from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. arcsecant
- n. Abbreviation of arcsecond.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. the inverse function of the secant; the angle that has a secant equal to a given number
Sorry, no etymologies found.
Fading from mag -2.6 to -2.4 and shrinking in diameter from 43 to 39 arcsec during the month, it is conspicuous near the Moon on the 2nd and again on the 30th.
Mars, slow-moving below Leo's hindquarters, doubles in brightness from mag 0.2 to -0.6 as its distance plummets from 156 million to 119 million km and its diameter swells to 12 arcsec.
Catch it 6° below-left of the earthlit crescent Moon on the 26th when its gibbous disc is 15 arcsec across.
Its cloud-banded disc is 37 arcsec wide at mid-month.
During February, it brightens from mag -4.1 to -4.2 and its gibbous disc swells from 15 to 18 arcsec.
Moving westwards below Leo's rear, it brightens from mag -0.6 to -1.2 and improves from 12 to 14 arcsec in diameter.
Look for the Moon below Saturn and alongside Spica on the 14th when a telescope shows the planet's disc and rings to be 19 and 42 arcsec wide respectively.
At opposition, Jupiter is 594 million km distant and shows a cloud-banded 50 arcsec disc through almost any telescope.
Through a telescope, its phase changes between 28% and 76% sunlit as its diameter shrinks from 8.5 to 5.9 arcsec.
Jupiter's disc is 47 arcsec wide when the planet lies alongside the Moon on the night of the 16th.
Wordnik is becoming a not-for-profit! Read our announcement here.