Apr 01

What’s Up in the Sky

What’s Up in the Sky – April, 2018

The April Sky Has Much to Offer

Sky watchers in April should enjoy a month that begins with the appearance of one of the brightest objects in the sky, the planet Venus. Considering the clear weather we’ve been having recently (rather unusual for March) many readers have probably already spotted Earth’s sister planet low in the west after sunset. April will see Venus become higher in the sky and set a full hour later, making it even easier to see. On the seventeenth the goddess of love is joined by a thin crescent Moon, a spectacular sight indeed.

As the month begins, Jupiter shines brilliantly in the southwest before sunrise and is also visible at night, rising three hours after sunset. The time shortens to half an hour after sunset by April 30 and around mid-month Jupiter starts rising before Venus sets. Look each evening to find out the first date you can see both bright planets at the same time.

Mars and Saturn put on quite a show early in April, shining just above the Teapot in Sagittarius. Starting on April 1, if you look about an hour before sunrise on consecutive days, you will easily see how their positions change relative to one another. They will be joined by an almost-last-quarter Moon on the seventh.

Although the spectacular constellations of winter such as Orion, Gemini, and Taurus are still visible in the west, they are slowly fading and dropping out of view. They are replaced by Leo, the lion, high in the southern sky as April progresses. If you turn around, face north and look almost straight up, you will see Ursa Major, aka the Big Dipper, almost directly opposite from Leo with respect to the zenith. Many people don’t think of the Bear and the Lion as being so closely related to each other in the sky, but it is an interesting combination at this time of year.

Like Orion the Hunter, Leo is recognizable because it clearly resembles its namesake, a lion. It’s backward question mark head faces west, followed by a triangle of stars forming its hindquarters and tail. The bottom of the question mark is the bright star Regulus. The sixteenth century astronomer Copernicus gave the star its name which means “little king” and reflects the ancient belief that this was one of the royal stars which ruled the heavens. Many scholars believe that the sphinx of Egypt, a figure with a human face and the body of a lion, associated the royal power of the Egyptian kings with the impressive celestial symbolism of Leo the Lion.

Luckily, in April you don’t have to be royalty to appreciate what’s up in the sky.

This month in history:

April 1: Comet Hale-Bopp nearest Sun – 1997
April 9: NASA selects original seven Mercury astronauts – 1959
April 12: Yuri Gagarin becomes first human in space – 1961
April 12: Columbia becomes first space shuttle to be launched – 1981
April 17: Apollo 13 returns to Earth – 1970
April 20: Shapley-Curtis debate on the distance and nature of spiral nebulae – 1920
April 25: Hubble Space Telescope is deployed – 1990
April 28: Eugene Shoemaker is born – 1928

Mar 02

What’s Up In The Sky?

Do We Spend Too Much on NASA?

Mark Rober is probably not a name familiar to many people. That’s too bad because he has a very interesting YouTube channel which you can easily find by typing his name into the search window. His latest post is the inspiration for this month’s column.

Its title is “Is NASA a waste of money?” I would hope that most readers would answer “no” to that question, but can you come up with five good reasons why we don’t? I hope the following provides you with some solid arguments to use the next time you get into a discussion with a skeptic.

Mark is a former NASA engineer who worked on the Curiosity rover and a project called SMAP. One might argue that he is therefore biased in his opinion, but I would counter by saying that makes him an expert on the various projects on which NASA spends money.

First consider this: what percent of the US budget do you think goes to NASA? Most Americans think it’s about 20 percent, which helps explain why one in four think its budget should be reduced. The truth is it’s about one half of one percent, or about nine dollars a year for most of us.

So what are we getting for our one-half penny of every dollar? First, about half of the missions currently operating are studying the earth, helping us understand such things as how to improve agriculture and preserve our natural resources. The SMAP satellite monitors the moisture content of the soil and its data is shared for free with anyone in the world, helping them increase their food production. Second are the instruments on Earth used to find and track asteroids, like the one that hit our planet 65 million years ago. The dinosaurs probably wished they had seen that coming. We not only track such objects, but also are working on ways to prevent a similar catastrophe.

Third is what Mark calls “offshoot technology”. Digital cameras, GPS, live TV beamed from satellites (think Olympics) and accurately tracking hurricanes are just a few of the two thousand technology spinoffs from NASA. And expecting NASA to justify its funding by predicting what will be discovered is like Queen Isabella expecting Columbus to predict Netflix.

Fourth, is the economy. The majority of NASA’s budget goes toward the salaries of the scientists and skilled technicians who work there. Much of that money goes back into the overall economy. The same is true for all the companies that exist because of number three, above.

Fifth and foremost, is “exploration and imagination”. Humans have always yearned to find answers to fundamental mysteries of our world. The knowledge gained through research and exploration not only makes us better equipped to deal with many problems but also gives us hope for a better future.

We should be grateful to NASA for helping us understand what’s up in the sky.

Jan 30

What’s Up in the Sky

What’s Up in the Sky – February, 2018

A Super Blue Moon Eclipse

I’m going to cheat a little this month. Although the focus of this column is usually on astronomical events occurring in February, I will be describing an event that happens tomorrow. It’s always cloudy in February anyway.

I am talking about a total eclipse of the Moon. Lunar eclipses occur when the Moon passes through the Earth’s shadow. Unlike a solar eclipse where the Moon casts its shadow on the surface of the Earth, blocking the Sun from the view of only those in the shadow’s narrow path, a lunar eclipse is visible to anyone on the side of the Earth facing the Moon. Unfortunately, that won’t be us, at least not for long because the Moon will be setting over Lake Michigan just as totally begins at 8:00 a.m. And the chances for a clear horizon in late January around here are slim. But if it is clear and you have a view of the horizon, go for it.

But there’s more. I have written before how this column is sometimes inspired by locker room conversations after noon ball and this is no exception. The question was in regards to a “Super, Blue Moon”, a relatively rare event. The discussion morphed into questions about frequency and observability.

First some background. A “Super Moon” occurs when the Moon is at perigee (the point in its orbit closest to Earth) and is also opposite the Sun (a full Moon). The closeness will make it appear slightly larger although the effect is not noticeable to the naked eye. That is why there were no “Super Moons” twenty years ago – the term was invented by the Weather Channel to increase viewer interest. It has no astronomical significance.

The term “Blue Moon” originally referred to the third Full Moon in a season with four Full Moons (rather than the usual three). This is still known as a “seasonal” Blue Moon. But in a 1946 article in Sky & Telescope magazine a misunderstanding of this definition caused the author to erroneously describe the Blue Moon as the second Full Moon in a month. This definition was repeated on a program called “StarDate” in 1980 and even made it into Trivial Pursuit as an answer in 1986. Today, rather than a mistake, it is considered to be a second definition.

Both the seasonal and modern Blue Moons occur once every two or three years on average. That may seem puzzling considering that this year there is a Blue Moon tomorrow and then another one March 31. But that’s because February has too few days to ever have a second full Moon so a Blue Moon in January is always followed by another in March. The next one will be in October 2020.

Now add in the fact that tomorrow the Super Blue Moon will pass through the Earth’s shadow and we have the “Super Blue Moon Lunar Eclipse”. I don’t know how rare that is, but it is definitely very, very cool, just like most things up in the sky.

My thanks to Dr. David Myers, whose questions inspired this article.

This month in history:

Feb 6: Alan Shepard hits first golf balls on the Moon – 1971
Feb 15: Galileo Galilei born – 1564
Feb 18: Clyde Tombaugh discovers Pluto – 1930
Feb 19: Nicholas Copernicus is born – 1473
Feb 20: John Glenn is first American to orbit Earth – 1962
Feb 24: Detection of first pulsar (by Jocelyn Bell in 1967) is announced – 1968

Nov 28

What’s Up in the Sky

What’s Up in the Sky – December, 2017

2017 – An Historic Year for Astronomy

What must it be like to devote an entire career to the study of a particular field and in a period of about two months have two discoveries made for the first time in history? That’s what has happened to astronomers recently.

The events that have the astronomical community in orbit are the detection of two colliding neutron stars and the discovery of a fast-moving object from outside our solar system passing the Sun.

About 130 million years ago in a galaxy far, far away, two neutron stars – the strange, compacted cores of dead stars – crashed into each other. Known as a “kilonova” the explosion sent ripples through space-time and ejected heavy elements such as gold and platinum into space. That’s one new discovery right there – it was previously thought that these elements were formed in the supernova explosions of massive stars.

Several things make this observation so astounding. One is its rarity – astronomers estimate that such a collision occurs in a galaxy like our own perhaps a few dozen times per millions of years. Another is the fact that not only were the gravitational waves from the resulting explosion detected by LIGO, but also, two seconds later, scientists detected a flood of electromagnetic radiation from across the spectrum. This has allowed astronomers and astrophysicists to verify theories concerning some of the most fundamental questions in physics.

In addition verifying the source of heavy elements, they were able to show that gravity waves travel at the speed of light, determine the source of gamma ray bursts, and measure the expansion of the universe much more accurately. Not bad for a single observation.

The second historical event is notable more for its rarity rather than any revealing data it provides. But it is still pretty cool. I’m referring to the discovery of the first observed object known to have originated from beyond our solar system. That determination was made based on its speed and trajectory. It is currently speeding out of our solar system into interstellar space.

Actually, this is not the first interstellar object to make its way into our solar system. Spacecraft have collected and returned samples of interstellar dust and grains of it can be found in meteorites. But this was the first “macro object” of extra-solar origin to be observed.

Regarding the importance of this discovery, Paul Chodas with the Center for Near-Earth Objects Studies said, “we have been waiting for this day for decades”. It was another confirmation of the long-held theory that objects moving between the stars occasionally pass through our solar system.

All in all, it’s been a good year for what’s up in the sky.

This month in history:
Dec. 7: Galileo spacecraft enters Jupiter’s atmosphere – 1995
Dec. 8: Dragon 1, first private spacecraft to be recovered from orbit, is launched – 2010
Dec. 14: Gene Cernan, Apollo 17 astronaut, is last human to walk on Moon – 1972
Dec. 14: Tycho Brahe born – 1546
Dec. 20: Founding of Mt. Wilson Solar Observatory – 1904
Dec. 24: Apollo 8 astronauts give us inspirational moment from lunar orbit – 1968
Dec. 25: Isaac Newton born – 1642

Nov 01

What’s Up in the Sky

What’s Up in the Sky – November, 2017

Halloween and Astronomy?

Happy Halloween! This being the first time this column has been published on Halloween, I thought it might be fun to see if there was any connection between the holiday and astronomy. Turns out there is. And it stems from the customs and beliefs of early cultures.

Many Halloween traditions can trace their origins to the ancient Celtic festival of the harvest called Samhain (pronounced sah-win). But the date itself is also significant in an astronomical sense because it is a “cross-quarter date”.

We mark the beginnings of the seasons with what we call equinoxes and solstices, so the autumnal equinox marks the first day of autumn in September, and the winter solstice the first day of winter in December. But the dates roughly half-way between these seasonal boundaries, the cross-quarter dates, were also important to early cultures. (We still celebrate two other cross-quarter dates, Ground Hog day on February 2nd, and May Day on May 1st.)

To the early Celts, however, these dates marked the middle of the seasons, not the beginning, and so winter, the “dark season” actually began on the cross-quarter date approximately half-way between the fall equinox and winter solstice, October 31. This makes sense to me since November is much more winter-like than March and we often think of summer ending on Labor Day.

That’s where Samhain comes in. Roughly translated it means “summer’s end” and was the start of the dark season when everything died and the days grew cold. It was also the Celtic new-year’s eve and great bonfires were lit to keep evil spirits away. It was a time of both celebration and fear, as the light, living summer gave way to the dark, dead winter.

It was also a time of year when the well known star cluster, the Pleiades, reached its highest point in the sky around midnight. To the Celts, the Pleiades opened a path to the other world and when they reached their highest point in the sky, the barriers between the worlds broke down, and the souls of the dead could cross over into the world of the living.

The Full Moon is often associated with Halloween, usually depicted with the silhouette of a black cat or flying witch on her broomstick. Unfortunately, the Full Moon does not always fall on October 31, but it is a common image. This year, though, trick-or-treaters will be able to see an “almost-Full” Moon low in the southeast after dinner.

So I hope your day is somewhat enriched by the knowledge that your celebration has its origins up in the sky.

This month in history:
Nov. 3: The dog Laika is first living creature to orbit Earth, aboard Sputnik 2 – 1957
Nov. 9: Carl Sagan born. – 1934
Nov. 16: Interstellar message broadcast from Arecibo radio telescope – 1974
Nov. 20: Edwin Hubble born – 1889
Nov. 27: First photograph of a meteor shower – 1885
Nov. 30: Ten-pound meteorite strikes and bruises Alabama woman, Elizabeth Hodges-1954

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