Obviously this is a problem for radio astronomers. I keep hoping we’ll build the proposed Lunar Crater Telescope so we can have a truly silent view of the universe.
For multi-mode (full duplex) you would still need a power amp repeater every 500 meters, which requires a lot of power and create noise. You can’t be quiet with noise.
Yes, because there’s no way to transmit power or data anywhere without being loud af in any signal spectrum. It’s physically impossible.
Even with fiber, you need a laser to beam the signal, and a powerful amp on the moon to recieve the signal and boost it with fuck ton of high power repeaters to the other side of the moon which is also loud af
Be that as it may, it’d be minimal compared to the interference that terrestrial radio observatories have to deal with.
I guess I’m just saying that I don’t understand why you’re being so negative about the concept when it’s clearly going to be orders of magnitude better than existing antennae.
If your instance is any indication of location: there’s an eclipse visible in most Oceania and SE Asian islands in 2028. For a good chunk of Australia and NZ, it’ll be a total eclipse. For further info, check it here.
For me (South America) there’s one already in October, but it’ll suck from my region (14% coverage). And another in 2027 (~75% coverage).
The big difference is how close the sun is to solar maximum this year! The sun is at a point of peak electromagnetic activity, something that happens every 10 to 13 years, which is reflected in more chance of witnessing bursts of energy (flares and ejections) during the eclipse.
Me too, the clouds overhead parted just before totality and the corona was so dazzling and magnificent. I really hope there aren’t clouds in the way during this one.
I would love it if publications could just limit their headlines to one misleading term per story. The rocks are a ‘city’? Sure. The geysers looks like ‘spiders’? I guess. But when you start putting them together in the same headline it feels like your breaking the fourth wall or something
Yeah its hard to read as quote spiders unquote quote inca city unquote. New articles should not be doing this. geez at least put so called or something.
“Tired light” has been theorized before, and it just doesn’t hold up to most of the evidence gathered.
It’s entirely possible that there’s something there, but most data currently backs up the Lambda-CDM model of the universe. en.wikipedia.org/wiki/Lambda-CDM_model
Only time will tell if this theory pans out, but I wouldn’t put much money on it.
Discreetly insulting both Australia and Pluto in one sentence! Absolutely love this; will share it with all my Australia and Plutonian friends! If Earth gets attacked, it’s not my fault, but yours :'P
On 20 April 2016, the Sky and Telescope website reported a sustained brightening since February 2015 from magnitude 10.5 to about 9.2. A similar event was reported in 1938, followed by another outburst in 1946.[20] By June 2018, the star had dimmed slightly but still remained at an unusually high level of activity. In March or April 2023, it dimmed to magnitude 12.3.[21] A similar dimming occurred in the year before the 1945 outburst, indicating that it will likely erupt between March and September 2024.
And if I’m interpreting some of the other content correctly, it’ll come and go in one night? Maybe someone who knows more about these can confirm or correct me.. See update below.
Also …
Even when at peak magnitude of 2.5, this recurrent nova is dimmer than about 120 stars in the night sky.
Once its brightness peaks, it should be visible to the unaided eye for several days and just over a week with binoculars before it dims again, possibly for another 80 years.
Reminds me of when Betelgeuse, the orange upper star of Orion, went dim in 2020. Lots of amateur reports on its brightness, 3x per night, for a few months waiting for it to go nova. It settled down a bit before disappearing behind the sun for the season and came back just fine. It was kinda fun to monitor, but soooo many false alarms from people trying to call it first
That’s how it was for me in 2017. The path of totality went right over my house. I took the day off and strolled out to my back yard to watch it. We also smoked some meat and invited people over for a party, which was the most effort in the whole situation.
Radiation associated with Starlink satellites was detected at observing frequencies between 110 and 188 MHz, which is well below the 10.7- 12.7 GHz radio frequencies used for the downlink communication signals.
(The original article said 5M radiation, which should be around 60MHz.)
So Starlink is emitting RF in spectrum where they shouldn’t, which is avoidable, but takes effort.
My guess, and I could be wrong, is that this could be related to something other than the radio(s), such as switching power supplies finding opportunistic structures from which to radiate.
Starlink seems like a genuinely interesting and useful technology, in some ways.
But it also seems like it might not be worth having.
I’m thinking they might need to be deorbited, but I’m not confident in that yet. It sounds like it might be fixable in a new generation of Internet constellation satellites.
Idk how long the issue should be tolerated to wait for that, though. And while Starlink has a good amount of customers this kind of Internet is genuinely useful for, it’s still not a lot compared to all the other internet services.
Maybe Starlink deorbiting should come along with an expansion of the traditional communications network. But maybe it would be extremely expensive to reach Starlink’s customers with towers or cables.
Titan is a place where methane and ethane rain from the sky and have a hydrologic cycle like the kind we’ve only ever seen before with water on Earth. These organics form rivers and flow into seas, carrying sediment with them. This mission will be going to the equatorial desert to understand that sediment.
Titan, like Europa, is an icy ocean moon. Titan is even larger, though. While Europa’s ocean is measured to have about twice the liquid volume of all of the earth’s oceans combined, Titan’s ocean (which possibly has significant quantities of ammonia and organics and alcohols mixed in) has five times the liquid volume of all of the earth’s oceans combined.
Sitting atop this ocean is a thick icy crust, upon which is a surface that looks more earth-like than any other planetoid surface in our solar system. Although it looks earth-like, the chemistry is in fact fundamentally different. It is based around organic solvents instead of water as the dominant driver of weather and erosion. The water on titan is stored in the bedrock!
And the sediment on top? Well, titan’s atmosphere is 5% methane. That methane gets hit by UV light and turns into more complex organics. Titan’s atmosphere is also rich in nitrogen and carbon monoxide, which add Nitrogen and Oxygen to these complex organics. These organics sediment out and coat the surface. Around the equator, they blow into large dunes in a desert biome. Precipitation falls and erodes the tar-covered landscape. These complex organics get mixed together as sediment in the rivers and dumped into the beds of the polar lakes and seas.
Dragonfly isn’t going to the seas. Too dangerous for the first mission here. We don’t know what we’ll find, and it’s hard to communicate with earth, and there is complex weather and clouds called the “polar hood” that might interfere. Dragonfly is going to the desert, to observe the complex organics falling from the sky and gathering on the ground to be blown into dunes. These are the ingredients that will get mixed together in the seas. There is also a cool crater there that calculations suggest melted the H2O bedrock and created a water-filled pool for the organics that has long-since frozen over. However, calculations suggest that this liquid water pool full of organics may have stayed partially liquid for hundreds of thousands of years in the subsurface. This is a location where we can study: “what happens if you take a bunch of complex organics and add water?” How far along the path to life could they get before the snapshot was frozen?
Wildass hypothesis I just pulled out of my ass with an undergraduate degree in applied physics: maybe interaction with particles emerging from quantum vacuum?
Okay, that sounds like great technobabble. I’m going to watch star trek now ;)
It’s probably not that the light is losing energy it’s just that the distance it travels over time (the time we “know” is supposed to take for a given distance) appears compressed because of unknown/unseen gravitational forces.
Think of it like this: If there were only one star in the universe and it emits a particle of light we could calculate the distance it would travel over time. Yet we know that star will still have a gravitational effect on that light… No matter how far away it gets.
That’s what they mean by light “losing energy”. Is the energy actually “lost”? Not really. Is this slowing (aka appearance of lost energy) caused by dark energy/dark matter or something more fundamental like spacetime itself being stretched or compressed due to the gravity of astronomical objects we can see or “dark matter”/“dark energy” or… ? We don’t really know for certain yet!
It’s probably not that the light is losing energy it’s just that the distance it travels over time (the time we “know” is supposed to take for a given distance) appears compressed because of unknown/unseen gravitational forces.
This doesn’t seem to be at all what tired light proposes though. What you’re explaining sounds like red-shift due to an expanding universe. From what I can tell they claim it actually loses energy through interaction with “other things” in the universe.
This doesn’t answer the question in the context of this theory, but the current understanding is that light does lose energy as it travels through expanding space. As the space it’s in expands, the wavelength gets longer, and the energy goes down. It doesn’t go anywhere; energy just isn’t conserved in an expanding space-time.
If the light loses energy, then it must surely lose it to something? And if your last point that energy isn’t being conserved in our universe, in which case we are either in some deep shit with the first law of thermodynamics, or our universe isn’t an isolated system.
The thing about photons is that they redshift, losing energy as space expands. If we keep track of a certain fixed number of photons, the number stays constant while the energy per photon decreases, so the total energy decreases.
Ok. Smarter people probably thought of this, and probably found my hypothesis to be impossible. But what if… It is the the other way around. What if photons are losing energy because they are expanding spacetime. Like tiny little springs expanding out.
Further into the article he says that, "It would be irresponsible of me not to mention that plenty of experts in cosmology or GR would not put it in these terms. We all agree on the science; there are just divergent views on what words to attach to the science. In particular, a lot of folks would want to say “energy is conserved in general relativity, it’s just that you have to include the energy of the gravitational field along with the energy of matter and radiation and so on.” "
So energy is conserved on the whole, it’s just not conserved if you consider photons apart from their greater context.
The energy is actually not conserved across the universe in general relativity, as it is currently understood. Conversation of energy is due to the time symmetry, which the expansion of space breaks.
BTW, thanks! This comment sent me down a fascinating rabbit hole. It had simply never occurred to me that energy conversation didn’t apply in an expanding universe!
“Energy is conserved in general relativity, it’s just that you have to include the energy of the gravitational field along with the energy of matter and radiation and so on.”
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