See Earth's Surface from the Past: Resolution Possible?

In summary, the conversation discusses the possibility of observing the Earth from a distant location and the limitations of doing so due to the speed of light. It also mentions the potential use of a telescope to improve resolution, but notes that at astronomical distances, it would be difficult to see anything as small as a person or animal due to the limited amount of reflected light.
  • #1
GreenAce92
41
0
If you can "catch up" to the light reflected from the Earth at that time in the past. What kind of resolution would you get? Could you zoom into the surface such that people/animals could be visible.
 
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  • #2
A more practical approach would be to observe the reflection of Earth from some distant object, given that nothing can overtake a photon. What kind of distant body would be sufficiently reflective, and where to look for one, is an issue.
 
  • #3
Sadly, you can't "catch up" to the light that was emitted by the Earth since light is the fastest thing in the universe.

But if you're asking what an alien in another star system might see, then it really depends on what he is using to look at the Earth. The bigger the telescope, the better resolution he will have.
 
  • #4
The resolution is the same.

Imagine looking at the Earth from Alpha Centauri right now, you'll see the Earth as it was 4.4 years ago.

The view will be the same weather you traveled via a hot air balloon or via instantaneous teleportation.
 
  • #5
I would say that at astronomical distances, the light reflected by the Earth (which is not that much to start with) gets so spread into space that looking from any single definite location it would be practically impossible to see anything of the size of a person or an animal, no matter how big your telescope was. The amount of photons you could collect would simply be too small.
 

1. How is it possible to see Earth's surface from the past?

Through the use of satellite imagery and remote sensing technology, we are able to capture high-resolution images of Earth's surface and compare them over time to see changes that have occurred.

2. What is the resolution of these images?

The resolution of satellite images can vary depending on the type of satellite and the sensor used. However, the highest resolution images can capture details as small as 30 centimeters on the ground.

3. How far back in time can we see with this technology?

The earliest satellite images date back to the 1960s, but they have limited resolution. With newer technology, we can see changes on Earth's surface from as recent as a few days ago to several years in the past.

4. What types of changes can we see on Earth's surface?

We can see changes such as deforestation, urbanization, glacial retreat, and natural disasters. We can also track changes in land use, water levels, and vegetation over time.

5. How do these images help us understand Earth's past and present?

By comparing satellite images over time, we can see the effects of human activity and natural phenomena on Earth's surface. This information can help us make informed decisions about land use and resource management, as well as monitor and predict potential environmental changes.

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