Shasta Astronomy Club
Newsletter
Astronomers Discover The Oldest Known Star In The Universe
February 10, 2014 | by Lisa Winter
A few hundred thousand years after
the Big Bang, hydrogen gas started
to heat up and the first stars were
formed. One of these first stars, which
formed around 13.7 billion years
ago, has been discovered for the first
time. The discovery was made by lead
researcher Stefan Keller of The Australian National University and the
results were published in Nature.
Dr. Keller’s team is one that operates
the SkyMapper telescope at the Siding Spring Observatory in New South
Wales. Because elements heavier
than helium are forged in the cores of
stars, the first ones were made mostly
out of hydrogen. The telescope is
able to find these first stars because
the low iron content influences their
color. Using this technique to find
early stars, the SkyMapper is currently in a 5-year-long survey, mapping
the ancient Southern sky.
The team made the discovery of a lifetime when they discovered the chemical signature from a 13.7 billion year old star; one
of the first ever. This star formed so early in our Universe’s history, was most likely a second-generation star. Because of the
chemical composition, astronomers can gather information about the earlier primordial star, which is believed to be 60 times
more massive than our sun and composed of hydrogen and helium.
The stars we are most familiar with today have different stages in their life cycle. For massive stars (those which are over nine
solar masses) heavy elements are fused in the core of the star, up until it hits iron. The nuclei are so tightly bound that it actually consumes energy, instead of producing it like other elements. As more and more iron is created, the star’s core becomes so
massive that it eventually collapses, signifying the death of the star. The supernova explosion is violent and all of the elements
are ejected out where they will eventually form new stars or planetary bodies. It had long been assumed that the first stars exploded in similar ways, but the team found that this wasn’t the case. The explosion from the primordial star’s death was relatively low-energy. While the lighter elements were ejected and would go into new
stars, the heavier elements, like the iron, were consumed by the black hole that formed after the supernova. The newly-discovered second-generation star did not have the iron that astronomers believed they would have.
The discovery of this ancient star has given astronomers a deeper insight about the origins of stars and how certain elements
began to spread around the early Universe. These low-energy supernovae were likely very common among the first stars and
future research will determine when they began to gather more energy and become the explosive events we know them to be
today. Star Party Location: Mount Shasta Mine Loop Trailhead Parking Lot.
March 2014
Shasta Astronomy Club
Newsletter
Einstein’s lost theory
uncovered
Physicist explored the idea of a steadystate Universe in 1931.
A manuscript that lay unnoticed by
scientists for decades has revealed
that Albert Einstein once dabbled with
an alternative to what we now know
as the Big Bang theory, proposing
instead that the Universe expanded
steadily and eternally. The recently
uncovered work, written in 1931, is
reminiscent of a theory championed
by British astrophysicist Fred Hoyle
nearly 20 years later. Einstein soon
abandoned the idea, but the manuscript reveals his continued hesitance
to accept that the Universe was created during a single explosive event.
Evidence for the Big Bang first
emerged in the 1920s, when US astronomer Edwin Hubble and others
discovered that distant galaxies are
moving away and that space itself
is expanding. This seemed to imply
that, in the past, the contents of the
observable Universe had been a very
dense and hot ‘primordial broth’.
But, from the late 1940s, Hoyle
argued that space could be expanding eternally and keeping a roughly
constant density. It could do this by
continually adding new matter, with
elementary particles spontaneously
popping up from space, Hoyle said.
Particles would then coalesce to
form galaxies and stars, and these
would appear at just the right rate
to take up the extra room created
by the expansion of space. Hoyle’s
Universe was always infinite, so its
size did not change as it expanded. It
was in a ‘steady state’.
The newly uncovered document
shows that Einstein had described
essentially the same idea much
earlier. “For the density to remain
constant new particles of matter
must be continually formed,” he
writes. The manuscript is thought to
have been produced during a trip to
California in 1931 — in part because
it was written on American note
paper.
t had been stored in plain sight at
the Albert Einstein Archives in Jerusalem — and is freely available to
view on its website — but had been
mistakenly classified as a first draft
of another Einstein paper. Cormac
O’Raifeartaigh, a physicist at the
Waterford Institute of Technology in
Ireland, says that he “almost fell out
of his chair” when he realized what
the manuscript was about. He and
his collaborators have posted their
findings, together with an English
translation of Einstein’s original
German manuscript, on the arXiv
preprint server (C. O’Raifeartaigh
et al. Preprint at http://arxiv.org/
abs/1402.0132; 2014) and have
submitted their paper to the European Physical Journal.
“This finding confirms that Hoyle
was not a crank,” says study co-author Simon Mitton, a science historian at the University of Cambridge,
UK, who wrote the 2005 biography
Fred Hoyle: A Life in Science. The
mere fact that Einstein had toyed
with a steady-state model could
have lent Hoyle more credibility as
he engaged the physics community
in a debate on the subject. “If only
Hoyle had known, he would certainly have used it to punch his opponents,” O’Raifeartaigh says.
Although Hoyle’s model was eventually ruled out by astronomical
observations, it was at least mathematically consistent, tweaking
the equations of Einstein’s general
theory of relativity to provide a possible mechanism for the spontane-
Star Party Location: Mount Shasta Mine Loop Trailhead Parking Lot.
March 2014
Shasta Astronomy Club
Newsletter
ous generation of matter. Einstein’s
unpublished manuscript suggests
that, at first, he believed that such
a mechanism could arise from his
original theory without modification. But then he realized that he
had made a mistake in his calculations, O’Raifeartaigh and his team
suggest. When he corrected it —
crossing out a number with a pen
of a different colour — he probably
decided that the idea would not
work and set it aside.
The manuscript was probably “a
rough draft commenced with excitement over a neat idea and soon
abandoned as the author realized he
was fooling himself”, says cosmologist James Peebles of Princeton University in New Jersey. There seems
to be no record of Einstein ever
mentioning these calculations again.
But the fact that Einstein experimented with the steady-state concept demonstrates his continued
resistance to the idea of a Big Bang,
which he at first found “abominable”, even though other theoreticians had shown it to be a natural
consequence of his general theory of
relativity. (Other leading research-
ers, such as the eminent Cambridge
astronomer Arthur Eddington, were
also suspicious of the Big Bang idea,
because it suggested a mystical
moment of creation.) When astronomers found evidence for cosmic
expansion, Einstein had to abandon
his bias towards a static Universe,
and a steady-state Universe was the
next best thing, O’Raifeartaigh and
his collaborators say.
Helge Kragh, a science historian
at Aarhus University in Denmark,
agrees. “What the manuscript shows
is that although by then he accepted
the expansion of space, [Einstein]
was unhappy with a Universe changing in time,” he says.
Star Parties for The Redding
School of the Arts
Last year the Shasta Astronomy Club
had the pleasure of being invited to
put on a star party at the RSA. We
had about a half dozen club members
turn out and a fantastic turnout from
students and parents who wanted to
explore our Universe. This year, SAC
has been invited back for not one, but
two star parties!
In April the 6th grade class will be
spending a week at the W.E.S. (NEED)
Camp studying science and the natural world. They have asked us to be
part of this educational opportunity
and add the night sky to the student’s environmental education. In
May, we’ll be hosting a school-wide
star party on campus at the Redding
School of the Arts.
The exact dates for these two fantastic
events are still being worked out but
the W.E.S. event will be around April
1-3rd and we’re hoping to get the May
date on a Friday (other than Memorial
Day weekend). Once the dates are
set, there will be an event announcement posted on the club calendar.
Star Party Location: Mount Shasta Mine Loop Trailhead Parking Lot.
March 2014
Shasta Astronomy Club
Newsletter
Found Opportunity
By Phil Plait
It’s actually rather amazing what you
can see from orbit. Once you’re off
the ground, above it, your perspective
changes, and you can put things in
context. Signs of civilization can shrink
down to almost nothing compared
with the glory of nature, making them
difficult to spot.
For example, peruse this image taken
by a satellite:
Can you even see any signs of
human activity there on the surface?
Oh, wait a second. My apologies. I
forgot to mention: That’s not the
surface of Earth … it’s the surface
of Mars. And the signs of humanity you see there are really just a
single sign.
Can you spot that blip right in the
center? That’s the Mars rover Opportunity!
It’s only about
2.3 x 1.6 meters
(7.5 x 5.2 feet) in
size, so it’s just a
few pixels across
as seen by the
HiRISE camera
on the Mars
Reconnaissance
Orbiter. If the
scientists and
engineers programming the
probe didn’t
know exactly
where Opportunity was, it
would be impossible to find!
But we know
exactly where
all our working
hardware is on
Mars, and we
know exactly
where the orbiting cameras
point, making
it far simpler to
get pictures of
the land-bound rovers.
Opportunity is seen here at
what’s called Solander Point,
where it found that odd rock
nicknamed the “jelly doughnut.”
The rock suddenly appeared next
to the rover, when earlier images
taken by Opportunity showed
bare ground. That was quite a
mystery, but it’s now pretty clear
that the rock was a piece of a
larger one broken off by one of
the rover’s wheels. Images like
this one from HiRISE are pretty
useful when things like this
happen; it shows no fresh craters nearby, making it unlikely
the rock was ejected by a small
impact.
But for those of us back home
who don’t study Mars for a living
(and, I’d wager, even for those
who do), images like this are still
a thrill. As my friend Emily Lakdawalla puts it, “Seeing a spacecraft on the surface of a planet
from another spacecraft never
gets old.”
She’s right. It’s a great reminder
that we humans are amazing
when we want to be. We can, in
a short time, go from creating
myths about lights in the sky to
landing on them and discovering
their truths for ourselves.
Star Party Location: Mount Shasta Mine Loop Trailhead Parking Lot.
March 2014
Shasta Astronomy Club
Newsletter
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The Shasta Astronomy Club Newsletter is always looking for articles, photos and suggestions from our readers. If you have a story
to tell about your adventures in amateur astronomy or a quick tip that needs to be shared, go ahead and send it to us at the following
email address –
[email protected]
Articles can be in MS Word, Rich Text, PDF, or Plain Text. We can also cut and paste directly from an email.
Photos can be in JPG, PNG, PSD, GIF or various other graphic formats. Note, due to copyright issues we can only accept original
photos.
Star Party Location: Mount Shasta Mine Loop Trailhead Parking Lot.
March 2014