solar eclipse of July 22, 1990
{{Short description|Total eclipse}}
{{Infobox solar eclipse|1990Jul22
| previous = Solar eclipse of January 26, 1990
| next = Solar eclipse of January 15, 1991
}}
A total solar eclipse occurred at the Moon's descending node of orbit between Saturday, July 21 and Sunday, July 22, 1990,{{cite web|title=July 22, 1990 Total Solar Eclipse|url=https://www.timeanddate.com/eclipse/solar/1990-july-22|publisher=timeanddate|access-date=9 August 2024}} with a magnitude of 1.0391. A solar eclipse occurs when the Moon passes between Earth and the Sun, thereby totally or partly obscuring the image of the Sun for a viewer on Earth. A total solar eclipse occurs when the Moon's apparent diameter is larger than the Sun's, blocking all direct sunlight, turning day into darkness. Totality occurs in a narrow path across Earth's surface, with the partial solar eclipse visible over a surrounding region thousands of kilometres wide. Occurring 2.7 days after perigee (on July 19, 1990, at 12:20 UTC), the Moon's apparent diameter was larger.{{cite web|title=Moon Distances for London, United Kingdom, England|url=https://www.timeanddate.com/astronomy/moon/distance.html?year=1990&n=136|publisher=timeanddate|access-date=9 August 2024}}
Totality was visible in southern Finland including its capital city Helsinki, the Soviet Union (including today's northern Estonia and northern Russia), and eastern Andreanof Islands and Amukta of Alaska. A partial eclipse was visible for parts of Eastern Europe, North Asia, Alaska, western Canada, the western United States, and Hawaii.
In Finland, the solar eclipse occurred during sunrise and enabled observation and photography without protective glasses, which was however hampered by strong clouds.{{Cite web |title=Sonnenfinsternis in Finnland |url=https://www.bujack.de/berichte/reise/finst.htm |access-date=2023-12-21 |website=www.bujack.de}} The Sun was totally eclipsed in Helsinki began at 06:03:07 local time.
Observations
The Finnish Geodetic Institute conducted a series of measurements for 52 hours to study the changes in gravity using an absolute gravimeter in Helsinki. No abnormal values were recorded.{{cite journal|author=Jaakko Mäkinen|title=Absolute Gravity Measurements During the July 22, 1990 Total Solar Eclipse in Finland|date=December 1990|journal=Bulletin d'Information of the Bureau Gravimétrique International|volume=67|pages=203-208|url=https://www.researchgate.net/publication/227171547_Interpretation_of_the_tidal_residuals_during_the_11_July_1991_total_solar_eclipse|archive-date=1 September 2019|archive-url=https://web.archive.org/web/20190901150206/https://www.researchgate.net/publication/227171547_Interpretation_of_the_tidal_residuals_during_the_11_July_1991_total_solar_eclipse}} An observation team of the Academy of Sciences of the Soviet Union went to the Solovetsky Islands, Arkhangelsk Oblast in the White Sea, and planned to take images of the corona with different exposure levels and record videos. However, there were clouds at sunrise on the eclipse day, and drizzle continued until noon, so the observation was not successful.{{cite web|title=СОЛНЕЧНОЕ ЗАТМЕНИЕ 22 ИЮЛЯ 1990 г. НАДЕЖДЫ И РЕАЛЬНОСТЬ|url=http://www.izmiran.ru/info/personalia/molodensky/Eclips90_r.html|publisher=IZMIRAN|language=ru|archive-date=7 September 2019|archive-url=https://web.archive.org/web/20190907045019/http://www.izmiran.ru/info/personalia/molodensky/Eclips90_r.html}}
Eclipse details
Shown below are two tables displaying details about this particular solar eclipse. The first table outlines times at which the moon's penumbra or umbra attains the specific parameter, and the second table describes various other parameters pertaining to this eclipse.{{cite web|title=Total Solar Eclipse of 1990 Jul 22|url=https://eclipsewise.com/solar/SEprime/1901-2000/SE1990Jul22Tprime.html|publisher=EclipseWise.com|access-date=9 August 2024}}
| class="wikitable" align="{{{align|left}}}" style="margin:{{#ifeq:{{{align}}}|left|0 0 0.5em 1em|0 1em 0.5em 0}}"
|+July 22, 1990 Solar Eclipse Times ! Event ! Time (UTC) |
| First Penumbral External Contact
| 1990 July 22 at 00:40:59.9 UTC |
| First Umbral External Contact
| 1990 July 22 at 01:53:08.5 UTC |
| First Central Line
| 1990 July 22 at 01:54:21.6 UTC |
| First Umbral Internal Contact
| 1990 July 22 at 01:55:35.5 UTC |
| Equatorial Conjunction
| 1990 July 22 at 02:37:42.8 UTC |
| Ecliptic Conjunction
| 1990 July 22 at 02:55:15.0 UTC |
| Greatest Duration
| 1990 July 22 at 03:00:36.7 UTC |
| Greatest Eclipse
| 1990 July 22 at 03:03:07.3 UTC |
| Last Umbral Internal Contact
| 1990 July 22 at 04:10:58.3 UTC |
| Last Central Line
| 1990 July 22 at 04:12:09.7 UTC |
| Last Umbral External Contact
| 1990 July 22 at 04:13:20.4 UTC |
| Last Penumbral External Contact
| 1990 July 22 at 05:25:30.2 UTC |
| class="wikitable" align="{{{align|right}}}" style="margin:{{#ifeq:{{{align}}}|right|0 0 0.5em 1em|0 1em 0.5em 0}}"
|+July 22, 1990 Solar Eclipse Parameters ! Parameter ! Value |
| Eclipse Magnitude
| 1.03908 |
| Eclipse Obscuration
| 1.07968 |
| Gamma
| 0.75972 |
| Sun Right Ascension
| 08h04m51.4s |
| Sun Declination
| +20°20'48.2" |
| Sun Semi-Diameter
| 15'44.5" |
| Sun Equatorial Horizontal Parallax
| 08.7" |
| Moon Right Ascension
| 08h05m49.3s |
| Moon Declination
| +21°03'44.2" |
| Moon Semi-Diameter
| 16'11.1" |
| Moon Equatorial Horizontal Parallax
| 0°59'24.2" |
| ΔT
| 57.2 s |
{{clear}}
Eclipse season
{{See also|Eclipse cycle}}
This eclipse is part of an eclipse season, a period, roughly every six months, when eclipses occur. Only two (or occasionally three) eclipse seasons occur each year, and each season lasts about 35 days and repeats just short of six months (173 days) later; thus two full eclipse seasons always occur each year. Either two or three eclipses happen each eclipse season. In the sequence below, each eclipse is separated by a fortnight.
| class="wikitable"
|+ Eclipse season of July–August 1990 ! July 22 | |
| 200px | 200px |
| align=center
| Total solar eclipse | Partial lunar eclipse Lunar Saros 138 |
Related eclipses
= Eclipses in 1990 =
- An annular solar eclipse on January 26.
- A total lunar eclipse on February 9.
- A total solar eclipse on July 22.
- A partial lunar eclipse on August 6.
= Metonic =
- Preceded by: Solar eclipse of October 3, 1986
- Followed by: Solar eclipse of May 10, 1994
= Tzolkinex =
- Preceded by: Solar eclipse of June 11, 1983
- Followed by: Solar eclipse of September 2, 1997
= Half-Saros =
- Preceded by: Lunar eclipse of July 17, 1981
- Followed by: Lunar eclipse of July 28, 1999
= Tritos =
- Preceded by: Solar eclipse of August 22, 1979
- Followed by: Solar eclipse of June 21, 2001
= Solar Saros 126 =
- Preceded by: Solar eclipse of July 10, 1972
- Followed by: Solar eclipse of August 1, 2008
= Inex =
- Preceded by: Solar eclipse of August 11, 1961
- Followed by: Solar eclipse of July 2, 2019
= Triad =
- Preceded by: Solar eclipse of September 21, 1903
- Followed by: Solar eclipse of May 22, 2077
= Solar eclipses of 1990–1992 =
{{Solar eclipse set 1990–1992}}
= Saros 126 =
{{Solar_Saros_series_126}}
= Metonic series =
{{Solar Metonic series 1971–2047}}
= Tritos series =
{{Solar Tritos series 2001 June 21}}
= Inex series =
{{Solar Inex series 2019 July 2}}
Notes
{{reflist}}
References
{{Solar eclipse NASA reference|1951/SE1990Jul22T|19900722}}
Photos:
- [http://www.zam.fme.vutbr.cz/~druck/Eclipse/Ecl1990/0-info.htm Prof. Druckmüller's eclipse photography site]
- [http://xjubier.free.fr/en/site_pages/solar_eclipses/Solar_Corona_Shape_pg03.html Druckmüller in Chukotka, Soviet Union]
- [http://www.eclipse-2008.ru/eclipse/1990.php in Russia]
- [http://www.eclipse-2008.ru/eclipse/1990a.php in Russia (2)] {{Webarchive|url=https://web.archive.org/web/20090809113845/http://eclipse-2008.ru/eclipse/1990a.php |date=2009-08-09 }}
- [http://www.izmiran.ru/info/personalia/molodensky/Eclips90_r.html Russian scientist had no successful observation of the eclipse]
{{Solar eclipses}}
{{DEFAULTSORT:Solar Eclipse Of July 22, 1990}}