I mentioned the Starlink satellite constellation to students in my after-school astronomy and space science club, and afterwards got into a discussion about space junk. I told the students that when I was their age, there were only a handful of man-made objects in Earth orbit. Today, there are thousands of objects in orbit – some useful, many not so much. Many satellites and space probes require multi-stage rockets to get them into orbit and/or to their destination. When a rocket stage is spent, it decouples – and continues in whatever orbit the vessel was currently in at that moment. If the vessel was in a sub-orbital trajectory, the spent stage either burns up, or is guided back to a safe landing – as has been known to happen. If the vessel was in orbit at the moment of decoupling, the spent stage remains in that orbit, becoming space debris. When a satellite or space probe has reached the end … Continue reading →
About Bob Trembley
Bob is a lifelong amateur astronomer, and the 2019 outreach officer for the Warren Astronomical Society, and a volunteer NASA/JPL Solar System Ambassador. Bob does a lot of astronomy outreach - he lectures about astronomy and space science, and sets up his telescopes at schools, planetariums, conventions, and other venues. From 2014-2016, he was the editor of the Warren Astronomical Society's newsletter.
Bob is fantastically interested in asteroids and near-Earth objects (NEOs), and a HUGE fan of Kerbal Space Program; he is determined to improve the teaching of astronomy and Space History throughout Michigan, and the U.S. Follow Bob on Twitter, Facebook, The Web, and YouTube.
At last night’s meeting of the Warren Astronomical Society, the topic of the Starlink satellite constellation came up during the “In the News” segment, and a groan of dismay could be heard from the entire audience. If you are unfamiliar with Starlink, it is a constellation of potentially tens of thousands of communication satellites created by SpaceX with the goal of providing global high-speed internet – that concept sounds great! Starlink satellites during a meteor shower on Nov. 22. pic.twitter.com/wJVk1qu49E — Patrick Treuthardt, Ph.D. (@PTreuthardt) November 25, 2019 The first time I became aware of Starlink was after the 2nd satellite deployment mission of May of 2019, when 60 satellites were put into a 53° Earth orbit. Almost immediately satellite sightings started pouring in from around the world. Videos show a long trail of lights traversing the sky, virtually painting the orbits of the satellites in your mind’s eye, and literally painting them in the cameras of astronomers and astrophotographers … Continue reading →
Last week I had students in my after-school astronomy and space science club build and fly rockets in Kerbal Space Program. I had them launch and recover a small pre-made rocket, and build-from-scratch a sub-orbital crewed rocket, similar to a Mercury Redstone. The very next day, I gave the “In the News” report at the meeting of the Warren Astronomical Society – I shamelessly pulled material from my previous “In the Sky” post; I included a slide about the Europa Clipper mission, and a couple about mid-ocean rift ecosystems and extremophiles. There will be a conjunction of Venus and Jupiter low on the southwestern horizon all week; Saturn continues to appear high above the southwestern horizon, and makes for an excellent observing target after Jupiter and Venus have set. Kerbal Space Program has been posting bits of astronomy news and space history on their social media feeds lately – I approve! There's a Venus & Jupiter conjunction on Nov 24th. A conjunction … Continue reading →
In last week’s session of my after-school club, the Endeavour Space Academy, I ran the students through a very quick tour of the solar system using both NASA’s Eyes on the Solar System app, and the NASA Solar System Exploration website. Only a couple of the students knew anything at all about the solar system, so I covered the most important points in the 25 minutes available… I wish I had several more hours to cover everything! I asked the students if any of them knew about the Earth’s mid-ocean rifts – one said they were covering that in science class. I asked the student if she heard about the ecosystems that exist around the mid-ocean rifts, and extremophiles? I talked about the students about the possibility that similar sub-ocean rift systems might exist on several of the icy moons in the outer solar system, and what that might mean for the search for life. Saturn appears high above the … Continue reading →
I hope you had better luck than I did seeing the transit of Mercury… a good portion of North America was shrouded in clouds – I got several inches of snow! Even the website I pointed readers to last week to view the transit online was not broadcasting due to clouds. I ended up watching it on NASA’s Solar Dynamics Observatory’s (SDO) Eclipse website – clouds are never a problem for the SDO. Venus and Jupiter appear very low and Saturn appears high in the southwestern sky after sunset this week over the week. Jupiter moves slightly towards the horizon, and Venus moves slightly southward toward Jupiter. By the beginning of next week Mercury returns, appearing low and Mars a bit higher above the eastern horizon before sunrise this week. If you are having trouble spotting Mercury, you can use Mars and the star Spica to star-hop in the general direction of Mercury. The Moon appears high in the sky at … Continue reading →
Jupiter is low on the horizon, and Saturn is high in the southwestern sky after sunset this week. Mars appears low in the eastern sky just before sunrise. The Moon appears in the south-southeastern sky after sunset this week – going from first quarter, to a waxing gibbous, to full early next week. The full Moon appears high in the southeastern sky above the constellation Orion at 10:00 PM on Nov. 11th. The Pleiades star cluster (M 45) and the constellation Taurus with the bright red star Aldebaran appear nearly overhead at midnight all week. Venus appears low on the southwestern horizon after sunset Transit of Mercury Transits occur when a planet or another body moves in between another distant body and an observer; transits of our Sun are rare and fascinating astronomical events, and one is happening on November 11, 2019 from 7:36 AM-1:04 PM EST! You will need a telescope to see Mercury cross the face of … Continue reading →
The Moon appears near both Jupiter and Saturn this week in the southwestern sky at dusk. Saturn and Jupiter are excellent observing targets; Jupiter is getting lower towards the horizon each evening, and will be lost in the glare of the Sun in early December. Note: This region of the sky will have a conjunction of the Moon, Jupiter, Saturn and Venus in late November – stay tuned! Mars appears low in the eastern sky just before sunrise. The Moon joins Venus and Mercury low on the southwestern sky at dusk on Oct. 29th – Mercury may be challenging to see. See if you can catch a glimpse of earthshine on the Moon for the next couple evenings. The constellation Ursa Major and the very familiar “Big Dipper” asterism appear in the north-northwestern sky a few hours after sunset this week We get a LOT of clouds here in Michigan, and thunderstorms are not unusual; I saw this article on … Continue reading →
Saturn and Jupiter continue to be excellent observing targets in the southern sky after sunset; this last weekend. The Warren Astronomical Society hosted a boatload of girl and boy scouts at their Stargate Observatory this last weekend – I was with the girl scouts before dusk showing them a virtual reality fly-over of Saturn, another member was talking to the girls about meteorites. Mars appears low in the eastern sky just before sunrise. The Moon passes through the constellations Cancer and Leo in the mornings of Oct. 22-24th. A very VERY thin waning crescent Moon appears near to Mars above the eastern horizon before dawn on Oct. 26th. Venus and Mercury appear very close to each other in the southwestern sky at dusk on Oct. 22nd – if you use binoculars, and get Venus in your right field-of-view, Mercury will be in your left. Observing this may be a challenge if you have anything obscuring your view of the horizon. … Continue reading →
Saturn and Jupiter are excellent observing targets all week after sunset – Jupiter is getting lower towards the horizon each evening. I’m also noting that it’s getting darker earlier each evening. The Moon appears in the predawn sky this week, moving from west to east; the waning gibbous Moon appears high in the western sky before sunrise on Oct. 15 & 16th. On Oct. 17 and 18th, the waning gibbous Moon appears near the star Aldebaran in the southwestern predawn sky. The third-quarter Moon appears high in the southern predawn sky near the star Pollux on Oct. 21st. Mars appears low in the eastern sky just before sunrise. Orion was again impossible to miss high in the southern predawn sky. Betelgeuse Betelgeuse is generally the ninth-brightest star in the night sky and second-brightest in the constellation of Orion (after Rigel). It is a distinctly reddish, semiregular variable star whose apparent magnitude varies between +0.0 and +1.3, the widest range of any first-magnitude star. At near-infrared wavelengths, Betelgeuse is the brightest star in the night sky. It has the Bayer … Continue reading →
I started off our last club meeting by showing my “In the Sky” post I’d written the day before – hey… why not!? Several of the students said that they had seen Ursa Major, and a couple said they could see the Mizar/Alcor double star! This week’s constellation was Cassiopeia; I showed the students where to find the constellation, and some deep-sky objects in the Cassiopeia, including the open cluster M103. I discussed the differences between open and globular star clusters, and showed a few examples of each. We discussed galaxy mergers, and I showed this animation of galaxy mergers seen from different perspectives: We then discussed how the Andromeda galaxy and the Milky Way will collide in several billion years; I showed this PBS video about the collision: During the video, one of the students asked my wife “What is that band of stars behind the narrator?” I stopped the video, and brought up a photo of the Milky Way … Continue reading →
This week is World Space Week! Held annually every October 4-10th, it is the largest space event on Earth, with more than 5,000 events in over 80 countries. The theme for 2019 is: “The Moon: Gateway to the Stars.” “The General Assembly declares 4 to 10 October World Space Week to celebrate each year at the international level the contributions of space science and technology to the betterment of the human condition” – UN General Assembly resolution, 6 December 1999 Saturn, Jupiter and the Moon continue to be excellent observing targets all week after sunset. The waxing gibbous Moon is in the southwestern sky at midnight on Oct. 8th. At midnight on Oct. 11th, the waxing gibbous Moon is high in the southern sky. The full Moon appears in the southeastern sky at midnight, Oct. 14th. Mars appears a bit higher each morning in the eastern sky just before sunrise. Constellation Pegasus Pegasus is a constellation in the northern sky, named after … Continue reading →
The International Space Station will be visible four times over southeastern Michigan shortly after sunset from Oct.7-10, 2019. Fly-over info from Heavens-Above.com (from my driveway in Chesterfield, MI): Date Brightness Start Highest point End Pass type (mag) Time Alt. Az. Time Alt. Az. Time Alt. Az. 07 Oct -2.6 20:46:34 10° WNW 20:49:38 35° SW 20:50:12 32° SSW visible 08 Oct -3.4 19:57:52 10° WNW 20:01:10 62° SW 20:03:59 13° SE visible 09 Oct -0.9 20:47:14 10° W 20:48:55 13° SW 20:50:37 10° SSW visible 10 Oct -1.5 19:57:51 10° W 20:00:32 22° SW 20:03:11 10° S visible You can find and chart exact times for several different satellite fly-overs from your location on the Heavens-Above.com website. ISS News: .@Astro_Christina and @AstroDrewMorgan successfully wrapped up a seven-hour and one minute spacewalk today beginning the work to upgrade the station's power systems this month. Read more… https://t.co/J1ZplaY8Ex pic.twitter.com/r6M9Zm8zEw — Intl. Space Station (@Space_Station) October 6, 2019Continue reading →