Many Moons

Full moons during the year have many different names in many different cultures.

Most people want something in the sky to be special and unique to their lifetime on Earth. An Earth that has been here for four and a half billion years.
— Neil deGrasse Tyson

Traditional Native American names for the moons:

January	Difficulty, Black Smoke
February	Raccoon, Bare Spots on the Ground
March	Wind, Little Grass, Sore-Eye
April	Ducks, Goose-Eggs
May	Green Grass, Root-Food
June	Corn-Planting, Strawberry
July	Buffalo (Bull), Hot Sun
August	Harvest, Cow Buffalo
September	Wild Rice, Red Plum
October	Leaf-Falling, Nuts
November	Deer-Mating, Fur-Pelts
December	Wolves, Big Moon

From Earth, the full moon appears fully illuminated because it is positioned directly opposite the Sun.

Strawberry Moon
Park Point, Duluth, Minnesota, 20 June 2016
Photograph: Grant Johnson

The June full moon is called the Strawberry Moon. Because the June full moon never gets comparatively high above the horizon, nor does the Sun get comparatively low below the horizon, the Strawberry moon is characterized by its reddish to honey-colored tint from sunlight filtered through our atmosphere.

This year the Strawberry Moon coincided with the June Solstice in the northern hemisphere. A Strawberry Moon on the summer solstice hasn't happened since 1948.


REFERENCES

• Delicious 'Strawberry Moon' Photos: Rare Solstice Lunar Show Wows Stargazers, Calla Cofield, Space.com 21 June 2016.
• Neil deGrasse Tyson Explains The "Strawberry Moon", video clip from The Late Show with Stephen Colbert The Late Show with Stephen Colbert, 23 June 2016.

Platypus to Puffball

Family tree of Earth's lifeforms

A family tree of Earth's lifeforms, some 2.3 million named species thus far, was recently published in draft form on opentreeoflife.org.

The circular tree of life compiled on opentreeoflife.org traces back 3.5 billion years ago to the beginning of life on Earth.

A tree of life, or phylogenetic tree, is typically a branching diagram that resembles a tree found in nature.

The lines or branches on a phylogenetic tree represent evolutionary relationships ― from platypus to puffball.

The affinities of all the beings of the same class have sometimes been represented by a great tree. I believe this simile largely speaks the truth.
― Charles Darwin, Origin of Species, Chapter IV

Branching relationships are derived from an organism's physical or genetic characteristics. Microbiologist Carl Woese proposed the tree of life shown below based on RNA data.

Phylogenetic tree scientific names

source: Eric Gaba, NASA Astrobiology Institute

The human species falls under the kingdom of animalia (shown in brown lines above) in the eucarya branch (cf. Human Classification in Know thy Tribe).

Charles Darwin found the tree to be a suitable metaphor to represent evolutionary relationships:

"The green and budding twigs may represent existing species; and those produced during former years may represent the long succession of extinct species. At each period of growth all the growing twigs have tried to branch out on all sides, and to overtop and kill the surrounding twigs and branches, in the same manner as species and groups of species have at all times overmastered other species in the great battle for life. The limbs divided into great branches, and these into lesser and lesser branches, were themselves once, when the tree was young, budding twigs; and this connexion of the former and present buds by ramifying branches may well represent the classification of all extinct and living species in groups subordinate to groups. Of the many twigs which flourished when the tree was a mere bush, only two or three, now grown into great branches, yet survive and bear the other branches; so with the species which lived during long-past geological periods, very few have left living and modified descendants. From the first growth of the tree, many a limb and branch has decayed and dropped off; and these fallen branches of various sizes may represent those whole orders, families, and genera which have now no living representatives, and which are known to us only in a fossil state. As we here and there see a thin, straggling branch springing from a fork low down in a tree, and which by some chance has been favoured and is still alive on its summit, so we occasionally see an animal like the Ornithorhynchus or Lepidosiren, which in some small degree connects by its affinities two large branches of life, and which has apparently been saved from fatal competition by having inhabited a protected station. As buds give rise by growth to fresh buds, and these, if vigorous, branch out and overtop on all sides many a feebler branch, so by generation I believe it has been with the great Tree of Life, which fills with its dead and broken branches the crust of the earth, and covers the surface with its ever-branching and beautiful ramifications."
― Origin of Species, Chapter IV

Intelligent Life

Asked in a NOVA episode about the prospect of finding intelligent life somewhere beyond Earth's biosphere, cosmologist Neil deGrasse Tyson speculates that finding intelligent extraterrestrial life seems unlikely. Tyson draws a distinction between human intelligence ― characterized by perception, consciousness, self-awareness, and volition ― and the mechanisms needed to survive and proliferate.

I think that intelligence is such a narrow branch of the tree of life—this branch of primates we call humans. No other animal, by our definition, can be considered intelligent. So intelligence can't be all that important for survival, because there are so many animals that don't have what we call intelligence, and they're surviving just fine.
― Neil deGrasse Tyson

Life might exist beyond our life-raft in the biosphere. Tyson muses that the search for extant life is more likely to turn up "anything that falls between single-celled bacteria and life that has some kind of interesting purpose or function to perform", rather than life with the intellectual capacity of humans.


REFERENCES

• A Conversation With Neil Tyson, Nova, 28 September 2004.
• Know thy Tribe, GrokEarth, 12 September 2015.
• Origin of Species, Charles Darwin, The Harvard Classics, 1909–14.
• Phylogenetic tree, Wikipedia.
• 'Tree of life' for 2.3 million species released, Phys.org, 19 September 2015

Super Blood Moon

The confluence of three celestial phenomena happen tomorrow evening:

• a full moon;
• a supermoon; and
• a total lunar eclipse.

The last supermoon eclipse occurred in 1982.

Celestial phenomena are predictable because we have studied and understand planetary movements in the solar system.

Nothing comes close to the precision with which physics enables you to understand the world around you. It's the laws of physics that allow us to say exactly what time the sun is going to rise. What time the eclipse is going to begin. What time the eclipse is going to end.
― Neil deGrasse Tyson

Blood Moon
source: Anne Dirkse

Full moon

Tomorrow's full moon will be both a harvest moon and a blood moon.

A harvest moon is the full moon that falls closest to the fall equinox, which was last Wednesday.

A blood moons describes the red-tinted moon observed during a lunar eclipse. During a lunar eclipse, sunlight directed around the edges of the Earth refracts through Earth's atmosphere filtering out all but red, giving the moon its blood red tint.

Supermoon

Tomorrow's full moon will be a supermoon, or the full moon in perigee.

The moon orbits Earth in an elliptical path meaning that the distance between Earth and moon varies over an orbital cycle, giving us supermoons and micromoons.

A supermoon compared to a micromoon
source: Friends of NASA

Supermoons occur when the moon's orbital path transports it to the closest point to Earth. Micromoons occur when the moon is at its farthest point from Earth. A supermoon is about 31,000 miles closer to the Earth than a micromoon.

The closer proximity of a supermoon makes it appear 14% larger and 30% brighter.

The stronger gravitational pull of the supermoon causes wider variation in high and low tide levels.

Lunar Eclipse

Tomorrow's full moon will undergo a total eclipse.

Tomorrow night, the Earth will line up between the sun and the moon. The moon will gradually move into the shadow of the earth until it falls into darkness (i.e, a total eclipse).

Lunar eclipse
source: Luca

Under clear skies, tomorrow's lunar eclipse should be visible from longitudes stretching from the eastern Pacific to western Asia, including the Americans, Europe, and Africa.

Three things cannot be long hidden: the sun, the moon, and the truth.
― Gautama Buddha

The next supermoon eclipse occurs in 2033.

REFERENCES

• Rare supermoon eclipse comes Sunday, Jareen Imam, CNN, 25 September 2015.
• Super Blood Moon eclipse on night of September 27-28, Bruce McClure, EarthSky.
• Supermoon, GrokEarth, 12 July 2014.

Gravity Potato

GRACE satellite data

As mass goes, so goes gravity.

The earthward acceleration of gravity varies by about 0.5% over the surface of the Earth because of unevenly distributed mass.

Exaggerated data visualizations depict the dissymmetrical variations in Earth's gravity field.

Time and Location

Gravitational pull varies by location because of unevenly distributed mass in the oceans, continents, and deep interior. Climate-related variables, like continental water balance, and the accumulation or ablation of glaciers, causes the distribution of mass to vary over time.

Measuring G-Force

The local gravitational field is measured using a gravimeter. A gravimeter is an accelerometer that measures the earthward acceleration of gravity or G-force.

Gravity Potato

Variations in Earth's gravity field is shown in an image known as the Potsdam Gravity Potato. The Potsdam Gravity Potato is derived from a gravity field model produced by the German Research Center for Geophysics (GFZ).

Geoid: The Potsdam Gravity Potato

Some 800 million observations support GFZ's gravity field model. Supporting data were obtained from:

• LAGEOS, GRACE , and GOCE satellites;
• Ground-based gravity measurements; and
• Satellite altimetry data.

Attraction Mystery

Gravity is a natural phenomenon wherein physical bodies attract each other. Gravity gives weight to physical objects and causes objects to fall when dropped.

Because there is a law such as gravity, the universe can and will create itself from nothing.
— Stephen Hawking

Gravity is one of four fundamental forces. Gravitation acts across the universe. Earth's gravitation is part of the human experience mediating nearly everything we do.

Most gravity has no known origin. Is it some exotic particle? Nobody knows.
— Neil deGrasse Tyson

REFERENCES

• Geoid, Wikipedia.
• Geoid: The Potsdam Gravity Potato, GFZ - German Research Centre for Geosciences.
• Grounded, GrokEarth, 12 April 2014.
• The Potsdam Gravity Potato Shows Variations in Earth’s Gravity, Matt Williams, Universe Today, 29 November 2014.