Thursday, July 25, 2024

The Ellensburg, WA sky for the week of July 27, 2024

Saturday: Mercury and Venus are low on the west-northwestern horizon right after sunset. Venus is the brighter of the two. Mercury is a fist to the left of Venus at 9:10 p.m. The star Regulus is to the upper right of Mercury.

Sunday: Have you ever planned a vacation to a place because it was supposedly the up-and-coming locale? Then, when the vacation time finally arrives, you find out the place doesn’t live up to its billing. Seven years ago this month, astronomers strengthened earlier findings that the star Tau Ceti, one of our closest neighbors at 12 light years away, has four planets classified as “super-Earths”. Two of the planets are in the so-called habitable zone where the temperature is just right for having liquid water on their surface. Time for a va-ca-tion! Well, not so fast. Astronomers have only a lower limit to the planet masses so they may be too massive for complex life to form. And the Tau Ceti system has ten times as much mass in dust and rocks as our own solar system. So you’ll want to do some research before you travel there. Tau Ceti is one and a half fists above the southeast horizon at 3:00 a.m. For more information about the discovery, go to https://skyandtelescope.org/astronomy-news/four-exoplanets-may-orbit-nearby-sun-like-star/.

Monday: The Southern Delta Aquarid meteor shower peaks tonight and on into mid-August. Meteor showers are named after the constellation from which the meteors appear to originate. These meteors appear to come from a point in Aquarius near the star Delta Aquarii, also known as Skat. This point is about one and a half fists above the southeastern horizon at 1:00 am tonight. You can follow this point throughout the night, as it will remain a fist above Fomalhaut, the brightest star in that section of the sky, and a first to the lower right of Saturn. The Moon is approaching the new moon phase this week meaning it will not be up for many hours each night. For more information about this year’s shower, go to https://earthsky.org/?p=159138. As your mother might say, dress warm and sit in a comfortable chair for maximum enjoyment. Meteors are tiny rocks that hit the Earth and burn up in the atmosphere.

Tuesday: Clockwise from the top, the moon, Mars, the star Aldebaran, and Jupiter make a crooked diamond shape three and a half fists above due east at 5:00 a.m.

Wednesday: The bright star Altair is four fists above the southeastern horizon at 10:00 p.m.

Thursday: Mizar is a well-known binary star in the constellation Ursa Major. You can find it at the bend in the Big Dipper handle, three fists above due northwest at midnight. Its name is Arabic for waistband. Mizar has an optical double called Alcor, which is less than a pinky width away and can easily be seen with the naked eye. Optical doubles are stars that are close together in the sky but do not orbit a common center of mass as true binary stars. Not wanting to deceive sky gazers who call Alcor and Mizar a binary star, two stars that DO orbit a common center of mass, Mizar actually is a binary. It was the first binary star system discovered using a telescope. Mizar A and Mizar B are about 400 astronomical units apart from each other and about 80 light years from Earth. 400 astronomical units is about 10 times the distance between the Sun and Pluto.

Friday: The Perseid meteor shower peaks in a week and a half. But there will be an increased number of meteors over the next two weeks. If the Moon is out when you want to look, position yourself so you are in the Moon’s shadow. The meteors appear to come from a point just below the W of the constellation Cassiopeia. This point is about two and a half fists held upright and at arm’s length above the northeast horizon at 11:00 p.m. By dawn, this point is about seven fists above the northeast horizon. If you fall asleep or forget to set your alarm, you will be able to observe this shower from about 11 p.m. to dawn for the next two weeks in about the same location in the sky.

The Perseid shower is one of the longest lasting showers. For tips about optimizing your viewing this year, go to https://earthsky.org/?p=165416  These meteors are sand to pea-sized bits of rock that fell off of Comet Swift-Tuttle. They are traveling about 40 miles per second as they collide with the Earth and burn up in the atmosphere.

The positional information in this column about stars and planets is typically accurate for the entire week. For up-to-date information about the night sky, go to https://nightsky.jpl.nasa.gov/planner.cfm. All times are Pacific Time unless noted.

Tuesday, July 16, 2024

The Ellensburg, WA sky for the week of July 20, 2024

Saturday: Tonight’s full moon is in the constellation Sagittarius. The Wishram, Haida, and Tlingit people of the Pacific Northwest call the July full moon the salmon moon. This is the time of year the salmon return after spawning season.


Sunday: Mercury will be as far away from the Sun in the sky as it will get this orbital cycle. This "farthest away" point is known as the planet's greatest elongation. Since Mercury is in the evening sky, it is east of the Sun so this occurrence is called the greatest eastern elongation. This evening will be the best evening to observe Mercury for the next few weeks. Mercury is nearly a half a fist held upright and at arm’s length above the western horizon at 9:20 p.m. Over the next few weeks, Mercury will move toward the Sun in the sky. By late August, it will be visible in the morning sky.


Monday: Zubenelgenubi, the second brightest star in the constellation Libra. The name means "southern claw", a holdover from the time when this part of the sky was associated with the neighboring constellation of Scorpius the scorpion. Zubenelgenubi is a binary star system, easily seen with binoculars as a white and yellow pair. To a person living on a planet orbiting the dimmer of the two stars, the brighter star would be nearly as bright as the full Moon appears from Earth. Zubenelgenubi is one and a half fists above due southwest at 10:30 p.m.


Tuesday: Saturn is about a fist to the left at 11:30 p.m., about a fist above the east-southeastern horizon.


Wednesday: What you see with the naked eye isn’t all that can be seen. While astronomers can learn a lot from observing the sky in the visible wavelengths, many celestial objects radiate more light, and more information, in wavelengths such as radio, microwave, infrared, ultraviolet, x-ray, and gamma ray. In 2012, NASA launched the Wide-field Infrared Survey Explorer (WISE) to study objects that radiate in the infrared range such as asteroids, cool dim stars, and luminous galaxies. For an interesting comparison of how different wavelengths show different aspects of celestial objects, go to http://goo.gl/nvuax. If it weren’t for infrared telescopes such as WISE, astronomers would not know about the significant amount of dust in galaxies. We also wouldn’t know how much brighter than the Sun red supergiant stars are. Antares is a red supergiant star, currently sitting at one and a half fists above the southern horizon at 9:30 p.m. In the visible wavelengths, Antares shines 10,000 times brighter than the Sun. But since Antares is much cooler than the Sun, its energy distribution peaks in the infrared. So across all wavelengths of light, Antares shines 60,000 times brighter than the Sun. The new James Webb Space telescope is also an infrared telescope.


Thursday: At 4:30 a.m., Jupiter, the brightest point light in the sky at this time, is about two and a half fists above the eastern horizon. Mars is a half a fist to the upper right of Jupiter.


Friday: Let’s learn about Capella. It is the fourth brightest star we can see in Ellensburg. It is the most northerly bright star. It is a binary star consisting of two yellow giant stars that orbit each other every 100 days. At 10:00 p.m., Capella is less than a half a fist above due north. You can also use the Big Dipper to find it.  First, find the two “cap” stars on the cup of the Big Dipper, the stars on the top of the cup. Draw a line from the “cap” star closest to the handle to the cap star farthest from the handle. Then, continue that line to the next very bright star, which is Capella. Thus, you can “cap” to Capella. If you can’t “cap” tonight, don’t worry. Capella is the brightest circumpolar star meaning it is the brightest star that never goes below the horizon from our point of view in Ellensburg.


The positional information in this column about stars and planets is typically accurate for the entire week. For up-to-date information about the night sky, go to https://nightsky.jpl.nasa.gov/planner.cfm. All times are Pacific Time unless noted.


Thursday, July 11, 2024

The Ellensburg, WA sky for the week of July 13, 2024

Saturday: You can see some stars during the day with a small telescope or binoculars. The best candidate today is Spica because it is so close to the moon in the sky. First find the moon, due south at 7:00 p.m. Then aim your small telescope or binoculars at the moon. Spica is to the lower left of the moon. As time passes, the moon slowly moves eastward, to the left, with respect to the background stars. Follow these two objects until about 7:15 p.m. the moon will move between Spica and Earth, blocking it from view. This is called an occultation. By 8:35, Spica will reappear from the right, the lit, side of the moon.

Sunday: Mercury is a half a fist above the west-northwestern horizon at 9:30 p.m.

Monday: Nine years ago today, NASA’s New Horizons probe passed by Pluto. If the band Nirvana were still together, they’d probably rewrite one of their hit songs to be called Heart-Shaped Spot, after one of Pluto’s most distinctive features. “She eyes me like a dwarf planet when I am weak. I’ve been imaging your heart-shaped spot for weeks.” Astronomers think this heart-shaped spot is a large plain of nitrogen ice that consists of convective cells 10-30 miles across. Solid nitrogen is warmed in the interior of Pluto, becomes buoyant, and bubbles up to the surface like a lava lamp. You will find great pictures and information about what New Horizons found this past year at http://pluto.jhuapl.edu/. Pluto, itself, is exactly two fists above due south.

Hey, wait, I’ve got a new complaint. People should be more interested in astronomy. The best group to start with is children. If you are stuck at home, wondering what to do, go to the NASA Kids Club website at https://www.nasa.gov/kidsclub/. There are fun and educational activities for younger children. Older children may like my favorite NASA website about planets outside our Solar System. I suggest first exploring the “Galaxy of Horrors!” at https://exoplanets.nasa.gov/alien-worlds/galaxy-of-horrors/

Tuesday: Saturn is one fist above the east-southeastern horizon at midnight.

Wednesday: Say "Cheese". 174 years ago, Vega, in the constellation Lyra the lyre, became the first star ever photographed. The photograph was taken at the Harvard Observatory using the daguerreotype process. Vega is the third brightest nighttime star we can see in Ellensburg, behind Sirius and Arcturus. Vega is nearly straight overhead at 11:00 tonight.

Thursday: The Southern Delta Aquarid meteor shower has a long gradual peak for the next few weeks into mid-August. Meteor showers are named after the constellation from which the meteors appear to originate. These meteors appear to come from a point in Aquarius near the star Delta Aquarii, also known as Skat. This point is about two and a half fists above the southeast horizon at 3:00 am early this morning. You can follow this point throughout the night and for the next few weeks, as it will remain a fist above Fomalhaut, the brightest star in that section of the sky. Read about the shower, at https://earthsky.org/?p=159138. As your mother might say, dress warm and sit in a comfortable chair for maximum enjoyment. Meteors are tiny rocks that hit the Earth and burn up in the atmosphere.

Friday: Take a two and a half hour walk today. Too long, you say? 55 years ago today, Neil Armstrong and Buzz Aldrin took the first ever walk by humans on another world. They spend two and a half hours setting up scientific instruments and collecting rocks for study back on Earth. Their colleague Michael Collins orbited the Moon in the spacecraft the astronauts would use to return to Earth. While everyone seems to know about Armstrong and Aldrin, spend some time learning more about Collins by reading https://time.com/5624528/michael-collins-apollo-11/.

The positional information in this column about stars and planets is typically accurate for the entire week. For up-to-date information about the night sky, go to https://nightsky.jpl.nasa.gov/planner.cfm. All times are Pacific Time unless noted.


Friday, July 5, 2024

The Ellensburg, WA sky for the week of July 6, 2024

Saturday: Let’s learn about Capella. It is the fourth brightest star we can see in Ellensburg. It is the most northerly bright star. It is a binary star consisting of two yellow giant stars that orbit each other every 100 days. At 11:17 p.m., Capella is a half a fist above due north. You can also use the Big Dipper to find it. First, find the two “cap” stars on the cup of the Big Dipper, the stars on the top of the cup. Draw a line from the “cap” star closest to the handle to the cap star farthest from the handle. Then, continue that line to the next very bright star, which is Capella. Thus, you can “cap” to Capella. If you can’t “cap” tonight, don’t worry. Capella is the brightest circumpolar star meaning it is the brightest star that never goes below the horizon from our point of view in Ellensburg.

Sunday: Mercury is less than a half a fist to the lower right of the waxing crescent moon at 9:30 p.m. They are low in the west-northwestern sky.

Monday: Saturn is a half a fist above the eastern horizon at 12:15 a.m.

Tuesday: Antares is about a fist and a half above due south at 10:16 p.m.

Wednesday: About nine years ago astronomers using a radio telescope in Australia discovered the source of fleeting radio signal bursts that had been a mystery for 17 years. And they didn’t have to probe the depths of deep space. They only had to probe the depths of… the observatory kitchen. It turns out the signal came from opening the microwave door prematurely. Read more about The Microwave Emission here: http://goo.gl/Ftb04C. Sheldon Cooper used similar methods of science when he discovered a can opener instead of magnetic monopoles in the season three premiere of “The Big Bang Theory” http://goo.gl/kAEoOD.

Thursday: Two years ago, the Mars Curiosity rover made a comprehensive measurement of the organic carbon found in rocks on the Martian surface. It found more organic carbon in the Gale Crater rocks than in very low-life places on Earth such as the Atacama Desert in South America. This certainly does not prove there is life on Mars now. And it does not prove there was life on Mars in the past. But it strengthens the argument for either. In the past, Gale Crater likely had water, chemical energy sources, low acidity, and other elements common in living organisms. Read more about the findings at https://www.nasa.gov/feature/goddard/2022/mars-total-organic-carbon. Mars is two and a half fists above due east at 4:30 a.m. Very bright Jupiter is to the lower left of Mars.

Friday: Stonehenge was created on the island of Great Britain by Neolithic people. “Manhattanhenge” was created on the island of Manhattan by modern day architects and construction workers. Twice a year, the end of May and mid-July, the setting Sun aligns perfectly with the Manhattan grid pattern. That means observers will see the Sun set at the end of the street. The first Manhattanhenge sunset of July is tonight at 8:20 p.m. Eastern time and then again tomorrow at 8:21 p.m. Eastern time. For more information about Manhattanhenge, go to https://www.amnh.org/research/hayden-planetarium/manhattanhenge.

The positional information in this column about stars and planets is typically accurate for the entire week. For up-to-date information about the night sky, go to https://nightsky.jpl.nasa.gov/planner.cfm. All times are Pacific Time unless noted.