Hubble at 25!

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On April 24th, the Hubble Space Telescope will celebrate 25 years since its launch. This provides an excellent opportunity to very briefly summarize what I regard as Hubble’s greatest scientific achievements. I should emphasize two things: (1) I have used my personal judgment (and biases) in creating this list; other scientists may have different opinions. (2) I do not claim that these are all exclusive Hubble discoveries. By its very nature as an all-purpose telescope, in most cases Hubble helped cement existing suggestions, rather than making singular discoveries. Nevertheless, in all the topics listed below, Hubble’s contribution has been crucial.

What do I personally regard as Hubble’s “Top 6″ scientific achievements? Here is my list:

(1) The discovery that not only is the expansion of our universe not slowing down, it is accelerating! These findings, made through monitoring distant stellar explosions (called Type Ia supernovae: Figure 1), have led (in combination with other measurements) to the realization that a mysterious form of “dark energy” constitutes about 70% of the cosmic energy budget.

Figure 1. Distant supernova explosions.

(2) The mapping of the large-scale, three-dimensional distribution of “dark matter” — matter that neither emits nor absorbs light, but which forms the scaffolding on which the cosmic structure is constructed.

(3) The determination of the history of the cosmic star-formation rate. This achievement came through a series of deep observations of the universe (Figure 2 shows the “Hubble Ultra-Deep Field 2014″).


Figure 2. The Hubble Ultra-Deep Field 2014. Credit: NASA, ESA, H. Teplitz and M. Rafelski (IPAC/Caltech), A. Koekemoer (STScI), R. Windhorst (ASU), Z. Levay (STScI).

(4) The determination of the Hubble constant — the current rate of cosmic expansion. The uncertainty in the value of this important cosmological parameter has been reduced from a factor of two, to about 3%.

(5) The —> Read More

Harvard’s ‘Frankenstein': The 70s Controversy Over Mixing DNA

In the 1970s, two inhuman creatures—one hairy and tall, another with orange eyes—were spotted in New England. The mayor of Cambridge, Massachusetts, blamed these monsters not on unreliable testimonies, but recombinant DNA technology, then a new and promising laboratory technique.

This outrageous claim was leveled by one Alfred Vellucci, a Cambridge mayor who reserved a unique animosity for academia, and Harvard, especially. He was fond of threatening, for example, to pave the university’s grassy quad over for a parking lot—obviously the best solution to Cambridge’s parking woes. —> Read More

How This D.C. Clinic Wants To ‘De-Medicalize’ Abortion

carafem

“Abortion. Yeah, we do that.”

That’s one of the advertising slogans used by Carafem, an abortion clinic opening this week in Washington, D.C. The clinic plans to approach abortion as a straightforward part of women’s health care, hoping to make the procedure a streamlined process that is easy to access.

Carafem will provide the abortion pill to women who are less than 10 weeks pregnant. Patients will be able to book appointments — offered on evenings and weekends, as well as during weekdays — through an online portal or via a 24-hour hotline manned by multilingual staff members. The clinic also promises a short procedure time of around one hour, and a lower-than-average price point of approximately $400 for an abortion.

Image via Carafem.com

Terminating a pregnancy with the abortion pill involves two steps. Patients take the first pill, mifepristone, which stops the embryo from growing and detaches it from the uterine wall. Between 24 and 72 hours later, they take the second pill, misoprostol, which causes the uterus to contract and expel the embryo. Carafem patients will take the mifepristone pill at the clinic after undergoing tests and speaking with a doctor, then be sent home with the misoprostol pill. Staff members will follow up with each patient to ensure that the termination was successful.

Chris Purdy, the president & CEO of Carafem, told The Huffington Post that he came up with the idea for the clinic around 18 months ago, after returning from 20 years working for family planning programs in Turkey, Ethiopia and Indonesia. Purdy was shocked to find that it was still so difficult for many women in the U.S. to access abortion care. He worked with Melissa S. Grant, a former Planned Parenthood director who is —> Read More

Stunning Photo of Volcanic Lightning at Volcán de Colima in Mexico

The Colima Volcano (Volcán de Colima) pictured on March 29, 2015 with lightning arcing through the ash plume. Credit and copyright: César Cantú.

The Colima Volcano (Volcán de Colima) pictured on March 29, 2015 with lightning arcing through the ash plume. Credit and copyright: César Cantú.

The Colima volcano in Mexico is active again, and has been spewing out large plumes of ash nearly 3 kilometers into the air. Astrophotographer César Cantú captured this spectacular picture of lightning slicing through the cloud of ash.

How can lightning strike in an ash cloud? Through friction, particles of the ash can charge each other by rubbing against each other during the eruption. When the energy is discharged, it can create lightning bolts.
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Read the rest of Stunning Photo of Volcanic Lightning at Volcán de Colima in Mexico (99 words)


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Methods for Maneuvering Through Spring Mud, Vol. 1

Elaine expertly moves through the mud on Sun Prairie North.
My fellow Landmark crew member, Elaine, expertly moves through the mud on Sun Prairie North. (Photo by Tim Brtis)

By Tim Brtis

There is more to walking through mud than just moving each leg in turn.

During my time working with Adventures and Scientists for Conservation’s Landmark project to survey wildlife on the American Prairie Reserve, I’ve learned that proper technique can be the difference between voyaging through the mud at a swift 1.2 mph and struggling in one spot for 15 minutes. Becoming stuck can drain valuable energy, and if freedom isn’t regained you might run the risk of attracting a hungry, circling turkey vulture.

I hereby propose the compilation of an academically thorough guide to mud maneuvering.

I will begin the effort by sharing the knowledge a coworker and I have compiled here. However, because I don’t possess every stratagem related to mud walking, I plan to consult experts from around the world for future volumes.

Lesson 1: Techniques for Efficient Movement
It’s best to avoid becoming stuck. Maintaining your liberty may require one or more of the following techniques.

The Pointed-Foot Technique
While trudging through an increasingly mucky area, I could feel the ground playfully tugging at my feet with each step. Eventually, the mud got greedy and did not let go. With my next step denied, I was pulled back to the gluttonous ground, which then took my second foot.

“Walk on the balls of your feet, and you don’t stick as much!” Elaine called over to me. I tried walking in place using this technique and was promptly liberated.

Walking on the balls of your feet keeps your heels from planting in the mud, thereby preventing suction from forming between the mud and the bottom of your boots. Science.

The Don’t-Slow-Down Method
While venturing further into that same mud field, I found that if I stopped —> Read More

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