If tonight is nice and clear, I'm gonna skywatch again .

I've teased you enough. Back to the question of what it would take to completely sterilize the Earth of all living organisms, including that hearty little creature, the tardigrade. Obviously, it would take an event that would release enough energy to boil away all of the planet's oceans, since the tardigrade is a water inhabitant.

 

According to researchers, it would take 6 X 10^26 Joules of energy to bring all of Earth's water above 212 F . To give you an idea of just how much energy this is, it is a million times more energy than the total annual human consumption and it is a quadrillion times the energy required for the space shuttle to lift off.

 

In terms of an asteroid impact, it would take an asteroid around the size of the largest ones in the solar system. No asteroid that size is headed our way or likely to head our way anytime soon. If not a giant asteroid, then what ??? Other possible cataclysms that scientists considered are supernova explosions(exploding stars) and gamma ray bursts.

 

For a supernova to give off the heat required to boil off all of Earth's oceans , it would take an explosion just 0.13 LY away , more than 30 times closer than the nearest supernova candidate. Additionally, there is close to zero probability of a gamma ray burst occurring at a distance necessary to strip away all water on the planet. It's not gonna be that easy to sterilize our planet of all living organisms.

 

Keep in mind those hearty little tardigrades can withstand a range of temperatures temperatures from 496 F below zero to 304 F above zero. They can withstand pressures up to six times those found at the bottom of the ocean and radiation levels thousands of times what would be lethal for you and I. What they couldn't survive is prolonged exposure to extreme heat or cosmic radiation --- WITHOUT WATER!!!

 

The findings I have relayed to you above have implications for more than folks like you and I. They also have important implications in our search for life elsewhere in the universe. These results show that we can really broaden our range of places where we can search for life. Tardigrades and other microorganisms that can thrive in extreme conditions on Earth may be able to survive a wide range of catastrophes. Thus, there may be living organisms on planets that we previously thought would be too hostile for life to exist.

Did anyone see brilliant Jupiter just below the moon this evening??? A nice late July celestial treat!!!!

Here are some things to watch for beginning tonight through August 6.

 

Friday, July 28

 

The waxing crescent Moon appears about one-third illuminated this evening, when it lies just 3° above brilliant Jupiter. The two stand about 25° high in the southwest an hour after sundown and look spectacular from then until they set after 11 p.m. local daylight time. Although the naked eye and binoculars show this conjunction best, a telescope delivers great views of magnitude –1.9 Jupiter all week. The giant planet’s disk spans 35" and shows a wealth of detail in its massive atmosphere.

 

Saturday, July 29

Mercury pops out of the twilight glow this evening as the sky begins to darken. The innermost planet lies 27° east of the Sun tonight, its greatest elongation for this evening apparition (the configuration officially occurs at 1 a.m. EDT on the 30th). Look for it 30 minutes after sunset, when it lies some 8° above the western horizon. The planet should be fairly easy to spot because it shines brightly, at magnitude 0.3. (Use binoculars if you can’t see it with your naked eye.) Through a telescope, Mercury appears 8" across and slightly less than half-lit.

 

The Southern Delta Aquarid meteor shower reaches its peak overnight, but meteor rates remain essentially the same from July 27 to August 1. And with the nearly First Quarter Moon setting around midnight local daylight time, early morning viewing conditions should be ideal. The meteors appear to radiate from the constellation Aquarius, which rises in late evening and appears highest in the hours before dawn. At its best, the shower produces 20 to 25 meteors per hour under a dark sky, though the highest rates occur at tropical locations and in the Southern Hemisphere.

 

Sunday, July 30

First Quarter Moon arrives at 11:23 a.m. EDT. Our satellite won’t rise until around 1:30 p.m. local daylight time, however, so observers in the Americas won’t see it precisely half-lit. As darkness falls this evening, the Moon appears about 55 percent illuminated and resides among the background stars of Libra the Scales.

 

By the time morning twilight starts to paint the sky, brilliant Venus already dominates the scene. The planet rises around 3 a.m. local daylight time and stands 10° high at the start of twilight an hour later. It’s hard to mistake Venus for anything else — at magnitude –4.0, it shines far brighter than any other object in the morning sky. Although the view with the naked eye or through binoculars is dazzling, you’ll need a telescope to see the planet’s 15"-diameter disk, which appears nearly three-quarters illuminated. Venus treks rapidly eastward relative to the background stars all week. This motion carries it from Taurus the Bull into Orion the Hunter today, but it remains in this non-zodiacal constellation for just two days. On August 1, the planet will cross into Gemini the Twins.

 

Monday, July 31

Pluto reached the peak of its 2017 appearance earlier this month, and it remains a tempting target for those with an 8-inch or larger telescope. The 14th-magnitude world is visible all night among the background stars of northeastern Sagittarius, some 1.3° east-southeast of 3rd-magnitude Pi (p) Sagittarii. See “In pursuit of Pluto” in the July Astronomy for complete details on finding this world.

 

Tuesday, August 1

 

Jupiter resides in front of the 11th-magnitude spiral galaxy NGC 4941 this evening. Although visual observers have no hope of seeing the two in the same telescopic field of view, astroimagers might be able to capture both. Plan on taking multiple exposures to show the bright planet, its fainter moons, and the dim spiral. Perhaps your best bet is to capture a series of images over several nights to record the planet’s passage by the galaxy.

 

Wednesday, August 2

The waxing gibbous Moon stands at its highest point above the southern horizon as darkness falls this evening. If you look a few degrees to its lower left, you can’t miss Saturn. The glorious ringed planet shines at magnitude 0.3 and shows up nicely against the backdrop of southern Ophiuchus on any clear night. When viewed through a telescope, Saturn’s globe measures 18" across while its dramatic ring system spans 40" and tilts 27° to our line of sight.

 

The Moon reaches apogee, the farthest point in its orbit around Earth, at 1:55 p.m. EDT. It then lies 251,671 miles (405,025 kilometers) from Earth’s center.

 

Thursday, August 3

Uranus’ eastward motion against the background stars comes to a halt at 6 a.m. EDT. This so-called stationary point marks the beginning of the best period to observe the outer planet. Uranus rises before midnight local daylight time and appears more than halfway to the zenith in the southeastern sky as morning twilight commences. The magnitude 5.8 planet lies in Pisces, 1.2° north of magnitude 4.3 Omicron (o) Piscium. A telescope reveals Uranus’ blue-green disk, which spans 3.6".

 

Friday, August 4

 

Look overhead around 11 p.m. local daylight time any day this week and your eyes will fall on the brilliant star Vega in the constellation Lyra the Harp. At magnitude 0.0, Vega is the brightest member of the prominent Summer Triangle asterism. The Triangle’s second-brightest star, magnitude 0.8 Altair in Aquila the Eagle, lies some 35° southeast of Vega. The asterism’s dimmest member, magnitude 1.3 Deneb in Cygnus the Swan, stands about 25° east-northeast of Vega. Although the waxing gibbous Moon diminishes the luster of stars this week, the Summer Triangle remains conspicuous.

 

Saturday, August 5

 

Distant Neptune reaches opposition and peak visibility in just a month, but the view now is essentially the same. The ice giant planet rises around 9:30 p.m. local daylight time and climbs nearly halfway to the zenith in the southern sky by 3 a.m. The magnitude 7.8 planet lies in Aquarius, 2° east of 4th-magnitude Lambda (l) Aquarii. You’ll need binoculars to spy Neptune and a telescope to see its blue-gray disk, which spans 2.4".

 

Sunday, August 6

 

Asteroid 89 Julia should be relatively easy to find through small telescopes south of the Great Square of Pegasus. Your signpost for finding this magnitude 9.6 space rock is a squashed box of four 5th-magnitude stars: 55, 57, 58, and 59 Pegasi. The box lies 6° south of magnitude 2.5 Markab (Alpha [a] Peg), the star that marks the Great Square’s southwestern corner. Tonight, Julia stands 1.5° south of 59 Peg. If you sketch the field and then return to the same area a night or two later, you should be able to detect the asteroid’s movement relative to the stellar background.

Planets in the sky this week:

 

Mercury fades from magnitude +0.2 to +0.6 this week and is also sinking lower in the afterglow of sunset. Look for it just above the due-west horizon 30 minutes after sundown.

 

Venus (magnitude –4.0) shines brightly in the east before and during dawn. Watch the changing shape of the triangle it forms from morning to morning with fainter orange Aldebaran to its upper right and orange Betelgeuse rising to its lower right.

 

Mars is hidden behind the glare of the Sun.

 

Jupiter (magnitude –1.9, in Virgo) shines brightly in the west-southwest in early evening. Fainter Spica (magnitude +1.0) glitters 7° or 8° left of it. In a telescope, poor Jupiter has shrunk to 35 or 34 arcseconds wide as it swings toward the far side of the Sun from Earth's viewpoint.

 

Saturn (magnitude +0.2, in the legs of Ophiuchus) glows steadily in the south at nightfall. Fiery Antares, less bright, twinkles 13° to Saturn's lower right. Delta Scorpii, the third-brightest object in the area, catches the eye less far to the right or upper right of Antares.

 

Uranus (magnitude 5.8, in Pisces) and Neptune (magnitude 7.9, in Aquarius) are high in the southeastern sky in the hours before the first light of dawn.

I love Betelguese!!! Why don't you see if you can spot the red supergiant this week.

If you are up before dawn this week, look to the eastern sky and you will see brilliant Venus. Two stars will form a triangle with Venus this week with a faint orange star, Aldabaron, to its upper right and the brighter orange Betelguese to Venus' lower right. If you are up before dawn each morning you will notice the shape of the triangle changing from day to day.

 

Betelguese is the ninth brightest star in the night sky and the second brightest in the constellation Orion. Distinctly red in color, Betelguese is a semi-regular variable star and is one of three stars that make up the Winter Triangle asterism and marks the center of the Winter Hexagon. Interestingly enough, if the human eye could see all wavelengths of radiation, Betelguese would be the brightest star in the night sky!!! While Betelguese can be seen in the summer months, the dark skies of the winter months make for optimal viewing of the big red giant.

Just released this past Wednesday !!!!

 

The Atacama Large Millimeter submillimeter Array, better known by guys like me as ALMA, captured the highest resolution image of Betelguese ever seen. Look below and you will see the surface of Betelguese. This picture reveals the hot gas of the lower chromosphere at sub-millimeter wavelengths. Localized increased temperatures help explain why it is asymmetric.

 

Past observations of Betelguese have granted astronomers the opportunity to view a vast plume of gas almost as large as our solar system and a humongous bubble that boils away on the surface of Betelguese. Such observations help us to explain how the supergiant star is shedding gas and dust at such tremendous rates.

 

Remember, this star may be only 8 + million years old but she is getting ready to blow!!!! (Sometime between tonight and a million yrs. from tonight) And when she does, Betelguese will be visible from Earth even in broad daylight !!! Stay tuned...

 

^^^

 

Not a bad pic for a star that is 3,855,000,000,000,000 miles away!!!!!

I plan on posting here from somewhere within the band of totality the weekend before the GAE on the 21st. My location on that weekend will depend heavily upon the weather forecast. I will make every effort to get to where clear skies are in the forecast. I want to encourage others who are traveling to see the eclipse to post in this thread about the "atmosphere" of your surroundings? I suspect it will be crazy most anywhere within the totality band.

What makes a TOTAL solar eclipse like the one we will experience in August such a unique cosmic event in our solar system??? Stay tuned....

Just released this past Wednesday !!!!

 

The Atacama Large Millimeter submillimeter Array, better known by guys like me as ALMA, captured the highest resolution image of Betelguese ever seen. Look below and you will see the surface of Betelguese. This picture reveals the hot gas of the lower chromosphere at sub-millimeter wavelengths. Localized increased temperatures help explain why it is asymmetric.

 

Past observations of Betelguese have granted astronomers the opportunity to view a vast plume of gas almost as large as our solar system and a humongous bubble that boils away on the surface of Betelguese. Such observations help us to explain how the supergiant star is shedding gas and dust at such tremendous rates.

 

Remember, this star may be only 8 + million years old but she is getting ready to blow!!!! (Sometime between tonight and a million yrs. from tonight) And when she does, Betelguese will be visible from Earth even in broad daylight !!! Stay tuned...

 

[ATTACH]63048[/ATTACH]

 

Fascinating stuff!

Fascinating stuff!

 

Thank you. I really appreciate you following and enjoying the thread.

I googled the largest stars in the Milky Way galaxy and discovered that the largest star, if placed in our solar system, would have a surface that would be beyond the orbit of Jupiter, or around 540 million miles from its center. That's mind boggling when put in that perspective!

As I mentioned earlier in the thread, the GAE of 2017 is a pretty special eclipse. The band of totality is about 70 miles wide and stretches from central Oregon all the way to South Carolina. It has been 99 years since such a large swatch of the U.S. has been within the band of totality.

 

Have you ever pondered the question: " How unique is this phenomenon of a total eclipse in our solar system? " How often do you think it happens elsewhere within the solar system?

 

Well, let me tell you, it is indeed unique to the Earth-Moon-Sun shadow dance. Think about what an incredible coincidence makes the phenomenon of a total eclipse possible. When viewed from Earth, the apparent diameters of the Moon and Sun must be identical. That is, when we view the Sun and Moon , their diameters appear to be the same. Now, is this always the case? No. Since both the Earth's orbit around the Sun and the Moon's orbit about Earth are elliptical, the relative sizes of the Sun and Moon can vary slightly. But every year to two years(the average is about 18 months), apparent diameters of the two bodies are identical , resulting in a total eclipse that can be viewed somewhere on the Earth's surface. That's about two total eclipses every three years, on average.

 

I can't stress to you enough just what an extraordinary phenomenon this is!!! The Moon and Sun have to be the exact size , as viewed from Earth, in order for us to view the phenomenal corona of the Sun during a total eclipse. If the Moon was a lot smaller, the eclipse would still be nice but not nearly as impressive. If the Moon was quite a bit larger, then it would completely blot out the Sun and rob us of any opportunity to see the corona.

 

The allure of an apparent exact match of the size of Sun and Moon is that it reveals the magnificent corona, often described as one of the most awe-inspiring sights in nature. In the two or two and one-half minutes of totality on Aug. 21, make sure that you don't miss viewing the Sun's corona in all it's glory. The corona will be the star of the show!!!

 

Btw, when the Sun is at its apparent largest and the Moon at its smallest, the Sun is not totally eclipsed(even though the Moon passes directly between Earth and Sun), we have what is called an annular eclipse.

 

Now, if you were on one of the other planets in the solar system , would you ever view an eclipse like the one we will be privileged to view in less than three weeks? The answer is a definitive "NO !"

 

The phenomenon of a total eclipse of the Sun by the Moon is most certainly unique in our solar system.

For one, Mercury and Venus have no moons. Can't have an eclipse without an eclipser. Mars' two moons are way too tiny to do the job. As for the gas giants, some of their moons are pretty large but are dwarfed by their host planets. Besides, none of these moons have apparent sizes(as viewed from the planet) that are exactly the same as the apparent size of the Sun. So, the bottomline is, while it's possible that a moon such as Titan could occasionally eclipse the Sun, it would in no way be like what we experience here on Earth. What we get to experience is due to the remarkable, extraordinary coincidence that the Moon and Sun have the apparent exact same size when viewed from Earth!!!!

 

As for other solar systems in the Universe--- there are billions and billions of them(in my best Carl Sagan voice). So I suppose it's possible that there is another planet-moon-star system that allows for the kind of eclipse that we are privileged to view this month. But keep in mind, the mathematics has to be exact--- identical diameters of star and moon as viewed from the planet in order to have this kind of total eclipse. Could we be the only inhabitants in the universe that are lucky enough to benefit from this amazing coincidence of nature???

 

Don't miss the show on the 21st!!! It's unique to the solar system and quite possibly to the entire universe.

I googled the largest stars in the Milky Way galaxy and discovered that the largest star, if placed in our solar system, would have a surface that would be beyond the orbit of Jupiter, or around 540 million miles from its center. That's mind boggling when put in that perspective!

 

You are correct. I was thinking about that just a couple of weeks ago. Excellent post!!!