Bakersfield College

April 5, 2014 brief

Bakersfield Night Sky – April 5, 2014
By Nick Strobel

Astronomy Day is next Saturday. This free event sponsored by Kern Astronomical Society will take place on April 12th at the new Houchin Community Blood Bank at 11515 Bolthouse Drive (off of Buena Vista Rd between White Lane and Panama Lane). On Monday there will be a Solar Social from 4 to 7 PM with pizza and snacks and observing the Sun with the KAS solar telescopes to kick off Astronomy Week in the buildup to the full day of astronomy workshops and speakers, including Alex Filippenko and Terry Himes on Saturday. More information about Astronomy Day and fliers for downloading are posted on the Astronomy Day site at kernastro.org/astroday .

The following week in the very early hours of April 15th we will get to experience a total lunar eclipse. (No, this has nothing to do with it being tax day.) A total lunar eclipse happens when the Full Moon goes through the Earth's umbra shadow. The umbra shadow is the region in which the light source would be totally blocked, so it is the darkest part of a shadow. For this eclipse the Moon will go through the southern part of the Earth's umbra. The inset of the attached star chart shows the particulars of this eclipse.  The umbral part of the eclipse begins at 10:58 PM our time on April 14th and totality goes from 12:07 AM to 1:24 AM on April 15th. The Moon will leave the umbra at 2:33 AM. Although the Moon will be in the darkest part of the Earth's shadow, the Moon will have a reddish color as sunlight bends through the Earth's atmosphere to reach the Moon and the bluer colors in the sunlight are scattered away. I have diagrams describing lunar eclipses and photos of eclipses in my online astronomy book at www.astronomynotes.com/nakedeye/s14.htm .

One event we seemed to have detected directly for the first time is the super-rapid accelerated expansion of the universe in the first 10-36 second after the Big Bang. That's a trillionth of trillionth of a trillionth of a second! This super-rapid expansion is called "cosmological inflation" or just "inflation" if the context is clear that you're talking about cosmology and not about economics. Inflation was an idea invented by Alan Guth in 1981 and further developed by Andrei Linde and others in the following years. Inflation was invented to explain shortcomings in the original Big Bang theory. In an earlier draft of this column I explained what those problems were but it took several paragraphs to do that. For those who want to "geek out" I posted the original draft in the Night Sky section of the William M Thomas Planetarium's website at www.bakersfieldcollege.edu/planetarium and even more details are available in the cosmology chapter of my online Astronomy Notes book at www.astronomynotes.com/cosmolgy/s12.htm .

Further development of the inflation concept also explained other features of the universe including the large-scale structure of the universe made of the distribution of galaxy clusters into long strings of superclusters and the overall spatial curvature of the universe that determines how it will expand in the future. Unfortunately for inflation, there were other ways to explain those things too, so astronomers and physicists were looking for a stronger proof or disproof of inflation. Note that disproving a scientific model or theory can be just as valuable because at least we know we don't have to spend mental energy exploring the blind alley of the discounted model.

Strong evidence for inflation would be a particular signature of gravitational waves in the cosmic microwave background because that signature would be unique to inflation. The cosmic microwave background is leftover radiation from the early history of the universe when the universe had cooled sufficiently enough for protons and electrons (and neutrons) to get together to form atoms for the first time. Although that radiation is coming from about 380,000 after the Big Bang, information about what was happening in the universe before then (even from the time of the first 10-36second) is recorded in that microwave background if we're clever enough to tease out that information. What was happening in the first fraction of a second affected what the universe was doing thousands of years later.

Because gravitational waves from the time of inflation are unique to inflation, we're looking to see if we can detect those gravitational waves in the cosmic microwave background. Scientists working on the Background Imaging of Cosmic Extragalactic Polarization 2 (BICEP2) experiment at the South Pole might have spotted that signature of the gravitational waves. Their observations need to be confirmed by other research teams before we can be sure the BICEP2 team didn't make a mistake. Peer review is a critical part of the scientific process to make sure we don't fool ourselves with our pre-conceived ideas.

One other exciting piece of astronomy news has been about a small scattered disk object discovered in 2012 called 2012 VP113. The "scattered disk" is a sort of transition zone between the Kuiper Belt where Pluto resides and the very distance and large Oort Cloud of comets. Other scattered disk objects include Eris, Sedna, and Comet Hale Bopp. What is causing the buzz about VP113 is the determination that the closest approach of its orbit, the perihelion, is aligned like that of Sedna and some other far-flung objects. The similarity of that part of their orbits has led some astronomers to speculate about the existence of a large planet as big as the Earth or larger "super-Earth" orbiting about 250 AU from the Sun (that's about six times farther than Pluto's orbit). A large planet like that could have nudged these smaller scattered disk objects into similar sort of orbits. Well, speculation of a big planet like that is sure to capture the attention of the mainline media as well as purveyors of doomsday predictions and NASA cover-ups.

A super-Earth that far out from the Sun would not be detectable with current infrared telescopes. Something like the upcoming James Webb Space Telescope might be able to image it if we knew right where to look. I'm a bit skeptical about the existence of this super-Earth. The authors of the paper describing the orbit of VP113 also note that the super-Earth is just at the "suggestive stage." A lot more observations need to be done to strengthen the case for this proposed object beyond the mere speculative, suggestive status it currently has.

In tonight's night sky, Jupiter will be high up in the south just after sunset between the two string of stars that make up the Gemini twins. Brighter than any star in our night sky, Jupiter will be the first star-like object you see after sunset. It is bright enough that you'll still be able to see it easily even with the fat Waxing Crescent Moon nearby at the feet of the Gemini twin, Castor. The attached star chart shows the sky at 9 PM and where the Moon will be between tonight and the night of the Full Moon for the eclipse. The Moon will be at First Quarter phase tomorrow. On Tuesday, April 8th, the Waxing Gibbous Moon will be below the Beehive Cluster in Cancer. April 10th the gibbous Moon will be below Regulus at the bottom of the Sickle part of Leo. On April 13th, the bright gibbous Moon will be next to orange-red Mars in the middle of Virgo. Mars is visible by 8 PM and should be bright enough to see even when the Moon is close to it on the 13th. Jupiter, Mars, and the Moon will be targets to observe with the KAS telescopes on Astronomy Day. On the night of the total lunar eclipse, April 14th, the Full Moon will be just above the bright star Spica on the eastern side of Virgo. April 14th is also when we will be closest to Mars as we move past it in our faster, inner orbit.

Saturn becomes visible at around 10:30 PM tonight and by the night of the eclipse, it should be visible shortly after 10 PM. Your distance from the mountains in the east will determine when you first see it rising in the east with the stars of Libra. In the pre-dawn morning, you'll see bright Venus low in the east an hour before sunrise. The Waning Crescent Moon will be next to Venus the mornings of April 25th and 26th.

Want to see more of the stars at night and save energy? Shield your lights so that the light only goes down toward the ground. See www.darksky.orgfor how.

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Nick Strobel
Director of the William M Thomas Planetarium at Bakersfield College
Author of the award-winning website www.astronomynotes.com

Early April 2014 looking southeast at 9 PM

Kern Community College District