References
Latest References

Telescopes at Best Buy: Deals in stock 2025
By Ruth Gaukrodger last updated
We've combed through all the telescopes at Best Buy, looking for new deals and checking stock levels on popular models.

Telescopes at Walmart in 2025: Best deals
By Ruth Gaukrodger last updated
There are several discounts on Celestron and other telescopes at Walmart, get them before they're gone!

What is dark matter?
By Nola Taylor Tillman last updated
Reference Roughly 80% of the mass of the universe is made up of dark matter, a material that scientists cannot directly observe. So why do scientists think it dominates?

Telescopes on Amazon: The best deals 2025
By Ruth Gaukrodger last updated
Telescopes on Amazon are in abundance, so we've scoped out the best deals that are available.

Telescope deals 2025: save hundreds with these stargazing bargains
By Jase Parnell-Brookes last updated
Deals We've scoped out the best telescope deals available this year featuring top models from reputable retailers.

Special relativity explained: Einstein's mind-bending theory of space, time and light
By Vicky Stein, Daisy Dobrijevic last updated
Einstein's paper on special relativity revolutionized light, light speed, matter and energy with a deceptively simple equation.

Best budget telescopes under $500 2025: Explore the night sky for less
By Jase Parnell-Brookes last updated
Deals We've rounded up the best budget telescopes under $500 so you can survey the night sky regardless of your budget.

Best telescopes for seeing planets in 2025
By Tom Kerss last updated
Buying Guide The best telescopes for seeing planets give you the best views of our celestial neighbors.
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