Good morning, evening and good day. Welcome to another episode of Astronomy Daily,
the podcast where we muck about with space science and stuff for your listening
enjoyment. I'm Steve, your host. It's August fourteen, twenty twenty three.
Dunk Indeed, And in today's payload, we have a new technique that
measures structured light in a single shot, a look at basic astronomy setups,
traveling without moving, and plans for regular moon shuttles the works. So stay
with us on our Astronomy Daily. And would you welcome our co host Hallie.
Hello, everyone, Glad to be down under again. It was nice
to hang out with Tim last week in England. You know I love traveling,
even if it is at the speed of light. Well, it's funny
you should mention traveling. We've got that story about traveling today, the one
about how far we all move. Well, I like to call it traveling
without moving, Hallie, another sci fi reference there, I see, Yes,
there's that one. And we'll be talking about the many, many plans
for getting all the infrastructures to the Moon. So many different projects and industries
and countries are working on lots of stuff to get there. They all want
to get to the lunar surface. There's talk of a colony, mines and
regular shuttle Steve, Yes, that's why it looks looks like Artemus is just
the beginning, So we'll have a look at that later on. And you
have a really confusing story about light. I do. It's about a new
technique to measure structured light. Okay, structured light. It's really exciting stuff.
Well, okay, I believe you're helly. I'd better let you get
to it. I know your legion of super brainy listeners are hungry for that
one. I'll admit that I read this story earlier and it was a bit
scary. Mostly enough with the sci fi references already, fair enough, Okay,
Holly, let's have those short takes. Hold on to your thinking caps.
Structured light waves with spiral phase fronts carry orbital angular momentum OAM, attributed
to the rotational motion of photons. Recently, scientists have been using light waves
with OAM, and these special hellical light beams have become very important in various
advanced technologies like communication, imaging, and quantum information processing. In these technologies,
it's crucial to know the exact structure of these special light beams. However,
this has proven to be quite tricky. Interferometry superimposing a light field with
a known reference field to extract information from the interference, can retrieve OAM spectrum
information using a camera. As the camera only records the intensity of the interference,
the measurement technique encounters additional crosstalk known as signal signal beat interference SSBI,
which complicates the retrieval process. It's like hearing multiple overlapping sounds, making it
difficult to distinguish the original notes. In a recent breakthrough reported in Advanced Photonics,
researchers from sun yats And University and a call polytechnique Fader al Deloson used
a powerful mathematical tool called the Kramer's chronic relation, which helps with understanding and
solving the problem. This tool enabled them to untangle the complex helical light pattern
from the camera's intensity only measurements for single shot retrieval. In simple on axis
interferometry, exploring the duality between the time frequency and ASIMITHOAM domains, they apply
the Kramer's chronic approach to investigate various OAM fields, including Talbot's self imaged pedals
and fractional OAM modes. The new measurement technique has great potential for advancing technologies
that rely on these special light patterns. According to corresponding author Gentchi, who
now a post doc at Labrator Castler Brassel A call Norma's Superior France. The
proposed method can also be generalized for OAM beams with complex radial structures, making
it a powerful technique for real time measurement of structured light fields simply by a
snapshot with a camera compared to conventional on access interferometry. The Kramer's chronic method
demonstrated by the researchers not only accelerates the measurement, but also makes it much
simpler and cost effective. Thanks to this new technique, scientists have gained a
powerful means to unlock the secrets of structured light waves with OAM. This breakthrough
has the potential to revolutionize various technologies, paving the way for exciting advancements in
the field of structured light in the near future. Seeing Saturn's rings through a
telescope can be an awe inspiring experience. Now is a great time to check
them out. Many amateur astronomers use a backyard telescope to see Saturn, and
seeing the ringed planet through a telescope epiece is one of the most exciting moments
for any amateur skywatcher. Any enthusiast state that seeing Saturn through a telescope was
the reason they became fascinated in space for life. Keep in mind that you
probably won't see a NASA quality image of Saturn using a backyard telescope, but
so many have been surprised at how satisfying a real time view of this planet
is it's definitely worth a try. Many beginners start out with a simple four
point five dobsony and telescope, which features a large aperture for its price range
and is a good starter telescope. This affordable telescope has enough power and magnification
to see Saturn's rings in all their glory. Planets like Saturn and Jupiter are
usually easy to spot. They look like bright stars. Check for their location
with an app, and then use your telescope to reveal their true identity.
Generally speaking, the size of the planet in your field of view will depend
on the equipment you are using, but this comes with experience and know how
with some practice and experience, you'll be visualizing great live moments with the giants
of our Solar system. Bowing Starliner Crude Flight Test CEFT, which will carry
astronauts Berry Abutch Wilmore, and Sunita Suni Williams to the International Space Station ISS,
is now delayed to next year, with the earliest chance for launch in
March. However, Boeing is still confident it will complete the six crude flights
ordered by NASA despite the planned demise of the ISS in twenty thirty. NASA
and Bowing share the updated launch information in a press briefing on Monday, August
seventh. The Crew Space Transportation one hundred scst A one hundred Starliner was supposed
to launch its first crude flight on July twenty first, but Bowing found several
issues that could have posed a threat to the safety of the astronauts, such
as flammable tape and weak parachute soft links, causing yet another mission delay.
Bowing cst A one hundred Starliner, along with SpaceX's Crew Dragon, is part
of NASA's Commercial Crew Transportation Capability cct CAP, which aims to have two vehicles
carry American astronauts and cargo to the ISS on rotation throughout the year, with
the goal of ending the nation's soul reliance on Russia. According to the Space
Agency, the companies were selected in twenty fourteen for the contract, and while
SpaceX has almost completed seven crew trips to the station, Bowing Starliner has been
plagued with delays spanning years. And that's the short takes for today. You're
listening to the Yes, it's good to say that Bowing is being very careful
with their crew or would not take that away from them by I mean,
in recent years we've seen lots of delays with Crewe flots and so on.
But I really hope that Bowing can pull the full pull out all the stall
and get Starliner operational to the point where we see more activity. This is
just another step forward in getting all of those plans together. For those grandiose
plans of getting a colony and mining operations on the Moon. I mean,
who knows if that's a good thing or a bad thing. Will just see
how it goes. I mean, human history has shown that wherever we see
opportunity, that's where we invest our activity. So let's just see how it
all unfolds. Now, do you remember the comment in Dune by Frank Herbert
where the guild navigators would fold space and they would do this thing where they
call traveling without moving. Now, whether you're a frequent jet setter or a
couch potato like me, sorry, you'd travel much more than you would imagine.
In fact, you'd probably be even true if you were to stay perfectly
motionless your entire life. How far, on average does a person travel in
their lifetime. The answer depends on whether or not you consider Earth an actual
vehicle. As for the distance on Earth's surface, a typically human would travel
thirty thousand to fifty thousand miles or up to eighty thousand kilometers in their lifetime,
though some globe trot is, like my fabled brother Andrew from Space Nuts,
would probably go much further than that. Consider a most people accumulate the
majority of this mileage from commutes and quick errands. That's an impressively large distance,
enough to circumnavigate the globe at least once. But large as it is,
the number of pales in comparison to the motion we get by simply hitching
a ride on our planet. It spins on its axis, and because Earth
is mostly solid, it rotates on a single as a single rigid body,
essentially meaning that everywhere on the planet experiences the same angular speed. In every
one travels a full circle every twenty four hours. But if you're to stand
on the North or South geographic poles, you probably wouldn't actually travel anywhere.
You just rotate or spin around and around. Those on the equator, however,
would get tremendous amount of linear speed thanks to this rotation, roughly a
thousand miles per hour or sixteen hundred kilometers per hour. Most people don't live
on the equator, however, so we can say that the average human is
constantly traveling at roughly nine hundred and thirty miles per hour or fifteen hundred kilometers
per hour. As we see, precision doesn't really matter in this equation,
but when you add up over roughly an eighty year lifespan, each person travels
around six hundred million miles or a billion kilometers in a lifetime. That's a
tremendous leap above the travel we do on earth surface, But we're just getting
warmed up. In addition to rotating the Earth's orbits the sun that orbit is
an ellipse, which causes our planet to occasionally move more quickly or slowly depend
on it's a distance from the Sun, but on average, Earth's orbital speed
is about nineteen miles per second or thirty kilometers per second. That's about six
hundred million miles one billion kilometers every year, So over a lifetime, each
of us travels roughly fifteen billion miles or eighty billion kilometers, which again dwarfs
the distance we travel due slowly to our rotation of our planet. But Earth
is not the only object in motion in the universe. The Sun travels in
a long, lazy orbit around the center of the Milky Way galaxy. Of
these galactic years, it takes roughly two hundred and thirty million Earth years to
complete. To put that into perspective, life first rose on Earth, so
they say around sixty seventeen galactic years ago, and in only twenty five more
galactic years the Sun will die. So the story goes. Compared with these
enormous galactic scales, a human lifetime is barely perceptible and the Sun barely along
its orbit. But on a human scale it's almost incomprehensible due to the motion
of the Sun orbiting the center of the Milky Way, each of us will
travel around three hundred and seventy million miles six hundred billion kilometers in a lifetime.
And it doesn't stop there. Our entire galaxy is in motion too.
All galaxies are on average flying away from each other, but that's due to
the expansion of the universe. On top of that expansion, each galaxy has
some motion of its own, something astronomers dubbed peculiar velocity. You might have
noticed this in some nightclubs, perhaps. For example, the Milky Way is
on a collision course with our nearest neighbor, the and A galaxy. The
mutual gravitation attraction is enough to overwhelm the general expansion of the universe, and
in about five billion years, so the story goes, these galaxies will begin
to merge. On top of that, both the Milky Way and the Andromeda
are headed toward the Virgo Cluster, a massive cluster of galaxies about sixty five
million light years away. Beyond that, the Virgo Cluster and its surrounded galaxies
are all headed toward the Greater Tractor, which is the center of our supercluster
called Laneacre Astronomers can calculate the combined motion of these gravitational influences by observing the
cosmic microwave background, which is composed of radiation at least when our universe cooled
from plasma state when it was only three hundred eighty thousand years old, It
completely soaks the universe and is the same to one part in a million across
the entire sky. An emotion in the universe will be visible in the CMB.
Light in the direction we're headed will get Doppler shifted to higher frequencies blue
shift, and light in the direction we're moving away from will be shifted to
lower frequencies redshift. By measuring this shift, astronomers can calculate our total velocity
through the universe, and those measurements give a number of a round three hundred
and ninety miles per second. That's six hundred thirty kilometers per second. When
you add up that over an eighty year lifespan, it gives you a total
movement of nine hundred and thirty billion miles or one point five trillion kilometers.
Even if you never leave home, you will still travel that enormous distance,
and that's quite an accomplishment. Now. I mentioned earlier on a little bit
about the plans to send shuttles to the Moon. Now, multiple space agencies
planned to send astronauts, cosmonauts, and tyconnots to the Moon in coming years
in long term goal of establishing permanent human residents there. This is includes NASSA
led Artemis program, which aims to create a sustained program of lunar exploration and
development by the decades, and there's also a competing Russian Chinese International Lunar Research
Station effort to create a series of facilities on the surface and or in orbit
on the Moon that will enable lucrative research. Beyond these government led programs,
there are many companies and non government organizations hoping to conduct regular trips to the
Moon, either for the sake of learner tourism, oh dear and mining to
build international Moon Village that would act as a spiritual for the want of a
better term successor to the International Space Station. These plans will require a lot
of cargo and freight moving between Earth and the Moon well into the next decade,
which is no easy task, as you can imagine. To address this,
a team of us UK researchers recently released a research paper on the subject
to optimize trajectories for traveling between the Earth and the Moon. The team consisted
of Professor Emeritus Thomas Carter from the Eastern Connecticut State University and mathematical scienceist Professor
Mayahomy from the Worcester Polytechnic Institute. For the sake of their study, the
preprint of which is available online, Carter, on whom he explained how a
shuttle could transport supplies to a lunar outpost and carry back resources extracted from the
surface. Now. Based on their calculations, they concluded that a trajectory that
places the shuttle into an elliptical orbit and minimizes thrust requirements would be optimal.
During the Space Race, both NASA and the Soviet Space Program relied on free
return trajectories to send missions to demon This consisted of using the Moon's gravitational pull
to perform a figure eight shaped maneuver, resulting the spacecraft returning home with only
minimal orbit adjustments, minimizing them out of propellant needed. The orbits of Artemus
missions will be similar to the Apollo predecessors in that they will also perform the
figure eight flights that end with a splashdown in the ocean. In other words,
these missions will be one way trips. But beyond returning astronauts to the
Moon, assembling the lunar Gateway and establishing the Artemus base camp on the surface,
the long term aim is to use the artemas infrastructure to create a permanent
human presence on the Moon. There's also the need to keep things cost effective,
of course, which makes launching heavy payloads from the surface to the Moon
in effission. Professor whom you explained, one of the functions is to avoid
sending large loads to low Earth orbits. Instead, we use capsules with provisions
and replacements for astronauts. To accomplish lunar settlements with minimum cost, we need
something similar to the ISS but with an orbit around the Earth and the Moon.
This shuttle will never land on Earth or the Moon. Capsules from Earth
will dock with it and when it is close to Earth, and similarly,
capsules from the Moon will dock with it when it is near the Moon.
This will avoid the need to lift large loads from Earth or the Moon,
and this will save a lot of money and resources. However, the shuttles
will need engines and propellant to keep this shuttle in orbit, as it will
is subject to gravitational perturbations from the Earth, the Moon, and the Sun,
while the shuttle will not. Why the massive thrusters and propellant tanks needed
to break free of Earth's gravity. Engines and propellant add significant amounts of mass
to emission, which drives up costs. To address this, Hoomie and Carter
considered maneuvers that would minimize fuel consumption and allowing the shuttle to circle the Earth
Moon system in a reasonable amount of time. The process we used to obtain
our results was to develop proper mathematical models based on gravitational forces of Earth,
Moon in the Sun that impact the orbit of the shuttle, said Hermie.
From this, they determine that a circular elliptical orbit with a peraging near the
Earth and an apergy beyond the Moon would be an optimal trajectory. Only minimal
thrust would be required for course corrections. This type of shuttle and trajectory,
said Whomie, is needed for any plans to establish a permanent human presence on
the Moon, but could also lead to a thriving Earth Moon economy That was
a real mixed bag today. Oh it's sure, is Halle, And we'll
do it all again next week, won't we Halle? Absolutely? Now where
can they find us? Well, you can go to Space Nuts podcast group
on Facebook and that's a great place for interactions. Love to see you all
there. And you can listen to all the back editions of our parent podcast,
Space Nuts with a Productly and professor Fred Watson, and all the back
editions of Astronomy Daily with myself, Tim Gibbs and Halley of course at space
nuts dot io and bytes dot com. So that's where you gave for all
your back editions of all our podcasts. And that's it from us for another
week. We'd love to see you next week here on Astronomy Daily. Bye
for now, be your whole big dunkle