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Posts Tagged ‘Winter’

01/25/2022 – Ephemeris -The James Webb Space Telescope is now in orbit of Lagrange point 2 (L2)

January 25, 2022 Comments off

Note: This program was written and recorded prior to the thruster burn at 2 pm Monday, which nudged it into a halo orbit of the Earth-Sun L2 point. This post was posted after the burn.

This is Bob Moler with Ephemeris for Tuesday, January 25th. Today the Sun will be up for 9 hours and 32 minutes, setting at 5:41, and it will rise tomorrow at 8:08. The Moon, at last quarter today, will rise at 2:19 tomorrow morning.

On the James Webb Space Telescope, which should now be in a big lazy halo orbit of the Lagrangian L2, point nearly a million miles directly opposite the Sun from the Earth. Its final mid-course correction should have dropped into the halo orbit. I’m recording this Sunday night before the scheduled 2 pm yesterday mid-course correction firing. While I’m always sure it’ll be clear tonight to see the stars, or when an eclipse will happen. I’m not so sure on when or what will happen where spacecraft and rockets are involved. As far as knowing, that it will be clear tonight. I’m sure that someone will hear or read these comments, also published on my blog, and have clear skies somewhere on the planet.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). They may be different for your location.

Addendum

James Webb Space Telescope trajectory to L2

James Webb Space Telescope trajectory to L2 with some milestones of deployment. “ISIM” stands for Integrated Scientific Instruments Module. Credit: Space Telescope Science Institute (STScI).

Clouds Over Great Lakes

Lake effect clouds over Michigan. Taken earlier this month by NASA via SpaceRef.com. I live somewhere on the northwestern part of the Lower Peninsula under the lake effect clouds. We haven’t had much snow from it… Yet! But winter isn’t half over, and we can get big snow storms a month into spring. We exchange sub-zero (F) cold on the western edge of the lakes for slightly warmer temperatures, clouds and snow, until the lakes freeze, if they freeze.

03/19/2021 – Ephemeris – Enjoy this last full day of winter!

March 19, 2021 Comments off

This is Ephemeris for Friday, March 19th. Today the Sun will be up for 12 hours and 7 minutes, setting at 7:54, and it will rise tomorrow at 7:45. The Moon, 2 days before first quarter, will set at 2:23 tomorrow morning.

Spring is almost here. It will arrive at 5:37 tomorrow morning, so this is the last full day of winter, such as it was. That point in time and the point in the sky where the Sun crosses the celestial equator, the imaginary line in the sky above the Earth’s equator, heading northward is called the vernal equinox. Vernal means spring and equinox means equal night, meaning that day and night are equal, which they actually were last Tuesday. Since western civilization has spread south of the equator where the seasons are reversed, our Northern Hemisphere spring equinox is the Southern Hemisphere’s autumnal equinox, so to be understandable to both hemispheres we generally say March or September equinox instead.

Addendum

Sun's path on the equinox for TC-Interlochen

The Sun’s path through the sky on an equinox day from the Traverse City/Interlochen area in Michigan. The Sun is plotted every 15 minutes. This is a stereographic projection which compresses the sky near the zenith and enlarges the sky toward the horizon. Created using my LookingUp program.