Category Archives: Observing

Here we update what the current status of the observing period is.

New results from HPF: planets vs starspots!

The HPF team recently had another publication accepted describing the amazing complexities involved in separating star spots from planets. Their herculean efforts are described on this blog post and in their publication, both linked below:

https://ui.adsabs.harvard.edu/abs/2020arXiv200509657R/abstract

https://arxiv.org/abs/2005.09657

Eternal spotshine of the spinning red suns

New FeAr lamp

After the our Iron-Argon (FeAR) lamp started showing significantly reduced flux, on April 6th our team replaced the bulb in our Facility Calibration Unit (which rides along on the tracker, supplying continuum and line lamps for all the instruments). The new FeAr lamp is back to full brightness and provides excellent narrow emissions lines for our wavelength solutions on the Low Resolution Spectrograph #2.

 

The old bulb (left) looks quite dark and cloudy compared to the new one (right):

FeAr lamp

HET still operating, partially remotely

In response to COVID-19, the HET operations team has been rapidly developing our remote observing capabilities. At present, the night observations are staffed by one telescope operator on site and a remotely-connected resident astronomer (staying at home). Our afternoon operations shift is also being staffed remotely (one remote TO and one remote RA), requiring about 20-30 minutes of assistance from one member of day staff on site for our routine safety checks. Some day time staff are able to work partially or fully remotely from home, but most are still coming in daily as their duties cannot be done over a remote connection. Extra attention is being paid to hygiene, cleanliness, and staff presence each day. To further minimize risk, we have temporarily suspended our schedule of primary mirror segment swaps, as that process requires two members of the mirror team working in very close proximity with each other. We are benefiting from a lot of “can-do” attitudes here and receiving extensive help from our software team to get remote access and learning a lot in this process! After this is all over, I expect we’ll see long-term benefits from the things we have learned throughout this interesting time.

Exciting new results from HPF

HPF’s first new astronomy result is now published!  The team has validated their first planet, G 9-40b.

The article in the Astronomical Journal is available here: https://iopscience.iop.org/article/10.3847/1538-3881/ab5f15

And here is a freely-available version of the paper on the arXiv pre-print server: https://arxiv.org/abs/1912.00291

Press releases on this from PSU, UT are at:

https://science.psu.edu/news/Mahadevan2-2020

https://mcdonaldobservatory.org/news/releases/20200221

For a more publicly-accessible description, see the HPF team’s blog: https://hpf.psu.edu/2020/02/20/g-9-40b-hpfs-first-planet-validation/

Short term DIMM outage

As of Wednesday Feb 12th, the DIMM (Differential Image Motion Monitor) telescope is temporarily out of commission due to a technical problem. We usually run this telescope (mounted a few hundred feet from the HET on a platform to monitor native site seeing) while observing and provide the DIMM image quality (seeing) measurement to PIs with their observations. However these measurements will be temporarily unavailable while we are fixing the issue.

(Edit Feb 22nd: the DIMM functionality has been restored!)

Internet outages recently, getting back to normal now

Currently (Wednesday January 29th, 2020), things appear to be normal again, but we’ve been experiencing issues with internet/network connectivity over the past few days.   In the early morning hours of Sunday January 26th (around 5am) we lost all network/internet access on site.  Some access was restored that evening around 9:45pm, but connections were spotty, inconsistent, and some functions were not working.  This affected our real-time data transfers from HET to TACC and has prevented some users from editing their observing programs. All of this functionality appear to have been restored at this time, but if you have any issues please get in touch with us to help.

Results of the 19-2 observing period

We now have the results of the 19-2 observing period which covers from April through the end of July.    During this period we were down for bad weather for 37% of the nights and spent 16.5% of the remaining time doing engineering or instrument commissioning.   Looking at just the clear science time we had the instruments collecting photons 64% of the time.   This better than previous periods and is likely due to the improvements made by the TCS and night staff team to trim down setup times.    We only had 4% down time which suggests the HET is returning to a steady state of reliability.   Our program completion rates fell in the normal range and were 96%, 89%, 91% 72% for our Priority 0, 1, 2 and 3 time.    Of particular note is that we completed 91% of our HETDEX allocation for this period.