Comment by KirinDave | Hacker News Reader

Comment by KirinDave | Hacker News Reader

As someone who worked directly on VAFB's spacerange modernization: they also have slightly better equipment for launches than Kennedy.

VAFB's vertical wind profiler[1] is slightly more reliable, VAFB's disaster planning is easier too.

If you're not launching something supermassive that should be as close to where it was assembled, Kennedy is not your best call. That's why a lot of small and on-the-dl loads tend to go there. Also: weather is consistently more favorable in California that far south.

The less great part about moving more launches there is that the options for public viewing are way worse.

[1]: Science trivia: it's awful old school to use weather balloons to measure wind shear layers. Now they have radars so good they literally point them straight up and let the wind shear bounce radars back down. It's amazing that this works. It's so good that it can see birds!. Some operators claimed to be able to discriminate breeds, although I have no idea how they'd validate that.

Neither site is ideal, even restricting choices to the USA.

For polar orbit, obviously northern Alaska is proper. This minimizes the amount of east-west movement that must be cancelled out.

For more typical orbits, being near the equator is better. There are many choices, but Jarvis Island is probably the best. It has excellent weather and is nearly on the equator. Other good choices are Palmyra Atoll and Baker Island.

There is something to be said for altitude and dry air. Altitude is kind of obvious, yet not. Although the height is not significant relative to orbit, getting above a few miles of thick air is nice. Dry air is helpful with cryogenics; remember that ice destroyed a space shuttle. Due to the high heat inherent in solid-liquid transition of water, ice formation puts lots of heat into the cryogenics. These considerations point toward a site near Tuscon or on Hawaii's big island. The astronomers probably don't want to share either spot, but hey, they might get space telescopes in exchange.

Not Tuscon but just west of White Sands Test Range (hence the Virgin Galactic spaceport) having the advantage of White Sands' unlimited restricted airspace to keep launches clean.

Definitely to the west ... those winds are killer: https://earthobservatory.nasa.gov/NaturalHazards/view.php?id...

You launch eastwards anyway. With WSMTR to your east you get the advantage of clean air to a degree that even Canaveral can't guarantee.

They actually do have to clear all launches with White Sands, though. I mean... not that they have many launches from there (yet?)

Shipping rockets to tropical islands is brutal from a corrosion perspective, though. If I recall correctly, that was the root cause of SpaceX's failure of the first Falcon 1.

Interesting you say that. The engineers I talked to always told me that they preferred lower (sea level) launches because of disaster recovery (lower winds and lower potential contamination area) and because stats suggested lower launches gave more stability at the start of the flight when the rocket is typically most unstable.

I am _not_ rocket engineer though. This is simply what I remember experts telling me >10 years ago. :)

> The less great part about moving more launches there is that the options for public viewing are way worse.

Is this a concern for them? The article also says, "They chose Vandenberg to lighten the load off of Kennedy and allow West Coasters to experience an inter-planetary launch."

If they want to encourage public viewing, it seems odd that they schedule the launch for 4:05am…

Launch times are determined by the Earth's position around the Sun, and the overall transfer window is only a month long due to Mars' and Earth's relative positions. Unfortunately, they don't have much choice in the matter.

I'm not sure it is for anyone. I'm simply stating facts about the geography and public viewing spaces.

It's amazing if you work there though. There are these sketchy rusty bleachers you can go chill at that are distressingly close to the launch site. Everyone has to wear inner and outer ear protection, no kids allowed. Pretty epic, but only for contractors and airforce staff.

> Some operators claimed to be able to discriminate breeds

It's well known that experts can distinguish the African Swallow from the European Swallow simply by airspeed.

Plus, they can determine whether the bird is carrying a payload.

Guard: Are you suggesting that coconuts migrate? Arthur: Not at all! They could be carried.

You can actually classify mosquitoes and other insects by wing flapping. Time series is a perfect application for things like this.

How do eastward lunches work from Vandenberg?

They don’t. South (or, very rarely, west) is all you can do from there.

Aren't south launches are usually for polar orbits, how do you get from it into a Mars Transfer Orbit?

Orient your polar orbit perpendicular to the sun, burn to achieve Earth escape velocity approximately when you’re over the equator, and you’ll end up on an elliptical solar orbit in the same plane as Earth’s orbit. Burn the right amount and adjust the plane a bit and you’ll be in a Hohmann transfer to Mars.

What’s the added cost for that? I know that the Shavit launches are all retrograde despite the geography allowing for a southward launch because transfer from polar orbit to LEO isn’t cost effective for their platform.

Polar is a kind of LEO, at least if it’s low polar. The burn from LEO to Mars transfer will be about the same regardless of whether you’re coming from an equatorial orbit or a properly-aligned polar orbit, so the added delta-v cost will be the speed of Earth’s rotation at the launch point, which you don’t get to use for a polar launch.

In terms of dollars, if you’re flying on a rocket with enough excess capacity anyway (as seems to be the case here), it’s free. If you’re not, then you’ll need to cut your payload or use a bigger rocket, which would be extremely expensive.

Reply on news.ycombinator.com