AkaSci 🛰️
XKCD comic pointing out that that the difference between 91% (or even a 99%) eclipse and a total eclipse is extremely dramatic. An almost total eclipse is barely noticeable, while a total eclipse is a visual phenomenon unlike any other.
https://xkcd.com/2914/
https://www.explainxkcd.com/wiki/index.php/Main_Page
1/n
AkaSci 🛰️
This is a prediction of how dramatic the total solar eclipse of April 8 will look like if you are lucky or prepared enough to be in the path of totality.
😲
This image is from a website run by Predictive Science Inc, that uses a "Data-Assimilative, Continuously Running Prediction Model" to create these images, which takes the changing magnetic field around the Sun into account in real-time.
Børge
@AkaSci That looks familiar
AkaSci 🛰️
It is E-Day!
Here is the weather forecast and forecast for cloud cover in the path of the total eclipse and the rest of the country.
Please see the rest of this thread for interesting bits of info about this eclipse and eclipses in general.
Happy viewing 😎
14/n
AkaSci 🛰️
You can follow the progress of the NASA WB-57 aircraft at https://www.flightaware.com/live/flight/N926NA and https://www.flightaware.com/live/flight/NASA927
Tail numbers N926NA and N927NA
N926NA took off from Houston (Ellington Field) at 09:57 CDT, heading SW and is currently just off the Mexican west coast at 50,000 feet altitude. It will soon turn around and track the eclipse.
Similarly for N927NA, which took off from El Paso, TX.
15/n
AkaSci 🛰️
Here is the famous painting by space artist Pat Rawlings made in 1989, showing the total solar eclipse of 2017 as seen by humans on the moon.
Well, humans have not set foot on the moon yet since the Apollo missions, but hopefully soon ...
https://twitter.com/Patnspace/status/897632376758685698
http://www.patrawlings.com/default.cfm
13/n
AkaSci 🛰️
The NASA APEP mission name takes inspiration from the serpent deity Apep from ancient Egyptian mythology, aka "the Lord of Chaos". Apep is the enemy of the Sun deity Ra and is said to have pursued him and, every so often, nearly consumed him, resulting in an eclipse.
Image below: Ra, in the form of a cat, smiting Apep with a knife. Papyrus of Hunefer, 19th dynasty.
https://sites.erau.edu/sail/APEP/
https://en.wikipedia.org/wiki/Apep
11/n
AkaSci 🛰️
Here is a look at the positions of the Sun and the Moon today, tomorrow and Tuesday, around 3:00 p.m. EDT.
https://www.timeanddate.com/worldclock/sunearth.html?iso=20240407T1504&n=105
12/n
AkaSci 🛰️
Total eclipses occur more often in the northern hemisphere than the southern one because -
- Eclipses are more likely in summer, because the Sun is up longer then.
- Summer in the northern hemisphere happens when the Earth is near aphelion, its farthest distance from the Sun for the year, the Sun is a bit smaller in the sky, which favors the occurrence of total solar eclipses and disfavors annular ones.
- The opposite holds for the southern hemisphere.
AkaSci 🛰️
The following graphic shows a heatmap of the density of total solar eclipse paths over Earth during the 5000-year period between 2,000 BCE and 3,000 CE. Lighter shades mean higher density.
The bias towards the northern hemisphere is clear. The values for longitude points are slightly smeared because the graph has not been corrected for the variance in rotational speed of the Earth.
On average, a given spot on Earth experiences a total eclipse every 366 years.
AkaSci 🛰️
In addition to the WB-57 aircraft based observations, the NASA Atmospheric Perturbations around Eclipse Path (APEP) campaign will use sounding rockets to study the ionosphere during the eclipse.
3 sounding rockets will be launched from Wallops Island, VA - 45 minutes before, during, and 45 minutes after the peak local eclipse.
4 independent payloads will be deployed by each rocket at 107 km, which will climb to 325 km, taking msmts on the way up and down to 70 km.
AkaSci 🛰️
For those who love to watch planes, here is a video from 2015 with all three of NASA's WB-57 aircraft flying in formation over Houston. This flight was the first time that three WB-57s have been aloft simultaneously since the early 1970s, when the U.S. Air Force had an active squadron of WB-57s.
https://www.youtube.com/watch?v=TvmVTzN8exQ
7/n
AkaSci 🛰️
Did you know that total eclipses occur more often in the northern hemisphere than the southern one? Or that annular eclipses occur more often at 50°S to 80°S than the equator?
This paper from 1982 shows the frequency of total and annular eclipses, as a function of latitude, between 1700 and 2299 AD. The data is based on calculations at various discrete latitude and longitude points on earth.
See the next post for the explanation.
https://articles.adsabs.harvard.edu/pdf/1982JBAA...92..124M
8/n
AkaSci 🛰️
Eclipse chasing, NASA style!
A trio of NASA-funded teams will be chasing the eclipse on April 8, with a bevy of scientific instruments onboard NASA’s WB-57 high-altitude jet planes flying at 470 mph at 50,000 feet, high above the clouds.
Looking forward to their snapshots and videos. And scientific papers.
https://www.youtube.com/watch?v=0xEDe0be6zY
https://science.nasa.gov/solar-system/skywatching/scientists-pursue-the-total-solar-eclipse-with-nasa-jet-planes/
4/n
AkaSci 🛰️
Here are a few pics of one of NASA's WB-57 aircraft.
The WB-57 is a mid-wing, long-range aircraft, developed in the 1960s, originally used by the USAF. The WB-57 can fly for ~6.5 hours, at altitudes exceeding 60,000 feet, has a range of ~2500 miles, and can carry up to 8,800 lbs of payload.
NASA's 3 WB-57s are based at Ellington Field, near Johnson Space Center (JSC) in Houston, as part of their High Altitude Research Program.
AkaSci 🛰️
Another high-altitude research aircraft that will be chasing the eclipse and gathering infra-red spectroscopy data will be NSF/NCAR's Gulfstream-V.
Inset below shows Jenna Samra, Smithsonian Astrophysical Observatory scientist, with the Airborne Coronal Emission Surveyor (ACES) instrument onboard the GV.
https://news.ucar.edu/132947/total-eclipse-celestial-wonder-and-scientific-opportunity?sf187561215=1
6/n
AkaSci 🛰️
Cloud-cover forecast from NOAA for Eclipse Day April 8, around 2 PM EDT.
Best places for clear viewing are in northern New England and upstate New York. Also, southern Missouri to central Indiana.
Peak viewing time in Evansville, IN is around 2:00 p.m. CDT (3:00 p.m. EDT).
https://www.wpc.ncep.noaa.gov/key_messages/LatestKeyMessage_2.png
3/n
AkaSci 🛰️
A real-time shot of the total solar eclipse from the NASA WB-57 aircraft from 50,000 feet off the west coast of Mexico!
😲
Watch the NASA livecast at https://www.youtube.com/watch?v=2MJY_ptQW1o
16/n
AkaSci 🛰️
These gorgeous views of the total solar eclipse of 2024 were taken from the ground in the city of Torreón in Mexico.
The Baily's beads can be prominently seen in the first pic.
NASA webcast at https://www.youtube.com/watch?v=2MJY_ptQW1o
https://en.wikipedia.org/wiki/Baily%27s_beads
17/n
GNU social JP is a social network, courtesy of GNU social JP管理人. It runs on GNU social, version 2.0.2-dev, available under the GNU Affero General Public License.
All GNU social JP content and data are available under the Creative Commons Attribution 3.0 license.
