SpaceWatchtower

Monday, June 19, 2023

Summer Begins Mid-Day Wednesday at Solstice

[Graphic Source: © Copyright 2005, Eric G. Canali, former Floor Operations Manager of the original Buhl Planetarium and Institute of Popular Science (a.k.a. Buhl Science Center - America's fifth major planetarium and Pittsburgh's science and technology museum from 1939 to 1991), and Founder of the South Hills Backyard Astronomers amateur astronomy club; permission granted for only non-profit use with credit to author.]

By Glenn A. Walsh

Reporting for SpaceWatchtower

Late Wednesday morning, Summer begins in the Northern Hemisphere of Earth, while at the same time, Winter begins in the Southern Hemisphere.

For A.D. 2023, the season of Summer begins at Earth's Northern Hemisphere's Summer Solstice (and the season of Winter begins at the Southern Hemisphere's Winter Solstice) at the moment of the June Solstice: Wednesday Morning, 2023 June 21 at 10:58 a.m. Eastern Daylight Saving Time (EDT) / 14:58 Coordinated Universal Time [UTC – International time used by scientists; previously referred to as Greenwich Mean Time (GMT) or Greenwich Civil Time (GCT)]. Summer will continue until the Autumnal Equinox when the season of Autumn / Fall commences: Saturday Morning, 2023 September 23 at 2:50 a.m. EDT / 6:50 UTC.

In Meteorology (Weather Science), the convention is to start a season on the first day of a calendar month. So, Meteorological Summer runs from June 1 to August 31.

In Etymology, the word Solstice comes from the Latin terms Sol (Sun) and Sistere (to stand still). In ancient times, Astronomers / Astrologers / Priests recognized that on one day of the year (in the Northern Hemisphere, on or near the day we now call June 21), the Sun would appear to stand-still as Sol reaches its highest point in the sky for the entire year. The motion of the Sun's apparent path in the sky (what is known astronomically, today, as the Sun's Declination) would cease on this day, before appearing to reverse direction.

Although the Summer months in the Northern Hemisphere are known for the year's warmest weather, the Earth is actually at the point in its orbit farthest from the Sun (astronomically known as the point of Aphelion) around July 5. The Earth's closest approach to the Sun (Perihelion) each year is around January 2. Hence, in general, the distance from the Earth to the Sun is not the major factor determining the heat of Summer or the cold of Winter.

This year, Earth Aphelion will occur on Thursday Afternoon, 2023 July 6 at 4:00 p.m. EDT / 20:00 UTC. At that moment, Earth will be the farthest from the Sun for the whole year: 94,506,364.705 statute miles / 152,093,251 kilometers.

However, because Earth is farther from the Sun during our Spring and Summer seasons, people in Earth's Northern Hemisphere actually benefit from a few extra days of warmth (on average), than the number of days in the Autumn and Winter seasons of the year. When Earth is closer to the Sun, the Earth travels faster in its elliptical orbit around the Sun (during the Autumn and Winter months); and, when Earth is farther than average from the Sun (during the Spring and Summer seasons) the Earth travels a little more slowly --- again, this refers to the Northern Hemisphere. Hence, the Spring and Summer seasons, in the Northern Hemisphere, have a few more days than the Autumn and Winter seasons.

In fact, Jay Pasachoff, Field Memorial Professor of Astronomy at Williams College in Williamstown, Massachusetts and author of widely-used, college astronomy text-books, has precisely calculated the duration of each season, in the Northern Hemisphere:

* Summer: 93 days, 15 hours

* Spring: 92 days, 19 hours

* Autumn / Fall: 89 days, 20 hours

* Winter: 89 days, 0 hours

Solar radiation, and hence the heat from the Sun, depends on the length of daylight and the angle of the Sun above the horizon. The tilt of the planet's axis toward the Sun determines the additional and more direct solar radiation received by a planet's Northern or Southern Hemisphere, and hence, the warmer season of the respective hemisphere.

While the Sun does have motions (the Sun rotates on its own axis about once every 27 Earth days; our Solar System revolves around the center of the Milky Way Galaxy once every 225 million-to-250 million Earth years), it is actually the motion of the Earth tilted on its axis, away from the plane of the ecliptic (Earth's orbital plane around the Sun), while revolving around the Sun, that causes the Earth's seasons.

As of Noon today (June 19), Earth's Axial Tilt or Mean Obliquity: 23.43623° or 23°26'10.4".

Hence, as the Earth arrives at the point in its orbit around the Sun, when the north polar axis is most directly inclined toward the Sun, this marks the Summer Solstice in the Northern Hemisphere and the Winter Solstice in the Southern Hemisphere.

Alternately, the Winter Solstice in the Northern Hemisphere (the Winter Solstice is always on or near, what we now refer to as, December 21) occurs when the Earth reaches the point in its orbit when the North Pole is most directly inclined away from the Sun (and, the South Pole is most directly inclined toward the Sun). And, conversely, at this time Summer begins in the planet's Southern Hemisphere.

For Earth observers at precisely 23°26′10.9″ / 23.43637° North Latitude at the moment of the June Solstice, the Sun will appear to shine directly overhead. The line around the Earth at 23°26'10.9″ / 23.43637° North Latitude is known as the Tropic of Cancer (a.k.a. Northern Tropic). Likewise, at 23°26′10.9″ / 23.43637°) South Latitude is located the Tropic of Capricorn (a.k.a. Southern Tropic), where the Sun appears directly overhead at the moment of the December Solstice.

However, as the tilt of the Earth is dynamic, and changes minutely over the years, the location of the Tropic lines also change. Currently, these Tropic lines are moving north at the rate of 0.47 arc-seconds / 49.21 feet / 15 meters per year.

The names Tropic of Cancer and Tropic of Capricorn were coined in the last centuries B.C., when the Sun would appear in the Constellation Cancer the Crab on the June Solstice and in the Constellation Capricornus the Horned Goat on the December Solstice. However today, hours after the June Solstice, the Sun enters the Constellation Gemini the Twins, 30 degrees from Cancer. And at the December Solstice, the Sun is now in the Constellation Sagittarius the Archer.

This is due to “Precession of the Equinoxes” of Earth, which is analogous to the wobbling of a spinning top. In the case of the Earth, this 25,772-year wobble causes observers to view the Sun in different parts of the sky over the centuries, at the same time of year while remaining in the same geographical location. As the Earth wobbles over the centuries, the North Pole Star also changes. Currently, Polaris is our North Pole Star; around A.D. 13,700, Vega will be our North Pole Star, due to the Precession of the Equinoxes.

No matter which hemisphere, the day of the Summer Solstice always has the most hours and minutes of daylight (the length of time between Sunrise and Sunset) for the year, while the Winter Solstice always has the least number of hours and minutes of daylight for the year. The exact number of hours and minutes of daylight, for a particular location, depends on the locale's geographic Latitude on the Earth. Astronomers, amateur ("ham") radio operators, and long-distance radio enthusiasts (“radio DXers”), all of whom mostly depend on non-daylight hours to ply their craft, often prefer the days closer to the Winter Solstice.

The Vernal Equinox, when the season of Spring begins in the Northern Hemisphere (and the season of Autumn begins in the Southern Hemisphere), occurs between the Winter and Summer Solstices when the Earth reaches the point in its orbit around the Sun when the Earth's axis is inclined neither toward nor away from the Sun. Likewise, when the Earth reaches the point in its orbit around the Sun, between the Summer and Winter Solstices, when the Earth's axis is inclined neither toward nor away from the Sun, this is known as the Autumnal Equinox (beginning of Fall or Autumn) in the Northern Hemisphere; at this time Spring begins in the Southern Hemisphere. And, half-way between the beginning points of each season are Cross-Quarter Days, each related to traditional holidays: Groundhog Day (February 2), May Day (May 1), Lammas Day (traditionally, the first harvest festival of the year on August 1), and Halloween (October 31).

In ancient times, the Summer Solstice was known as Mid-Summer Day, in early calendars observed around June 24. At that time, May 1 to August 1 (i.e. the two Cross-Quarter Days) was considered the season of Summer. Such early European celebrations were pre-Christian in origin. Many will associate this ancient holiday with the famous William Shakespeare play, “A Midsummer Night's Dream.” Some speculate that the play was written for the Queen of England, to celebrate the Feast Day of Saint John.

As with the Roman Catholic Church's decision to Christianize the pagan Winter Solstice festivals with the introduction of Christmas Day on December 25 (by an early calendar, December 25 was reckoned as the Winter Solstice), the Church began to associate the Mid-Summer festivals with the Nativity of Saint John the Baptist on June 24. In the Christian Bible, the Gospel of Saint Luke implies that Saint John was born six months before the birth of Jesus, although no specific birth dates are given.

The most famous celebration of the Summer Solstice occurs each year at the Stonehenge pre-historic monument in England. Constructed between 3,000 B.C. and 1,600 B.C. in three phases, the actual purpose of the landmark is still unclear. However, it seems to have been associated with burials, originally. It was also used as a type of astronomical observatory, particularly for observing the Sun, which was important to help early cultures make annual decisions regarding agriculture.

Stonehenge is known as a way for pre-historic peoples to mark both the Summer and Winter Solstices. From inside the monument, a viewer facing northeast can watch the Sun rise (weather-permitting) above a stone outside the main circle of rocks, known as the Heel Stone, on the day of the Summer Solstice in the Northern Hemisphere. Although today, due to serious erosion of the stones, visitors on the Summer Solstice can only walk around the landmark from a short distance away during this annual event.

Although not as prominent as Stonehenge, a calendar ring using smaller rocks was also constructed at Nabta Playa in southern Egypt, perhaps as early as 7,000 years ago! As with Stonehenge, some stones aligned with Sunrise on the day of the Summer Solstice.

Today, a Stonehenge-like event occurs each year at the University of Wyoming (UW) Art Museum in Laramie, Wyoming, free-of-charge to the general public. At 12:00 Noon Mountain Daylight Saving Time (MDT) / 2:00 p.m. EDT / 18:00 UTC on the day of the Summer Solstice, visitors can see a single beam of sunlight shine through a solar tube in the ceiling of the UW Art Museum's Rotunda Gallery; the beam of sunlight then shines onto a 1923 Peace Silver Dollar embedded in the floor of the Museum's Rotunda Gallery. Visitors are encouraged to arrive at the museum by 11:30 a.m. MDT / 1:30 p.m. EDT / 17:30 UTC, to view this rather unique architectural feature.

The bright Star Spica (Alpha Virginis), the brightest star in the Constellation Virgo the Virgin and the 16^th brightest star in Earth's night sky (Apparent Visual Magnitude: + 0.97), may have helped develop another one of civilization's early calendars. A calendar of ancient Armenia used the year's first sighting of Spica in the dawn sky, a few days before the Summer Solstice, to mark the beginning of the New Year for this particular calendar. The development of this calendar somewhat coincided with the beginning of agriculture in Armenia.

Like clock-work, a well-known asterism (pattern of stars in the sky, not officially recognized as a constellation) of three stars shaped as a triangle is visible nearly overhead around local midnight during the Summer months (weather-permitting). And logically, as Star Trek's Mr. Spock might say, this asterism is known as the Summer Triangle!

Three of the brightest stars in the Summer sky constitute the Summer Triangle ---

Vega (Alpha Lyrae - brightest star in the Constellation Lyra the Harp); brightest of the three stars and closest to the zenith (highest point in the sky);
Altair (Alpha Aquilae - denotes the eagle eye and brightest star in the Constellation Aquila the Eagle); second brightest star of the trio;
Deneb (Alpha Cygni - denotes the tail star, is the brightest star in the Constellation Cygnus the Swan, and is the “head” star of the asterism known as the Northern Cross).

The term Summer Triangle was popularized in the 1950s by American author H.A. Rey and British astronomer Patrick Moore, although constellation guidebooks mention this triangle of stars as far back as 1913. And, during World War II, military navigators referred to this asterism as the “Navigator's Triangle.”

Regardless of city light pollution, the three bright stars of the Summer Triangle should be visible to nearly everyone in Earth's Northern Hemisphere (weather-permitting). So, just look overhead late-evening or early-morning throughout the Summer for these annual visitors to our Summer sky!

Internet Links to Additional Information ---

Source: Glenn A. Walsh Reporting for SpaceWatchtower, a project of Friends of the Zeiss

Monday, 2023 June 19.

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gaw

Glenn A. Walsh, Informal Science Educator & Communicator (For more than 50 years! - Since Monday Morning, 1972 June 12):
Link >>> http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/
Electronic Mail: < gawalsh@planetarium.cc >
Project Director, Friends of the Zeiss: Link >>> http://buhlplanetarium.tripod.com/fotz/
SpaceWatchtower Editor / Author: Link >>> http://spacewatchtower.blogspot.com/
Formerly Astronomical Observatory Coordinator & Planetarium Lecturer, original Buhl Planetarium & Institute of Popular Science (a.k.a. Buhl Science Center), America's fifth major planetarium and Pittsburgh's science & technology museum from 1939 to 1991.
Formerly Trustee, Andrew Carnegie Free Library and Music Hall, Pittsburgh suburb of Carnegie, Pennsylvania, the fourth of only five libraries where both construction and endowment funded by famous industrialist & philanthropist Andrew Carnegie.
Author of History Web Sites on the Internet --
* Buhl Planetarium, Pittsburgh: Link >>> http://www.planetarium.cc Buhl Observatory: Link >>> http://spacewatchtower.blogspot.com/2016/11/75th-anniversary-americas-5th-public.html
* Adler Planetarium, Chicago: Link >>> http://adlerplanetarium.tripod.com
* Astronomer, Educator, Optician John A. Brashear: Link >>> http://johnbrashear.tripod.com
* Andrew Carnegie & Carnegie Libraries: Link >>> http://www.andrewcarnegie.cc

* Other Walsh-Authored Blog & Web-Sites: Link >>> https://buhlplanetarium.tripod.com/gawweb.html

Wednesday, June 14, 2023

Add Your Name to Poem to be Launched to Jupiter Moon Europa

Europa, one of the first two moons of Jupiter to be discovered by famous astronomer Galileo Galilei. This image is in natural color.

(Image Sources: NASA, Jet Propulsion Laboratory, Wikipedia.org, By NASA/JPL-Caltech/SwRI/MSSS/Kevin M. Gill - File:Europa - PJ45-2.png from https://www.missionjuno.swri.edu/junocam/processing?id=13844, CC BY 3.0, https://commons.wikimedia.org/w/index.php?curid=125306643)

By Glenn A. Walsh

Reporting for SpaceWatchtower

NASA is inviting everyone to add their name to a poem that will be launched aboard the Europa Clipper, the latest U.S. unmanned spacecraft which will study Jupiter's icy moon Europa. Etched on the probe as a “Message In A Bottle” will be the poem, "In Praise of Mystery: A Poem for Europa", written by U.S. Poet Laureate Ada Limon (Internet link to the poem transcript near the end of this blog-post).

The Europa Clipper is scheduled to launch from NASA's Kennedy Space Center (Launch Complex 39A) in Florida in mid-to-late October of next year. The tentative launch date is 2024 October 10 (with a 21-day launch window until October 30), with orbital insertion expected 2030 April 11. To reach Europa, the spacecraft will travel 1.8 billion miles / 2.89 billion kilometers.

To add your name to a microchip which will be included on the spacecraft, you must register at the special NASA Internet web-site by 11:59 p.m. Eastern Standard Time (EST) on Sunday, 2023 December 31 / 4:59 Coordinated Universal Time (UTC) on Monday, 2024 January 1. Internet link to NASA web-site for public registration of names on the Europa Clipper can be found near the end of this blog-post.

One of 95 confirmed moons or natural satellites orbiting Jupiter, Europa was one of the first of two moons discovered circling another planet. It was famous astronomer Galileo Galilei who spotted Europa, along with Jupiter moon Io, on 1610 January 8.

It was also observed about the same time by German astronomer Simon Marius, which led to a dispute regarding who was the true discoverer. Although Marius did not report his discovery until a day after Galileo reported the discovery, Marius actually gave the mythological names to the four Galilean Moons. The moon Europa is named after Europa, a Phoenician noblewoman in Greek mythology, daughter of the King of Tyre.

Discovery of Europa and Io, along with Jupiter moons Callisto and Ganymede a few days later (these four moons are known as the Galilean Moons), was a monumental discovery, proving that some planetary objects orbited other planets besides the Earth. This definitively illustrated that the Copernican model of the Solar System is the correct model.

Galileo made this discovery at the University of Padua in Italy. He used the first astronomical refracting telescope, of a 20-power magnification.

Europa is the sixth closest moon to Jupiter, the sixth largest moon in the Solar System, and the smallest of the four Galilean Moons. Europa is just a little smaller than Earth's Moon.

Europa is composed of silicate rock and an iron-nickel core with a water-ice crust and a very thin atmosphere made-up mostly of Oxygen (O2). With the smoothest surface of any solid object in the Solar System, the hypothesis is that Europa has a sub-ice liquid ocean, which could harbor extraterrestrial life.

Tidal Heating, from close proximity to the largest planet in the Solar System, is thought to keep the sub-surface ocean in a liquid state. Eruptions of water vapor plumes, similar to those seen on Saturn's moon Enceladus, have been observed on Europa by the Hubble Space Telescope and the Galileo space probe. It is thought that probes to Europa can sample water from these plumes for composition and possible life, without having to land on the surface and drill into the ice sheet.

The Europa Clipper is not designed to orbit Europa. Scientists have determined this would be too dangerous due to the strong radiation belts emanating from Jupiter which could seriously damage equipment systems on-board the spacecraft.

Instead, the Europa Clipper will enter a very elliptical orbit around Jupiter, which brings the spacecraft close to Europa at a certain portion of the orbit. The Europa Clipper is scheduled to make 44 close fly-bys of the surface of the planetary body. This will allow the space probe to make scientific measurements and observations, while giving it more time to send the data back to Earth during the greater length of time when the radiation belts are not affecting the equipment.

Originally scheduled to launch aboard a NASA Space Launch System (SLS) super heavy-lift rocket (the same rocket set to send astronauts back to the Moon this decade), NASA received permission from the U.S. Congress to use a commercial launch vehicle instead. So, a SpaceX Falcon Heavy rocket will launch the Europa Clipper. The 5.5-year trajectory to the Jovian system will include two gravity-assist maneuvers to provide greater energy for the long trek: with Mars in February of 2025 and with Earth in December of 2026.

The goals of the Europa Clipper mission are to determine if Europa could be inhabited by extraterrestrial life and to scout for appropriate landing sites for a future Europa landing space probe. While examining the water plumes for possible life, scientists will be looking specifically for the three main requirements of life: liquid water (H2O), appropriate chemistry, and energy.

The three objectives scientists will be studying during this mission ---

Ice Shell and confirmation that a sub-surface ocean exists;
Ocean composition;
Geology and characteristics of surface features.

Internet Link to Poem, "In Praise of Mystery: A Poem for Europa":

Link >>> https://www.loc.gov/programs/poetry-and-literature/poet-laureate/poet-laureate-projects/a-poem-for-europa/

Internet Link to “Message In A Bottle” Public Registration for the Poem, "In Praise of Mystery: A Poem for Europa" on NASA's Europa Clipper spacecraft:

Link >>> https://europa.nasa.gov/message-in-a-bottle/sign-on/

Internet Links to Additional Information ---

Jupiter Moon Europa: Link >>> https://en.wikipedia.org/wiki/Europa_(moon)

Europa Clipper Space Probe -

Link 1 (NASA) >>> https://www.jpl.nasa.gov/missions/europa-clipper

Link 2 >>> https://en.wikipedia.org/wiki/Europa_Clipper

Tidal Heating: Link >>> https://en.wikipedia.org/wiki/Tidal_heating

Galileo Galilei: Link >>> https://en.wikipedia.org/wiki/Galileo_Galilei

Simon Marius: Link >>> https://en.wikipedia.org/wiki/Simon_Marius

More Poetry Regarding Astronomy & the Space Sciences:

Link >>> https://buhlplanetarium.tripod.com/poetry/

Related Blog-Posts ---

"Laser-Powered Sub to Explore Jupiter Moon Europa ?" Sun., 2018 Oct. 7.

Link >>> http://spacewatchtower.blogspot.com/2018/10/laser-powered-sub-to-explore-jupiter.html

"Deadline to Add Name to NASA Mars Lander: Tuesday Night." Sun., 2015 Sept. 6.

Link >>> http://spacewatchtower.blogspot.com/2015/09/deadline-to-add-name-to-nasa-mars.html

Source: Glenn A. Walsh Reporting for SpaceWatchtower, a project of Friends of the Zeiss

Tuesday, 2023 June 14.

* Other Walsh-Authored Blog & Web-Sites: Link >>> https://buhlplanetarium.tripod.com/gawweb.html

Monday, June 5, 2023

NASA Laser Com-Link Doubles Satellite Data Speed

Artist's rendering of a NASA laser communications link aboard the International Space Station. (Image Sources: NASA, Jet Propulsion Laboratory, Wikipedia.org, By NASA/Jet Propulsion Laboratory - NASA's OPALS to Beam Data From Space Via Laser, Public Domain, https://commons.wikimedia.org/w/index.php?curid=33293907)

By Glenn A. Walsh

Reporting for SpaceWatchtower

NASA, the Massachusetts Institute of Technology (MIT) and other institutions have doubled the rate of data down-loads from an Earth satellite launched last year. A space laser now allows data from the satellite to be received at a rate of 200 gigabytes per second, which doubles the rate of 100 gigabytes per second reached last year.

For the advance of scientific research, Jason Mitchell, an aerospace engineer with NASA's Space Communications and Navigation Program, says of the new milestone “more data means more discoveries”.

During a satellite's typical 5-minute pass overhead, the new data rate will allow the transmission of more than 2 terabytes of data. This is the equivalent of 1,000 high-definition motion pictures.

Within a month of reaching orbit in June of 2022, the laser com-link reached 100 gigabytes per second which is 100 times faster than Internet speeds using fiber optics in most cities and more than 1,000 times faster than traditional satellite radio data speeds.

This advancement comes from the TeraByte InfraRed Delivery (TBIRD) System, which was launched into Earth orbit in May of last year on NASA's Pathfinder Technology Demonstrator 3 (PTD-3) satellite, which uses an infrared laser. TBIRD and PTD-3 were launched from the Cape Canaveral Space Force Station in Florida on 2022 May 25, via SpaceX's Transporter-5 launch vehicle.

The PTD-3 satellite is a ~26.45-pound / 12-kilogram Cube-Sat. The satellite is described as the size of 2 cereal boxes stacked on top of each other. TBIRD is just the size of a tissue box.

This new laser communications system should help with data coming from experiments on the International Space Station (ISS). Currently, much of this data must be returned to Earth via storage drives on cargo spacecraft, due to limitations on down-link rates. TBIRD can particularly help with data regarding Earth climate and resources, as well as astronomy and astrophysics data.

One problem that scientists had to overcome was the technical problems of laser communications. Laser beams tend to distort when traveling from space, due to atmospheric effects and weather conditions. This can cause power loss and data loss.

Scientists have developed an “Automatic Repeat Request” (ARQ) protocol to control the data transmission. A low data rate up-link signal from the ground station alerts the satellite to re-transmit a certain block of data. To increase efficiency, the protocol lets the satellite know which specific data blocks need to be re-sent, so the whole transmission does not have to be repeated.

Another problem with laser beams is their tendency to form narrower beams than radio signals. TBIRD provides the satellite with the proper orientation information, so the laser beam is directed to a specific ground station.

TBIRD can support multiple channels through wavelength separation. This is how TBIRD reached 200 gigabytes per second by using two 100 gigabytes per second channels.

This new laser communications technology can have several new applications:

Imaging Black Holes with the Event Horizon Telescope;
Satellites in geostationary orbit;
Missions to the Moon and eventually Mars and other Solar System destinations;
Atmospheric data links: building-to-building and mountaintop-to mountaintop (where the laying of fiber optic cable is not feasible due to technical or financial reasons).

Internet Links to Additional Information ---

Laser Communication in Space:

Link >>> https://en.wikipedia.org/wiki/Laser_communication_in_space

NASA News Release - TeraByte InfraRed Delivery (TBIRD) System:

Link >>> https://www.nasa.gov/feature/goddard/2022/cubesat-set-to-demonstrate-nasas-fastest-laser-link-from-space

MIT TeraByte InfraRed Delivery (TBIRD) System:

Link >>> https://www.ll.mit.edu/sites/default/files/other/doc/2023-02/TVO_Technology_Highlight_12_TBird.pdf

NASA Pathfinder Technology Demonstrator:

Link>>> https://www.nasa.gov/directorates/spacetech/small_spacecraft/Pathfinder_Technology_Demonstrator/

Source: Glenn A. Walsh Reporting for SpaceWatchtower, a project of Friends of the Zeiss

Monday, 2023 June 5.

* Other Walsh-Authored Blog & Web-Sites: Link >>> https://buhlplanetarium.tripod.com/gawweb.html

Monday, May 22, 2023

Citizen Science: Help NASA 'Listen' to the Solar Wind

Image showing the Sun and Solar Wind, from the Solar and Heliospheric Observatory satellite, a joint project of NASA and the European Space Agency (ESA). (Image Sources: NASA, ESA)

_{By Glenn A. Walsh}

_{Reporting for SpaceWatchtower}

_{Help NASA 'listen' to audified
particles streaming from the Sun into Outer Space. NASA's HARP
Citizen Science Project asks volunteers to use their ears to help
scientists pick-out complex wave patterns of the Solar Wind.}

_{Outer Space is far from empty. The
Solar Wind consists of charged particles, electrons, and ions, known
as Solar Plasma, streaming every minute from the Sun, and probably
from other stars in the Universe. But, this stream of particles is
not consistent.}

_{When this Solar Wind plasma stream
hits the Earth, it causes the magnetic field lines-of-force and the
plasma around our planet “to vibrate like the plucked strings of a
harp, producing ultralow-frequency waves” according to NASA.}

_{The frequencies of the waves
scientists need to measure are too low for the human ear to hear.
HARP, the Heliophysics Audified Resonances Plasma Project, is a
NASA-sponsored Citizen Science Project which 'audifies' or makes
audible the ultra-low frequency waves caused by by the Solar Wind.
Citizen Scientists can then help scientists decipher the audible
whistles, crunches, and whooshes heard from this stream of solar
particles.}

_“_{What
excites me most about the HARP project is the ability for citizen
scientists to make new discoveries in heliophysics research through
audio analysis,” said the project’s principal investigator,
Michael Hartinger, a heliophysicist at the Space Science Institute in
Colorado, in a NASA news release. “We need their help to understand
complex patterns in the near-Earth space environment.”}

_{The
data that Citizen Scientists will use for this project comes from the
THEMIS Mission (Time History of Events and Macroscale Interactions
during Substorms), which originally consisted of five satellites
launched by NASA in 2007. As part of the THEMIS Mission, the
satellites flew through the Magnetosphere, what NASA calls Earth's
magnetic “harp”.}

_{So,
THEMIS has provided a great deal of data since 2007. However, there
is too much data for scientists to evaluate by themselves. According
to NASA, “By converting this data into sound and listening with
your ears, the brain can pick out complex wave patterns much faster
than by eye”.}

_“_{THEMIS
can sample the whole harp,” Hartinger said, “and it’s been out
there a long time, so it has collected a lot of data.”}

_{To
learn more about the NASA HARP Project, and to volunteer to
participate in the project, go to the following Internet web-site:}

_{Link
>>> https://listen.spacescience.org/}

_{Internet Links to Additional Information ---}

_{NASA News Release: "Help Discover the Sounds of Space Played by NASA's HARP."}

_{Link >>> https://www.nasa.gov/feature/goddard/2023/sun/help-discover-the-sounds-of-space-played-by-nasa-s-harp}

_{NASA THEMIS Mission: Link >>> https://en.wikipedia.org/wiki/THEMIS}

_{Solar Wind: Link >>> https://en.wikipedia.org/wiki/Solar_wind}

_{Plasma - One of Four States of Matter: Link >>> https://en.wikipedia.org/wiki/Plasma_(physics)}

Solar and Heliospheric Observatory (SoHO) Satellite:

Link >>> https://en.wikipedia.org/wiki/Solar_and_Heliospheric_Observatory

More Citizen Science Projects: Link >>> https://buhlplanetarium2.tripod.com/FAQ/citizenscience.html

Source: Glenn A. Walsh Reporting for SpaceWatchtower, a project of Friends of the Zeiss

Monday, 2023 May 22.

* Other Walsh-Authored Blog & Web-Sites: Link >>> https://buhlplanetarium.tripod.com/gawweb.html

Monday, May 1, 2023

May Day Originated in Astronomy

April showers bring May flowers !

Tulips growing in suburban Pittsburgh this Spring. (Image Source: Friends of the Zeiss; Photographer: Glenn A. Walsh)

By Glenn A. Walsh

Reporting for SpaceWatchtower

Today, May 1, marks the traditional Astronomical Cross-Quarter Day Beltane, better known as May Day.

The actual Astronomical Cross-Quarter Day date varies using the modern Gregorian Calendar. This year, the actual Beltane Cross-Quarter Day occurs on Friday, 2023 May 5 at 8:25 a.m. Eastern Daylight Saving Time (EDT) / 12:25 Coordinated Universal Time (UTC).

While using the ancient Celtic Calendar, May 1 marked the traditional Beltane Cross-Quarter Day, the Gaelic May Day Festival. This festival was widely observed in Ireland, Scotland, and the Isle of Man. In Wales, a similar celebration is known as Calan Mai.

The earliest known such Spring celebrations came during the Roman Republic era. The ancient Roman festival of Floralia (Festival of Flora, the Roman Goddess of Flowers) occurred around this time-of-year (April 27 to May 3).

The ancient Celtic Calendar divided the year into four Gaelic Festival, Quarter Days: Lady Day / Vernal Equinox (March 25), Mid-Summer Day / Summer Solstice (June 24), Michaelmas / Autumnal Equinox (September 29), and Christmas / Winter Solstice (December 25). Then, each Quarter (what we now call a Season) was divided into Cross-Quarter Days: Candlemas / Imbolc / Groundhog Day (February 2), Beltane / May Day (May 1), Lughnasadh / Lammas Day (August 1), and Samhain / Halloween (October 31).

The Celtic Calendar created Beltane, what we now call May Day, as the midway-point between the Vernal Equinox and the Summer Solstice. However, they called the Summer Solstice Mid-Summer, famous today in the name of the Shakespeare play, “A Mid-Summer Night's Dream”.

Beltane, in the Celtic Calendar, was actually considered the beginning of Summer. In ancient times, a Cross-Quarter Day was considered the beginning of a Season, while an Equinox or a Solstice was considered the midway-point in a Season.

Beltane or May Day was a day of agricultural celebration, as crops sown earlier were beginning to sprout. It also marked the time of year when cattle were moved to pastures for Summer grazing. The day marked rituals to protect the cattle, crops, and the parishioners.

It was also a day for young couples to pair-up. However, weddings would not be expected until the Mid-Summer Quarter Day. Even today, many weddings are planned for the month of June.

By the 20^th century, Beltane customs fell out-of favor. However, Celtic Neopagans and Wiccans now celebrate customs based on Beltane as a religious holiday.

In the latter part of the 19^th century, May Day became connected with the labor movement. 1889 May 1 was chosen as International Workers' Day (in some countries known as Labour Day) by the Second International to commemorate the Chicago Haymarket Riot and the struggle for an eight-hour work day.

In 1955, the Roman Catholic Church dedicated May 1 to “Saint Joseph the Worker”. Saint Joseph is considered the Patron Saint of Workers and Craftsmen, among other workers.

Completely unrelated, in the United States May 1 is also considered Law Day.

Internet Links to Additional Information ---

Beltane: Link >>> https://en.wikipedia.org/wiki/Beltane

May Day: Link >>> https://en.wikipedia.org/wiki/May_Day

International Workers' Day: Link >>> https://en.wikipedia.org/wiki/International_Workers%27_Day

Law Day: Link >>> https://en.wikipedia.org/wiki/Law_Day_(United_States)

Celtic Calendar: Link >>> https://en.wikipedia.org/wiki/Celtic_calendar

Gregorian Calendar: Link: >>> https://en.wikipedia.org/wiki/Gregorian_calendar

Related Blog-Posts ---

"Astronomy Needed to Calculate Dates of Passover & Easter." Sun., 2023 April 2.

Link >>> https://spacewatchtower.blogspot.com/2023/04/astronomy-needed-to-calculate-dates-of.html

"Spring Begins at Vernal Equinox Mon. Afternoon." Fri., 2023 March 17.

Link >>> https://spacewatchtower.blogspot.com/2023/03/spring-begins-at-vernal-equinox-mon.html

"Daylight Saving Time Returns - Year-round?" Fri., 2023 March 10.

Link >>> https://spacewatchtower.blogspot.com/2023/03/daylight-saving-time-returns-year-round.html

Source: Glenn A. Walsh Reporting for SpaceWatchtower, a project of Friends of the Zeiss

Monday, 2023 May 1.

* Other Walsh-Authored Blog & Web-Sites: Link >>> https://buhlplanetarium.tripod.com/gawweb.html

Monday, April 17, 2023

LIVE-STREAM: Rare Hybrid Solar Eclipse Early Thur. Morning

NO PARTIAL PHASE OF ANY SOLAR ECLIPSE / ECLIPSE OF THE SUN, NOR ANY ANNULAR SOLAR ECLIPSE / ANNULAR ECLIPSE OF THE SUN, IS SAFE TO LOOK AT DIRECTLY, UNLESS YOU HAVE THE PROPER TRAINING AND PROPER EQUIPMENT TO DO SO SAFELY; OTHERWISE EYE-SIGHT COULD BE DAMAGED PERMANENTLY !!! This graphic shows one way to safely view the partial phases of a Solar Eclipse / Eclipse of the Sun, or safely view an Annular Solar Eclipse / Annular Eclipse of the Sun, by building a Solar Pinhole Viewing Box (a.k.a. Pinhole Camera) as shown above. After building this box, you must turn your back to the Sun and allow the light from the Sun to go through the pinhole and shine on a white piece of paper on the other end of the inside of the box (NEVER LOOK THROUGH THE PINHOLE AT THE SUN!).
(Graphic Source: Eric G. Canali, former Floor Operations Manager of the original Buhl Planetarium and Institute of Popular Science / Buhl Science Center, America's fifth major planetarium and Pittsburgh's science and technology museum from 1939 to 1991, and Founder of the South Hills Backyard Astronomers amateur astronomy club.)

More Information - SOLAR ECLIPSE / ECLIPSE OF THE SUN: TIPS FOR SAFE VIEWING –

Link >>> https://buhlplanetarium2.tripod.com/FAQ/soleclipse/solareclipseviewingtips.html

By Glenn A. Walsh

Reporting for SpaceWatchtower

Early Thursday morning (2023 April 20), a rare Hybrid Solar Eclipse / Hybrid Eclipse of the Sun (both Total and Annular Solar Eclipse / Eclipse of the Sun) will be visible, weather-permitting, just north and west of Australia. A Live-Stream Internet Web-Cast of the event will be available for those not in the area of the eclipse, or if inclement weather prevents direct viewing of the event.

NEVER LOOK DIRECTLY AT ANY SOLAR ECLIPSE / ECLIPSE OF THE SUN, UNLESS YOU HAVE THE PROPER TRAINING AND PROPER EQUIPMENT TO DO SO SAFELY; OTHERWISE EYE-SIGHT COULD BE DAMAGED PERMANENTLY !!!

Internet link to Live-Stream Web-Cast of 2023 April 20 Hybrid Solar Eclipse / Hybrid Eclipse of the Sun near the end of this blog-post.

WHERE CAN THIS ECLIPSE BE SEEN ?

The path of the 2023 April 20 Hybrid Solar Eclipse / Hybrid Eclipse of the Sun will run from the southern portion of the Indian Ocean to just north of Australia (which will just touch the north-western tip of Australia, known as North West Cape, a remote peninsula of Western Australia). This eclipse concludes north and east of Australia. A Partial Solar Eclipse / Partial Eclipse of the Sun will be visible, weather-permitting, just beyond the confines of the Hybrid Solar Eclipse / Hybrid Eclipse of the Sun.

This eclipse will appear as a Total Solar Eclipse / Total Eclipse of the Sun in the North West Cape Peninsula and Barrow Island of Western Australia, close to the middle of the Eclipse Path. This eclipse will appear as an Annular Solar Eclipse / Annular Eclipse of the Sun. at the beginning of the Eclipse Path (at and near local Sunrise) and at the end of the Eclipse Path (at and near local Sunset).

WHEN CAN THIS ECLIPSE BE SEEN?

This rare Hybrid Solar Eclipse / Hybrid Eclipse of the Sun will be visible, weather-permitting, early on Thursday Morning, 2023 April 20. Although eclipse times will vary for specific locations, the following are the general times for this eclipse. Times are given in Coordinated Universal Time (UTC), the international time used by scientists; subtract 4 hours from the times given for Eastern Daylight Saving Time (EDT) or subtract 5 hours from the times given for Eastern Standard Time (EST). ---

First location to see Partial Eclipse begin: 1:34:26 UTC

First location to see Full Eclipse begin: 2:37:08 UTC

Time of Primary Lunar Phase of New Moon (Lunation #1241): 4:12 UTC

Greatest Eclipse: 4:16:46.8 UTC

Last location to see Full Eclipse end: 5:56:43 UTC

Last location to see Partial Eclipse end: 6:59:22 UTC

WHAT IS ---

A Solar Eclipse / Eclipse of the Sun ?

A Solar Eclipse / Eclipse of the Sun occurs when the Moon comes directly between the Sun and the Earth and part or all of the lunar shadow falls on a portion of our planet. Any Solar Eclipse / Eclipse of the Sun is dangerous to eye-sight to view directly, unless you have the proper training and proper equipment to do so safely! A Solar Eclipse / Eclipse of the Sun always occurs near and at the time of a Primary Lunar Phase of New Moon.

A Total Solar Eclipse / Total Eclipse of the Sun ?

A Total Solar Eclipse / Total Eclipse of the Sun occurs when the Path of the Eclipse includes a Path of Totality, where the Moon completely obscures the Sun for a short length of time for a particular location on the Earth which is within the Path of Totality. At the time of Totality, darkness similar to a deep level of dusk falls on that location, and sometimes scientists with special observing equipment can view Solar Flares and / or Prominences emanating from the Sun. With direct Sunlight completely blocked, the air temperature generally declines noticeably, and birds and other wildlife often begin their night-time routines.

An Annular Solar Eclipse / Annular Eclipse of the Sun ?

An Annular Solar Eclipse / Annular Eclipse of the Sun is somewhat similar to a Total Solar Eclipse / Total Eclipse of the Sun. However, unlike a Total Solar Eclipse / Total Eclipse of the Sun, the Sun is never completely covered by the Moon, for a location in the Path of Annularity, during an Annular Solar Eclipse / Annular Eclipse of the Sun. And, like during a Total Solar Eclipse / Total Eclipse of the Sun, the natural light level acts almost like at dusk, the air temperature generally declines noticeably, and birds and other wildlife are confused and may begin their night-time routines during an Annular Solar Eclipse / Annular Eclipse of the Sun.

During an Annular Solar Eclipse / Annular Eclipse of the Sun while in the Path of Annularity, the Moon blocks-out the vast majority of the Sun, except for the extremely bright edge of the solar disk. Hence, this type of eclipse is often referred to as a “Ring-of-Fire” Solar Eclipse / "Ring-of-Fire" Eclipse of the Sun, as the bright edge appears as a ring-of-fire around the dark Moon.

The reason an Annular Solar Eclipse / Annular Eclipse of the Sun does not completely block-out the Sun's light, as does a Total Solar Eclipse / Total Eclipse of the Sun, is because during an Annular Solar Eclipse / Annular Eclipse of the Sun the Moon is farther from Earth than normal and appears a little smaller as viewed from Earth. Hence, the Moon is too far, and appears too small, to block-out the entire solar disk.

A Hybrid Solar Eclipse / Hybrid Eclipse of the Sun ?

A Hybrid Solar Eclipse / Hybrid Eclipse of the Sun occurs when the eclipse begins as an Annular Solar Eclipse / Annular Eclipse of the Sun, during the middle of the Eclipse Path transitions to a Total Solar Eclipse / Total Eclipse of the Sun, then transitions back to an Annular Solar Eclipse / Annular Eclipse of the Sun as the Eclipse Path ends.

A Partial Solar Eclipse / Partial Eclipse of the Sun ?

A Partial Solar Eclipse / Partial Eclipse of the Sun occurs when only part of the Sun is blocked by the Moon. This is also true during the Partial Phases of a Total, Annular, or Hybrid Solar Eclipse / Total, Annular, or Hybrid Eclipse of the Sun. Usually, more of the Sun is still visible during a Partial Solar Eclipse / Partial Eclipse of the Sun (and during the Partial Phases of other Solar Eclipses / Eclipses of the Sun) than during an Annular Solar Eclipse / Annular Eclipse of the Sun or Hybrid Solar Eclipse / Hybrid Eclipse of the Sun.

There is no time during an Annular Solar Eclipse / Annular Eclipse of the Sun, or during a Partial Solar Eclipse / Partial Eclipse of the Sun (or during the Partial Phases any Solar Eclipse / Eclipse of the Sun), when it is safe to look directly at the eclipse, unless you have the proper training and proper equipment to do so safely!

ECLIPSE PAIRS ---

Eclipses always come in pairs, and sometimes three in-a-row. A Lunar Eclipse / Eclipse of the Moon either precedes a Solar Eclipse / Eclipse of the Sun by a couple weeks, or a Lunar Eclipse / Eclipse of the Moon follows a Solar Eclipse / Eclipse of the Sun by a couple weeks.

This time, a Penumbral Lunar Eclipse / Penumbral Eclipse of the Moon follows on Friday Afternoon, 2023 May 5. This eclipse can be viewed directly [any Lunar Eclipse / Eclipse of the Moon is safe to view with the naked-eyes (one-power), binoculars, or a telescope] from the Indian Ocean, Africa, Eastern Europe, Asia, Australia, and New Zealand. However, a Penumbral Lunar Eclipse / Penumbral Eclipse of the Moon is quite dim and often difficult to discern.

HOW TO SAFELY VIEW ANY SOLAR ECLIPSE / ECLIPSE OF THE SUN ---

Internet - Watch the eclipse on an Internet, Live-Stream Web-Cast (Internet link to Live-Stream Web-Cast near the end of this blog-post). Of course, people outside of the Path of an Eclipse can watch the eclipse on an Internet, Live-Stream Web-Cast, as well as people within the Eclipse Path where clouds obscure the view..
Public Observing Events - Sometimes educational events for eclipse viewing are sponsored by a local planetarium or science museum, astronomical observatory, science department of a local college or high school, amateur astronomy club, or local library.
Solar Pinhole Viewing Box - Create a Solar Pinhole Viewing Box (a.k.a. Pinhole Camera), as displayed and described at the beginning of this blog-post.
“Solar Eclipse Glasses” - For a few dollars you can purchase Solar Eclipse Glasses. However, only use such glasses that are specifically labeled for solar eclipse viewing, preferably approved by the American Astronomical Society (to ensure you do not purchase fake eclipse glasses). Special Note: Solar Eclipse Glasses are very fragile and must be handled gently. Also, before each use during an eclipse, check the glasses by looking through the glasses at a lit light bulb; if you find any holes or tears in the glasses, that pair of glasses could damage your eye-sight during eclipse viewing and should be discarded.
Shade Rating Number 14 Welder's Glass – Shade Rating Number 14 Welder's Glass (and only Welder's Glass Rated at Shade Number 14, the strongest shade available) can be used for safe eclipse viewing, but may be uncomfortable to some because the Sun still appears very bright through this glass.

THESE ARE THE ONLY SAFE WAYS TO VIEW ANY SOLAR ECLIPSE / ECLIPSE OF THE SUN !

INTERNET LINK TO LIVE-STREAM WEB-CAST OF 2023 APRIL 20 ECLIPSE:

Link >>> https://www.timeanddate.com/live/eclipse-solar-2023-april-20

SOLAR ECLIPSE / ECLIPSE OF THE SUN: TIPS FOR SAFE VIEWING – Link >>> https://buhlplanetarium2.tripod.com/FAQ/soleclipse/solareclipseviewingtips.html

Internet Links to Additional Information ---

Solar Eclipse: Link >>> https://en.wikipedia.org/wiki/Solar_eclipse

Hybrid Solar Eclipse: Link >>> https://en.wikipedia.org/wiki/Solar_eclipse#Types

Related Blog-Posts ---

Hybrid Solar Eclipse: 2013 Nov. 3.

Link >>> http://spacewatchtower.blogspot.com/2013/11/partial-sunrise-solar-eclipse-sunday.html

Hybrid Solar Eclipse: 2005 April 5.

Link >>> https://buhlplanetarium4.tripod.com/eclipse/hybrid2005.html

Source: Glenn A. Walsh Reporting for SpaceWatchtower, a project of Friends of the Zeiss

Monday, 2023 April 17.

* Other Walsh-Authored Blog & Web-Sites: Link >>> https://buhlplanetarium.tripod.com/gawweb.html

SpaceWatchtower

Monday, June 19, 2023

Summer Begins Mid-Day Wednesday at Solstice

Wednesday, June 14, 2023

Add Your Name to Poem to be Launched to Jupiter Moon Europa

"Laser-Powered Sub to Explore Jupiter Moon Europa ?" Sun., 2018 Oct. 7.

Link >>> http://spacewatchtower.blogspot.com/2018/10/laser-powered-sub-to-explore-jupiter.html

"Deadline to Add Name to NASA Mars Lander: Tuesday Night." Sun., 2015 Sept. 6.

Link >>> http://spacewatchtower.blogspot.com/2015/09/deadline-to-add-name-to-nasa-mars.html

Monday, June 5, 2023

NASA Laser Com-Link Doubles Satellite Data Speed

Monday, May 22, 2023

Citizen Science: Help NASA 'Listen' to the Solar Wind

Monday, May 1, 2023

May Day Originated in Astronomy

"Astronomy Needed to Calculate Dates of Passover & Easter." Sun., 2023 April 2.

Link >>> https://spacewatchtower.blogspot.com/2023/04/astronomy-needed-to-calculate-dates-of.html

"Spring Begins at Vernal Equinox Mon. Afternoon." Fri., 2023 March 17.

Link >>> https://spacewatchtower.blogspot.com/2023/03/spring-begins-at-vernal-equinox-mon.html

"Daylight Saving Time Returns - Year-round?" Fri., 2023 March 10.

Link >>> https://spacewatchtower.blogspot.com/2023/03/daylight-saving-time-returns-year-round.html

Monday, April 17, 2023

LIVE-STREAM: Rare Hybrid Solar Eclipse Early Thur. Morning

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