It was hard to miss this week’s test launch of the SpaceX Falcon Heavy. The Tuesday launch certainly received more attention than any space-related story since the Space Shuttle was retired in 2011. And to be honest, this unmanned test launch garnered a lot more eyeballs than many manned launches in the past.
So … why? What was the big deal about a rocket that is, at its most basic level, just three of the boosters Space X has already been launching for years strapped side by side?
The power
Sure, it lifts more, and that’s nice for several reasons. The previous “most powerful operating rocket” was the Launch Alliance Delta IV. Capable of taking 29 metric tons to orbit, the Delta IV has been a workhorse, especially when it comes to it’s primary mission — launching US military reconnaissance satellites. At least eleven of these eyes-in-the-sky have gone up on Delta IVs. The Delta IV has been around since 2002, and has flown 36 times, but only 9 of those flights have been of the “heavy” configuration. Most have been of the Delta IV Medium, which is capable of taking between 11 and 15 tons to orbit.
The Medium and Medium+ configurations of the Delta IV actually have less capacity than SpaceX’s Falcon 9, which can loft 22 tons. In fact, by most measures, the Falcon 9 itself is a heavy rocket — in the same range as the biggest machines available from other sources.
The Delta IV uses the RS-68 engine, which is important in that it was the first new rocket engine created in the United States after the design of the Space Shuttle main engine, which was designed thirty years earlier. Unfortunately, while the RS-68 was designed to be cheaper to build than the Shuttle engine, getting there meant some significant losses in efficiency. Still, the 8’ throat of the RS-68 puts out 700,000 pounds of thrust. Which is a bunch. And a Delta IV Heavy carries three of them.
But as nice as that Delta IV is, and it’s an impressive machine, it’s a whole different animal from either the Falcon 9 or the Falcon Heavy.
Instead of that big RS-68 engine, a Falcon 9 uses much smaller SpaceX-designed Merlin engines. Not surprisingly, it uses nine of them. The first version of that Merlin engine produced 76,000 pounds of thrust. The next 85,000. The one in use on Falcon 9 now generates 155,000 pounds of thrust. Multiply by nine, and the standard Falcon 9 gets 1,200,000 pounds of thrust.
The Delta IV’s engine has a thrust to weight of 45 to 1. The Falcon 9’s engines carry a 180 to 1 thrust to weight ratio — a four-fold improvement. But when it came to trying to put up a rocket on 27 of those Merlin engines, there were a lot of very smart people with a lot of very severe doubts. In part that’s because this isn’t the first time someone tried to use a number of smaller engines to launch a big rocket.
The Soviet counterpart to the Saturn V was a rocket called the N1. Where the base of the Saturn V carried five immense Rocketdyne F-1 engines, the N1 was designed to carry 30 much, much smaller engines. The Soviets built nine N1 rockets and attempted flights four times. All ended in failures that ranged from an explosion on the pad to a failure 40 kilometers into the flight. In part as a response to Soviet issues with the N1, the idea of clustering many smaller engines got a bad reputation, with assumptions that attempting to feed and balance all those separate mouths would be overwhelming.
But … nope. The more advanced control systems that have made it possible for SpaceX to safely land their Falcon 9s tail first (I believe I’m contractually obligated to say “As God and Robert Heinlein intended”) proved more than up to the task of controlling 27 engines. It doesn’t just validate the Falcon Heavy design, it validates the idea of the Falcon Heavy design … and that’s a big deal.
The Price
If you’re in the market to loft a large satellite, you can buy your way to space on a Delta IV — for about $160 million, which is about $2,500 per pound to low Earth orbit. If your launch needs are a bit smaller, you can use the even more time-tested Atlas V, which will carry 20 tons to orbit for $109 million, at about $2,400 per pound. If it’s a bit smaller still, you can travel to Tanegashima Space Center for a launch on a Mitsubish H-IIB which cost around $3,200 per pound to orbit. Or visit French Guiana to buy an Ariane 5 for $3,700 per pound.
Or … you can get 22 tons to orbit on a Falcon 9 for $62 million, which works out to around $1,200 a pound. And finally, you can hitch a lift on a Falcon Heavy for $90 million, where the more than doubled payload puts the price to orbit at $560 per pound. Sound better? That’s why SpaceX is now manufacturing more Falcon 9s a year than the number of Delta IVs that have ever been made. And every year they’re building more, building them faster, and making them cheaper.
A big part of that cost savings comes because SpaceX has been spectacularly successful at recovering their rockets. While the central core of the Falcon Heavy test flight might have fallen into the sea, the two side boosters made an absolutely amazing side by side return to Kennedy. Even better, both those boosters had already flown on their own as Falcon 9s. A lot of scribbling has gone into figuring out just how much savings that represents, but the consensus seems to be that it saves SpaceX about $25 million per launch when it can reuse an existing vehicle. In fact, the actual cost per launch for SpaceX may already be well under what they’re charging and still going down.
The potential
There are two things that the flight earlier this week represented. First, there’s the potential of the Falcon Heavy itself. With a capacity of 64 tons — assuming you can find a way to shove all that mass into the 5 meter-wide 13 meter-high shroud — the Falcon Heavy can loft items that were simply too heavy for any existing lifter. Better still, it could revolutionize the space beyond Earth orbit. The extra power of the Heavy could allow probes to be sent on direct flights to Jupiter, Saturn and beyond without executing long, complex fly-bys of other planets to pick up speed. The Falcon Heavy will simply get things there faster, or get bigger things there just as fast. It’s what we need for the next generation of probes that could include things like automated subs for Titan’s methane lakes and drilling systems to pierce the skin of icy moons.
And maybe the biggest result of the Falcon Heavy’s successful test, is that it’s already on the road to being obsolete. SpaceX has decided to increase the pace on delivering its next vehicle — the BFR. It stands for Big … something ... Rocket. Let’s say Big Falcon Rocket. It’s the machine that SpaceX hopes to ride to Mars, and now that the Falcon Heavy has proved out their control systems, they’re moving ahead on the design, with hopes for static tests by 2019. Some of the things they were going to do with the Falcon Heavy are now being moved to the BFR.
The BFR is … a BFR. It will be as tall as a Saturn V, with far more thrust. It uses 31 engine, but they’re not the same as those on the Falcon 9 or Falcon Heavy. They’re new Raptor engines, each of them designed for 380,000 pounds of thrust. It should be capable of delivering 150 tons to orbit — or dozens of passengers to Mars.
Don’t think of the test flight of the Falcon Heavy as an end. It’s a beginning. The sign that after what seemed like a bit of a dark age, we’re in the midst of a Rocket Renaissance, one whose effects we can’t begin to predict. And SpaceX is just one of the players vying to be the leaders in this new age.
Now, let’s go read science!
If you want to see some images of the SpaceX machines, NASA’s upcoming Space Launch System, and Blue Origin’s New Glenn, here’s a nice thread.
Take a drink. Maybe two. But three … eh, maybe not.
A number of studies have previously indicated that a little alcohol now and then, say a glass of wine after dinner, may have beneficial effects. A lot of effort has gone into trying to sort out some magical chemical responsible for this effect, but a number of studies have indicated that the healthy ingredient is … the alcohol.
A group from the University of Rochester looked in particular at how alcohol plays with the glymphatic system. It’s not one of those terms you hear a lot, but the glymphatic system is the waste removal system for your central nervous system — basically how the cerebral spinal fluid gets cleaned. Of all the places where alcohol you might put alcohol, the fluid in which your brain is pickled might seem like the worst. And in fact, that’s what you find …
Acute and chronic exposure to 1.5 g/kg (binge level) ethanol dramatically suppressed glymphatic function in awake mice.
That amount of alcohol is basically a “Freshman pledge level” dose. And the resulting de-watering of the fluid is a very, very bad thing. But even when it comes to the brain, the amount of bug juice really matters.
Surprisingly, glymphatic function increased in mice treated with 0.5 g/kg (low dose) ethanol following acute exposure, as well as after one month of chronic exposure. … These observations suggest that ethanol has a J-shaped effect on the glymphatic system whereby low doses of ethanol increase glymphatic function. Conversely, chronic 1.5 g/kg ethanol intake induced reactive gliosis and perturbed glymphatic function, which possibly may contribute to the higher risk of dementia observed in heavy drinkers.
Not only does this seem to indicate that a small amount of alcohol might be a good thing, it also hints that “the hair of the dog” may have some truth behind it after all. So long as it’s a very small pinch of hair.
Does Asparagus help cancer to spread?
Asparagine is an amino acid. It’s necessary for the formation of many proteins. In 1806, a pair of French chemists isolated this amino acid from the juice of asparagus. Which is why it has that name. That little fact has turned a paper by a diverse international group into some pretty scary headlines. Like the one above. Or this one in USA Today — “Could cutting asparagus from your diet stop the spread of cancer?”
As you might expect, the truth is a bit more complicated.
Here we show that asparagine bioavailability strongly influences metastatic potential. Limiting asparagine by knockdown of asparagine synthetase, treatment with L-asparaginase, or dietary asparagine restriction reduces metastasis without affecting growth of the primary tumour, whereas increased dietary asparagine or enforced asparagine synthetase expression promotes metastatic progression.
That’s a very big deal. It suggests that the amount of asparagine available is directly related to the ability of cancer to metastasize and spread to other organs and tissues. But, if you’re heading for the kitchen to clean out your fridge, hang on a sec. First, asparagine is also found in dairy, and soy, and nuts, and potatoes, and beef, and seafood and … lots of places. Second, this is a mouse-model study, and while on something like this you might expect similar results in humans, that’s far from a sure bet. Finally, this study appears to have looked at one type of cancer — triple-negative breast cancer. How it might affect other cancers is unknown.
The study does seem to suggest that a diet that restricts asparagine might be part of a course of treatment to keep cancer from spreading — though it seems to have little effect on the growth of a primary tumor.
Altering asparagine availability in vitro strongly influences invasive potential, which is correlated with an effect on proteins that promote the epithelial-to-mesenchymal transition. This provides at least one potential mechanism for how the bioavailability of a single amino acid could regulate metastatic progression.
If you really feel compelled to change your diet, most fruits and vegetables are low in asparagine. And eating a lot of fruits and veggies is probably good for you for any number of reasons. But there is no evidence, zero, that asparagus causes cancer, and no evidence that removing it from your diet will keep you from developing cancer.
Better wood for building bigger structures.
Wood is a great building material. Plus it has some terrific benefits — you don’t have to mine it, it’s a renewable resource, and instead of creating more pollution in its creation, wood actually traps and holds vast amounts of carbon. But when it comes to creating a modern skyscraper or bridge, wood isn’t exactly the first thing that comes to mind.
So … what if you could make it stronger? Denser? (dah dah DAH dah) Better than before?
Here we report a simple and effective strategy to transform bulk natural wood directly into a high-performance structural material with a more than tenfold increase in strength, toughness and ballistic resistance and with greater dimensional stability. Our two-step process involves the partial removal of lignin and hemicellulose from the natural wood via a boiling process in an aqueous mixture of NaOH and Na2SO3 followed by hot-pressing, leading to the total collapse of cell walls and the complete densification of the natural wood with highly aligned cellulose nanofibres. This strategy is shown to be universally effective for various species of wood. Our processed wood has a specific strength higher than that of most structural metals and alloys, making it a low-cost, high-performance, lightweight alternative.
That’s just … cool.
The material is squeezed at about 50 atmospheres after the cell walls are broken down by that alternating lye and acid bath. The resulting material is about five times thinner — and five times denser — than the original wood. A thin sheet of this “super wood,” developed by engineers at the University of Maryland, even stops a bullet, meaning that houses built from the material would be much safer when it comes to accidental shootings.
Their expectation is that the material they produce could be stronger than most steel alloys, and comparable in strength to commercial carbon fiber at a fraction of the cost. If they’re correct in their estimates of what it will take to scale this to production, and the material that they’ll get as a result, this could be very exciting. Other dense-wood products have been made, but they’ve been both more expensive and less durable than what the numbers here suggest. I’m ready to wear out some saws on this stuff.
Another day, another big battery advance.
While I’m more than willing to believe in super wood, at this point I’m reluctant to believe that any reported advance in battery technology is going to reach the market. Again and again researchers have come up with better anodes, better cathodes, faster charger, higher energy density … only to stumble in bringing it to market. So even though the group behind this US and China team includes some big names in the field … I’ll believe it when it’s in my flashlight.
Rechargeable lithium metal battery (RLMB) is the holy grail of high-energy-density batteries.
Yes. They got that much right. Except that finding electrolytes that work with RLMB, and don’t break down after a few recharge cycles, or destoy the cathode, has turned out to be a challenge.
In this work, a class of full-fluoride (FF) electrolyte is invented for 5-V RLMB which not only has good compatibility with cathode and a wide stability window but also possesses the capability to make LMA more stable and reversible.
The team here indicates that they’ve come up with a fluorine salt in a fluoridated solvent that can be coupled with a lithium metal cathode for at battery that’s good for at least 130 cycles under commercial loads. That’s significant, but it’s a long way from “done.” And, as with so many battery solutions, it’s not clear that the chemistry here is easily manufactured, safe in the consumer space, and readily recycled.
It’s not just the heat, it’s the humidity.
If you’ve noticed that in some years a warm stretch quickly erases any evidence that your yard had been covered in snow, while in other years it seems that similar temperatures are shrugged off by the white stuff, it could be because there’s another factor involved than just the number on the thermometer.
Using long-term records from across the western United States, we demonstrate that atmospheric humidity is a major control on how seasonal snow responds to warming temperatures. Specifically, we observe an increase in the frequency and magnitude of episodic winter melt events under higher humidity that may alter the timing of water availability.
While this study looked at seasonal snows, In recent years, several large areas of ice and snow have melted with unexpected rapidity. It’s happened in both Antarctica and in Greenland. These breakups of ice shelf and large losses of snow on land don’t seem to fit the models. And maybe that’s because the sultriness of the air wasn’t in the numbers.
Management approaches to address these changes in snowmelt water resources from continued warming will require improved estimation of variable and changing atmospheric humidity.
Tumbling along with the tumbling people weeds.
When most people think of the term “weed,” it generally means something growing in a place they don’t want. A sunflower may be a wonder in the middle of the garden, but less welcome on the front lawn — and nodding thistle probably gets a big frown in either location. That’s pretty much the biological meaning of the term weed as well — a species in the wrong place. Where the meaning of the word “wrong” can have a lot of different causes.
Some Kent State University researchers have an idea that our hominid ancestors were weeds, in the sense that the traits they had picked up, including two-legged walking and smaller canine teeth that were likely tied to social changes, made it more possible for them to invade areas and ecological niches that previously “belonged” to other species. As a modern example, they looked at some macaques that have also succeeded in become relatively widespread across multiple environments.
When primate “weed species,” such as some macaques, are examined for those key behavioral features most responsible for their unusual great demographic success, an irregular but robust elevation of female survivorship emerges as key. It is likely that a similar adaptation characterized earliest hominids such as Australopithecus.
Two legged walking? Yeah, that’s cool. But keeping adult females alive longer seems to be the signifier of a the “weed” that’s going to last vs the ones that are going to be pulled by selection.
Honestly, the use of “weed” here as a near synonym for success seems like a stretch. But the other ideas in the piece are intriguing.
The ear—eye connection.
When you read enough scientific articles, you really appreciate it when you run into a title like this: “The eardrums move when the eyes move.” And … that’s also what the article delivers.
These observations suggest that a vision-related process modulates the first stage of hearing. In particular, these eye movement-related eardrum oscillations may help the brain connect sights and sounds despite changes in the spatial relationship between the eyes and the ears.
In short, careful studies showed that when you move your eyes, the eardrums get a wiggle. And it happens even if there is no actual sound stimulus. But when there is a sound, these eye-ear connections may be helpful in centering in on the source. And … done.
Don’t blame the rats for the Black Death. Blame those lousey humans.
Not lousy, but lousey. As in covered in lice.
Here, we show that human ectoparasites, like body lice and human fleas, might be more likely than rats to have caused the rapidly developing epidemics in pre-Industrial Europe. Such an alternative transmission route explains many of the notable epidemiological differences between historical and modern plague epidemics.
Trying to in down the factors that were responsible for the spread of the plague is a very old game, and the number of theories about it is roughly equal to the number of articles. But I like this one, because it both relieves the burden of guilt on our friend, the pizza-consuming rat, and puts it on people who don’t take a shower. Best of all, it suggests that there’s little chance of the kind of widespread outbreak seen in the past—though it’s far from an all-clear signal. And while the math works nicely, there is one little issue.
However, the transmission from body lice and human fleas to humans has not yet been documented, and thus the importance of human ectoparasite transmission in current and historic settings remains an open question. Our theoretical analysis demonstrates that human ectoparasites may indeed play such a role.
A marching, marbled army of crayfish clones.
In the lake behind my house, there are crayfish. They appear to be mostly saddleback crayfish — Orconectes medius. We have a lot of variety here. In fact, this could be among the most diverse area for crayfish on the planet (I know, now I’ll have to beat off the tourists with sticks).
But based on a widely reported article, I may need to take another look around the lake, and make sure the locals are not being displaced by an invading army of clones.
Freshwater crayfish are important keystone species that play critical roles in the maintenance of their ecosystems. Taxonomically, they belong to the order of decapod crustaceans, which includes crabs, lobsters, prawns and shrimps. Surprisingly, however, complete genome sequences from these ecologically and economically important groups remain to be established. …
The marbled crayfish Procambarus virginalis is a freshwater crayfish species that holds a unique position among decapod crustaceans due to its parthenogenetic mode of reproduction. Marbled crayfish are descendants of the sexually reproducing slough crayfish Procambarus fallax and reproduce by apomictic parthenogenesis. We have previously suggested that marbled crayfish originated through an evolutionarily very recent macromutation in P. fallax, consistent with the first known appearance of marbled crayfish in the German aquarium trade in 1995.
It’s likely that the marbled crayfish was already going at it in the wild well before that German pet shop operator noticed that his tanks were filling up with identical crayfish. And they’ve done a fine job of displacing other species in a lot of areas of the United State and Europe. They’re now happily colonizing Madagascar. Apparently parthenogenesis is a pretty useful edge in a freshwater decapod.
But this would be a great time to open up a Cajun restaurant in Antananarivo. And weirdly enough, you can still order these things for your aquarium in a lot of places in the US.
Don’t do that.