Nova Eridani 2009

This is my second nova photo, and my first one done telescopically. Nova Eridani 2009 is not especially bright, but at 8th magnitude it is an easy target and far brighter than any of its neighbors. About 20 days earlier, at maximum light, the nova had been about 6th magnitude. Prior to the outburst there was a 15th mag star at this location. That would be too faint to show up in the relatively shallow image shown here.
(40x10sec ISO 1600 2x telextender, 2009/12/04 05:15 UT)

Remarkable Stars

UV Ceti	Cygnus X-1

UV Ceti is actually a binary system composed of two nearly equal red dwarfs (mag. = 12). The stars are about 1/10 the mass of the sun, 1/7 the radius, and only 1/20000 as bright as the sun. The fainter secondary, UB Ceti B, is famous for being a flare star. It can brighten by several magnitudes in just a few minutes. Flares on the sun have no significant impact on its visible brightness. But when a similarly strong flare occurs on a far less luminous M dwarf, the change in brightness can be dramatic. Unfortunately, I saw no evidence of a flare in the sequence of photos I took. The primary, UV Ceti A, is also a flare star, but with weaker activity. The UV Ceti system is one of the Sun's nearest neighbors, and has a high proper motion which can easily be tracked from year to year.
Cygnus X-1 is also a binary system. It's about as different from UV Ceti as can be. The visible star (mag. = 8.9) in the system is a massive O star: about 30 times the mass of the sun, 20 times the radius of the sun, and 300000 times the luminosity of the sun. The companion is a 9 solar mass black hole. The black hole itself emits no light. However, the O star dumps matter into the gravitation well of the black hole. The material orbits in an accretion disk that gets heated to extremely high temperatures before it crosses through the event horizon of the black hole. This hot accretion disk emits a prodigious amount of X-rays, making Cygnus X-1 one of the brightest X-ray sources in the sky.
(71,23x32 sec ISO 1600 2x telextender, 11/7/09)

Double Stars on a Cloudy Night

ε Lyr

ζ Lyr β Lyr

η Lyr WDS 19135+3902

β Cyg δ Cyg

A typical summer night with lots of humidity and thick high cirrus is not good for deep sky imaging, but still works for double stars... at least until you can't see any stars at all anymore. The scale of all these pictures is the same, but in some cases the exposure times are a bit different. I like that ε Lyr can be resolved at this scale. I was surprised to find that ζ Lyr and β Lyr are practically twins. The WDS (Washington Double Star Catalog) star was coincidentally in the same field as η Lyr (click on either image to see both). β Cyg is here just because it's the Orion Nebula of double stars (if you know what I mean). δ Cyg is a bit iffy, but I think this is real. All these stars were selected from the relevant double star list between the maps in Norton's Star Atlas.

A Very Deep Image of Polaris

As I was setting up a sharp-edge blanket of think cirrus clouds were sliding up from the south. I figured that I might as well just take some pictures of Polaris, because it would remain visible longer than anything else. Surprisingly the line of clouds stopped just short of covering Polaris, and then slid away back to the south. Though by then it was getting too late to do much of anything else. In this (logarithmically scaled) version of the image you can still see the fainter companion star, Polaris B. In the linked image (linearly scaled), Polaris B is lost in the glare, but a faint galaxy north of Polaris is marginally visible. This is not such a small faint galaxy (not when I can image it), but apparently it's generally been neglected because of its proximity to Polaris and/or the North Celestial Pole. The first note of the galaxy seems to be as an infrared source: IRAS 01476+8906. It was later noted in the 2MASS (near-infrared) and NVSS (radio) surveys. (60x30sec+10x30sec dark frames, ISO 1600, 2x Telextender + 6" scope, Canon EOS Rebel XS; 2009/07/08)

Motion, Picture, Star

All the stars in the sky are in motion. Despite speeds of tens to hundreds of km/s, their apparent motions are tiny because the distances involved are so large. Presently, Barnard's Star exhibits the highest proper motion of any star in the sky. This set of images shows the 10.3" annual motion of Barnard's Star over a 4 year interval. The later pictures are deeper than the others because my switch to the 6" scope and new mount (and then a new camera too) makes it easy to get much deeper (and more interesting) images. (2005/06/27 and 2006/06/17 12x4sec ISO 400; 2007/06/22 10x8sec ISO 400; 2008/07/03 5x32sec ISO 400, 6" scope; 2009/07/04 12x20sec ISO 1600, 6" scope)

Siriusly Bright

R And, R Cas

A pair of long-period variable stars. I had no idea what phase these stars were at, but I suspected I would find them to be very distinctly red regardless. (5x64sec ISO 400 exposures, 25mm eyepiece 6" telescope. 2008/10/30)

Cassiopeia

α	β	γ
δ	ε	ζ
η	θ	ι

η Cas (AB sep. = 12.9"; 3.5+7.5 mag.; 3x0.5sec images; 4x zoom, 12.5mm eyepiece)
ι Cas (AB sep. = 2.5", AC sep. = 7.2"; 4.6+6.9+8.4 mag.; 6x0.25sec images; 4x zoom, 12.5mm eyepiece)
An impromptu project for a full-moonlit night. Cassiopeia was not very high, but was in the the darkest available portion of the sky. (2x16sec ISO 200 images; 4x zoom; 25 mm eyepiece; mouseover images of the multiple stars η and ι are from the following night with 12.5 mm eyepiece).

Bright Star Test Images

Deneb (α Cyg: 1.3 mag.; 1x64sec images; 4x zoom)
Albireo (β Cyg: AB sep. = 34"; 3.0 + 5.1 mag.; 4x24sec images; 4x zoom),
Polaris (α UMi: AB sep. = 18", 2.0v + 8.2 mag.; 5x8sec images).
These images were intended to show the diffraction spikes around bright stars. For Albireo, in particular, I was hoping to get diffraction spikes of two different colors. The linked GIF of Deneb shows deep images before and after cleaning the secondary mirror and recollimating the optics. It worked: there seems to be a reduction in the scattered light, and the doubled diffraction spike is now single.

Two pair and more

β Lyr (AB sep. = 45"; 3.4 + 6.7 mag.; 1x32sec images; 4x zoom) (linked image = 1x64sec)
ν Sco (sep. = 41" 1.3" 2.4"; (4.3+6.8)+(6.4+7.8) mag.; ?x1/15sec images; 4x zoom, 12.5mm? eyepiece)

The β Lyr image was just a single deep image for fun. There are always fainter stars in the field of nice doubles if you just look deep enough.
The ν Sco image was a dedicated effort to capture this difficult double double star. The brighter pair of stars is not quite resolved here.

γ Vir and γ Leo

γ Vir, also known as Porrima, is a binary star with a period of 169.101 yr. The orbit is highly elliptical, with periastron occurring in mid 2005. At that time the stars were <1" apart and too close for me to split. Since then they've been moving apart relatively rapidly, and today are separated by almost exactly 1". Here's a nice report on its orbit. My image is a combination of the best of several exposures I tried with my 5mm eyepiece. I don't usually use this eyepiece because I can't mount the camera to it very securely, nor at the truly appropriate distance, and because of the very limited field of view. But occasionally, I've noticed that the 5mm eyepiece can provide nice views. Here it shows. In the mouseover image, taken with the 12.5mm eyepiece, the binary is only barely resolved.
(8x1/45sec [2x1/90sec mouseover] exposures, 4x zoom, 5mm [12.5mm mouseover] eyepiece, 6" scope; 2008/4/18)

The γ Leo image is a modest improvement on my older image. These 2.0 and 3.6 magnitude stars are separated by 4.6" (3x1/20sec ISO 400 exposures, 4x zoom, 5mm eyepiece, 6" scope; 2008/5/11)

Diffraction

A set of 16 sec exposures to test focus, tracking diffraction, and color.
Sirius: A1 V, m_V = -1.47, B-V = 0.01
Rigel: B8 Iab, m_V = 0.12, B-V = -0.03
Betelgeuse: M2 Iab, m_V = 0.58, B-V = 1.77
24mm eyepiece, 4x zoom. Focus seems OK. Diffraction spikes are doubled, and one pair is diverging. Hadn't notice that before. Perhaps it is an alignment problem. Perhaps related to the 12°F temperature. Sirius is bright enough to cause a faint 3x3 grid of electronic ghosts in addition to the bright optical ghost (visible for each star). (2008/01/20)

α β γ

α PsA = Fomalhaut. 1.16 mag, A3 V, 25.1 ly distant. (2x32sec ISO 400 at 1x zoom)
β And = Mirach. 2.06 mag, M0 III, 199 ly distant. (1x32sec ISO 400 at 4x zoom)
γ And = Almach. 2.26 + 4.84 mag, K3 IIb + B8 V, 355 ly distant. (4x1/60sec ISO 400 at 4x zoom)

Old Telescope, New Mount (Take 2)

Altair

μ Cep

More results from my old f/6 6" reflector on a new Meade LXD75 mount. ([Altair, μ Cep] = [1,1] x [32,64]sec; 6" scope, ISO 400, 25mm eyepiece; 2007/09/15+16)

Nova Scorpii 2007

Nova Scorpii 2007 is indicated in this composite of 3 24-sec ISO 400 images. I'm pleased to have gotten this picture despite various and sundry difficulties. The most serious of which is the light pollution, which prevented me from seeing the nova with my naked eye even though it was an easy target in binoculars. The "mouseover" comparison image was taken under much better conditions in Colorado, 6 months before the nova exploded. (It's an alternate version of the Sco-Sgr image further down on this page.)

The nova's light curve shown below is from the AAVSO. I've added annotations for calendar dates, and a red arrow indicating the date at which my picture was taken.

Infrared

	Visible                     IR
Vega Arcturus

On the left are 1/15 sec visible light images the hot white star Vega, and the cool orange star Arcturus. Both the stars appear to be the same brightness to the naked eye. At infrared wavelengths (redder than red), Arcturus is distinctly brighter as shown in the 2 sec images on the right, taken with an IR filter. The eye cannot see light at these wavelengths, but some digital cameras can, though with low sensitivity. Mouseover the visible spectrum below to see the same view through an IR filter.

Multiple Stars in Virgo and Bootes and Libra

Multiple Multiples and Neighbors

A wide view of Mizar (A+B mag. = 2.27+4.95) and Alcor (mag. = 4.0) and several fainter stars nearby. Each of the stars Mizar A and B is actually a binary, making four stars in all. Alcor might possibly be a very distant companion, but even if not, it is still another member of the Ursa major moving group - a widely dispersed star cluster sharing a common proper motion across the sky. This is a stack of 7x6-sec exposures + 1 12-sec exposure. 2006/04/09.

This image shows the close binary Castor A and B, with their faint red companion Castor C (and another more distant star). Each of the stars Castor A, B and C is actually a binary system. Castor C (also known as YY Gem) happens to be an eclipsing binary -- one of the few such systems composed of M type stars. This is a single 0.1sec 4x zoom exposure, scaled and superimposed on a single 4sec 1x zoom exposure, both at ISO 400.

This second image is taken with the 6" telescope and 12.5 mm eyepiece. It's a combination of 5 1/45th sec ISO 100 exposures. These were the best of about 20 exposures. Most of the rejects were really bad due to the seeing. Castor A and B are only about 4.5" apart, but slowly moving apart. (2007/11/30)

Multiple Stars in Lynx

Along the Southern Milky Way...

Several More Stars

Both Rigel (but not its companion) and σ Orionis appear below, but these new images are better. R Leporis is the deep red star at the left side of the image. (2005/12/20-23)

Yes, More Double Stars

(2005/11/12)

Three Doubles and a Triple (and Another Double)

I stumbled across Enif by accident, as I was using it for a focus check. It's merely a visual double, and not a true binary system. (Enif: 2005/9/11, others: 2005/10/01; 1 Ari: 2005/10/30)

* * * * *

The brightest star to the west (right) of Altair is 190" distant and 9.7 mag.
There seems to be a color difference between the stars of ζ Aqr, but I suspect that's largely a result of atmospheric refraction.
In the linked, deep image of μ Cep, there are at least two equally red (but much fainter) stars. The brightest of these fainter red stars is 324" from μ Cep (to the NW) and 10.6 mag.
(2005/09/08)

Duplicity

Sh 225 and Sh 226 are separated by only 7' and fit easily in a single field of view. They're shown on a rather different scale than the other stars.
χ Cyg is only duplicitous metaphorically. It's a long period variable star which can vary between 3.5 and 14 (!) magnitude. Here, it's at 6th mag. and fading after having peaked at 5th mag. about two months earlier. At minimum it will be several magnitudes fainter than any stars visible in the linked, wider field of view!

α¹ Cap (AB sep. = 45"; 4.6 + 9.2 mag.; 7x2.0sec images; 2.7x zoom; 25 mm eyepiece)
α² Cap (AB sep. = 154"; 3.5 + 9.5 mag.)
α¹ and α² are separated by 378".

Summer Stars

ε Lyr

α Sco   ξ Sco   ο¹ Cyg

α Her   95 Her   70 Oph

ε Lyr (sep. = 208" 1.7" 2.3"; (4.7+6.0)+(4.6+5.3) mag.; 9x0.03sec images; 4x zoom, 12.5mm eyepiece + 6" scope),
α Sco (Antares; 1.0 mag.; 5x0.25sec images; 4x zoom, 25mm eyepiece),
α Her (AB sep. = 5"; 2.2 + 5.3 mag.; 2x0.1sec images; 4x zoom, 12.5mm eyepiece)
ξ Sco (AB sep. = 7.4"; 4.2 + 7.2 mag.; 10x1sec images; 4x zoom, 12.5mm eyepiece),
95 Her (AB sep. = 6.3"; 4.3 + 5.1 mag.; 5x0.25sec images; 4x zoom, 25mm eyepiece)
ο¹ Cyg (AB sep. = 336" AC sep. = 106"; 3.8 + 4.8 + 7.0 mag.; 5x0.25sec images; 1x zoom, 25mm eyepiece),
70 Oph (AB sep. = 4.1"; 4.1 + 6.2 mag.; 5x0.25sec images; 4x zoom, 25mm eyepiece),
These were shot via afocal projection on my Meade ETX-105.
(2005/06/24; 2008/08/14 for ε Lyr).

Alphas and Betas

From left to right:
α Lyr (Vega; AB sep. = 70"; 0.0 + 10 mag.; 0.25+0.5+1+2+4+8+16+32sec images; 1x zoom),
β Lyr (AB sep. = 45"; 3.4 + 6.7 mag.; 4x1sec images; 2.2x zoom),
β Cyg (AB sep. = 34"; 3.0 + 5.1 mag.; 6x1sec images; 4x zoom),
β Sco (AB sep. = 13"; 2.5 + 4.9 mag.; 4x2sec images; 4x zoom),
α Her (AB sep. = 5"; 2.2 + 5.3 mag.; 4x0.25sec images; 4x zoom)
The Vega image is a strange combination, but with a gamma=2.00 stretch, this seems to work pretty well for showing a wide range of brightness. Vega's companion (to the south) is merely another more distant star along the same line of sight. The linked image shows a wider field of view.
The image linked to the Albireo (β Cyg) picture is a single 8sec image at 2x zoom (25mm eyepiece 6-inch scope), which shows many other fainter stars in a wider field. (updated: 2007/09/16)
Except for that picture, these were shot via afocal projection on my Meade ETX-105 with a 25 mm eyepiece.
(2005/05/28, β Sco 2007/06/17).

Stars in Bootes (and Nearby Constellations)

From left to right:
Arcturus (α Boo; -0.07 mag.; 1x1/60sec image; 4x zoom),
ε Boo (AB sep. = 2.4"; 2.3 + 4.8 mag.; 6x0.1sec images; 4x zoom),
μ Boo (AB sep. = 108", BC sep. = 2.2"; 4.3 + 6.5 + 7.6 mag.; 12x0.25sec images; 4x zoom),
ζ CrB (AB sep. = 6.3"; 4.6 + 5.9 mag.; 9x0.25sec images; 4x zoom),
R CrB (5.9var mag.; 7x4sec images; 4x zoom),
Spica (α Vir; 0.96 mag.; 1x0.5sec images; 4x zoom),
ν Dra (AB sep. = 61"; 4.8 + 4.9 mag.; 7x0.5sec images; 4x zoom),
These were shot via afocal projection on my Meade ETX-105 with a 12.5mm (first two) and 25 mm (last five) eyepieces. There's another lower-magnification longer-exposure image of Arcturus below, but I include this one because it clearly shows the first diffraction ring of the telescope's point spread function. The asymmetry of the ring is probably due to a slight misalignment of the camera. The BC pair in the μ Boo image can be seen more clearly in the linked larger picture. (2005/04/25, 2005/04/27, 2005/05/04, 2005/05/08).

1 Star, 2 Stars, Red Star, Blue Star

From left to right:
Arcturus (α Boo; -0.07 mag.; 5x0.25sec images; 4x zoom),
δ Crv (AB sep. = 23"; 2.9 + 9.4 mag.; 6x1sec images; 4x zoom),
Y CVn (5.4 mag.; 4x1sec images; 4x zoom),
α Leo (AB sep. = 180"; 1.3 + 8.1 mag.; 5x0.5sec image; 4x zoom),
Y CVn can also be found in the Ursa Major and Coma Berenices pictures below. These were shot via afocal projection on my Meade ETX-105 with a 25mm eyepiece (2005/04/10 and 2005/04/16).

More Double Stars

From left to right:
ζ Cnc (AB sep. = 0.8", AC sep. = 6.0"; 5.6 + 6.0 + 6.2 mag.; 3x1sec images; 4x zoom),
ι Cnc (AB sep. = 30.5"; 4.2 + 6.6 mag.; 1x3sec image; 1x zoom),
54 Leo (AB sep. = 6.5"; 4.5 + 6.5 mag.; 11x0.5sec images; 4x zoom),
ξ UMa (AB sep. = 1.8"; 4.3 + 4.8 mag.; 1x0.25sec image; 4x zoom),
α CVn (AB sep. = 20"; 2.8 + 5.6 mag.; 4x0.125sec image; 4x zoom),
The very close AB pair of ζ Cnc cannot be resolved here. These were shot via afocal projection on my Meade ETX-105 with a 12.5mm eyepiece (2005/04/05), except for Cor Caroli (α CVn) and ι Cnc which were with my 6" reflector and 25mm eyepiece.

Various Stars

From left to right:
Rigel (β Ori: 0.15 mag.; 5x0.1sec images),
Sirius (α CMa: -1.46 mag.; 5x0.1sec images),
Betelgeuse (α Ori: 0.43 mag.; 3x0.1 sec images),
β Mon (AB sep. = 7.2", BC sep. = 2.9"; 3.75 + 5.00 + 5.31 mag.; 4x0.5sec images),
σ Ori (AC sep. = 11.2", AD sep. = 12.9", AE sep. = 42"; 3.75 + 10 + 6.78 + 6.34 mag.; 4x2.0sec images),
Polaris (α UMi: AB sep. = 18", 2.0v + 8.2 mag.; 4x4sec images).
The AB pair of stars in σ Ori are separated by only 0.25" and cannot be seen here, and the faint C component can only be seen in a greatly stretched version of the picture. The stretched version also shows the faint wide triple system Σ761. The wider field picture of Sirius is a single 3-sec exposure which also captures three nearby 8th magnitude stars. These were shot via afocal projection on my Meade ETX-105 with a 12.5mm eyepiece and the camera's 4x zoom. 2005/03/05 (except 2005/03/14 for Sirius, and 2005/3/30 and a 25 mm eyepiece for Polaris).

Binary Stars

From left to right: Castor (α Gem: 4.4" sep. 1.6 + 3.0 mag.), Algieba (γ Leo: 4.6" sep. 2.0 + 3.6 mag.), and Mizar (ζ UMa: 14" sep. 2.2 + 3.8 mag.). Each of the visible stars in Castor and Mizar is an unresolved binary system, with orbital periods of 3 - 180 days. The images are stacks of 6, 3, and 5 1/15-sec frames, with a contrast adjustment, cropped, and rescaled at 25%. They were shot via afocal projection on my Meade ETX-105 with a 25mm eyepiece and the camera's 4x zoom + 2x telephoto lens. 2005/02/12.
Click on the Mizar image to see a wider view of Mizar and Alcor (mag.=4.0) and several fainter stars nearby. This one is a stack of 7x6-sec exposures + 1 12-sec exposure. 2006/04/09.

First Magnitude Stars

The red giant Aldebaran (α Tau) and the almost resolved binary star Castor (α Gem). This is mostly a test of image sharpness and color for my afocal setup.

Theta Tau

Theta-1 and theta-2 Tau: a pair of stars forming a naked eye double star in the Hyades. The expanded view shows a couple of fainter stars and real variations in color.

γ And

The contrasting double star γ Andromeda (Almach). The stars are 2nd and 5th magnitude and are separated by 10". The brighter star is a K2 or K3 II bright giant. The fainter star is actually a triple star system (of late B or early A stars). This is an average of two 1-second exposures through a 6" telescope.

Mizar A+B from Video

This image is created from a stack of a few dozen video frames collected with a Meade Electronic Eyepiece attached to a Meade ETX-105. The original recording was to video tape and then much later converted to digital video. Slight to moderate contrast adjustments were applied after the stacking.

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Rick Arendt
December 6, 2009