There are a class of celestial objects much heavier than our systems Jupiter but about the same size. They are not really planets just balls of dense hot gas, but they are not really stars because they lack the mass to collapse and heat their core to ignite sustained fusion. These Brown Dwarves are probably one of the most common objects in our universe but little is known about them because until recently they were essentially impossible to find. With new tools and new techniques this fascinating class of in between are coming into focus.
“Thus, gene therapy treatment of only a few nerve cells stimulated the axonal regeneration of various nerve cells in the brain and several motor tracts in the spinal cord simultaneously,” says Dietmar Fischer. “Ultimately, this enabled the previously paralyzed animals that received this treatment to start walking after two to three weeks. This came as a great surprise to us at the beginning, as it had never been shown to be possible before after full paraplegia.”Above article in MedicalXPress via Phys.org
Let’s hope this paves the way for human treatment. Not that I don’t love cyborg exoskeletons in their place, but this is far better.
The proposed Juno extended mission (EM) would take advantage of the natural northward progression of the periapsis of the spacecraft’s orbit and the consequent lowering of spacecraft altitudes over Jupiter’s high northern latitudes. The EM would run until the end of the mission, with an expected duration of approximately four years. Under the High and Medium Scenarios, propulsive maneuvers would be utilized not only to target Jupiter-crossing longitude and perijove altitude, as during the prime mission, but also to target close flybys of Ganymede, Europa, and Io. The flyby maneuvers would act to shorten the spacecraft orbital period, yielding more close passes of Jupiter within a given time interval, and increase the rate of northward movement of spacecraft perijove. Under the Low scenario for EM operation, the satellite gravity assists and close satellite flybys would not be attempted.from the Senior Review
Exciting new data from Jupiter inbound over the next 5 years. Just in time for this….
I follow Centauri Dreams closely, it is a very good source on fascinating articles about what might be called the near universe and our ability to explore it. Dealing with the outer solar system and beyond, near future realistic interstellar exploration in all its technical gore.
A recent article (A Statite ‘Slingshot’ for Catching Interstellar Objects by PAUL GILSTER on JANUARY 5, 2021) dealt with how to intercept/flyby interstellar objects (ISO) like ‘Oumuamua’ the icicleoid. This is very much in line with Arthur C. Clark’s classic (and my near all time favorite Science Fiction) Rendezvous with Rama, about the passage of a vast interstellar space ship through Sol system and a desperate dangerous mission to intercept and explore.
With current technology this appears impossible, you’d have to plan and launch a mission with a Falcon Heavy class craft in a few months to have any kind of chance. But there is a near term possible technology that makes it almost easy. The Statite is a ‘satellite’ that uses a solar sail to ‘hover’ instead of kinetic energy to orbit. Essentially this is storing energy and either the main vehicle or a cube sat sized sub satellite can be dropped straight down the gravity well to gain the velocity required to get the flyby in time. This is REALLY COOL stuff….
In the early days of space exploration it was the rocky planets, particularly Mars and Venus that held some hope of significant life. Though those with the tools of observation and analysis were pretty negative and life in the rest of the solar system looked impossible. But as our knowledge and tools expanded the icy moons quickly became of interest because as cold region natives know, ice is not a bad insulator and a couple of miles of it would protect a lake. These days it seems pretty clear that Icy Moons often have oceans, seas or lakes inside, and the heat that melts the ice from underneath (from orbital stresses and or radioactive decay) could quite conceivably support life.
The article linked discusses model based research based on data from earlier orbiters and flybys. It shows that notionally their are several mechanisms that could be feeding nutrients and energy sources into the ocean of Enceladus, at a rate suffient to support a significant biome.
There are lots of other interesting articles on space at universe today website, take a look.
So this seems crazy but in all honesty it has actually been a thing for a long time. It is mentioned in a lot of sixties/seventies SF not focused on space flight. It was seriously studied several times as a sort of replacement for parachute insertion of military force. And like most of those sorts of efforts there was a commercial concept to support the technology since the folks in the defense industry understood that military programs cannot support a robust industry on its own.
Just look at nuclear power, there was a reason that nuclear power stations evolved as the Navy came to realize they wanted nuclear ships. And there is a reason that small aircraft carriers and non nuclear submarines are anathema to certain parts of the Naval establishment. They know that if non nuclear CVs and SSs became common the industry required to support the nuclear fleet would become unaffordable.
People have already talked about the DoD buying Starships and using them as bombers / hypersonic weapons platforms. This is just turning the model above around.
Back in medieval times freighters and warships were the same thing, they just tacked on some fighting platforms and went at it with bows, crossbows, catapults, swords, etc. Even the Vikings probably started out as traders though always ready to ‘raise the black flag and slit a few throats’ if that looked like the right business strategy.
Anyway…sorry for the side commentary, it’s evening and I had a good dinner so I’m wandering a bit.
So, again anyway…if you look at it, a craft like the Starship, which has the performance as a single stage vehicle to haul 100 tons 10,000 miles in less than an hour has some attraction on its face….but in reality?
- To my mind the most value dense time sensitive cargo is people but that’s years out at the least.
- In the meantime are there cargos that are so time sensitive that something like a starship might make sense?
- Couriered documents. Maybe
- Mail. Does not seem like it.
- Medical supplies only if the ship could land almost anywhere and take off again.
- High value tech like chips? Maybe but 100 tons is overkill.
- In fact most of the above are not 100 ton class cargos and frequency and flexibility of landing seem critical.
So dead on arrival? No there are customers who might pay for a a limited 100 ton capability. I think it would need to be anywhere in the world which is more than 10,000 miles but is probably within the capability of a modified Starship with more fuel and less cargo…or maybe an extended tank Starship could do 100 tons out to 18,000 miles (my wag of anywhere in the world from anywhere in the world.)
A somewhat smaller starship could do 10 tons 18,000 miles and probably land at just about any port or airfield as long as you can supply LOx and LNG, which is not that uncommon.
Go back to the start. If you burn a couple of hundred tons of LOx/LNG what is the cost? Does it make economic sense? Is it safe, is it going to be acceptable?
- LOx/LNG are in the same $/ton range as Jet fuel, you are burning a couple of times the fuel since you have to haul up the oxidizer with you and pay for that as well so say 4x the fuel bill.
- The hull is in line with a modern airline.
- If you can do a trip a day or so with support costs in the same range as a jet, it would appear to me that for the right cargo you could make it work.
- Is it safe?
- Well not right now but once the tech is wrung out ?? I think so.
- the big difference is much higher energies than a jet.
- But…your exposure time is a fraction of that of a jet over the same range. Accidents in mid flight are rare but generally lead to complete loss. Exposure time is probably the most important difference…advantage Point to Point
- Ok so the major threat time is when you are near the ground around take off and landing, Those are shorter for the Point to Pointer.
- And to me the difference in energy involved is immaterial…dead is dead and most of the time accidents of any magnitude in those phases are not survivable.
- Accidents on the runway often have survivors but that is eliminated in the Point to Point case…up and down…no in between…
- Only time will tell, my guess is YES.
- It will be a bit like the glamor days of the early airliners I would expect point to point for certain segments to be a real elite punch card
- Especially as near earth space becomes an exotic but achievable location.
Exciting times indeed.
A composite image showing jets and radio-emitting lobes emanating from Centaurus A’s central black hole. Credit: NASA/ESO/WFI
The photo-art and the article it goes with. The article Grey is the new black hole: is Stephen Hawking right? Jan 29, 2014 by Geraint Lewis at The Conversation. It is a great piece of science writing explaining the evolution of our understanding of Black Holes and the context of Hawking’s latest pronouncements
Permian Seafloor — More than 90 percent of ocean species vanished during the Permian extinction. Credit: University of Michigan Exhibit of Natural History
Late Permian (260 million years ago) — All the world’s lands had joined into a single supercontinent, Pangea, and all the world’s sea water had formed a global ocean, Panthalassa. Credit: Ron Blakey, NAU Geology
Some 300 million years ago, at the beginning of the Permian period, all the world’s lands had joined into a single supercontinent, Pangea, and all the world’s sea water had formed a global ocean, Panthalassa.
The formation of Pangea led to higher mountains and deeper oceans. According to an equilibrium principle, a giant continent should have a thicker crust than each scattered continent, and the oceans should become deeper. This recession of water away from the land would have eliminated a lot of the biodiversity that thrives in shallow water near the coasts. This recession would have also led to changes in ocean currents and wind patterns, initiating global climate changes.
What’s more, the inland region of one giant continent would become dry and arid, leading to the disappearance of much vegetation.
But something else also went on, deep within the Earth.
When the lands joined, some tectonic plates moved under others and sunk deep into the Earth’s mantle. That cooler material then may have reached all the way to the Earth’s core layer. Evidence for that includes the reversal of Earth’s magnetic field that occurred around that time, an event called the Illawarra magnetic reversal.
The accumulation of cool material near Earth’s core then could have led to the formation of a large mantle plume (by a process called thermo-convection), other researchers had suggested. That “super-plume” would eventually reach the Earth’s surface in two separate bursts—first with an eruption in China 260 million years ago, and then with the other in Russia 251 million years ago.
By that point, all life had nearly vanished.
Read more at: http://phys.org/news/2013-11-tectonics.html#jCp
Swifts stay airborne for six months at a time: by Andy Coghlan. 08 October 2013
It’s possible young swifts don’t spend much or any time on the ground for three years.
Some theorize sleeping on the wing or shutting down half the brain. But it’s known that dolphins and suspected other large marine mammals can be awake for weeks at a time with no harm.