Questions tagged [earth]
Questions of the science and space exploration related to Earth.
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What network does the Chandra X-ray Observatory satellite use to communicate with Earth while staying in its orbit?
From a NASA fun facts website How do satellites communicate?:
How do satellites communicate?
Satellites communicate by using radio waves to send signals to the
antennas on the Earth. The antennas ...
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I've loved outer space and the idea of moving to a new planet since forever, but [closed]
Why is it so important that we explore outer space so much even though our own Earth is riddled with so many problems such as poverty, climate change and threats to biodiversity? Why is it important ...
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If we had a video livestream of a clock being sent to Mars, what would we see?
If, you hypothetically started 2 clocks at exactly the same time, and placed one on Earth, and one on a rocket to Mars, and setup a video feed of both clocks, how would they compare as the 2nd clock ...
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How bright would Earthlight be from the surface of the Moon? Can you read under the light of the Earth?
In the lunar sky, the Earth would certainly outshine the Moon from its place in the sky of Earth. However, I can find very little about what it would actually be like.
I am wondering about the size of ...
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When sending a ship to mars what is the optimal travel path [duplicate]
its pretty self explanitory but I need to figure it out but not something from the past a ship that could be sent in the next 5-7 years what would be my time frame using the least amount of fuel and ...
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With increased space exploration missions, are we affecting earth's mass?
This questions may seem naive, but, worth pondering:
As humans keep sending more and more missions to space (outside earth's system), the earth is being affected in the following ways:
Earth is ...
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Longest time between Earth flyby for active space mission
I'm wondering what the longest time was that passed between the first earth flyby and the second.
Lucy did a flyby on earth in October 2022 and will do its last currently planned flyby in 2030. So ...
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Earth-Oblateness-Effect and advance of the apogee?
in our literature it says that the results of the Earth-Oblateness-Effect are as follows:
A regression of the nodes
An advance of the perigee
regarding this i got 2 questions:
1.) What about the ...
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What's the orientation of earth in space if the entire solar system is moving in one direction [closed]
I know that there is nothing north, south, east or west in space there is no reference by which you can tell if apparent north is up, down, left or right.
But as I understand that all planets in the ...
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Can a black hole ever kill Earth?
Earth is presently facing no threat because no black hole is close enough to the solar system to threaten our planet. We think. According to NASA, even if a black hole with the same mass as the sun ...
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What is the velocity of the ISS relative to the Earth's surface?
This was asked once before, but I believe there was no clear answer given and accepted.
The ISS has an orbital period of 92.9 minutes, or 5574 seconds. If it were in a completely equatorial orbit, ...
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If the lights we receive from old galaxies are old, could we see ours if we were in those galaxies? [closed]
I am bit of an amateur in space and astronomy. As far as I understand the light that we receive from those galaxies is old, millions and billions of years old.
A galaxy that is 100 million light years ...
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How to calculate earth's precession using JPL Horizons System?
I'm new to JPL Horizons and understanding how to use the tool efficiently.
I'm looking to extract earth's precession data and understand where we are in the current cycle. I understand we progress 1 ...
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Why all the 'dust' on liftoff?
To bring things back to earth (literally), why is there such a plume of what I can only imagine is dust on liftoff from launchpads on Earth?
Every launch I see from Earth has a huge cloud shooting out ...
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Is there a low Earth orbit with a 24-hour day night cycle?
Are there any possible low-Earth orbits that use precession to match Earth's day/night cycle? So like SSO, but specifically aimed to achieve a 24hr day/night in LEO.
If so, what would its parameters ...
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Shouldn't space junk fall back to Earth on its own? How long will take for a ~1 cm piece of junk in LEO to fall back to Earth on its own for example?
I'm a noob in this subject and know little about space exploration, but I wonder about this every time I read the news:
Wouldn't drag make all space junk fall back to Earth after some time?
I'm ...
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Which deep-space spacecraft flew closest by Earth during a gravitational assist?
The extremely cool NASA JPL video Triumph at Saturn (Part I) is really worth a watch and/or listen. (Don't forget Part II as well!)
At about 26:30 it discusses ...
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Are pictures of Earth' space junk realistic?
Every time I look at a picture that shows the amount of space junk I'm baffled. I can't for the life of me think how anything else being launch into orbit actually makes it without hitting anything ...
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How to calculate the height above the horizon of a geostationary satellite on a given latitude?
Wikipedia's Geostationary orbit; Communications says:
Geostationary communication satellites are useful because they are visible from a large area of the earth's surface, extending 81° away in both ...
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Why is Aurora Australis less popular? [closed]
The Aurora Borealis(Northern Lights), in the North, gets more publicity, than the (Southern Lights) Aurora Australis, Why is it so?
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Does the Moon's orbit intersect the Earth's orbit around the Sun?
I know that the Moon's orbital plane makes an angle of 5 degrees with the Earth's orbital plane or the ecliptic. Also, the Moon's orbit intersects the Earth's orbital plane at two nodes - ascending ...
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How can we mine Near Earth Objects?
After skimming this Worldbuilding SE answer, I wonder if any companies or space agencies have plans in place to mine Near Earth Objects(NEOs) in the future.
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Biggest orbital inclination change done in Earth's orbit
Generally orbital inclination change is said to be (fuel) expensive. What is the biggest orbital inclination change (in degrees) done in Earth's orbit for an orbiting object? Can this be broken down ...
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How much of the total angular momentum of the Earth-Moon system is due to the Moon?
I've read that the total angular momentum of the Earth-Moon system is 3.41x10^41 g.cm^2/s (1). How much of that is due to the Moon? In other words, if the Moon ceased to exist and the Earth ...
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Why are minimum three artificial satellites required for radio-communication all around the Earth?
Artificial satellites orbiting the Earth have important applications for radio-communication around it.
To avoid the blockage of radio-communication around the Earth, multiple satellites can be ...
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If I know the masses, positions, and velocities of two objects, how do I calculate their trajectories under gravity?
I was thinking about the effect of a near-miss with an asteroid upon the orbit of the earth around the Sun. My goal is to figure out a formula I could use for a visualization I'd like to build to get ...
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Do astronauts on ISS notice Earth's seasons?
Has anyone stationed on the ISS for some months reported noticing the changing seasons on Earth in any way like people on the surface do, subconsciously without needing to look up numbers for anything?...
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How to plot this orbit?
I have these data for some orbits, without any explanation about meaning of each datum:
...
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How to convert body coordinate from Sun reference frame to Earth reference frame?
I have the coordinates of a celestial body w.r.t. Sun , expressed as (x,y,z), at a given time.
I need to move this coordinates into a reference frame centered on Earth center, but after reading dozens ...
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Does it make any scientific sense that a comet coming to crush Earth would appear "sideways" from a telescope and on the sky (from Earth)? [closed]
In multiple different movies and fiction, there's the threat of a burning space comet heading for Earth, threatening to kill everyone and destroy the planet.
One example is the animated Comet in ...
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Is Mohs scale of mineral hardness applicable for rocks and minerals of terrestrial planets other than Earth?
The Mohs scale of mineral hardness is a qualitative ordinal scale characterizing scratch resistance of various minerals through the ability of harder material to scratch softer material. Now there is ...
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Should coordinate transformations from J2000 to ITRF93 in quaternions be cyclic?
I used SPICE's pxform at an interval of epochs to determine the transformation from J2000 (inertial) to ITRF93 (Earth body-fixed) frame. Then, I converted these rotation matrices to quaternions with ...
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J2000 to current ECI transformation matrix
I want to find the transformation matrix that converts an ECI frame at some time 't' (lets say t = 1st January 2020) to J2000 ECI frame (that is ECI frame at noon of 1st January 2000). From what I ...
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Earth's Axial Precession and Frame Change [duplicate]
Is Earth's Axial Precession and change in Axial tilt values significant enough to be considered while writing Rotation matrix that converts Body frame into ECEF frame and also while propagating Orbit ...
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magnitude of magnetic anomalies (Earth and Mars)
I've been looking for the magnitude of highest and lowest magnetic anomalies on Earth and Mars (mapped by spacecraft in low orbit), by searching online I couldn't really find a numerical value. From ...
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Why do many Mars missions launch now, if the Hohmann transfer orbit is the most propellant-saving one?
The Hohmann transfer orbit is the most propellant-saving transfer orbit to Mars. When using this kind of transfer, the rover/rocket/etc. starts from Earth when Earth and Mars are in conjunction.
But ...
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Would Earth without water look like Mars? [closed]
I was watching this slideshow of 4K images of the surface of Mars, and I noticed that the surface looked mostly smooth, with the most rugged features being crater impacts (sort of resembling an Earth ...
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Calculate Satellite ground track
I'm trying to find equations to calculate satellite position based on orbit parameters and given time. What I currently have is a mess that is basically giving me bunch of garbage.
What is latitude ...
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Why spacecraft 's trajectory is shown undulating curve on 2D image of earth? [duplicate]
As i am watching live-stream of Demo-2 mission,the trajectory of a capsule is shown curved(like sin wave). In other words, why their trajectory isn't along longitude so that in 2D, the path followed ...
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Earth Live Video Feed in HD?
Is there any space agency that provides a live video of Earth, in HD? Preferably without anything man-made in the way (e.g some ISS robotic arm)?
I want to create a live HD wallpaper of Earth, so I'm ...
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Is it easier to take off from the moon or earth? [closed]
how much mass does the moon have?
how much mass does the earth have?
how much force needed to leave earth
how much force needed to leave the moon
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If the Earth spun clockwise, how would that affect Space Exploration?
If viewed from the North Pole, the Earth spins counter-clockwise.
Because of this, many satellites also orbit in the same direction as you can take advantage of the Earth's rotation and essentially ...
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Can any aspect of the brightness of Martian twilight be determined by Curiosity's photo of Earth? [duplicate]
Curiosity took this image of Earth on Jan. 31, 2014, 80 minutes after sunset.
Stellarium has the Earth >15° above the horizon 80 minutes after sunset on that day.
With Stellarium indicating the ...
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What was the effective magnification of the Mars Reconnaissance Orbiter's HiRISE camera to acquire the detailed image of Earth?
On October 3, 2007 NASA's Mars Reconnaissance Orbiter HiRISE camera acquired this image of the earth and the moon from Mars
The oceans and clouds can be easily distinguished and "the west coast ...
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Could the Apollo astronauts distinguish Earth's continents and oceans from the moon?
This article "Earthshine Reflects Earth's Oceans And Continents From The Dark Side Of The Moon" indicates that the difference in reflection of light from the Earth’s land masses and oceans can be seen ...
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What is the acceleration necessary for a Brachistochrone transfer from Earth to Mars?
With these orbital configurations,
source-Bing
leaving Earth on Aug 16, 2106 and arriving on Mars October 10,2106, what is the lowest continuously-applied acceleration that can make what is ...
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Earth Moon Pork chop plot
Does pork-chop plots exist for Earth-Moon System? I could only find pork-chop plots for Earth-planet systems.Could someone please shed some light on this topic?
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How to determine the distance between where Earth and Mars are two specific dates?
How would I find the solar-system-relative distance between where Earth would be on 2106/8/16 and where Mars would be on 2106/10/16, or any combination of dates.
Image source-Bing
Is there software ...
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Could Breakthrough Starshot be used to deflect asteroids and comets?
Would Breakthrough Starshot be able to deflect an asteroid or comet? I have seen thoughts about using the lasers that would launch Breakthrough Starshot to deflect asteroids or comets: https://www....
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What does Earth's J₂₂ moment look like?
Wikipedia's Geopotential model give's the form of the potential component linked to $J_2$ as
$$u = J_2\frac{P^0_2(\sin \theta)}{r^3} = J_2\frac{1}{r^3}\frac{1}{2} \left(3 \sin^2\theta-1 \right) = ...
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