See a conjunction of the Moon and Venus, catch Psyche and Iris at opposition, and watch Jupiter’s Galilean moons dance in the sky this week.
https://www.astronomy.com/observing/the-sky-this-week-from-august-2-to-9-2024/
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This Week's Sky at a Glance, August 2 – 11
MONDAY, AUGUST 5
■ A hairline-thin crescent Moon, less than two days old, hangs just 1° or so above Venus, just above the west horizon in bright twilight. Use optical aid starting 15 or 20 minutes after sunset. Good luck.
■ Standing atop Scorpius in the south after darkness is complete, and butting heads with Hercules much higher, is enormous Ophiuchus the Serpent-Holder. Just east of his east shoulder (Beta Ophiuchi or Cebelrai) is a dim V-shaped asterism like a smaller, fainter Hyades. This is part of the defunct constellation Taurus Poniatovii, "Poniatowski's Bull." The V is 2½° tall and stands almost vertically now.1
The top two stars of the V are the faintest, magnitudes 4.8 and 5.5. The middle star of its left (east) side is the famous K-dwarf binary 70 Ophiuchi, visual magnitudes 4.2 and 6.2, distance just 17 light-years. The two stars of the pair are currently 6.7 arcseconds apart in their 88-year orbit: close but nicely separated at medium-high power in any telescope.
Just 1¼° NNE of Beta Oph is the large, loose open cluster IC 4665, a binocular object. Read more about the whole scene in Matt Wedel's Binocular Highlight column in the August Sky & Telescope, page 43.
https://www.newsweek.com/astronomy-events-space-august-meteor-showers-planets-1933971
The Perseids, one of the most well-known and prolific meteor showers, started July 14 and run until September 1 this year, peaking on August 12. During peak times and under ideal conditions, viewers might witness up to 100 meteors per hour, according to NASA.
The Perseids are known for their brightness and fast speeds. They often leave long, luminous trails and can sometimes produce fireballs—exceptionally bright meteors that can light up the sky.
Meteors will appear to originate near the constellation Perseus, hence the shower's name, but can be seen anywhere in the sky. The meteors can be seen in both the Northern and Southern hemispheres, although they are more prominent in the former. They are best viewed after midnight and before dawn. The moon is due to be 50 percent full on the peak night, which may hinder meteor spotting because of light pollution.
Perseids are caused by the Earth passing through the debris trail left by the comet Swift-Tuttle. As these tiny particles, mostly the size of sand grains, enter the atmosphere at high speeds, they burn up and produce bright streaks of light across the sky.
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These are my favorite meteor showers!
My wife, Deb and I used to take 2 week vacations during the first half of August (because July was ratings month for television and the top anchors-I was chief meteorologist for WEHT in Evansville- were not allowed vacations).
This actually is why we got married on August 10, 1985(also her dad's birthday).
Viewing was especially good when we stayed at places far from the big cities and usually pretty far north, where the air was cooler/less humid and had a high visibility.
This is also why the Winter viewing sky is so much superior to Summer viewing.
You might be more comfortable on a humid night with a temperature in the 70's but the haze and humidity greatly reduce visibility.
A temperature well below freezing is usually the best for star gazers.
In the Summer, a dry continental air mass with the lowest dew points possible is best to observe the less bright objects in the sky.
On the map below, places with dew points at 70+ may list a visibility of 10 miles for surface observations because that's the threshold but the locations with dew points of less than 50, in the Rockies for instance likely have a visibility of double that.
https://thermastor.com/dew-point-and-weather-maps/
Here's another interesting science tidbit.
Humid air WEIGHS LESS than dry air.
This actually makes it less favorable for planes to fly in.
Hugh???
This one is extremely fascinating:
Asked by: Jesse Thune
https://www.physlink.com/education/askexperts/ae652.cfm
Humidity affects the way an airplane flies because of the change in pressure that accompanies changes in humidity. As the humidity goes up, the air pressure for a given volume of air goes down. This means the wings have fewer air molecules to affect as they are pushed through the airmass. Fewer molecules = less lift. The other problem is that jet engines do not like humidity either. Jet engines are built for cold, dry air, and humid air has fewer oxygen molecules to burn per unit volume. Therefore the engine combusts a little bit less and puts out slightly less thrust. There are four factors that decrease the performance of a jet airplane - heavy, hot, high, and humid. Notice that three of those factors all have the net effect of lowering the density of the air. So there you have it. Humidity decreases the performance of most aircraft, not only because of it's effect on the wings, but also the effect on the engines.
Answered by: Frank DiBonaventuro, B.S., Air Force officer, Physics Grad, The Citadel
Humidity has a major affect on the way planes fly. This is due to the weight of the air when it is humid. When air is humid, it is actually lighter then dry air, contrary to common belief. That is because the water (H2O) weighs less then the N2 or O2 that it replaces. So if you take the fundamentals of lift, which is that the curved part of the wing (the top) will cause air to move by it quicker, causing the bottom of the wing to have a higher pressure (with slower moving air), causing lift. If you take humid air (less dense), then the plane can no longer create the amount of lift it could when the are is dry (more dense). This causes pilots to have longer runways to gain speed before enough air is passing the wings per second to create enough lift, it also forces pilots to fly faster then would be required if the air were dry.
Answered by: Steve Smith, None, High School Student
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Here's an example of this for our science nerds:
Assuming dry air being 99% Oxygen (21%) and Nitrogen (78%)
Oxygen Weighs 16 X 2 atoms = 32
32 X 21% = 7
Nitrogen Weighs 14 X 2 atoms = 28
28 X 78% = 22
7 + 22 = Molecular weight of dry air = 29
Now water vapor has 2 atoms of Hydrogen and one Oxygen. 2 + 16 = Molecular weight of water vapor = 18
So if we had two air masses both the same volume, and both the same temperature/pressure. Let's say both masses have 50 molecules of dry air.
50 X 29 = Molecular weight of our dry mass = 1450
But now let's replace 30 of those dry air molecules in the second mass with water vapor.
30 X 18 = Molecular weight of our water vapor in the mass = 540
20 X 29 = Molecular weight of our dry air in the mas = 580
Water vapor 540 + Dry air 580 = Molecular weight of moist air mass = 1120
1450 - 1120 = difference in weight between air mass's = 330
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This also contributes lift/buoyancy to warm air that is already less dense and rises because of the higher temperature AND the higher moisture/humidity/dew point just adds to that.
For optimal auroral viewing, the Moon may not disturb because light from the Moon can be very bright which causes faint aurora to be barely visible, especially when the chances for auroral viewing are low. Below you'll find the Moon Phases for the current and next month so that you'll know exactly when the Moon will be a disturbing factor.
https://www.spaceweatherlive.com/en/moon-phases-calendar/2024/8.html
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You can use this site to find out the moon rise and moon set times as well as the phase of the moon for every day.
Also, a description of the sky.
https://www.timeanddate.com/sun/usa/evansville
https://www.timeanddate.com/moon/usa/evansville
https://www.timeanddate.com/moon/phases/usa/evansville
https://www.timeanddate.com/astronomy/usa/evansville
https://www.timeanddate.com/astronomy/night/usa/evansville
https://www.timeanddate.com/eclipse/in/usa/evansville
Moon in Evansville - Next 7 days
| Aug | Moonrise | Moonset | Moonrise | Time | Distance (mi) | Illumination | ||||
|---|---|---|---|---|---|---|---|---|---|---|
| 2024 | Moonrise/Moonset | Meridian Passing | ||||||||
 Aug 4 | 5:51 am | 8:27 pm | - | 1:14 pm | (71.5°) | 247,134 | 0.2% | |||
| Aug 5 | 6:54 am | 8:53 pm | - | 1:59 pm | (66.6°) | 248,915 | 1.8% | |||
| Aug 6 | 7:55 am | 9:16 pm | - | 2:41 pm | (61.1°) | 250,371 | 5.3% | |||
| Aug 7 | 8:54 am | 9:37 pm | - | 3:20 pm | (55.3°) | 251,383 | 10.5% | |||
| Aug 8 | 9:52 am | 9:57 pm | - | 3:59 pm | (49.4°) | 251,828 | 17.2% | |||
| Aug 9 | 10:50 am | 10:18 pm | - | 4:38 pm | (43.6°) | 251,602 | 25.1% | |||
| Aug 10 | 11:48 am | 10:41 pm | - | 5:19 pm | (38.1°) | 250,626 | 33.9% | |||
| * All times are local time for Evansville. | ||||||||||
Space Weather Prediction Center
National Oceanic and Atmospheric Administration
Most of us UNDERappreciate the incredible, vast Universe surrounding our planet.
https://en.wikipedia.org/wiki/Universe
The universe is all of space and time[a] and their contents.[10] It comprises all of existence, any fundamental interaction, physical process and physical constant, and therefore all forms of energy and matter, and the structures they form, from sub-atomic particles to entire galactic filaments. Space and time, according to the prevailing cosmological theory of the Big Bang, emerged together 13.787±0.020 billion years ago,[11] and the universe has been expanding ever since. Today the universe has expanded into an age and size that is physically only in parts observable as the observable universe, which is approximately 93 billion light-years in diameter at the present day, while the spatial size, if any, of the entire universe is unknown.
 The Hubble Ultra-Deep Field image shows some of the most remote galaxies visible to present technology (diagonal is ~1/10 apparent Moon diameter)[1] | |
| Age (within ΛCDM model) | 13.787 ± 0.020 billion years[2] |
|---|---|
| Diameter | Unknown.[3] Observable universe: 8.8×1026 m (28.5 Gpc or 93 Gly)[4] |
| Mass (ordinary matter) | At least 1053 kg[5] |
| Average density (with energy) | 9.9×10−27 kg/m3[6] |
| Average temperature | 2.72548 K (−270.4 °C, −454.8 °F)[7] |
| Main contents | Ordinary (baryonic)
matter (4.9%) Dark matter (26.8%) Dark energy (68.3%)[8] |
| Shape | Flat with 4‰ error margin[ |