Here at UT, we’ve had several stories that describe the concept of a space elevator. They are designed to make it easier to get objects off Earth and into space. That, so far, has proven technically or economically infeasible, as no material is strong enough to support the structure passively, and it’s too energy-intensive to support it actively. However, it could be more viable on other worlds, such as the Moon. But what about worlds farther afield? A student team from the University of Colorado at Colorado Springs looked at the use case of a space elevator on Ceres and found that it could be done with existing technology.
Before we discuss why anyone would want to put a space elevator on Ceres, let’s first examine the technologies that would make it possible. Every space elevator design has three different components: an anchor, a tether, and a counterweight. Each would require its own technologies.
The anchor is simple enough; it’s how the system interfaces with Ceres. The surface of Ceres is primarily made of clay, which is relatively good for anchoring technologies. Luckily, the force the anchor needs to withstand is only around 300N, which is much lower than the force on Earth, given Ceres’ small mass. There have already been asteroid anchoring technologies for other missions that can provide up to 500N of force resistance, so an anchor on Ceres should prove no real challenge.
Fraser describes the general idea of a space elevator.The tether is where the technology falls short on Earth – no material known to science can withstand the forces exerted on the tether of a passively controlled space elevator when it is tied to Earth. However, the closest we can come, something space elevator enthusiasts mention as almost a holy grail, is carbon nanotubes. In the analysis for the space elevator on Ceres, they once again came out ahead. However, the limitation of actually physically creating a long tether will still plague any space elevator design on Ceres.
The counterweight is much simpler, as it can be just a big, dumb mass. However, its mass is proportional to the necessary length of cable—the heavier the mass, the shorter the cable. So, the tradeoff between having a heavier counterweight and a shorter cable is another design consideration when considering these systems.
Calculations from the team show that, with only a little more technological development, all three main systems could be ready for installation on Ceres itself. But what advantages does it have? It could be helpful as a launching point for accessing other asteroids in the asteroid belt. Ceres also has water relatively near the surface, which is helpful for all kinds of human exploration, either as rocket fuel or biological systems. It’s also well placed to quickly get things back to Earth using Jupiter as a gravity assist.
Isaac Arthur goes into a deeper description of space elevators and their advantages.But before it can provide any of those advantages, someone is going to have to pay for it. Estimates of the overall cost of the system total about $5.2 billion — not too far out of the range of larger-scale space exploration projects. But more than most countries are likely willing to pony up for a grand infrastructure project that hasn’t yet proven its benefit.
So, for now, any space elevator will remain in the realm of science fiction. But research like this and other ongoing technological improvements is how we will eventually push forward to that future. Whether it’s a space elevator on Ceres, on the Moon, or some other novel launch technology, someday humans will need a better way to get off Earth rather than burning dead living organisms. Hopefully, that day will come sooner rather than later.
Learn More:
Bate et al. – Analyzing the Potential of Space Elevator Technology for Sustainable Asteroid Mining
UT – What is a Space Elevator?
UT – A New Method for Making Graphene has an Awesome Application: A Space Elevator!
UT – A Japanese Company is About to Test a Tiny Space Elevator… in Space
Lead Image:
Artistic view of a possible space elevator.
Credit: NASA
The post Using A Space Elevator To Get Resources Off the Queen of the Asteroid Belt appeared first on Universe Today.
Exoplanets have been discovered with a wide range of environmental conditions. WASP-76b is one of the most extreme with a dayside temperature of over 2,000 degrees. A team of researchers have found that it’s even more bizarre than first thought! It’s tidally locked to its host star so intense winds encircle the planet. They contain high quantities of iron atoms that stream from the lower to upper layers around the atmosphere.
Exoplanets exist outside of our Solar System and orbit other stars. The first confirmed discovery was back in the 1990’s and since then, over 5,200 have been discovered. Many of them are gas giants like Jupiter or Saturn and others are small rocky Earth like planets, minus perhaps their habitability status. As more advanced telescopes and detection techniques are developed not only will our detection levels increase further but so will our ability to explore these alien worlds.
Artist impression of glory on exoplanet WASP-76b. Credit: ESAOne such exoplanet, WASP-76b has received quite a lot of attention of late. It is an ultra-hot gas giant that is 640 light years from us in the direction of the constellation Pisces. It was discovered back in 2013 and has an orbit that is very close to its host star, completing one orbit in just 1.8 Earth days! It’s the proximity to the star that has led to the extreme daytime temperatures of over 2,000 degrees. The intense heat is thought to vaporise iron which then condenses into liquid on the cooler night-time side and fall as iron rain!
A team of astronomers, with some from the University of Geneva, announced their findings in the journal Astronomy & Astrophysics of evidence for intense iron winds in the atmosphere of WASP-76b. Astronomers have been focussing on this planet since its discovery to try and understand the mechanisms in the atmosphere of this ultra-hot Jupiter world. It really is a fascinating world and even a rainbow was detected there last April!
The team kept their attention on the day-time side where the temperatures are far higher. They used the ESPRESSO spectrograph that was installed on the European Southern Observatory’s Very Large Telescope (yes that’s its name!) It is known for its stability and high spectral resolution so it can discern wonderfully fine levels of detail in a stellar spectrum.
The four 8.2-metre Unit Telescopes of the Very Large Telescope at the Paranal Observatory complex. ESO/VLTUsing a technique known as high resolution emission spectroscopy, the team studied the visible light spectrum. The approach relies upon the detection of emission lines in a spectrum and enables the chemical composition to be decoded. Here they detected the chemical signature of iron and found that they were moving from lower levels to the higher layers of the atmosphere.
The study of exoplanet atmospheres help us to further develop our understanding of the range of environments on these alien worlds. As a gas giant, the discoveries on WASP-76b help us learn a little more about the climates of worlds that are barraged by extreme levels of radiation from their host star.
Source : Iron winds on an ultra-hot exoplanet
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Well, it was a grueling 15¼-hour flight from Cape Town to Dulles Airport in the Virginia suburbs of Washington, D.C., and that was on top of a five-hour wait for my plane at Cape Town International Airport, resulting from an 8 p.m. departure when I had to check out of the hotel a bit after noon.
I tried to sleep on the plane, but it was largely futile. So, as usual, I watched a passel of movies, which included the first film (1972) of the movie trilogy “The Godfather” directed by Francis Ford Coppola. After watching the whole three-hour movie carefully (and for about the fifth time), my opinion is only strengthened that this is one of the best American movies ever made (my top choice, which I’ve often mentioned is “The Last Picture Show,” released a year before “The Godfather”).
I know some people don’t or can’t rank movies, but if you’re daring enough to do so, I’d be delighted to hear readers’ choices for Best American Movie. (As for best foreign films, I’d choose two Japanese ones: Kurosawa’s “Ikiru” (1952) and Ozu’s “Tokyo Story” (1953).
BTW, I had forgotten that Marlon Brando, playing Don Corleone, is not the first character to speak in the movie; rather, it’s an undertaker asking the Godfather to exact justice on the undertaker’s daughter, beaten up by a gang of sexual predators. The first sign of the Godfather is the movement of his hand at 1:30. Here are the first 6.5 minutes:
The movie won the Oscar for Best Picture, and Brando nabbed it for Best Actor, but declined the award. It won a third Oscar for Best Adapted Screenplay, shared by Coppola and author Mario Puzo.
I’m now cooling my heels at Dulles for two hours, waiting for the 2.5-hour flight to Chicago. After that it’ll be another 1.5-2 hours before I get home. It’s been a long, long flight, but less grueling than my canceled flight to South Africa, which I rebooked flying (after our flight to Cape Town to Dulles was canceled) from Dulles to Newark, then from Newark to Johannesburg, and then from Joburg to Cape Town.
I still have at least two photo-and-text posts left for South Africa, including a visit to the Kirstenbosch National Botanical Garden in southern Cape Town, perhaps the best such garden I’ve ever seen. I hae photos of many flowers, including the resplendent King Protea (Protea cynaroides), the national flower of South Africa. Here’s a preview (these flowers can be as much as a foot across):
Meanwhile, in Dobrzyn, Hili is being a typical cat:
A: Here you are!
Hili: Yes, because it’s a good place for a siesta.
Ja: Tu jesteś!
Hili: Tak, bo to dobre miejsce na siestę.
Shortly after endorsing Donald Trump for President, Robert F. Kennedy Jr. claimed he and Trump will "make America healthy again." His proposals to do that range from semi-reasonable to outright quackery.
The post RFK Jr.’s MAHA manifesto: How not to “make America healthy again” first appeared on Science-Based Medicine.