WISE Shows us Infrared Views of Time and Space

The Sculptor Galaxy heats up

 

 

WISE uses four infrared detectors to view the Sculptor Galaxy

Wise takes us to the Sculptor Galaxy NGC 253 

Astronomy News – In the next leg of the human “Journey to the Beginning of Space and Time” we travel 11.4 million light years, give or take a few hundred thousand, to the Sculptor Galaxy NGC 253 (the Silver Coin Galaxy) to view an infrared mosaic of images taken by NASA’s Wide-field Infrared Survey Explorer (WISE). Part of the Sculptor group of galaxies (South Polar Group), the 7.6 magnitude Silver Coin Galaxy has infant stars in duty cocoons heating up the galaxies core and broadcasting infrared light into the universe and is the brightest member of the Sculptor group of galaxies. Young emerging stars in the infrared images shown here are concentrated in the galaxies core and along the spiral arms. The green areas are tiny dust or soot particles left after the formation of these emerging stars that have absorbed the ultraviolet light from these young stars, which makes these particles glow with infrared light the four infrared detectors on WISE can detect. The blue image on the top was taken in the short wavelengths, about 3.4 and 4.6 microns, this photo has stars of all ages scattered all over the Sculptor Galaxy. 
 
NGC 253 is considered a starburst galaxy, and an intermediary type of spiral galaxy, with stars forming and exploding at unusually high rates in an intense star-forming period. First recorded by Caroline Herschel, the sister of astronomer William Herschel, on September 23, 1783, the Sculptor Galaxy can best be seen in the Sculptor constellation in the southern night sky in late September by stargazers using a time-machine-to-the-stars. Stargazers with good eyes and a dark sky can even view NGC 253 during this time, just be prepared to spend a little time in the search for the Silver Coin Galaxy.
 

Wise continues to go forth into the unknown

Check out my newest astronomy blog at http://astronomytonight.yolasite.com/.
This is why they call NGC 253 the Silver Coin Galaxy

Learn why astronomy binoculars are a popular choice with amateur astronomers

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Dance Across the Night Sky with Cassiopeia the Queen

 
 

Stargazers Halloween treats abound in autumn’s night sky

Dance cross the night sky with Cassiopeia the Queen
This star map gives you an idea of the stars in and around Cassiopeia the Queen

Winter treat for the lonely wanderer

Astronomy news (2013-10-15) – Cassiopeia the Queen is one of the first northern deep sky objects we’ll view during our “Journey to the Beginning of Space and Time”. Cassiopeia the Queen is easily recognizable in autumn’s night sky using her characteristic W or M shape form and she was one of the 48 constellations originally listed by the 2nd-century Greek astronomer Ptolemy during his observations of the night sky. Today, Cassiopeia the Queen is one of 88 constellations recognized by modern stargazers in the night sky, and the abundance of magnificent open star clusters within her arms provides viewers with a chance to see a variety of outstanding celestial objects that have been entertaining stargazers for thousands of years.

Five stars outline Cassiopeia’s characteristic W shape

Cassiopeia the Queen is a familiar sight for modern astronomers and stargazers in the mid-northern latitudes of planet Earth and is often one of the first constellations in the northern sky beginning stargazers journey to view. Board your time-machine-to-the-stars near the end of October, or the beginning of November, and take the family on a journey through time and space to visit Cassiopeia the Queen. A visit with Cassiopeia the Queen will open a child’s mind to the possibilities of the universe, before them, and your wife will be able to tell her friends that you took her out last night.

8×50 astronomical binoculars will reveal about 12 stars nestled in among the collective glow of other stars too faint to resolve

Both astronomers and ancient navigators used Cassiopeia as a guide to finding their way

One of the best open star clusters you can view with the naked eye is 6.5 magnitude NGC 129, a large, bright, open cluster of stars 8×50 astronomical binoculars will reveal to have six to twelve brighter stars nestled within the collective glow of a field of stars too faint to resolve using binoculars. You should see about 35 celestial bodies in this region of space and time 5,200 light years distant from your position on the Earth. Look toward the north of two 9th magnitude stars, near the center of NGC 129, and you’ll find the Cepheid variable DL Cassiopeiae. DL Cassiopeiae will fluctuate between 8.6 and 9.3 magnitudes, over the course of an eight-day cycle.

The central star in Cassiopeia’s characteristic W is Gamma Cassiopeiae, a prototype for a class of irregular variable stars believed to be rapidly spinning type-B celestial bodies often fluctuating by as much as magnitude 1.5 or more, Gamma Cassiopeiae will flicker between 2.2 and 3.4 magnitudes as you watch her nightly dance and this star at maximum brightness outshines both Alpha Cassiopeiae and Beta Cassiopeiae. Astronomers believe these apparent fluctuations are due to a decretion disk around this star resulting from the rapid spinning of the star, which results in some of the star’s mass forming a decretion disk. Gamma Cassiopeiae is also a spectroscopic binary star with an orbital period of about 204 days and astronomers believe Gamma Cassiopeiae’s companion star is about the same relative mass as Sol. Part of a small group of stellar sources in the night sky that beam X-ray radiation about 10 times higher than the X-rays emitted from other type-B stars across the cosmos, Gamma Cassiopeiae exhibits both short-term and long-term cycles of x-ray emission. Stargazers should also be able to view Gamma Cassiopeiae as an optical double star, with a faint magnitude 11 companion star, about 2 arcseconds distant from Gamma Cassiopeiae.

Chinese astronomers studied Gamma Cassiopeiae

Ancient stargazers in China called Gamma Cassiopeiae Tsih, which loosely translates as “the whip”, but no references have been found in Arabic or Latin texts of Gamma Cassiopeiae being referred to using a different name. Modern stargazers refer to Gamma Cassiopeiae by a number of different designations, including 27 Cassiopeiae, HR 264, HD 5394, and others. Modern astronauts often use Gamma Cassiopeiae as a star guide because it’s a relatively bright celestial object and in previous space missions this star was used as an easily recognizable navigational reference point in the night sky.

M103 (NGC 581) will reveal about 25 magnitude 10 or fainter stars

Astronomers note two Messier objects

M103 (NGC 581) is the first of two Messier objects in Cassiopeia’s arms viewable through a six-inch time-machine-to-the-stars and should appear as about three dozen stars grouped in a triangular area 6′ across. A fairly compact open cluster, M103 will be 1 degree east of Delta Cassiopeiae, and is the left bottom star of Cassiopeia’s characteristic W shape marking her throne in the night sky. Pierre Mechain was first given credit for seeing this open cluster in the night sky in 1781. Stargazers using 8×50 binoculars will see about 25 magnitude 10 or fainter stars in their view and a string of four stars immediately to M103’s southeast, which adds to the beauty of viewing M103, significantly.

M 52 (NGC7654) is one of the richest open clusters to view north of the celestial equator

The second Messier object in Cassiopeia cataloged by Messier is M52 (NGC 7654), you can locate M52 by drawing a line from Alpha Cassiopeiae through Beta Cassiopeiae, and then extending your line an equal distance to M52. An 8-inch time-machine-to-the-stars will reveal about 75 stars in the night sky clumped in various patterns along the edge of the Milky Way that aren’t lost among the background points of light behind these stars. One of the richest open clusters in Cassiopeia’s arms and north of the celestial equator, Messier made note of M52 in his catalog in 1774. This open cluster will appear as a nebulous mass of about 100 stars in 8×50 astronomical binoculars, with a few individual stars that you can resolve a little better. Stargazers looking for a little extra should look to the north of M52 to find Harrington 12, a wide triangular looking asterism containing about a dozen 5th to 9th magnitude stars, which will appear spectacular in low-power astronomical binoculars.

The Owl spreads its wings

Journey less than 3 degrees south of Delta Cassiopeiae to find the spectacular Owl Cluster (NGC 457), a celestial object ancient stargazers could plainly see in the north night sky, the Owl Cluster’s wings will be clearly viewable using a 4-inch time-machine-to-the-stars. Stargazers can also locate Delta Cassiopeiae by using 5th magnitude Phi Cassiopeiae and 7th magnitude HD 7902, which lie to the southeast of the Owl Cluster. The Own’s eastern wing is a line of four bright stars while the western wing is composed of two pairs of stars arranged in a long rectangle. The brightest star in the Owl Cluster will shine at 8.6 magnitude and will appear a little orange in color to star gazers.

Cassiopeia the Queen reigns in autumn’s night sky

Check out my newest astronomy site at http://astronomytonight.yolasite.com/, and then let me know what you think?

Learn how NASA astronomers are planning on detecting extraterrestrial moons orbiting distant suns https://spaceshipearth1.wordpress.com/2013/12/31/searching-for-extraterrestrial-moons/.

Read about the latest news on life beyond Earth https://spaceshipearth1.wordpress.com/2013/12/25/the-search-for-life-beyond-earth-takes-a-turn-at-jupiter/.

Take a look at the latest natural color images taken by the Cassini spacecraft https://spaceshipearth1.wordpress.com/2013/12/22/cassini-spacecraft-show-views-of-the-solar-system-in-natural-color/.

Navigating the Universe Using the Stars as Your Guide

Astronomers use coordinate systems to plot the position of stars in the night sky

Astronomy questions and answers – Looking up into the night sky you probably wonder how ancient stargazers were able to navigate using the stars in the night sky as their guide. One of the first things ancient stargazers did to help them navigate the night sky and the surface of the Earth was to create a coordinate system to pinpoint relative positions of the stars in the night sky in relation to one another.

Looking upward into the night sky, imagine the sky above you as a sphere of infinite size, centered on the Earth. This technique works in general because distances to the stars above you is not discernible using your naked eye, so the objects you see above you in the night sky all appear to lie on a great sphere at an infinite distance in relation to you.

Modern astronomers use two coordinate systems to determine the relative positions of objects in the night sky; the altitude-azimuth coordinate system and the equatorial coordinate system. We will talk a little about both coordinate systems currently being used by modern astronomers to help them plot the positions of the objects they view in the night sky and using celestial objects you view on your “Journey to the Beginning of Space and Time” to navigate your way through the universe.

The altitude-azimuth system works fine

In the altitude-azimuth coordinate system, altitude indicates the number of degrees from the horizon to the object in the night sky you’re viewing and ranges from 0 degrees at the horizon to 90 degrees at the zenith above you. Modern astronomers measure azimuth along the horizon from north to east, to the point where a line passing through the object in the night sky intersects the horizon at a right angle, and azimuth varies between 0 degrees and 360 degrees. Astronomers also subdivide each degree of azimuth into 60 arcminutes and each arcminute into 60 arcseconds, which helps to further subdivide the immense distances between each degree of measurement in the night sky.

 
 
Navigating the night sky becomes a lot easier using a coordinate system

The altitude-azimuth coordinate system doesn’t take into account the rotation of the Earth, though, and astronomers have solved this problem by fixing coordinates to the celestial sphere you imagine above you in the night sky. Celestial cartographers have created “celestial globes”, similar to the globes of the Earth that cartographers have devised for centuries to show the Earth and all of its features. On these celestial globes, you’ll find terms like the celestial equator and North and South celestial poles.

 
The equatorial coordinate system works even better for navigating the night sky

In the equatorial coordinate system, astronomers use two aspects called declination and right ascension to fix a star’s position on the celestial sphere you picture above you. Declination is analogous to Earth’s latitude and represents the angle between the object you’re viewing in the night sky above you and the celestial equator. Declination varies between 0-90 degrees, North and South of the celestial equator, and is measured in degrees, arcminutes, and arcseconds while a minus sign is used to designate objects south of the celestial equator.

The equatorial system is more widely used today

The lines of circles that run through the celestial poles perpendicular to the celestial equator represent the hour circle of objects in the night sky above your head and are analogous to the meridian of longitude on the Earth. In order to fix an object’s position in the celestial sphere above you, we’ll also need to set the zero point of the longitude coordinate of the object, which astronomers call the object’s right ascension. In order to accomplish this, we need an intersection point between the Earth’s equator and its orbital plane, the ecliptic. Astronomers call this intersection point the vernal equinox and the sun appear to travel through the intersection point annually around March 21, as it moves South to North crossing the celestial equator.

The angle that lies between the vernal equinox and the point where the hour circle of the celestial object in question intersects the celestial equator is the right ascension of the object you see in the night sky. Right ascension is measured in hours (h), minutes (m), and seconds (s), from west to east, and the vernal equinox is zero-hour. There are about 24 hours in each day on the Earth, so each hour of right ascension in the night sky corresponds to 15 degrees of longitude.

The movement of the Earth and the objects in the night sky above you mean the appearance of the night sky is dynamic in nature, so celestial objects will appear to circle the celestial poles as you watch the night sky. A star with a greater distance from a celestial pole than your latitude will only be visible to you during a portion of its orbit. In this case, the star will rise in the east and set in the west. Stars that are always above your horizon are circumpolar for your latitude and you’ll see these stars for their entire orbit.

The Earth’s rotation and the movement of the stars also mean the constellations in the night sky above you travel slowly westward during the year. Pinpoint a star you know well in the night sky at exactly 9 P.M. tonight. This same star will be in the exact same position in the night sky tomorrow night, only 4 minutes earlier, at 8:56 P.M. Check the time this same star is in the same position on the next night and you’ll see this occurs at 8:52 P.M.

Do a little math and you’ll verify that in one month this set up would leave the stars in the night sky 2 hours out of phase with our first positional reading in the night sky for this same star. In 3 months, generally one season, the stars in the night sky above you will have traveled a quarter of the way across the night sky. After four seasons, this would bring the star in question back to the same position in the night sky as twelve months before.

One way to estimate distances in the night sky above you and give yourself a tool to help you navigate the universe on your “Journey to the Beginning of Space and Time” is to use star pairs in the night sky as your guide. Star travelers can learn by using star pairs in the Big Dipper, for example.

On a star atlas, you’ll see objects on the map described as 12 degrees from such-and-such a star. If you study the separations between the stars of well-known stars, like the ones in the Big Dipper, you can train your eyes to visually estimate distances between stars. Take a look at a star chart of the Big Dipper and you’ll see that Alpha Ursae Majoris is about 5 degrees separated from Beta Ursae Majoris. Delta Ursae Majoris, on the other hand, is 10 degrees from Beta Ursae Majoris, while Beta Ursae Majoris is about 25 degrees from Eta, and this trend continues. Star gazers can learn to visually estimate graduations less than 1 degree in the night sky as well. Use the Full Moon, which measures 1/2 degree across. This distance is close to the distance between two stars in Scorpio’s stringer and if you use it as your measuring stick, you’ll see other pairs with about the same separation in the night sky above you. Search the night sky as you “Journey to the Beginning of Space and Time” for road markers and celestial objects you can use to navigate your way to infinity. This will help you find your way back from your trip and navigate the night sky to the objects you want to view.

Check out this astronomy site at http://astronomytonight.yolasite.com/, and then let me know what you think?

Learn how NASA astronomers are planning on detecting extraterrestrial moons orbiting distant suns https://spaceshipearth1.wordpress.com/2013/12/31/searching-for-extraterrestrial-moons/.

Read about the latest news on life beyond Earth https://spaceshipearth1.wordpress.com/2013/12/25/the-search-for-life-beyond-earth-takes-a-turn-at-jupiter/.

Take a look at the latest natural color images taken by the Cassini spacecraft https://spaceshipearth1.wordpress.com/2013/12/22/cassini-spacecraft-show-views-of-the-solar-system-in-natural-color/.

The Earth’s Movements: Spaceshipearth1’s Orbit

 

The Earth is moving at several different velocities at this very moment

 

The combination of the Earth’s movements helps to create the seasons and environment of Spaceshipearth1

The Earth’s orbit around Sol and other things

A little seasoning anyone!

All motion is relative according to Einstein’s theories of space and time

Astronomy answers and questions – The Earth beneath you and the night sky above you are both moving relative to each other and you, and the universe around you. The Earth not only spins counterclockwise on its axis but also orbits Sol about once every 365 spins on its axis, give or take a few minutes, in a counterclockwise direction. Speeding through space and time at an impressive 100,000 km/hr (60,000 miles/hr), around 100 times faster than a speeding bullet, faster than the launch speed for any known spacecraft and certainly faster than Superman, the Earth’s orbit isn’t a perfect circle. In fact, the distance of the Earth to Sol during its transit differs significantly at different times, due to this non-circular orbit, but on average the distance between Earth and Sol is about 150 million kilometers (93 million miles). This distance astronomers call an astronomical unit or AU, and this unit is used by astronomers as a measuring stick of sorts, only on a bigger scale than the mile or kilometer.

Up and down has no meaning

The axis of the Earth during its orbit is also tilted about 23 1/2 degrees from the line perpendicular to the flat plane traced out by the Earth’s orbit around Sol. This flat plane astronomers call the ecliptic plane and in reality, this axis tilt has no meaning in Einstein’s spacetime and is only useful in relation to the ecliptic plane. In Einstein’s universe, the notion of tilt by itself has no meaning in spacetime, where up and down are related to away from the center of the Earth (or any body with mass) and toward the center of mass, respectively.

The Earth’s axis also continues to point in the same general direction throughout Earth’s orbit of Sol. This direction is toward Polaris, often called the North Star by travelers and navigators, and lies within 1 degree of the north celestial pole, which makes it useful for navigating on the surface of Earth. This direction closely marks the direction of due north in the night sky and the altitude of Polaris is nearly equal to the latitude of an observer on the surface of Earth. Navigators and star gazers have used these facts for thousands of years to determine direction and location on the Earth’s surface and travel from one destination to another.

The changing position of Earth during the 365 days it takes the Earth to complete one orbit also results in the night sky above your head changing nightly. Sol appears to move against a background of distant stars in the 88 constellations in the Milky Way above you. The 12 constellations along the ecliptic plane star gazers refer to as the constellations of the Zodiac, but a thirteenth constellation, Ophiuchus lies partially on the ecliptic plane, as well.

Earth’s movements help create seasons

The combination of the rotation of the Earth on its tilted axis and orbit around Sol also helps create the seasons we experience on Spaceshipearth1. In future articles, we’ll talk about the seasons of Earth, the meaning this has for life on Earth, and how this relates to the study of the movements of the exo-planets humans have, so far, viewed during the human “Journey to the Beginning of Space and Time”.

Check out my newest astronomy site at http://astronomytonight.yolasite.com/.

Learn how NASA astronomers are planning on detecting extraterrestrial moons orbiting distant suns https://spaceshipearth1.wordpress.com/2013/12/31/searching-for-extraterrestrial-moons/.

Read about the latest news on life beyond Earth https://spaceshipearth1.wordpress.com/2013/12/25/the-search-for-life-beyond-earth-takes-a-turn-at-jupiter/.

Take a look at the latest natural color images taken by the Cassini spacecraft https://spaceshipearth1.wordpress.com/2013/12/22/cassini-spacecraft-show-views-of-the-solar-system-in-natural-color/.

The Spinning Earth

Astronomers have to compensate for the motion of the Earth in their calculations
The earth rotates on its axis in about 24 hours, give or take a few minutes

The Earth rotates on its axis each day

The Earth goes through a number of different positions which astronomers have measured

We’re always in constant motion

Astronomy questions and answers – The Earth is constantly in motion relative to everything around it and rotates on its axis once every day and orbits Sol once per year. The Earth’s axis is defined as an imaginary line connecting the North and South poles and passing through the center of the planet. The Earth rotates west to east, viewers above the North Pole will see the Earth move counterclockwise from their view, and this is why to star gazers the Sun and stars appear to rise in the east and set in the west every day.

Looking upward at the night sky you don’t actually feel the relative motion of the Earth beneath you, despite this you’re rotating at about 1000 km/hr, depending on where you’re situated on the Earth. Standing in the exact center of the North Pole, your relative speed of rotation is much less than if you were standing on the equator, and the closer you’re to the equator, the faster the Earth beneath you is moving. Standing on the equator the Earth beneath you is rotating at about 1,670 km/hr, move half-way to the North or South Pole, and the speed of rotation of the Earth decreases significantly to about 1,275 km/hr, and once you are standing on the exact North or the South Pole the Earth isn’t rotating. The rotation of the Earth on its axis has consequences for the planet and all life existing on the spaceshipearth1. The daily rotation of the Earth on its axis creates the night and day cycle we all rely on, and this motion combined with the spaceship earth’s orbit around Sol produces the seasonal cycles we all experience during life on Earth. We’ll talk about the Earth’s daily cycle and what this means for life on Earth in future articles.

The spinning Earth makes many things possible

 Check out my newest astronomy site at http://astronomytonight.yolasite.com/.
 

The Moving Universe

The Earth is moving relative to everything else in the universe

Everything on your “Journey to the Beginning of Space and Time” is moving relative to everything else in the universe

The Earth rotates on its axis

The solar system is moving through the Milky Way

Astronomy questions and answers – Staring upward at the night sky above you get the notion you’re stationary in the universe, but nothing could be further from the truth. The Earth beneath you is spinning on its axis at 1000 km/hr, orbiting Sol at 100,000 km/hr, the Milky Way Galaxy at 800,000 km/hr while the solar system is moving relative to the local stars at 70,000 km/hr. In fact, the universe around us could be moving through a relative space and time of some unknown kind unimaginable to the human consciousness, and we would have no way of detecting this relative motion. We are all travelers in a sense on spaceshipearth1, which is the only habitable planet we know of for humankind that exists in the universe.

The Milky Way is moving through the universe

Everything appears to be moving relative to everything else we view as we look outward into space and time, which makes traveling through space and time a hazardous activity at the best of times. The universe you’ll experience on your “Journey to the Beginning of Space and Time” isn’t the universe you experience on Earth. The relative motions of everything in the universe mean we’ll need to explain a few things to you about the way things work in the universe. In future articles, we’ll talk about the Earth’s rotation and orbit around Sol, and how this affects the planet, we’ll explain the Earth’s motion in the Milky Way Galaxy, and the motion of our solar system in relation to the nearby stars in the night sky. This will give you a base upon which to stand as we take you further out into the cosmos to explain the relative universe you’ll experience during your journey. Toward this goal, we’ll explain the meaning of Einstein’s General and Special Relativity for your trip and the way you’ll experience things during your journey.

Check out my newest astronomy site at http://astronomytonight.yolasite.com/.

Learn why astronomy binoculars are a popular choice with amateur astronomers

Read about the Anasazi Indians

Read about astronomers viewing a supernova they think might have given birth to a black hole

A True Pioneer of the Human Journey to the Beginning of Space and Time

Crater Goddard is a good object to begin a young astronomers study of the Moon
Crater Goddard arcs past the Moons’ eastern limb during a few nights in October, beginning on the 10th

The Moon dances, spins and twirls and crater Goddard arcs past your view

On the 10th of October, you’ll see lots of real estate between the Moon’s eastern limb and Mare Crisium

The Moon was one of the first celestial objects viewed by man

Star gazers can pay respects to a true pioneer of human space travel Robert Goddard beginning on the night of October 10th, by taking a journey to the Moon to view the crater named after this gentleman of astronomy. Your view of the Moon’s crescent will show plenty of open landscape between the Moon’s eastern limb and Mare Crisium on this night.

Astronomy News – A large oval plain encompassing an area 270 miles wide by 350 miles long, with the long side running east to west, Mare Crisium will appear different on this night because of the foreshortening of the lunar globe. Mare Crisium also stands alone on the surface of the Moon and isn’t interconnected with the other maria you’ll view on the Moon’s surface during your “Journey to the Beginning of Space and Time”. The last place on the Moon’s surface to be visited by mankind, Mare Crisium, or the Sea of Crises, was host to the unmanned soviet spacecraft Luna 24 in 1976. Look for dark patches along the Moon’s limb on October 10th, which is actually hardened lava of Mare Marginis, the Sea on the Margin, and finds the short white arc just beyond the eastern shore of the sea. This short white arc is the illuminated rim of crater Goddard. Watch as Goddard arcs past the Moon’s eastern limb over the next few nights and you’ll get a good lesson in how the Earth’s satellite moves as the Moon’s eastern limb rotates away from Earth.

On October 15th, Goddard will appear in profile and you should see the rim of this crater poking outward, like two towering peaks framing a darker interior. On October 18th, Goddard will have disappeared over the limb and only about half of Mare Marginis will be viewable. On October 22nd, the Moon will be in full phase at 9:37 P.M. EDT and only an outline of the shoreline of Mare Marginis will be visible. By this time, Mare Crisium will appear much closer to the limb and is prominent in your view of the Moon.

Take a young astronomer on a journey to the Moon tonight

Why does Mare Crisium appear closer and what causes this visual sleight-of-hand? The Moon actually spins at a pretty constant rate, generally completing one rotation on its axis each month. In the same time frame, however, the Moon orbits the Earth on an elliptical path, and this means the Moon’s speed of rotation will vary. This allows viewers to see a few degrees beyond the normal limb of the Moon during specific time frames of the lunar cycle, which is an effect an astronomer refers to as the libration of the Moon.

Learn why astronomy binoculars are a popular choice with amateur astronomers

Read about the Anasazi Indians

Read about astronomers viewing a supernova they think might have given birth to a black hole