18 January 2024

Because the Earth’s axis doesn’t change how it tilts as it orbits the sun, the sun is higher in the summer sky and lower in winter. Meanwhile sunrise and sunset march north and south along the horizon from solstice to solstice.

You can see both effects in this composite photo by Tunç Tezel (The World At Night) showing the sun’s path at summer solstice, equinox and winter solstice in Bursa, Turkey, embedded from NASA APOD.

In my own way I’ve kept track of the same thing. When we lived in Greenfield our house faced west so I noted where the sun set for both solstices and the equinox. Now we face east and I haven’t done that yet for sunrise, but I already have some markers.

Here’s my eastern view at sunrise yesterday morning. This can be a marker.

I also have four photos of sun pillars which are good sunrise markers.

Put together on an eastern view photo, it looks like this. You can already see the sun marching along.

I did not add yesterday’s sunrise to the marker photo because it was too close to 11 January, but the sun did indeed move northward in 6 days. See composite photo below.

I’m well on my way toward completing the sunrise markers but it will take a year to do it. I need both solstices and the equinox.

Try it for yourself. Any horizon will do even if you’re in a valley. During one year take 3 to 12 photos, either just the solstices & equinox or one photo per month. Note the date and the sun’s location on the horizon. Put the markers on your horizon photo as I have done above.

So where did the sun come up today?

Ummm … Not today in Pittsburgh. It’s too cloudy to see the sun.

3 January 2024

As I mentioned last month, though winter is the best time of year to see the aurora borealis it is rare if not impossible to see it anywhere but in the far north. The photo at top was taken in Norway while the one below gives a different perspective from an airplane at 36,000 feet above Canada.

In both cases the photos were taken inside our atmosphere below the aurora. What if you could see the aurora from above?

On 21 January 2016 NASA astronaut Scott Kelly took photos of the aurora from the International Space Station (ISS) as it traveled over Canada. Here’s what the aurora looks like from above in his series of photos.

Aurora borealis over Canada, seen from ISS on 21 Jan 2016 (photos from Wikimedia Commons)

The ISS also saw the aurora australis, the southern lights near the South Pole, in July 2012.

Want to know if there will be an aurora soon and where it will show up? Check here for NOAA’s Aurora Viewline predition for tonight and tomorrow.

28 December 2023

We usually take for granted that even on a clear night there aren’t many stars to see. When the news reminds us to watch for an astronomical event such as the Geminid meteor shower on 13 December, we realize that most of us have to drive somewhere to find a dark sky. Even rural skies show fewer stars than a dark sky site, and Dark Sky locations are getting harder to find as light pollution proliferates.

There’s a universe above us that most of us cannot see. Learn more in this vintage article:

22 December 2023

The short days of winter give us longer nights at the best time of year for viewing the northern lights.

Pittsburgh is generally too far south and always has too much light pollution from city lights for viewing the aurora borealis so let’s enjoy beautiful scenes from the arctic.

Wondering what areas are due to see the northern lights tonight or tomorrow? See NOAA’s 2-day aurora forecast maps or the 30-minute forecast for predictions of beauty in the sky.