Chap 16: Galaxies
... Q: The first question of our mid-term exam tells us that the farthest star can be seen by naked eyes should be 5167 light years away. Why are we able to see Andromeda galaxy (M31) which is about 2.54 million light years away without aid when the night sky is clear? A: Surely we can’t see a star whic ...
... Q: The first question of our mid-term exam tells us that the farthest star can be seen by naked eyes should be 5167 light years away. Why are we able to see Andromeda galaxy (M31) which is about 2.54 million light years away without aid when the night sky is clear? A: Surely we can’t see a star whic ...
Astronomy 16: Introduction
... • Grouped into "clouds" – ill-defined variety of structures • M ~ 1 – 106 M; GMCs have M > 104 M • size ~ 1-100 pc ; T ~ 10 K ; nH ~ 102 – 106 cm-3 • Opaque! E.g. nH = 104 cm-3 and L ~ 1 pc. What is AV ? • 1% of ISM volume (f = 0.01), 50% of ISM mass! • Almost entirely molecular hydrogen (H2), but ...
... • Grouped into "clouds" – ill-defined variety of structures • M ~ 1 – 106 M; GMCs have M > 104 M • size ~ 1-100 pc ; T ~ 10 K ; nH ~ 102 – 106 cm-3 • Opaque! E.g. nH = 104 cm-3 and L ~ 1 pc. What is AV ? • 1% of ISM volume (f = 0.01), 50% of ISM mass! • Almost entirely molecular hydrogen (H2), but ...
The chemical enrichment of the ICM from hydrodynamical simulations
... In the above equation, φ (m) is the IMF, mB is the total mass of the binary system, m2 is the mass of the secondary companion, τm is the mass–dependent life–time and ψ (t) is the star formation rate. The variable µ = m2 /mB is distributed according to the function f (µ ), while A is the fraction of ...
... In the above equation, φ (m) is the IMF, mB is the total mass of the binary system, m2 is the mass of the secondary companion, τm is the mass–dependent life–time and ψ (t) is the star formation rate. The variable µ = m2 /mB is distributed according to the function f (µ ), while A is the fraction of ...
A Practical Guide to Exoplanet Observing
... Note: here the term Science Images refers to the raw images of the field-of-view containing the exoplanet host star; such images are also often referred to as Lights by other image processing software. The AIJ Analysis subdirectory is where measurement and model fit files from AIJ can be stored. If ...
... Note: here the term Science Images refers to the raw images of the field-of-view containing the exoplanet host star; such images are also often referred to as Lights by other image processing software. The AIJ Analysis subdirectory is where measurement and model fit files from AIJ can be stored. If ...
Astronomical Picture of the Day
... The Orion Nebula (a) is a giant cloud of gas and dust in which new stars and planets are forming. It is located about 1,500 light-years from Earth, which means the light recorded in the photograph took about 1,500 years to reach us. Thus, we see it as it was about 1,500 years ago. Photograph (b) sho ...
... The Orion Nebula (a) is a giant cloud of gas and dust in which new stars and planets are forming. It is located about 1,500 light-years from Earth, which means the light recorded in the photograph took about 1,500 years to reach us. Thus, we see it as it was about 1,500 years ago. Photograph (b) sho ...
OBSERVING LUNAR AND ASTEROIDAL OCCULTATIONS: A
... Without having a record of accurate time, your observations are relatively useless for scientific contribution. If you are calling out your times into a voice recorder while watching through the telescope, your reaction time (difference between the moment you saw the event and when you called it out ...
... Without having a record of accurate time, your observations are relatively useless for scientific contribution. If you are calling out your times into a voice recorder while watching through the telescope, your reaction time (difference between the moment you saw the event and when you called it out ...
ASTRONOMICAL BINOCULARS
... years, so they may be seen edge-on (like a thin line) or broadside (like giant “ears” on each side of the planet). You will need a good steady atmosphere to achieve a worthwhile view of Saturn. If you look closely enough, you can see the Cassini division - a thin, dark gap in the rings. You can also ...
... years, so they may be seen edge-on (like a thin line) or broadside (like giant “ears” on each side of the planet). You will need a good steady atmosphere to achieve a worthwhile view of Saturn. If you look closely enough, you can see the Cassini division - a thin, dark gap in the rings. You can also ...
Chemical analysis of 24 dusty (pre-) main
... Herbig Ae/Be (HAEBE) stars are generally thought to be the somewhat more massive analogues of the T Tauri stars, which are low-mass pre-main-sequence stars. They were first defined as a class in 1960 by Herbig, based on three observational criteria: the stars have spectral type A or earlier, display ...
... Herbig Ae/Be (HAEBE) stars are generally thought to be the somewhat more massive analogues of the T Tauri stars, which are low-mass pre-main-sequence stars. They were first defined as a class in 1960 by Herbig, based on three observational criteria: the stars have spectral type A or earlier, display ...
2Discovering the Universe for Yourself
... interstellar clouds that make up the Milky Way in the night sky; that is why the band of light makes a full The Milky Way in the night sky is our view circle around our sky. The Milky in all directions into the disk of our galaxy. Way appears somewhat wider in the direction of the constellation Sagi ...
... interstellar clouds that make up the Milky Way in the night sky; that is why the band of light makes a full The Milky Way in the night sky is our view circle around our sky. The Milky in all directions into the disk of our galaxy. Way appears somewhat wider in the direction of the constellation Sagi ...
Gaia talk
... Subject: GAIA is not an asteroid Hi Gerry, Simon Just thought you might find it amusing that Gaia was listed a Near-Earth asteroid for 14 hours today until we realised what it was :-) It was found 4 days ago by Pan-STARRS and it had a short life as confirmed asteroid 2015 HP116. (For some reason the ...
... Subject: GAIA is not an asteroid Hi Gerry, Simon Just thought you might find it amusing that Gaia was listed a Near-Earth asteroid for 14 hours today until we realised what it was :-) It was found 4 days ago by Pan-STARRS and it had a short life as confirmed asteroid 2015 HP116. (For some reason the ...
Chapter 15 THE MILKY WAY IN RELATION TO OTHER GALAXIES
... Hodge’s value for hHII for the Galaxy is 2.35±0.05 kpc, which would be consistent with the Galaxy also being of type Sb. However, using other data hHII can also be estimated as 4.6±1.0 kpc (van der Kruit, 1987). Color is known to correlate with Hubble type, as discussed above. For the Galaxy we unfo ...
... Hodge’s value for hHII for the Galaxy is 2.35±0.05 kpc, which would be consistent with the Galaxy also being of type Sb. However, using other data hHII can also be estimated as 4.6±1.0 kpc (van der Kruit, 1987). Color is known to correlate with Hubble type, as discussed above. For the Galaxy we unfo ...
Rocky planetesimals as the origin of metals in DZ stars
... where hydrogen is detected or inferred (Dufour et al. 2007) versus height above the Galactic mid-plane and tangential speed. No obvious pattern is seen, although there may be a higher density of DZA stars near the Galactic disc and perhaps also towards more modest speeds, but the former may be an ob ...
... where hydrogen is detected or inferred (Dufour et al. 2007) versus height above the Galactic mid-plane and tangential speed. No obvious pattern is seen, although there may be a higher density of DZA stars near the Galactic disc and perhaps also towards more modest speeds, but the former may be an ob ...
THE HELIACAL RISE OF SIRIUS- Algorithm
... The atmospheric extinction for a given place shows how many star-magnitudes are extinguished by one earth atmosphere. In the best case, in a dry mountain desert, the extinction will be around 0.10. In the worse case, around some sea coasts, it may reach 0.40 and even 0.50. There are some scholars wh ...
... The atmospheric extinction for a given place shows how many star-magnitudes are extinguished by one earth atmosphere. In the best case, in a dry mountain desert, the extinction will be around 0.10. In the worse case, around some sea coasts, it may reach 0.40 and even 0.50. There are some scholars wh ...
Preview Sample 3
... A) They are the stars close to the north celestial pole. B) They always remain above your horizon. C) They make relatively small circles, traveling clockwise around the north celestial pole. D) Like all other stars, they rise in the east and set in the west. E) You cannot see them from the Southern ...
... A) They are the stars close to the north celestial pole. B) They always remain above your horizon. C) They make relatively small circles, traveling clockwise around the north celestial pole. D) Like all other stars, they rise in the east and set in the west. E) You cannot see them from the Southern ...
- StealthSkater
... planets. Apparently the formation of a planetary system robs the star of much of its rotational momentum. For two reasons, then, we eliminate stars of class 'F4' and above: (1) most of them rotate rapidly and thus seem to be planet-less; and (2) their stable lifespans are too brief for advanced life ...
... planets. Apparently the formation of a planetary system robs the star of much of its rotational momentum. For two reasons, then, we eliminate stars of class 'F4' and above: (1) most of them rotate rapidly and thus seem to be planet-less; and (2) their stable lifespans are too brief for advanced life ...
WGCP 5th Jan 16 Astrophotography by Steve Baldwin
... http://www.startrails.de/html/software.html This is simple to use and allows you to load your images and dark frames. Star trails can also be created within Photoshop but I have always used this specific star trails application. There are others available. One downside of the software is that it ...
... http://www.startrails.de/html/software.html This is simple to use and allows you to load your images and dark frames. Star trails can also be created within Photoshop but I have always used this specific star trails application. There are others available. One downside of the software is that it ...
Astrophysics Pristine CNO abundances from Magellanic Cloud B stars
... Large Magellanic Cloud (LMC). Apart from H ii regions, unevolved OB-type stars are currently the only accessible source of present-day CNO abundances for the MCs not altered by stellar evolution. Using UVES on the VLT, we obtained spectra of sufficient resolution (R = 20 000) and signal-to-noise (S/ ...
... Large Magellanic Cloud (LMC). Apart from H ii regions, unevolved OB-type stars are currently the only accessible source of present-day CNO abundances for the MCs not altered by stellar evolution. Using UVES on the VLT, we obtained spectra of sufficient resolution (R = 20 000) and signal-to-noise (S/ ...
Planetary Nebula
... located about 1,500 light-years away in Gemini. It was originally discovered in 1955 by UCLA astronomer George O. Abell, who classified it as an old planetary nebula. The braided serpentine filaments of glowing gas suggests the serpent hair of Medusa found in ancient Greek mythology. ...
... located about 1,500 light-years away in Gemini. It was originally discovered in 1955 by UCLA astronomer George O. Abell, who classified it as an old planetary nebula. The braided serpentine filaments of glowing gas suggests the serpent hair of Medusa found in ancient Greek mythology. ...
Ursa Minor
Ursa Minor (Latin: ""Smaller She-Bear"", contrasting with Ursa Major), also known as the Little Bear, is a constellation in the northern sky. Like the Great Bear, the tail of the Little Bear may also be seen as the handle of a ladle, hence the name Little Dipper. It was one of the 48 constellations listed by the 2nd-century astronomer Ptolemy, and remains one of the 88 modern constellations. Ursa Minor has traditionally been important for navigation, particularly by mariners, due to Polaris being the North Star.Polaris, the brightest star in the constellation, is a yellow-white supergiant and the brightest Cepheid variable star in the night sky, ranging from apparent magnitude 1.97 to 2.00. Beta Ursae Minoris, also known as Kochab, is an aging star that has swollen and cooled to become an orange giant with an apparent magnitude of 2.08, only slightly fainter than Polaris. Kochab and magnitude 3 Gamma Ursae Minoris have been called the ""guardians of the pole star"". Planets have been detected orbiting four of the stars, including Kochab. The constellation also contains an isolated neutron star—Calvera—and H1504+65, the hottest white dwarf yet discovered with a surface temperature of 200,000 K.