Credit: Event Horizon Telescope Collaboration
Wednesday 10 April 2019 was a big day for the astronomy community. Information was presented from the Event Horizon Telescope (EHT) project revealing new details about the super-massive black hole in galaxy M-87. The intent of this post is to offer some perspective helpful to those who are not experts in this field.
Prior to the news release, I read a very comprehensive and helpful blog post by physicist Matt Strassler. His post addressed questions that were likely to be asked by the non-expert about the significance and details of the announcement. Some points he made were useful in the writing of this post.
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The brightest star in the night sky is Sirius in the constellation Canis Major to the lower left of Orion. It is bright in the southeast evening sky at this time of year. Follow the three bright stars of Orion’s belt to the lower left and find Sirius.
I wondered if I could see Sirius in the daytime. On two occasions this week, I looked for Sirius with my 15x binoculars. They binoculars are heavy but steadied with my custom support. Both times I was able to see it shining brightly in bright daylight. This is a first for me.
If you are interested in trying this yourself, here are some details. Sunset is just after 7:15 pm locally. The time of viewing Sirius was about 6:15 pm CDT with very clear sky. It was at 150˚ azimuth (east is 90˚ south is 180˚) and was about 26˚ altitude. I have a small app on my Android phone called Protractor that helped determine the altitude. Give it a try.
🔭 Updates an earlier post to include recent changes and new information. 🔭
Desktop planetarium software helps plan viewing sessions and keep track of the planets and Moon. Many products are available for all computer platforms and smartphones. A Google search yields links to many sources. Open source and free Stellarium is on my desktop computer. It can be customized to your location and has a nice look and feel. For Android and Mac phones and tablets, I like SkySafari. It isn’t free but is inexpensive.
Online planetarium sites are popular and offer many features. Below are highlights of a few I like. With multiple features, a unique look and feel, and different levels of detail, they can help satisfy your curiosity about astronomical events. I welcome reader questions or reviews about using these tools or others you find helpful.
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How will the Moon look on any date in 2019? What will it look like on your birthday? Find out at NASA Dial-a-Moon. Here is Dial-a-Moon for southern hemisphere readers.
8 Feb 2019
Enter any month and day to see a high definition image. The composite images of Dial-a-Moon are made from those of the Lunar Reconnaissance Orbiter (LRO) in low altitude orbit around the Moon since 2009.
You may leave the universal time (UT) at the default value. Your local to Universal time conversion can be done at this link. Or, type ‘universal time’ into Google. Go back to Dial-a-Moon to enter the UT.
A Year of Moon Motions
The collection of accurate images of the Moon for each hour have been made into the movies below each lasting about 5 minutes. Try watching full screen for the best effect. Versions of the movie are available for readers in the northern and the southern hemispheres.
I explain the Moon’s peculiar wobble and tipping motions at this blog post.
The New Horizons spacecraft returned this detailed image of Ultima Thule to Earth on 18-19 Jan 2018. It was captured 7 minutes before the closest approach to Ultima Thule at a distance of 4,200 mi (6,700 km). The signal of digital bits traveled at the speed of light for 6 hrs before reaching the antenna at Earth so we could see it.
The shape of Ultima Thule was discovered in July 2017 when it passed in front of a distant star as seen from Earth. Twenty four telescopes were lined up across Argentina where the shadow of Ultima Thule was to pass as it occulted the distant star. The scopes were coordinated with precise time markers. The best-fit of their timings suggested a bi-lobed object. What an amazing prediction considering UT is only about 20 mi (30 km) across and measured from more than 4 billion miles away.
This is probably the oldest and most primordial object we will ever see in such detail.
Ultima Thule belongs to a class of Kuiper belt objects called the “Cold Classicals,” which have nearly circular orbits with low inclinations to the solar plane, and which have not been perturbed since their formation perhaps 4.6 billion years ago. Ultima Thule will therefore be the most primitive planetary object yet explored, and will reveal to us what conditions were like in this distant part of the solar system as it condensed from the solar nebula.
What’s next for New Horizons? Hopes are high for extensions to the mission into 2019 and beyond. It will take into 2020 to download all the data stored in the memory banks. With remaining fuel, New Horizons might survey the field ahead and redirect slightly to pass by other Kuiper Belt objects. Stay tuned to see what might happen.
I really like my Celestron Skymaster Pro 15×70 mm binoculars. Their wide field of view, bright optics, and sharp focus enhance views of the night sky. What I don’t like is how heavy they are at 3.75 lbs (1.70 kg). They came with a tripod mount which works fine. But, I have found getting into good viewing position to look steeply up in the sky can be a challenge. The tripod legs are extended too far if I am standing which adds to it shaking. Sitting to view doesn’t work better as the tripod and my legs compete for the same space.
I wondered if there was a better and cheap solution to holding the binoculars steady and giving me flexibility for viewing. I browsed the local hardware store for inspiration and found this tool in the paint section. The tool had a swivel head with about 60˚range of motion.
In a display of extendable poles, I picked one that was a bit taller than me in its longest position. Total cost was $20.
The binoculars rest firmly on the foam pad of the paint tool with enough friction so they don’t slip. A small bungee cord might be a good idea. I can easily grip them and the pad and adjust focus if necessary. The adjustable pole gives comfortable and very stable control of height. I can tilt up-down and right-left easily to scan a portion of sky. Set up and take down is fast. Best of all, no more shaky binoculars. This is a winner for me.
Update: Second date of views (4 Jan 2019) is at the bottom of this post.
The largest asteroid Ceres has been orbited by the ion-engine powered DAWN spacecraft since early 2015. DAWN ran out of fuel to maneuver in October 2018 and will remain silent in orbit at Ceres for decades. Previous to Ceres, it visited the second largest asteroid Vesta. This fly-over video gives a close view of Ceres.
The asteroid is far away and quite small and dim. It is not something most people have ever seen with the naked eye or in a telescope. I’ve been tracking Ceres with desktop planetarium software with hopes to see it. I am happy to report success.
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