Flight speed: How fast to notice rapid night/day change?

Hi:

How fast would an airplane need to fly in order to those onboard to
notice changes in darkness/brightness of the sky -- in which the
changes in intensity are significant enough to be noticed in seconds?
E.g. if you are flying towards the darker side of the earth, you'll
notice the sky getting darker each second just by looking outside.
Pretty scary!

Earth rotates around the sun at 1,000 MPH, so the plane would need to
be flying much faster than 1KMPH. Concord planes reached around 1KMPH.


Thanks,

Radium

P.S. Imagine 12:00 PM brightness turning into 12:00 AM darkness in
just 1 hour!!

Radium writes:

How fast would an airplane need to fly in order to those onboard to
notice changes in darkness/brightness of the sky -- in which the
changes in intensity are significant enough to be noticed in seconds?
E.g. if you are flying towards the darker side of the earth, you'll
notice the sky getting darker each second just by looking outside.
Pretty scary!

This requires a speed of thousands of miles per hour, beyond what any
commercial aircraft could do.

If you want scary, a total solar eclipse works very well for that.

"Radium" wrote in message
oups.com...
Hi:

How fast would an airplane need to fly in order to those onboard to
notice changes in darkness/brightness of the sky -- in which the
changes in intensity are significant enough to be noticed in seconds?
E.g. if you are flying towards the darker side of the earth, you'll
notice the sky getting darker each second just by looking outside.
Pretty scary!

Earth rotates around the sun at 1,000 MPH, so the plane would need to
be flying much faster than 1KMPH. Concord planes reached around 1KMPH.


Thanks,

Radium

P.S. Imagine 12:00 PM brightness turning into 12:00 AM darkness in
just 1 hour!!


Imagine 12 Noon or 12 Midnight! There is no 12 PM or 12 AM.

"Radium" wrote in message
oups.com...
Hi:

How fast would an airplane need to fly in order to those onboard to
notice changes in darkness/brightness of the sky -- in which the
changes in intensity are significant enough to be noticed in seconds?
E.g. if you are flying towards the darker side of the earth, you'll
notice the sky getting darker each second just by looking outside.
Pretty scary!

Earth rotates around the sun at 1,000 MPH, so the plane would need to
be flying much faster than 1KMPH. Concord planes reached around 1KMPH.


It depends on the latitude where you are flying not just the speed of the
plane. At the equator it is roughly 1000 miles or 1600km per 1 hour time
zone. As you get closer to the poles it takes less and less time to cross a
time zone at the same speed, when flying for example from the UK to Japan
along the northern border of Russia. Up there a one hour time zone change
(15 degrees longditude) is very roughly 400km rather than about1600km at the
equator. Of course as you get closer to the pole the sun may not set (in
summer) or may not rise (in winter).
At 45 degrees north (e.g. Montreal) you only need to go at about 500mph to
go through time changes as "quickly" as at 1000mph at the equator.

If you travel eastwards you are travelling into the direction of the Earth's
rotation, so everything is apparently speeded up, whereas going west you are
going with the earth's rotation. If you travel west at the equator at about
1000mph you will just keep pace with Earth's rotation so may never see a
sunrise/sunset.



--
Posted via a free Usenet account from http://www.teranews.com

On Tue, 19 Jun 2007 04:43:43 -0400, "Newby"
wrote:


"Radium" wrote in message
roups.com...
Hi:

How fast would an airplane need to fly in order to those onboard to
notice changes in darkness/brightness of the sky -- in which the
changes in intensity are significant enough to be noticed in seconds?
E.g. if you are flying towards the darker side of the earth, you'll
notice the sky getting darker each second just by looking outside.
Pretty scary!

Earth rotates around the sun at 1,000 MPH, so the plane would need to
be flying much faster than 1KMPH. Concord planes reached around 1KMPH.

P.S. Imagine 12:00 PM brightness turning into 12:00 AM darkness in
just 1 hour!!

Imagine 12 Noon or 12 Midnight! There is no 12 PM or 12 AM.

Strictly speaking, an confusingly, noon is 12m.

If you are turned the right way in an airplane and you are near
enough, you can see the darkness of the night side.

In fact, here in Arizona where the air is clear you can actually
see the darkness approaching from the east around sunset without
being in an airplane.

More intersting to me, though is the lakc of night. We used to
fly from San Francisco to London from tie to time in the summer,
and the British Airways flight leaves SFO in the early evening.
The plane follows a great circle route, flying rather northerly
at first then flying over Canada and Greenland, thence southerly
to London. It's about an eleven hour flight. On attaining
altitude, the sun is seen about to set low off the west side of
the plane. The sun continues to be off the left side, apparently
about to set, for the rest of the trip, until arriving in England
where the sun is still off the left side of the plane, but it is
now morning and the sun is rising.

--
************* DAVE HATUNEN ) *************
* Tucson Arizona, out where the cacti grow *
* My typos & mispellings are intentional copyright traps *

Newby writes:

Imagine 12 Noon or 12 Midnight! There is no 12 PM or 12 AM.

12 PM is noon; 12 AM is midnight.

Mxsmanic wrote:

Newby writes:


Imagine 12 Noon or 12 Midnight! There is no 12 PM or 12 AM.


12 PM is noon; 12 AM is midnight.

Wow, I agree with you, for once.

Mxsmanic wrote:
12 PM is noon; 12 AM is midnight.

12:00 is noon. 00:00 is midnight.

The space station goes at about 25,000km/h. They see sunrise and sunset
once per 45 minutes. An aircraft, if it is really lucky with strong
tailwinds, may reach 1000km/h. But to get the effect, it would need to
travel straight east.

Another way to quicken sunset would be to travel north east on december
21 in northern hemisphere (north of 45° latitude).

On Tue, 19 Jun 2007 21:59:53 -0700, NotABushSupporter
wrote:

Mxsmanic wrote:

Newby writes:


Imagine 12 Noon or 12 Midnight! There is no 12 PM or 12 AM.


12 PM is noon; 12 AM is midnight.

Wow, I agree with you, for once.

Unfortunately, Mixi is wrong. Noon is 12m, "m" being short for
"meridien", which means "noon". It is neither ante- nor post-
meridien and is simply meridien, or the time when the sun crosses
the meridian (which means "noon line").

Obviously, this gets confusing since everyone wants "m" to mean
midnight, and its a good idea to avoid it and simply use 12n for
noon.

--
************* DAVE HATUNEN ) *************
* Tucson Arizona, out where the cacti grow *
* My typos & mispellings are intentional copyright traps *

On Wed, 20 Jun 2007 06:31:46 -0400, Nobody
wrote:

Mxsmanic wrote:
12 PM is noon; 12 AM is midnight.

12:00 is noon. 00:00 is midnight.

The space station goes at about 25,000km/h. They see sunrise and sunset
once per 45 minutes.

Since the orbit time for a satellite in reasonably low earth
orbit is about 89 minutes, they see sunrise OR sunset once per 45
minutes.


--
************* DAVE HATUNEN ) *************
* Tucson Arizona, out where the cacti grow *
* My typos & mispellings are intentional copyright traps *