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E

Equation of time

(Last edited: Friday, 28 April 2023, 6:09 PM)

https://pro2-bar-s3-cdn-cf3.myportfolio.com/cf59f354b34391ef9ddbec41a1409bef/ece2a825-e54c-4ea4-a57c-bc1f3e901591_rw_1920.jpg?h=e8d9d5ab3208bd43c08d7702b9ec2c74

Source:

https://pro2-bar-s3-cdn-cf3.myportfolio.com/cf59f354b34391ef9ddbec41a1409bef/ece2a825-e54c-4ea4-a57c-bc1f3e901591_rw_1920.jpg?h=e8d9d5ab3208bd43c08d7702b9ec2c74

Short Definition:

The equation of time is a result of the difference between the daytime on Earth and the position of the sun.


Detailed Definition:

The equation of time exists because the orbit of the Earth around the sun is elliptical (where the orbit is not centered around the sun) and not circular which results in a difference in speed around the elliptical orbit as a difference in the length of the Earth days.

The equation is the following:

EOT =GHA- GMHA where EOT is the equation of time, GHA is the Greenwich Hour Angle of the apparent sun and GMHA is the Universal Time-Off.

As a result, the 21./22. December is the shortest day of a year, the real local time (WOZ) results in uneven long hours and the middle time (MOZ) results in a sun orbit, which is unsymmetrical to the time.

Etymology:

Equation - latin aequationem (" an equal distribution, a sharing in common")

Time -  Proto-Germanic Timon-/timi ("Time, proper time")

Sample Sentence(s):

" The equation of time is the reason a Analemma( a diagramm which shows the position of the sun from one point at a specific time over a year) can be seen"


Translation:

French:

équationdutemps

German:

Zeitgleichung


Polish:
Równanieczasu

Swedish:
tidsekvation

Links to Videos/Articles:
https://youtu.be/Mx9AJJSKIL4
https://astro.dur.ac.uk/~ams/users/equation_of_time.html
https://www.youtube.com/watch?v=hn0js5EzmEc





Euclid mission

(Last edited: Friday, 28 April 2023, 6:09 PM)

The device which will be used in the Euclid mission, is shown

Image source:

https://www.esa.int/var/esa/storage/images/esa_multimedia/images/2019/09/euclid_spacecraft/19709645-1-eng-GB/Euclid_spacecraft.jpg

Short Definition:

The euclid mission is project, being prepared by ESA to investigate dark matter as well as dark energy. At this moment, it is planned to launch the mission in the year 2023 (no specific date is set yet).

The planned time the mission will take is set for six years and can be extended, but is limited by the amount of cold gas propulsion.


Detailed definition:

ESA has started the euclid mission is a project to try to investigate dark matter as well as dark energy. The spacecraft consists of a camera in the visible wavelength and a camera /spectrometer which works in the near-infrared area.

It will launch from the Europe'sSpaceport in Kourou, which is located in French Guiana, and will move in an orbit which is halo shaped around the Sun-Earth Lagrange point.

Another aspect which will be inspected by the mission is the reason why the expansion of the universe in accelerating and how the evolution of the universe took place, to gain more information about fundamental physics and cosmology.


Etymology:

Euclid - Greek euclid ("renowned, glorious")

mission -Latin missionem ("act of sending a dispatching; a release, a setting at liberty")


Sample Sentence:

The Euclid mission is expected to bring new knowledge about the history of the universe and dark matter.


Translations:

French: MissionEuclide

German:Euklid-Mission

Polish: MisjaEuclid

Swedish: UppdragEuclid


Links to Articles:

https://www.jpl.nasa.gov/missions/euclid

https://sci.esa.int/web/euclid

https://www.nasa.gov/mission_pages/euclid/main/index.html





EVA

(Last edited: Friday, 28 April 2023, 6:09 PM)

Astronaut Steve Robinson performing an EVA during STS-114 mission.

Source: Wikipedia/NASA

Short Definition:
EVA is an act of performing different activities outside your spaceship while in orbit. This could include repairing, attaching or other experiments.

Detailed Definition:
Performing an EVA can refer to activities such as spacewalks, where astronauts leave the spacecraft to work in the vacuum of space, as well as other tasks such as inspections or repairs on the exterior of the spacecraft. EVAs are a common part of space exploration and are conducted by astronauts in a variety of different settings, including the International Space Station and during lunar, or in the future, planetary missions.

Etymology:
EVA stands for Extravehicular Activity

Sample Sentence(s):
Astronauts on the ISS are preparing to perform an EVA.
Yesterday's EVA was completed successfully.

Translations:

French:
Sortie extravéhiculaire

German:
Außenbordeinsatz

Polish:
Spacer kosmiczny

Swedish:
Rymdpromenad

Links to Videos/Articles:
https://www.nasa.gov/content/extravehicular-activities/
https://en.wikipedia.org/wiki/Extravehicular_activity

Event Horizon

(Last edited: Friday, 28 April 2023, 6:09 PM)


Source(s):


Short Definition:

The event horizon of a black hole is a threshold around the black hole where the escape velocity surpasses the speed of light. It is also referred to as a boundary beyond which events cannot affect an observer.

Detailed Definition:

The term event horizon is used to describe the phenomena of a very strong gravitational pull in the vicinity of a massive and compact object, which is able to prevent even light from escaping. The escape velocity is a threshold value for which the event horizon occurs. It is the velocity needed for an object to overcome the forces acting due to the presence of an enormous mass. If it is greater than the speed of light, it is impossible to witness any event taking place past the event horizon.

Etymology:

The term was first used by Wolfgang Rindler in the 1950s.

Sample Sentence(s):

"The event horizon is the ultimate prison wall - one can get in but never get out."

                                             - Avi Loeb, chair of astronomy at Harvard University.

Translations of Terms/Concepts into Partner Languages

French: Horizon des événements

German: der Ereignishorizont

Polish: Horyzont zdarzeń

Swedish: Händelsehorisont


Links to Videos/Articles:

https://www.space.com/black-holes-event-horizon-explained.html

https://astronomy.com/news/2019/04/the-event-horizon-telescope-may-soon-release-first-ever-black-hole-image


Expansion of the universe

(Last edited: Friday, 28 April 2023, 6:09 PM)

Image/Video/Audio Source:

https://en.wikipedia.org/wiki/Expansion_of_the_universe#/media/File:CMB_Timeline300_no_WMAP.jpg

Short Definition:

The expansion of the universe is a phenomenon, which describes the inherent property of the universe, where two galaxies that are gravitationally unbound tend to increase the distance to each other and the rate of expansion is even accelerating. Far away parts of the observable universe will not be observable in the near future, because the velocity of expansion is higher than light speed from an outside perspective.

Detailed Definition:

The expansion of the universe is a phenomenon, which explains an inherent property of the universe to expand. The fact that the universe seems to expand, was first doubted because of the gravitational force and the fact that releases of energy like the big bang should normally lose power and should slow over time, but the opposite was observed. The elusive culprit was found quite fast. Dark matter is to be responsible for this phenomenon, but since we know even less about dark matter than about the expansion of the universe, details of how and why it expands are still unknown. 

This expansion occurs at every location of the universe and only gravitationally bound galaxies will be able to observe each other, because unbound galaxies will escape our observable universe at some point. The expansion can in some way be compared to an elastic rubber band, where the distances also increase when you stretch it, but not literally and not on a human scale. It is more that at a scale so far zoomed out, that the universe looks like a cosmic fluid and at this scale it is apparent that the density is decreasing over time. There are three viable methods to measure this expansion. One is based on redshifts, while another on the cosmic distance ladder. Those measurements gave non-matching results, and so 2018 information from gravitational waves made it possible to determine the rate of expansion even more precisely.

Etymology:

Expansion à from Latin expandere à spread out

Universeà from Old French univers à from Latin universum

Sample Sentence(s):

In a thought experiment of an ascending civilization in a faraway galaxy in the far future, they would only be able to observe their neighbouring galaxies and will think  that this is all there is to the universe and all this due to an expansion of the universe.

 

The rate of expansion of the universe is thought to be accelerating.


French:

Expansion de l'univers

German:

Ausdehnung des Universums

Polish:

Ekspansja wszechświata

Swedish:

Utvidgning av universum

Links to Videos/Articles:

Expansion of the universe - Wikipedia










F

Fluid shift in the human body

(Last edited: Monday, 5 June 2023, 2:00 PM)



Image Source:

S, M. (2023, June 01). Illustration of fluid distribution. self. self-made

Short Definition:

The fluid shift in the body is an adaption to the reduced gravitation force in space. This results in a shift of the body fluids from the lower body to the upper body.

Detailed Definition:

When a human body is placed on the earth surface, it has a hydrostatic (gravitational) blood pressure gradient and every body region has a different arterial pressure.

In the reduced gravity of space, the hydrostatic pressure in the arteries and veins is altered to a homogeneous arterial pressure in all regions (which is the original arterial pressure of the hearth), which results in the shifted fluid distribution through the body.

The human body reduces the volume of the total fluid and after the space resident, the fluid is shifted because of the returned gravity force.

This phenomenon can cause several issues like cardiac arrhytmia, muscular athropy and visual problems (because the globe is flattened, the blood flow is changed slightly and the diamteter of the optical nerve can increase).


Etymology:
fluid - Latin fluidus ("fluid, flowing, moist")
shift - Proto-Germanic skiftan (" to divide, change, seperate")

Sample sentence(s):

A medical effect of a space flight may be a fluid shift.

Nasa is studying the effect of the fluid shift and how it affects changes in vision.

Translation:

French:

déplacement du fluide

German:

Flüssigkeitsverschiebung 

Polish:

Przemieszczenie płynu

Swedish:

vätskeförskjutning


Links to Videos/Articles:

https://www.nasa.gov/content/fluid-shifts-study-advances-journey-to-mars

https://ntrs.nasa.gov/citations/20150001888



Frequency

(Last edited: Friday, 28 April 2023, 6:09 PM)


Image Source:



Short Definition:

A frequency (f) is a physical variable which measures how often a event is repeated in a defined period of time.  

The SI-unit is Hertz (hz) or s^-1.  

A common scenario in which the frequency is used, is in a wave, in which it can be calculated by measuring the Period T (the time it takes to complete one cycle) and using the equation: f = 1/T 


Detailed Definition:
Another equation by which the frequency can be calculated, is the following with \( \lambda = \) wavelength and v= phase velocity (if the wave is detected in a vacuum, the following applies: v=c)
\( f = v/ \lambda \).

There exist two special types of frequency, the angular frequency and the spatial frequency, which will be explained in the following:
The angular frequency (ω) describes how fast a vibration / wave is occurring by measuring the overstepped phase angle of the vibration / wave in a defined time period. This frequency can be calculated in the already introduced frequency f by using the following equation:
\( \omega = 2 \pi f = 2 \pi /T \).

The spatial frequency (ξ) measures how often sinusoidal components (components of a sinusoidal wave) of a structure repeat per unit of distance, which can be calculated by using the following equation:
\( \xi = 1/ \lambda = f/v \).

Etymology:
frequency - Latin frequentia (" an assembling in great numbers, a crowding; crowd, multitude, thong")

Sample Sentence(s):
The frequency can be identified by calculating the inverse of the period T.
The frequency is a variable which can characterize a wave.

Translations:
French: Fréquence

German: Frequenz


Polish: Częstotliwość

Swedish: Frekvens


Links to Videos/Articles:
https://www.britannica.com/science/frequency-physics
https://www.youtube.com/watch?v=6WIDhLeryWM
https://www.physicsclassroom.com/class/waves/Lesson-2/Frequency-and-Period-of-a-Wave



G

Galaxy

(Last edited: Friday, 28 April 2023, 6:09 PM)


Image/Video/Audio Source:

Short Definition:
A galaxy is a system composed of a star and an interstellar matter that is held together by the gravity force.

Detailed Definition:
A galaxy is a vast collection of stars, their solar systems, gas, and dust. In the centre of the galaxy a massive black hole is placed. Galaxies have different shapes from one another, with variations deriving from how the systems were created and later evolved. A few galaxies resemble our own in spiral shape. They possess curved arms that give it a pinwheel-like appearance. Others have smooth surfaces and oval forms. Scientists refer to them as elliptical galaxies. There are galaxies that are neither spirals nor ovals, either. They mimic blobs and have amorphous forms. Each of these galaxies emits light that we can see from its stars. In the future some galaxies will collide like NGC 4567 and NGC 4568 (commonly referred to as the Butterfly galaxies) started to do so and some will drift apart that the light from its stars will not reach the Earth.

Etymology:
Old French from medieval Latin galaxia, from Greek galaxias (kuklos) ‘milky (vault)’, from gala, galakt-‘milk’.

Sample Sentence(s):
When the sky is dark, centre of our galaxy is perfectly visible.

Translations:
French:
Une galaxie

German:
die Galaxie

Polish:
Galaktyka

Swedish:
En galax

Spanish:
Una galaxia

Links to Videos/Articles:
https://spaceplace.nasa.gov/galaxy/en/
https://en.wikipedia.org/wiki/Galaxy
https://www.britannica.com/science/galaxy
https://edition.cnn.com/2022/08/10/world/colliding-galaxies-gemini-north-image-scn/index.html



Galaxy Evolution

(Last edited: Friday, 28 April 2023, 6:09 PM)

Picture: Model of Evolution of Galaxy

Image/Video/Audio Source:

https://upload.wikimedia.org/wikipedia/commons/a/a3/Evolution_in_slow_motion.jpg

Short Definition:

Galaxy evolution or evolution of galaxy is a term that we have used for understanding the formation process and changes of galaxies since the beginning that made up the known universe. The term galaxy evolution also represents the models we form about the universe filled by the observed photons and the expansion since the big bang. At this point, the sizes, shapes and contents of all galaxies give us an idea about the formation and evolution of the universe.

Detailed Definition:

Galaxy evolution is a term used to understand the structure of the universe and the ongoing formation processes by comparing the morphology, brightness and content of galaxies with each other. The term galaxy evolution here studies galaxies in four main groups. These are Elliptical Galaxies, Lenticular Galaxies, Spiral Galaxies, and Irregular galaxies. The evolution process of galaxies in these four groups is examined under three main headings. These are Passive evolution (The state where the galaxy does not interact with any other galaxy [interactions or mergers] and thus does not produce star formations.), Interactions and Mergers (The state in which galaxies are affected by interacting with other galaxies), Secular Evolution (Situation in which processes by internal changes of galaxies affect their colour, luminosity and shape.)

Etymology:

From Latin ‘Galaxias’ and From Latin ‘ēvolūtiōnis’ (Unrolling/Unfolding)

Sample Sentence(s):

Radio telescopes have played a pivotal role in the understanding of galactic evolution.’’

(Galaxy Evolution, Cosmology and Dark Energy. (2018, May 30). Public Website. 

https://www.skatelescope.org/galaxyevolution/)

‘’Understanding how black holes shape their host galaxies is part of the study of galactic structure and evolution.’’

(Galaxy Formation and Evolution | Center for Astrophysics. (n.d.). https://www.cfa.harvard.edu/research/topic/galaxy-formation-and-evolution)

Translations of Terms/Concepts into Partner Languages:

French:

Évolution de la galaxie

German:

Galaxienentwicklung

Polish:

Ewolucja galaktyki

Swedish:

Utveckling av galaxer

Turkish:

Galaksi Evrimi

Links to Videos/Articles:

https://www.britannica.com/science/galaxy/Evolution-of-galaxies-and-quasars

https://www.jwst.nasa.gov/content/science/galaxies.html

https://www.skatelescope.org/galaxyevolution/

https://www.cfa.harvard.edu/research/topic/galaxy-formation-and-evolution

https://sites.astro.caltech.edu/~george/ay20/eaa-galevol.pdf

https://astronomy.swin.edu.au/cosmos/E/evolution+of+galaxies

https://www.youtube.com/watch?v=Rdd9KAUcvgQ&ab_channel=TakayukiSaitoh

https://www.youtube.com/watch?v=_WtvU4Xn2UE&ab_channel=CaltechAstro



Galaxy Merger

(Last edited: Friday, 28 April 2023, 6:09 PM)


Source:

https://www.eso.org/public/images/1016-galaxy_formation_merger/

Short Definition:

A galaxy merger is the phenomenon of two or more galaxies colliding with each other, resulting in the formation of a new, enlarged galaxy.

Detailed Definition:

A galaxy merger occurs when two or more galaxies collide with each other, leading to the creation of a larger galaxy. Galaxy mergers are the most violent type of galaxy interaction. When a collision of several galaxies occurs, the stars and dark matter in each of them become affected, which has influence on both the orbits of the stars and the shape of the newly formed galaxy. 

During a merger, an increase in star formation can be observed, as the friction interaction of gas and dust contributes to the raise of energy in the resulting system. Galaxy mergers provide astronomers with the merger rate, which is a fundamental measurement of galaxy evolution and sheds some light on how galaxies have increased in size over time.

Etymology:

merge - Latin mergere"to dip, dip in, immerse, plunge"

galaxy - Late Latin galaxias - Greek galaxías

Sample Sentence(s):

Galaxy mergers can be simulated in computers, to learn more about galaxy formation.

Translations of Terms/Concepts into Partner Languages

French: Fusion de galaxies

German: Galaxienfusion

Polish: Fuzja galaktyk

Swedish: Galaxsammanslagning


Links to Videos/Articles:

https://www.eso.org/public/images/1016-galaxy_formation_merger/

https://www.thoughtco.com/interacting-galaxies-have-interesting-results-3072045

https://www.youtube.com/watch?v=4disyKG7XtU




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