Category Archives: Instruments

Here we comment on the Different Instruments for the HET

Hazy skies overhead and HPF discovers the first warm Jupiter around an M dwarf

In the past couple weeks we’ve noticed significant (30-60%) reductions in the amount of starlight reaching the telescope, due to the smoke overhead:

It makes the sunsets eerie and washes out the Milky Way at night, too. Hopefully this situation will improve soon! The extinction seems worst at the blue wavelengths (like those that VIRUS uses) and is not bad for redder light (HPF observations are mostly unaffected).



On the brighter side, yet another HPF paper has been accepted and published – this one is the discovery and confirmation of the first transiting ‘warm’ Jupiter around an M dwarf. You can read the HPF team’s blog post about it:

The PSU press release:

And of course the published article itself:


Hot Jupiters are rare around M dwarfs, and transiting warm Jupiters rarer still. The TESS spacecraft only detected a single transit – and it was only with HPF that we could nail down the orbital period and mass. This one definitely highlights the power of the HET and queue! Congrats to the whole team!

A Young Sub-Neptune-sized Planet Sheds Light onto How Planets Form and Evolve

Check out the latest results from the HET! There was a press release about this fascinating discovery:

For those who want the technical information, see the accepted article on the pre-print server:

In short, this is a planet around a M dwarf in the Hyades cluster (so we know age and metallicity very well- both of which are tricky for M dwarfs), and is more massive  than expected- based on mass derived with HPF radial velocities. With multiple observations during transit we also have determined the spin-orbit alignment of this planet with the rotation axis of its star- which points to a well aligned orbit.
Great work to the HPF team, and the HET staff for another (massively) cool exoplanet discovery!

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:

Eternal spotshine of the spinning red suns

70 VIRUS units on sky

This week the VIRUS spectrograph reached another milestone with 70 active units on sky. Below is a reconstructed/magnified image of one observation (the units actually have gaps between them but are shown magnified here). White squares show the locations for 8 remaining units.

Each dithered VIRUS observation now contains 31,000 spectra covering 46 square arcminutes. Next stop: the full 78 units!


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:

And here is a freely-available version of the paper on the arXiv pre-print server:

Press releases on this from PSU, UT are at:

For a more publicly-accessible description, see the HPF team’s blog:

VIRUS at 59

VIRUS recently celebrated the installation of its 59th unit. Below is a representation of the sky area covered by the current IFUs:


(Note: the VIRUS units (grey squares) do not actually touch each other, but are shown doubled in size to fill in the gaps between them, graphically.)

52 VIRUS units and counting

VIRUS units continue to multiply!  Shown below is a representation of 52 units on the sky:

VIRUS array, expanded images

The grey squares with stars on them are looking at the sky (with more than 23,000 fiberoptic cables taking simultaneous spectra!), and the white squares are empty slots for future units.

The VIRUS units (grey squares) do not actually touch each other, but are shown doubled in size to fill in the gaps between them, graphically.