<p>That is, if you use the cosmic distance ladder method, and a value of about 73.5 for the Hubble constant....</p>
<p>But, if you plug in the Planck CMB value of about 67.5, you get a distance of about 14.5 billion light years, beyond which objects seem to be moving away from us at superluminal speeds...</p>
<p>Are those values correct?</p>

CC BY-SA 4.0
2021-03-08T21:29:59.887Z
There are several questions with answers that address this.  Try using "Search on Astronomy" for "faster than light" The suggested duplicate seems to be the canonical answer.  The summary is that "it's because the spacetime between us and the galaxy is stretching, so the notion of speed (as rate of change of distance) is a little *stretched*  pun intended.
James K
CC BY-SA 4.0
2021-03-08T23:06:06.067Z
tl;dr Yes, the numbers are roughly correct. We easily see galaxies recede faster than the speed of light. In fact, any galaxy with a redshift z > ~1.5.
pela
<observational-astronomy><cosmology><hubble-constant><cosmological-horizon><cosmic-microwave-background>
Objects beyond 13.3 billion light-years away are (apparently) moving away from us at faster-than-light speeds?
Kurt Hikes
# Objects beyond 13.3 billion light-years away are (apparently) moving away from us at faster-than-light speeds?

(Asked by: username_0 on 2021-03-08)

That is, if you use the cosmic distance ladder method, and a value of about 73.5 for the Hubble constant....

But, if you plug in the Planck CMB value of about 67.5, you get a distance of about 14.5 billion light years, beyond which objects seem to be moving away from us at superluminal speeds...

Are those values correct?

**Tags:** observational-astronomy, cosmology, hubble-constant, cosmological-horizon, cosmic-microwave-background

> **Comments:**
> **username_1**: There are several questions with answers that address this.  Try using "Search on Astronomy" for "faster than light" The suggested duplicate seems to be the canonical answer.  The summary is that "it's because the spacetime between us and the galaxy is stretching, so the notion of speed (as rate of change of distance) is a little *stretched*  pun intended.  
> **username_2**: tl;dr Yes, the numbers are roughly correct. We easily see galaxies recede faster than the speed of light. In fact, any galaxy with a redshift z > ~1.5.  

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