ponzi scheme or false accounting (recognising revenue and associated profit before providing the contracted goods/service) or both?

Also... Falcon 9 (and Falcon Heavy) are only interim vehicles; Starship aka BFR is the direction SpaceX is heading, as you'd know from the video: they want 3 launches [i]per day[/i] While a Falcon 9 can put 60 Starlink satellites in orbit, the Starship is expected to carry about 400...

As to the economics of 4, 5 or 100 launches: I believe this is a reference to the economics of Starlink, not regular commercial launches. But even then, the economics are soon to shift: they have 300 "v1" satellites in order, with another 58 "production ready".... and 420 is the number they need to start providing service aka generating income, with 780 to provide "moderate" coverage.

Of course, one of their target markets is "aircraft in flight", and that depends on the airlines surviving the virus.

According to Musk roughly the booster costs $17m and the fairings about $5m in total.

Obviously a bunch of that will be spent refurbing the stage and the fairings. But to date SX's reuse would have put up to $73m into SX's bottom line so far.

OTOH since Musk said they spent about $1Bn to develop booster recovery that's about 56 flights to recover those costs.

Pretty impressive.

What is the UFO that's visible flying up past the descending first stage at 06:39? Blink and you miss it...

Elsewhere, probably in some tweets or PR materials, it's been said that this is some type of cover that goes in/around/over the engines after MECO to help protect them from atmospheric forces during re-entry.

They never mention it during the live streams, and it can be hard to find any credible information on it. It's a regular event seen during main booster reentry, and due to the speed of the booster + relative speed of the object it pretty much has to come from the booster itself. Others may have just guesstimated what it is based on that, that may be where I heard it from too. Must be some proprietary technology for Space X to be so hush about it. UFO is correct here!

Not a UFO. A IFO. Identified flying object. It was ice off the rocket.

Starlink may not be helpful for astronomers in intermediate latitudes.

Paper by McDowell on the effect of Starlink on astronomy work is available here:-

https://arxiv.org/abs/2003.07446

Synopsis:-

[McDowell] discusses the current low Earth orbit artificial satellite population and show that the proposed `megaconstellation' of circa 12,000 Starlink internet satellites would dominate the lower part of Earth orbit, below 600 km, with a latitude-dependent areal number density of between 0.005 and 0.01 objects per square degree at airmass < 2. Such large, low altitude satellites appear visually bright to ground observers, and the initial Starlinks are naked eye objects. I model the expected number of illuminated satellites as a function of latitude, time of year, and time of night and summarize the range of possible consequences for ground-based astronomy. In winter at lower latitudes typical of major observatories, the satellites will not be illuminated for six hours in the middle of the night. However, at low elevations near twilight at intermediate latitudes (45-55 deg, e.g. much of Europe) hundreds of satellites may be visible at once to naked-eye observers at dark sites.

Disclaimer:-

I am not an author of the paper, am not related to McDowell or work with him etc. However I do engage in amateur astronomy when the clouds permit. Starlink stands to be a fecking pest if you are not interested in Starlink itself.

Watch out for killer asteroids! Oh, we can't anymore... but we do have Facefsck

This was the second Starlink launch to use a different launch profile. https://spaceflightnow.com/2020/02/17/timeline-for-falcon-9-launch-of-starlink-satellites-2/ . I'm sure I read somewhere that this makes booster recovery harder.