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What's that bright light in the night sky?

Below are descriptions of some of the bright moving objects you might encounter in the night sky. Record the time you saw an object and the hyperlinks below will take you to records on the wonderful Heavens-above website of when the identified object should have passed over and when it is likely to be seen again (click on Next and Prev to check other dates when you are on the Heavens-above website).

Is the body you are observing...
..Slow Moving
- Satellites
- Int. Space Station
- Space Shuttle
(click here)
..Fast Moving
- Meteors
- Fireballs
(click here)

 

Slow moving bodies

Normal satellites - Watch the night sky for enough time and you'll be able to see a tiny spot of light slowly track across the sky. These are rarely much brighter than an average star. These are satellites, and can be as little as much as ~40,000 km above the Earth for the TV, telephone and data satellites!! These track at a constant rate and light intensity for a long distance, and may take a minute or so to cross the entire sky.

International Space Station - The International Space Station can be seen from Earth when its large solar panels reflect the sun back to earth at night. It's more than 334-348 km above your head! When will it next pass visibly over Fredericton? Find out here. The Space shuttle also travels at about 300 km above the Earth's surface when it is in orbit, unless it is going to meet the Space Station.

Iridium Satellites - The Iridium satellites are a set of communication satellites used for global satellite phones. They have large solar panels that can reflect the sun back down to earth at night when they are in just the right orientation. These appear as slow moving points of light that get gradually brighter and then dimmer. They move slower than meteors and fireballs and tend to have short tracks.

Planes! - If the light is flashing, it is likely a plane!

Fast moving bodies

Meteors - Meteors are produced when grains of sand-sized material burns up in our atmosphere. This material includes rocky dust particles and cometary debris. A meteor shower occurs when the Earth's orbit takes it through the debris left behind from the passage of an ancient comet. This is why meteor showers tend to occur at certain times of the year: at those times of year the Earth passes through the same trail of comet junk.

Here are the dates and estimated hourly rates of some of the major showers:

2010 Meteor Showers
Shower
Radiant and
direction

Morning of
maximum

Hourly rate
Quadrantid*
Draco (NE)
Jan. 3-4
120
Eta Aquarid*
Aquarius (E)
May 5-6
70
Delta Aquarid
Aquarius (S)
July 30
15
Perseus (NE)
Aug. 12-13
30-50

Leonid

Leo (E)
Nov. 17
20+
Geminid
Gemini (S)
Dec. 13-14
120

2011 Meteor Showers
Shower Activity Maximum       Max Hourly Rate
Date        
Antihelion Source (ANT) Nov 26 - Sep 24 March-April,       4
late May, late June
Quadrantids (QUA) Dec 28 - Jan 12 Jan 04           120
α-Centaurids (ACE) Jan 28 - Feb 21 Feb 08           6
γ-Normids (GNO) Feb 25 - Mar 22 Mar 15           6
Lyrids (LYR) Apr 16 - Apr 25 Apr 22           18
π-Puppids (PPU) Apr 15 - Apr 28 Apr 24           Var
η-Aquariids (ETA) Apr 19 - May 28 May 06           70
η-Lyrids (ELY) May 03 - May 14 May 09           3
June Bootids (JBO) Jun 22 - Jul 02 Jun 27           Var
Piscis Austrinids (PAU) Jul 15 - Aug 10 Jul 28           5
South. δ-Aquariids (SDA) Jul 12 - Aug 23 Jul 30           16
α-Capricornids (CAP) Jul 03 - Aug 15 Jul 30           5
Perseids (PER)* Jul 17 - Aug 24 Aug 13           100
κ-Cygnids (KCG) Aug 03 - Aug 25 Aug 18             3
α-Aurigids (AUR) Aug 28 - Sep 10 Sep 01           6
September ε-Perseids (SPE) Sep 05 - Sep 21 Sep 10           5
δ-Aurigids (DAU) Oct 10 - Oct 18 Oct 12           2
Draconids (DRA) Oct 06 - Oct 10 Oct 08           Var
Southern Taurids (STA) Sep 10 - Nov 20 Oct 10           5
ε-Geminids (EGE) Oct 14 - Oct 27 Oct 18           3
Orionids (ORI) Oct 02 - Nov 07 Oct 21           25
Leo Minorids (LMI) Oct 19 - Oct 27 Oct 24           2
Northern Taurids (NTA) Oct 20 - Dec 10 Nov 12           5
Leonids (LEO) Nov 06 - Nov 30 Nov 18           20+
α-Monocerotids (AMO) Nov 15 - Nov 25 Nov 22           Var
Phoenicids (PHO) Nov 28 - Dec 09 Dec 06           Var
Puppid-Velids (PUP) Dec 01 - Dec 15 (Dec 07)           10
Monocerotids (MON) Nov 27 - Dec 17 Dec 09           2
σ-Hydrids (HYD) Dec 03 - Dec 15 Dec 12           3
Geminids (GEM) Dec 07 - Dec 17 Dec 14           120
Dec. Leonis Minorids (DLM) Dec 05 - Feb 04 Dec 20           5
Comae Berenicids (COM) Dec 12 - Dec 23 Dec 16           3
Ursids (URS) Dec 17 - Dec 26 Dec 23           10

 

Fireballs - Fireballs are bright meteors. The distinction between a meteor and fireball is somewhat arbitrary - though fireballs are always generated by larger chunks of rock (meteoroids) passing through the atmopshere. These are significant, because they may make it all the way through their fiery passage in the atmosphere and make it to the ground, where they are called meteorites.

Fireballs often change in brightness and can become very bright as fragments break off or when the meteoroid actually breaks into pieces. This can occasionally be accompanied by sound, as the shock wave generated by the break-up passes through the atmosphere and reaches the ground. The sound will always occur after the bright flash because sound travels slower to the ground than does the light from the flash. The delay can be used to define how far away the fireball actually is from the observer, in a similar way that the delay between seeing lightening and hearing thunder can define the distance to a storm.

You won't find fireballs on the Heavens-above website because they don't occur at predictable times - it all depends on when random pieces of meteoroid enter the atmopshere.

What does the night sky look like today over Fredericton? Find out here

 

November 13, 2013