Here are this week’s best astronomical events that you can view right from your backyard. Below is a picture of the Pleiades open star cluster, better known as the Seven Sisters. There’s a great viewing opportunity of it on Wednesday of this week. And there’s a few other viewing opportunities for the Taurid and Leonid meteor showers on Monday and Tuesday as well. With so many neat astronomy events this week, I’d love to know what you see. Happy exploring!
Second star to the right and straight on ’til morning. –J.M. Barrie, Peter Pan
You can use the star chart provided here. And for any terms or units you may be unfamiliar with, I’ve provided a glossary at the end of the guide for your convenience. All events were calculated based on Boulder, CO (latitude 40⁰ N), but should provide good approximations for most cities near the same latitude. If you would like, you can change your location on the linked sites for each event. Let me know if you have any questions. I’d love to know what you see this week!
Thursday 11/12
24:00 MST Taurid Meteor Shower
The Taurid meteor shower will reach its peak activity tonight. Shooting stars associated with the shower should be visible from October 20th through November 30th. The maximum rate of visible meteors is expected to reach 10 per hour; however, this zenithal hourly rate is dependent on many factors, such as sky conditions, light pollution at the observer’s location, and altitude of the meteor shower’s radiant in the sky. The Moon will be 1 day old at the peak, and so will present minimal interference. At midnight, the shower’s radiant will appear 71⁰ above the southern horizon, with the meteors traveling directly outward from this point. In order to see the most meteors possible, it is best to look at any dark patch of sky 90⁰ around the radiant, rather than at the radiant itself. This is because the meteors will typically appear brightest at these locations. It is so named the Taurid meteor shower because of its radiant’s location with the constellation Taurus. More information here.
Friday 11/13
05:22 MDT ISS Passing
The ISS will make a visible pass (magnitude -1.1) starting at 13⁰ elevation in the NNW and moving NNE. More information here.
23:32 MST Moon at Perihelion
The Moon will reach its closest point in its orbit to the Sun, at a distance of 0.9872 AU. The Moon will lie between the Sun and the Earth at this time. For comparison, the Earth will be at a distance of 0.9971 AU from the Sun. More information here.
Saturday 11/14
17:36 MST Iridium Flare (Iridium 22)
The Iridium 22 satellite will cause an iridium flare of magnitude -3.2 that will be seen as a bright flash across the sky. The flare will begin at an elevation of 35⁰ in the South. More information here.
Sunday 11/15
17:30 MST Iridium Flare (Iridium 25)
The Iridium 25 satellite will cause an iridium flare of magnitude -3.8 that will be seen as a bright flash across the sky. The flare will begin at an elevation of 35⁰ in the South. More information here.
Monday 11/16
05:48 MST Iridium Flare (Iridium 3)
The Iridium 3 satellite will cause an iridium flare of magnitude -3.9 that will be seen as a bright flash across the sky. The flare will begin at an elevation of 54⁰ in the North. More information here.
Tuesday 11/17
05:42 MST Iridium Flare (Iridium 76)
The Iridium 76 satellite will cause an iridium flare of magnitude -3.1 that will be seen as a bright flash across the sky. The flare will begin at an elevation of 53⁰ in the North. More information here.
07:35 MST Mercury at Superior Solar Conjunction
Mercury and the Sun will be very close (as viewed from Earth), passing within 0⁰14’ of each other. This will make Mercury unobservable for several weeks while it is lost in the Sun’s glare. During this time, Mercury will also reach apogee, the point in its orbit farthest from Earth. It will lie at a distance of 1.45 AU from the Earth, making it appear very small in the sky (~4.7 arcsec in diameter). Mercury’s superior conjunctions marks the end of its appearance in the morning sky. It will now be visible in the evening sky over the next few weeks. More information here.
24:00 MST Leonid Meteor Shower
The Leonid meteor shower will reach its peak activity tonight. Shooting stars associated with the shower should be visible from November 15th through November 20th. The maximum rate of visible meteors is expected to reach 20 per hour; however, this zenithal hourly rate is dependent on many factors, such as sky conditions, light pollution at the observer’s location, and altitude of the meteor shower’s radiant in the sky. The Moon will be 7 days old at the peak, and so will present significant interference in the early evening sky. At midnight, the shower’s radiant will appear 13⁰ above the eastern horizon, with the meteors traveling directly outward from this point. In order to see the most meteors possible, it is best to look at any dark patch of sky 90⁰ around the radiant, rather than at the radiant itself. This is because the meteors will typically appear brightest at these locations. It is so named the Leonid meteor shower because of its radiant’s location with the constellation Leo. More information here.
Wednesday 11/18
17:49 MST M45 is well placed
The Pleiades open star cluster M45 (also here) will be placed for observation in the constellation Taurus. From Boulder, M45 will become visible around 17:48 MST as it rises 12⁰ above the eastern horizon. It will reach its highest point around midnight at an elevation of 74⁰ above the southern horizon. It will be lost to dawn twilight around 06:06:15 MST when it is 15⁰ above the western horizon. At a magnitude of 1.6, M45 is visible to the naked eye, but is best viewed through binoculars. More information here.
Glossary
Apogee: The point in the orbit farthest away from the Earth.
Apehelion: The point in the orbit farthest away from the Sun.
Arcminute: An angular measurement, defined as 1/60 of one degree. Denoted by ‘. (approx. 1 inch at a distance of 100 yards, the Moon is approx 31’)
Arcsecond: An angular measurement, defined as 1/60 of an arcminute. Denoted by “. (approx. dime at a distance of 1 mile )
A great resource for understanding and approximating angular measurements in the night sky, here. The Moon is approx 1/2⁰. Your outstretched hand is approx 20⁰, with each finger approx 1⁰. Your closed outstretched palm is approx 10⁰.
AU: Astronomical Unit, Defined as the distance between the Sun and Earth.
Conjunction: An alignment of two celestial bodies such that they present the least angular separation as viewed from Earth.
Elongation: The angle between the Sun and a planet, with Earth as the reference point. The greatest elongation of a planet occurs when this separation angle is at its largest. More information here.
Iridium Flare: Iridium fares occur when sunlight is reflected off the antenna (of one of the 66 active telecommunication sats in LEO, known as the Iridium constellation) directly down at Earth. This reflection causes an illuminated spot on the surface of the Earth. To an observer on the ground, the event appears to be a bright flash, or flare in the sky, which lasts for a few seconds.
ISS: International Space Station. More information here.
Magnitude: A logarithmic measure of the brightness of an object. Brighter objects have a lower (more negative) magnitude. More information here.
Opposition: When a celestial body is opposite the Sun in the sky.
Perigee: The point in the orbit closet to the Earth.
Perihelion: The point in the orbit closest to the Sun.
Radiant: The point in the sky where meteors of a meteor shower appear to originate.
Time Conversions from MST
Eastern Daylight Time, EST = MST + 2:00
Central Daylight Time, CST = MST + 1:00
Mountain Daylight Time, MST
Pacific Daylight Time, PST = MST – 1:00
Alaska Daylight Time, AKST = MST – 2:00
The standard for astronomical times is UTC if you happen to come across it, where MST = UTC – 6:00.
No Comments