The HR Diagram Interpreted (PowerPoint version)
... You may say “so what?” – perhaps you expected there to be very small stars. But further analysis reveals something amazing. ...
... You may say “so what?” – perhaps you expected there to be very small stars. But further analysis reveals something amazing. ...
Orion
... by long exposure photos (see e.g. Burnham) and contains, besides the Orion nebula near its center, the following objects, often famous on their own: Barnard's Loop, the Horsehead Nebula region, and the reflection nebulae around M78. The gaseous nature of the Orion Nebula was revealed in 1865 with th ...
... by long exposure photos (see e.g. Burnham) and contains, besides the Orion nebula near its center, the following objects, often famous on their own: Barnard's Loop, the Horsehead Nebula region, and the reflection nebulae around M78. The gaseous nature of the Orion Nebula was revealed in 1865 with th ...
solutions - Las Cumbres Observatory
... he larger star uses more of its fuel and its mass goes down visibly on the graph. The 1 solar mass star appears to lose very little ...
... he larger star uses more of its fuel and its mass goes down visibly on the graph. The 1 solar mass star appears to lose very little ...
Finding Constellations From Orion
... Following the stars of Orion’s Belt backwards (from 3 to 1) points us to Sirius (SEER-e-us), the Dog Star. This is the brightest star in the sky, and is part of the constellation Canis Major, the Great Dog. Drawing a line from Bellatrix (bell-LAY-triks) through Betelgeuse points us to Procyon (PRO- ...
... Following the stars of Orion’s Belt backwards (from 3 to 1) points us to Sirius (SEER-e-us), the Dog Star. This is the brightest star in the sky, and is part of the constellation Canis Major, the Great Dog. Drawing a line from Bellatrix (bell-LAY-triks) through Betelgeuse points us to Procyon (PRO- ...
Star and Sun Properties
... • As stars age and pass through different stages, their positions on the H-R diagram change. ...
... • As stars age and pass through different stages, their positions on the H-R diagram change. ...
Light as a Wave (1) Distances to Stars
... We already know: flux increases with surface temperature (~ T4); hotter stars are brighter. ...
... We already know: flux increases with surface temperature (~ T4); hotter stars are brighter. ...
ASTR100 Homework #5 Solutions Chapter 11 #29, 31 Due
... Decide whether the statement makes sense or does not. Explain clearly. If you could look inside the Sun today, you’d find that its core contains a much higher proportion of helium and a lower proportion of hydrogen than it did when the Sun was born. This statement makes sense because over the last 4 ...
... Decide whether the statement makes sense or does not. Explain clearly. If you could look inside the Sun today, you’d find that its core contains a much higher proportion of helium and a lower proportion of hydrogen than it did when the Sun was born. This statement makes sense because over the last 4 ...
this article as a PDF
... confused earlier observers whose incorrect naming convention has stayed with us to this day. ...
... confused earlier observers whose incorrect naming convention has stayed with us to this day. ...
Main Sequence Star
... a) Size of giants depends on the initial mass b) Could be a super red giant like Betelgeuse ...
... a) Size of giants depends on the initial mass b) Could be a super red giant like Betelgeuse ...
Another exAmple: expository mode
... known as nuclear fusion to produce light. As stars use up this hydrogen, in a process that takes billions of years, they pass through certain phases or stages. In each stage, the star’s brightness, temperature, and size change. The redgiant phase occurs when the star begins to run out of hydrogen. I ...
... known as nuclear fusion to produce light. As stars use up this hydrogen, in a process that takes billions of years, they pass through certain phases or stages. In each stage, the star’s brightness, temperature, and size change. The redgiant phase occurs when the star begins to run out of hydrogen. I ...
Betelgeuse
Betelgeuse (/ˈbiːtəldʒuːz/, /ˈbɛtəldʒuːz/, /ˈbiːtəldʒɜrz/ or /ˈbiːtəldʒuːs/), also known by its Bayer designation Alpha Orionis (shortened to α Orionis or α Ori), is the ninth-brightest star in the night sky and second-brightest in the constellation of Orion. Distinctly reddish, it is a semiregular variable star whose apparent magnitude varies between 0.2 and 1.2, the widest range of any first-magnitude star. Betelgeuse is one of three stars that make up the Winter Triangle, and it marks the center of the Winter Hexagon. The star's name is derived from the Arabic إبط الجوزاء Ibt al-Jauzā', meaning ""the hand of Orion"". The Arabic letter for Y (which has two dots) was misread as B (with one dot) by medieval translators, creating the initial B in Betelgeuse.The star is classified as a red supergiant of spectral type M2Iab and is one of the largest and most luminous observable stars. If Betelgeuse were at the center of the Solar System, its surface would extend past the asteroid belt, possibly to the orbit of Jupiter and beyond, wholly engulfing Mercury, Venus, Earth and Mars. Estimates of its mass are poorly constrained, but range from 5 to 30 times that of the Sun. Its distance from Earth was estimated in 2008 at 640 light-years, yielding a mean absolute magnitude of about −6.02. Less than 10 million years old, Betelgeuse has evolved rapidly because of its high mass. Having been ejected from its birthplace in the Orion OB1 Association—which includes the stars in Orion's Belt—this crimson runaway has been observed moving through the interstellar medium at a supersonic speed of 30 km/s, creating a bow shock over 4 light-years wide. Currently in a late stage of stellar evolution, the supergiant is expected to proceed through its life cycle before exploding as a type II supernova within the next million years. An observation by the Herschel Space Observatory in January 2013 revealed that the star's winds are crashing against the surrounding interstellar medium.In 1920, Betelgeuse became the second star (after the Sun) to have the angular size of its photosphere measured. Since then, researchers have used telescopes with different technical parameters to measure the stellar giant, often with conflicting results. Studies since 1990 have produced an angular diameter (apparent size) ranging from 0.043 to 0.056 arcseconds, an incongruity largely caused by the star's tendency to periodically change shape. Due to limb darkening, variability, and angular diameters that vary with wavelength, many of the star's properties are not yet known with any certainty. Adding to these challenges, the surface of Betelgeuse is obscured by a complex, asymmetric envelope roughly 250 times the size of the star, caused by colossal mass loss.